2106 lines
51 KiB
C
2106 lines
51 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* inode.c -- user mode filesystem api for usb gadget controllers
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*
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* Copyright (C) 2003-2004 David Brownell
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* Copyright (C) 2003 Agilent Technologies
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*/
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/* #define VERBOSE_DEBUG */
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/fs.h>
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#include <linux/fs_context.h>
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#include <linux/pagemap.h>
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#include <linux/uts.h>
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#include <linux/wait.h>
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#include <linux/compiler.h>
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#include <linux/uaccess.h>
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#include <linux/sched.h>
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#include <linux/slab.h>
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#include <linux/poll.h>
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#include <linux/mmu_context.h>
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#include <linux/aio.h>
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#include <linux/uio.h>
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#include <linux/refcount.h>
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#include <linux/delay.h>
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#include <linux/device.h>
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#include <linux/moduleparam.h>
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#include <linux/usb/gadgetfs.h>
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#include <linux/usb/gadget.h>
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/*
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* The gadgetfs API maps each endpoint to a file descriptor so that you
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* can use standard synchronous read/write calls for I/O. There's some
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* O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode
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* drivers show how this works in practice. You can also use AIO to
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* eliminate I/O gaps between requests, to help when streaming data.
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*
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* Key parts that must be USB-specific are protocols defining how the
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* read/write operations relate to the hardware state machines. There
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* are two types of files. One type is for the device, implementing ep0.
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* The other type is for each IN or OUT endpoint. In both cases, the
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* user mode driver must configure the hardware before using it.
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*
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* - First, dev_config() is called when /dev/gadget/$CHIP is configured
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* (by writing configuration and device descriptors). Afterwards it
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* may serve as a source of device events, used to handle all control
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* requests other than basic enumeration.
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*
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* - Then, after a SET_CONFIGURATION control request, ep_config() is
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* called when each /dev/gadget/ep* file is configured (by writing
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* endpoint descriptors). Afterwards these files are used to write()
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* IN data or to read() OUT data. To halt the endpoint, a "wrong
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* direction" request is issued (like reading an IN endpoint).
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*
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* Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
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* not possible on all hardware. For example, precise fault handling with
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* respect to data left in endpoint fifos after aborted operations; or
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* selective clearing of endpoint halts, to implement SET_INTERFACE.
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*/
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#define DRIVER_DESC "USB Gadget filesystem"
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#define DRIVER_VERSION "24 Aug 2004"
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static const char driver_desc [] = DRIVER_DESC;
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static const char shortname [] = "gadgetfs";
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MODULE_DESCRIPTION (DRIVER_DESC);
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MODULE_AUTHOR ("David Brownell");
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MODULE_LICENSE ("GPL");
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static int ep_open(struct inode *, struct file *);
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/*----------------------------------------------------------------------*/
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#define GADGETFS_MAGIC 0xaee71ee7
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/* /dev/gadget/$CHIP represents ep0 and the whole device */
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enum ep0_state {
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/* DISABLED is the initial state. */
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STATE_DEV_DISABLED = 0,
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/* Only one open() of /dev/gadget/$CHIP; only one file tracks
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* ep0/device i/o modes and binding to the controller. Driver
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* must always write descriptors to initialize the device, then
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* the device becomes UNCONNECTED until enumeration.
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*/
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STATE_DEV_OPENED,
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/* From then on, ep0 fd is in either of two basic modes:
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* - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
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* - SETUP: read/write will transfer control data and succeed;
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* or if "wrong direction", performs protocol stall
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*/
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STATE_DEV_UNCONNECTED,
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STATE_DEV_CONNECTED,
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STATE_DEV_SETUP,
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/* UNBOUND means the driver closed ep0, so the device won't be
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* accessible again (DEV_DISABLED) until all fds are closed.
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*/
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STATE_DEV_UNBOUND,
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};
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/* enough for the whole queue: most events invalidate others */
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#define N_EVENT 5
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struct dev_data {
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spinlock_t lock;
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refcount_t count;
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int udc_usage;
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enum ep0_state state; /* P: lock */
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struct usb_gadgetfs_event event [N_EVENT];
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unsigned ev_next;
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struct fasync_struct *fasync;
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u8 current_config;
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/* drivers reading ep0 MUST handle control requests (SETUP)
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* reported that way; else the host will time out.
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*/
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unsigned usermode_setup : 1,
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setup_in : 1,
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setup_can_stall : 1,
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setup_out_ready : 1,
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setup_out_error : 1,
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setup_abort : 1,
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gadget_registered : 1;
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unsigned setup_wLength;
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/* the rest is basically write-once */
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struct usb_config_descriptor *config, *hs_config;
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struct usb_device_descriptor *dev;
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struct usb_request *req;
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struct usb_gadget *gadget;
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struct list_head epfiles;
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void *buf;
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wait_queue_head_t wait;
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struct super_block *sb;
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struct dentry *dentry;
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/* except this scratch i/o buffer for ep0 */
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u8 rbuf [256];
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};
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static inline void get_dev (struct dev_data *data)
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{
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refcount_inc (&data->count);
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}
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static void put_dev (struct dev_data *data)
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{
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if (likely (!refcount_dec_and_test (&data->count)))
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return;
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/* needs no more cleanup */
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BUG_ON (waitqueue_active (&data->wait));
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kfree (data);
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}
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static struct dev_data *dev_new (void)
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{
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struct dev_data *dev;
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dev = kzalloc(sizeof(*dev), GFP_KERNEL);
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if (!dev)
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return NULL;
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dev->state = STATE_DEV_DISABLED;
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refcount_set (&dev->count, 1);
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spin_lock_init (&dev->lock);
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INIT_LIST_HEAD (&dev->epfiles);
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init_waitqueue_head (&dev->wait);
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return dev;
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}
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/*----------------------------------------------------------------------*/
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/* other /dev/gadget/$ENDPOINT files represent endpoints */
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enum ep_state {
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STATE_EP_DISABLED = 0,
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STATE_EP_READY,
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STATE_EP_ENABLED,
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STATE_EP_UNBOUND,
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};
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struct ep_data {
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struct mutex lock;
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enum ep_state state;
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refcount_t count;
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struct dev_data *dev;
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/* must hold dev->lock before accessing ep or req */
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struct usb_ep *ep;
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struct usb_request *req;
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ssize_t status;
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char name [16];
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struct usb_endpoint_descriptor desc, hs_desc;
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struct list_head epfiles;
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wait_queue_head_t wait;
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struct dentry *dentry;
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};
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static inline void get_ep (struct ep_data *data)
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{
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refcount_inc (&data->count);
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}
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static void put_ep (struct ep_data *data)
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{
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if (likely (!refcount_dec_and_test (&data->count)))
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return;
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put_dev (data->dev);
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/* needs no more cleanup */
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BUG_ON (!list_empty (&data->epfiles));
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BUG_ON (waitqueue_active (&data->wait));
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kfree (data);
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}
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/*----------------------------------------------------------------------*/
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/* most "how to use the hardware" policy choices are in userspace:
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* mapping endpoint roles (which the driver needs) to the capabilities
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* which the usb controller has. most of those capabilities are exposed
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* implicitly, starting with the driver name and then endpoint names.
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*/
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static const char *CHIP;
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/*----------------------------------------------------------------------*/
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/* NOTE: don't use dev_printk calls before binding to the gadget
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* at the end of ep0 configuration, or after unbind.
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*/
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/* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
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#define xprintk(d,level,fmt,args...) \
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printk(level "%s: " fmt , shortname , ## args)
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#ifdef DEBUG
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#define DBG(dev,fmt,args...) \
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xprintk(dev , KERN_DEBUG , fmt , ## args)
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#else
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#define DBG(dev,fmt,args...) \
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do { } while (0)
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#endif /* DEBUG */
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#ifdef VERBOSE_DEBUG
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#define VDEBUG DBG
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#else
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#define VDEBUG(dev,fmt,args...) \
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do { } while (0)
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#endif /* DEBUG */
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#define ERROR(dev,fmt,args...) \
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xprintk(dev , KERN_ERR , fmt , ## args)
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#define INFO(dev,fmt,args...) \
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xprintk(dev , KERN_INFO , fmt , ## args)
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/*----------------------------------------------------------------------*/
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/* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
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*
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* After opening, configure non-control endpoints. Then use normal
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* stream read() and write() requests; and maybe ioctl() to get more
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* precise FIFO status when recovering from cancellation.
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*/
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static void epio_complete (struct usb_ep *ep, struct usb_request *req)
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{
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struct ep_data *epdata = ep->driver_data;
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if (!req->context)
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return;
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if (req->status)
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epdata->status = req->status;
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else
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epdata->status = req->actual;
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complete ((struct completion *)req->context);
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}
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/* tasklock endpoint, returning when it's connected.
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* still need dev->lock to use epdata->ep.
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*/
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static int
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get_ready_ep (unsigned f_flags, struct ep_data *epdata, bool is_write)
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{
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int val;
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if (f_flags & O_NONBLOCK) {
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if (!mutex_trylock(&epdata->lock))
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goto nonblock;
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if (epdata->state != STATE_EP_ENABLED &&
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(!is_write || epdata->state != STATE_EP_READY)) {
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mutex_unlock(&epdata->lock);
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nonblock:
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val = -EAGAIN;
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} else
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val = 0;
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return val;
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}
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val = mutex_lock_interruptible(&epdata->lock);
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if (val < 0)
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return val;
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switch (epdata->state) {
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case STATE_EP_ENABLED:
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return 0;
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case STATE_EP_READY: /* not configured yet */
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if (is_write)
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return 0;
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// FALLTHRU
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case STATE_EP_UNBOUND: /* clean disconnect */
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break;
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// case STATE_EP_DISABLED: /* "can't happen" */
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default: /* error! */
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pr_debug ("%s: ep %p not available, state %d\n",
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shortname, epdata, epdata->state);
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}
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mutex_unlock(&epdata->lock);
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return -ENODEV;
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}
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static ssize_t
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ep_io (struct ep_data *epdata, void *buf, unsigned len)
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{
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DECLARE_COMPLETION_ONSTACK (done);
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int value;
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spin_lock_irq (&epdata->dev->lock);
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if (likely (epdata->ep != NULL)) {
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struct usb_request *req = epdata->req;
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req->context = &done;
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req->complete = epio_complete;
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req->buf = buf;
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req->length = len;
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value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
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} else
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value = -ENODEV;
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spin_unlock_irq (&epdata->dev->lock);
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if (likely (value == 0)) {
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value = wait_event_interruptible (done.wait, done.done);
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if (value != 0) {
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spin_lock_irq (&epdata->dev->lock);
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if (likely (epdata->ep != NULL)) {
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DBG (epdata->dev, "%s i/o interrupted\n",
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epdata->name);
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usb_ep_dequeue (epdata->ep, epdata->req);
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spin_unlock_irq (&epdata->dev->lock);
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wait_event (done.wait, done.done);
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if (epdata->status == -ECONNRESET)
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epdata->status = -EINTR;
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} else {
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spin_unlock_irq (&epdata->dev->lock);
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DBG (epdata->dev, "endpoint gone\n");
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epdata->status = -ENODEV;
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}
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}
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return epdata->status;
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}
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return value;
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}
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static int
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ep_release (struct inode *inode, struct file *fd)
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{
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struct ep_data *data = fd->private_data;
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int value;
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value = mutex_lock_interruptible(&data->lock);
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if (value < 0)
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return value;
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/* clean up if this can be reopened */
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if (data->state != STATE_EP_UNBOUND) {
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data->state = STATE_EP_DISABLED;
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data->desc.bDescriptorType = 0;
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data->hs_desc.bDescriptorType = 0;
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usb_ep_disable(data->ep);
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}
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mutex_unlock(&data->lock);
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put_ep (data);
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return 0;
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}
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static long ep_ioctl(struct file *fd, unsigned code, unsigned long value)
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{
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struct ep_data *data = fd->private_data;
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int status;
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if ((status = get_ready_ep (fd->f_flags, data, false)) < 0)
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return status;
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spin_lock_irq (&data->dev->lock);
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if (likely (data->ep != NULL)) {
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switch (code) {
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case GADGETFS_FIFO_STATUS:
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status = usb_ep_fifo_status (data->ep);
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break;
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case GADGETFS_FIFO_FLUSH:
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usb_ep_fifo_flush (data->ep);
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break;
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case GADGETFS_CLEAR_HALT:
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status = usb_ep_clear_halt (data->ep);
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break;
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default:
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status = -ENOTTY;
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}
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} else
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status = -ENODEV;
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spin_unlock_irq (&data->dev->lock);
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mutex_unlock(&data->lock);
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return status;
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}
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/*----------------------------------------------------------------------*/
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/* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
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struct kiocb_priv {
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struct usb_request *req;
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struct ep_data *epdata;
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struct kiocb *iocb;
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struct mm_struct *mm;
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struct work_struct work;
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void *buf;
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struct iov_iter to;
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const void *to_free;
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unsigned actual;
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};
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static int ep_aio_cancel(struct kiocb *iocb)
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{
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struct kiocb_priv *priv = iocb->private;
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struct ep_data *epdata;
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int value;
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local_irq_disable();
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epdata = priv->epdata;
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// spin_lock(&epdata->dev->lock);
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if (likely(epdata && epdata->ep && priv->req))
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value = usb_ep_dequeue (epdata->ep, priv->req);
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else
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value = -EINVAL;
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// spin_unlock(&epdata->dev->lock);
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local_irq_enable();
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return value;
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}
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static void ep_user_copy_worker(struct work_struct *work)
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{
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struct kiocb_priv *priv = container_of(work, struct kiocb_priv, work);
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struct mm_struct *mm = priv->mm;
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struct kiocb *iocb = priv->iocb;
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size_t ret;
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use_mm(mm);
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ret = copy_to_iter(priv->buf, priv->actual, &priv->to);
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unuse_mm(mm);
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if (!ret)
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ret = -EFAULT;
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/* completing the iocb can drop the ctx and mm, don't touch mm after */
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iocb->ki_complete(iocb, ret, ret);
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kfree(priv->buf);
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kfree(priv->to_free);
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kfree(priv);
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}
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static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
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{
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struct kiocb *iocb = req->context;
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struct kiocb_priv *priv = iocb->private;
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struct ep_data *epdata = priv->epdata;
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/* lock against disconnect (and ideally, cancel) */
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spin_lock(&epdata->dev->lock);
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priv->req = NULL;
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priv->epdata = NULL;
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/* if this was a write or a read returning no data then we
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* don't need to copy anything to userspace, so we can
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* complete the aio request immediately.
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*/
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if (priv->to_free == NULL || unlikely(req->actual == 0)) {
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kfree(req->buf);
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kfree(priv->to_free);
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kfree(priv);
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iocb->private = NULL;
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/* aio_complete() reports bytes-transferred _and_ faults */
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iocb->ki_complete(iocb, req->actual ? req->actual : req->status,
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req->status);
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} else {
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/* ep_copy_to_user() won't report both; we hide some faults */
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if (unlikely(0 != req->status))
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DBG(epdata->dev, "%s fault %d len %d\n",
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ep->name, req->status, req->actual);
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priv->buf = req->buf;
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priv->actual = req->actual;
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INIT_WORK(&priv->work, ep_user_copy_worker);
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schedule_work(&priv->work);
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}
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usb_ep_free_request(ep, req);
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spin_unlock(&epdata->dev->lock);
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put_ep(epdata);
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}
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static ssize_t ep_aio(struct kiocb *iocb,
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struct kiocb_priv *priv,
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struct ep_data *epdata,
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char *buf,
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size_t len)
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{
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struct usb_request *req;
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ssize_t value;
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iocb->private = priv;
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priv->iocb = iocb;
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kiocb_set_cancel_fn(iocb, ep_aio_cancel);
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get_ep(epdata);
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priv->epdata = epdata;
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priv->actual = 0;
|
|
priv->mm = current->mm; /* mm teardown waits for iocbs in exit_aio() */
|
|
|
|
/* each kiocb is coupled to one usb_request, but we can't
|
|
* allocate or submit those if the host disconnected.
|
|
*/
|
|
spin_lock_irq(&epdata->dev->lock);
|
|
value = -ENODEV;
|
|
if (unlikely(epdata->ep == NULL))
|
|
goto fail;
|
|
|
|
req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
|
|
value = -ENOMEM;
|
|
if (unlikely(!req))
|
|
goto fail;
|
|
|
|
priv->req = req;
|
|
req->buf = buf;
|
|
req->length = len;
|
|
req->complete = ep_aio_complete;
|
|
req->context = iocb;
|
|
value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
|
|
if (unlikely(0 != value)) {
|
|
usb_ep_free_request(epdata->ep, req);
|
|
goto fail;
|
|
}
|
|
spin_unlock_irq(&epdata->dev->lock);
|
|
return -EIOCBQUEUED;
|
|
|
|
fail:
|
|
spin_unlock_irq(&epdata->dev->lock);
|
|
kfree(priv->to_free);
|
|
kfree(priv);
|
|
put_ep(epdata);
|
|
return value;
|
|
}
|
|
|
|
static ssize_t
|
|
ep_read_iter(struct kiocb *iocb, struct iov_iter *to)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct ep_data *epdata = file->private_data;
|
|
size_t len = iov_iter_count(to);
|
|
ssize_t value;
|
|
char *buf;
|
|
|
|
if ((value = get_ready_ep(file->f_flags, epdata, false)) < 0)
|
|
return value;
|
|
|
|
/* halt any endpoint by doing a "wrong direction" i/o call */
|
|
if (usb_endpoint_dir_in(&epdata->desc)) {
|
|
if (usb_endpoint_xfer_isoc(&epdata->desc) ||
|
|
!is_sync_kiocb(iocb)) {
|
|
mutex_unlock(&epdata->lock);
|
|
return -EINVAL;
|
|
}
|
|
DBG (epdata->dev, "%s halt\n", epdata->name);
|
|
spin_lock_irq(&epdata->dev->lock);
|
|
if (likely(epdata->ep != NULL))
|
|
usb_ep_set_halt(epdata->ep);
|
|
spin_unlock_irq(&epdata->dev->lock);
|
|
mutex_unlock(&epdata->lock);
|
|
return -EBADMSG;
|
|
}
|
|
|
|
buf = kmalloc(len, GFP_KERNEL);
|
|
if (unlikely(!buf)) {
|
|
mutex_unlock(&epdata->lock);
|
|
return -ENOMEM;
|
|
}
|
|
if (is_sync_kiocb(iocb)) {
|
|
value = ep_io(epdata, buf, len);
|
|
if (value >= 0 && (copy_to_iter(buf, value, to) != value))
|
|
value = -EFAULT;
|
|
} else {
|
|
struct kiocb_priv *priv = kzalloc(sizeof *priv, GFP_KERNEL);
|
|
value = -ENOMEM;
|
|
if (!priv)
|
|
goto fail;
|
|
priv->to_free = dup_iter(&priv->to, to, GFP_KERNEL);
|
|
if (!priv->to_free) {
|
|
kfree(priv);
|
|
goto fail;
|
|
}
|
|
value = ep_aio(iocb, priv, epdata, buf, len);
|
|
if (value == -EIOCBQUEUED)
|
|
buf = NULL;
|
|
}
|
|
fail:
|
|
kfree(buf);
|
|
mutex_unlock(&epdata->lock);
|
|
return value;
|
|
}
|
|
|
|
static ssize_t ep_config(struct ep_data *, const char *, size_t);
|
|
|
|
static ssize_t
|
|
ep_write_iter(struct kiocb *iocb, struct iov_iter *from)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct ep_data *epdata = file->private_data;
|
|
size_t len = iov_iter_count(from);
|
|
bool configured;
|
|
ssize_t value;
|
|
char *buf;
|
|
|
|
if ((value = get_ready_ep(file->f_flags, epdata, true)) < 0)
|
|
return value;
|
|
|
|
configured = epdata->state == STATE_EP_ENABLED;
|
|
|
|
/* halt any endpoint by doing a "wrong direction" i/o call */
|
|
if (configured && !usb_endpoint_dir_in(&epdata->desc)) {
|
|
if (usb_endpoint_xfer_isoc(&epdata->desc) ||
|
|
!is_sync_kiocb(iocb)) {
|
|
mutex_unlock(&epdata->lock);
|
|
return -EINVAL;
|
|
}
|
|
DBG (epdata->dev, "%s halt\n", epdata->name);
|
|
spin_lock_irq(&epdata->dev->lock);
|
|
if (likely(epdata->ep != NULL))
|
|
usb_ep_set_halt(epdata->ep);
|
|
spin_unlock_irq(&epdata->dev->lock);
|
|
mutex_unlock(&epdata->lock);
|
|
return -EBADMSG;
|
|
}
|
|
|
|
buf = kmalloc(len, GFP_KERNEL);
|
|
if (unlikely(!buf)) {
|
|
mutex_unlock(&epdata->lock);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
if (unlikely(!copy_from_iter_full(buf, len, from))) {
|
|
value = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
if (unlikely(!configured)) {
|
|
value = ep_config(epdata, buf, len);
|
|
} else if (is_sync_kiocb(iocb)) {
|
|
value = ep_io(epdata, buf, len);
|
|
} else {
|
|
struct kiocb_priv *priv = kzalloc(sizeof *priv, GFP_KERNEL);
|
|
value = -ENOMEM;
|
|
if (priv) {
|
|
value = ep_aio(iocb, priv, epdata, buf, len);
|
|
if (value == -EIOCBQUEUED)
|
|
buf = NULL;
|
|
}
|
|
}
|
|
out:
|
|
kfree(buf);
|
|
mutex_unlock(&epdata->lock);
|
|
return value;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
/* used after endpoint configuration */
|
|
static const struct file_operations ep_io_operations = {
|
|
.owner = THIS_MODULE,
|
|
|
|
.open = ep_open,
|
|
.release = ep_release,
|
|
.llseek = no_llseek,
|
|
.unlocked_ioctl = ep_ioctl,
|
|
.read_iter = ep_read_iter,
|
|
.write_iter = ep_write_iter,
|
|
};
|
|
|
|
/* ENDPOINT INITIALIZATION
|
|
*
|
|
* fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
|
|
* status = write (fd, descriptors, sizeof descriptors)
|
|
*
|
|
* That write establishes the endpoint configuration, configuring
|
|
* the controller to process bulk, interrupt, or isochronous transfers
|
|
* at the right maxpacket size, and so on.
|
|
*
|
|
* The descriptors are message type 1, identified by a host order u32
|
|
* at the beginning of what's written. Descriptor order is: full/low
|
|
* speed descriptor, then optional high speed descriptor.
|
|
*/
|
|
static ssize_t
|
|
ep_config (struct ep_data *data, const char *buf, size_t len)
|
|
{
|
|
struct usb_ep *ep;
|
|
u32 tag;
|
|
int value, length = len;
|
|
|
|
if (data->state != STATE_EP_READY) {
|
|
value = -EL2HLT;
|
|
goto fail;
|
|
}
|
|
|
|
value = len;
|
|
if (len < USB_DT_ENDPOINT_SIZE + 4)
|
|
goto fail0;
|
|
|
|
/* we might need to change message format someday */
|
|
memcpy(&tag, buf, 4);
|
|
if (tag != 1) {
|
|
DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
|
|
goto fail0;
|
|
}
|
|
buf += 4;
|
|
len -= 4;
|
|
|
|
/* NOTE: audio endpoint extensions not accepted here;
|
|
* just don't include the extra bytes.
|
|
*/
|
|
|
|
/* full/low speed descriptor, then high speed */
|
|
memcpy(&data->desc, buf, USB_DT_ENDPOINT_SIZE);
|
|
if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
|
|
|| data->desc.bDescriptorType != USB_DT_ENDPOINT)
|
|
goto fail0;
|
|
if (len != USB_DT_ENDPOINT_SIZE) {
|
|
if (len != 2 * USB_DT_ENDPOINT_SIZE)
|
|
goto fail0;
|
|
memcpy(&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
|
|
USB_DT_ENDPOINT_SIZE);
|
|
if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
|
|
|| data->hs_desc.bDescriptorType
|
|
!= USB_DT_ENDPOINT) {
|
|
DBG(data->dev, "config %s, bad hs length or type\n",
|
|
data->name);
|
|
goto fail0;
|
|
}
|
|
}
|
|
|
|
spin_lock_irq (&data->dev->lock);
|
|
if (data->dev->state == STATE_DEV_UNBOUND) {
|
|
value = -ENOENT;
|
|
goto gone;
|
|
} else {
|
|
ep = data->ep;
|
|
if (ep == NULL) {
|
|
value = -ENODEV;
|
|
goto gone;
|
|
}
|
|
}
|
|
switch (data->dev->gadget->speed) {
|
|
case USB_SPEED_LOW:
|
|
case USB_SPEED_FULL:
|
|
ep->desc = &data->desc;
|
|
break;
|
|
case USB_SPEED_HIGH:
|
|
/* fails if caller didn't provide that descriptor... */
|
|
ep->desc = &data->hs_desc;
|
|
break;
|
|
default:
|
|
DBG(data->dev, "unconnected, %s init abandoned\n",
|
|
data->name);
|
|
value = -EINVAL;
|
|
goto gone;
|
|
}
|
|
value = usb_ep_enable(ep);
|
|
if (value == 0) {
|
|
data->state = STATE_EP_ENABLED;
|
|
value = length;
|
|
}
|
|
gone:
|
|
spin_unlock_irq (&data->dev->lock);
|
|
if (value < 0) {
|
|
fail:
|
|
data->desc.bDescriptorType = 0;
|
|
data->hs_desc.bDescriptorType = 0;
|
|
}
|
|
return value;
|
|
fail0:
|
|
value = -EINVAL;
|
|
goto fail;
|
|
}
|
|
|
|
static int
|
|
ep_open (struct inode *inode, struct file *fd)
|
|
{
|
|
struct ep_data *data = inode->i_private;
|
|
int value = -EBUSY;
|
|
|
|
if (mutex_lock_interruptible(&data->lock) != 0)
|
|
return -EINTR;
|
|
spin_lock_irq (&data->dev->lock);
|
|
if (data->dev->state == STATE_DEV_UNBOUND)
|
|
value = -ENOENT;
|
|
else if (data->state == STATE_EP_DISABLED) {
|
|
value = 0;
|
|
data->state = STATE_EP_READY;
|
|
get_ep (data);
|
|
fd->private_data = data;
|
|
VDEBUG (data->dev, "%s ready\n", data->name);
|
|
} else
|
|
DBG (data->dev, "%s state %d\n",
|
|
data->name, data->state);
|
|
spin_unlock_irq (&data->dev->lock);
|
|
mutex_unlock(&data->lock);
|
|
return value;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
/* EP0 IMPLEMENTATION can be partly in userspace.
|
|
*
|
|
* Drivers that use this facility receive various events, including
|
|
* control requests the kernel doesn't handle. Drivers that don't
|
|
* use this facility may be too simple-minded for real applications.
|
|
*/
|
|
|
|
static inline void ep0_readable (struct dev_data *dev)
|
|
{
|
|
wake_up (&dev->wait);
|
|
kill_fasync (&dev->fasync, SIGIO, POLL_IN);
|
|
}
|
|
|
|
static void clean_req (struct usb_ep *ep, struct usb_request *req)
|
|
{
|
|
struct dev_data *dev = ep->driver_data;
|
|
|
|
if (req->buf != dev->rbuf) {
|
|
kfree(req->buf);
|
|
req->buf = dev->rbuf;
|
|
}
|
|
req->complete = epio_complete;
|
|
dev->setup_out_ready = 0;
|
|
}
|
|
|
|
static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
|
|
{
|
|
struct dev_data *dev = ep->driver_data;
|
|
unsigned long flags;
|
|
int free = 1;
|
|
|
|
/* for control OUT, data must still get to userspace */
|
|
spin_lock_irqsave(&dev->lock, flags);
|
|
if (!dev->setup_in) {
|
|
dev->setup_out_error = (req->status != 0);
|
|
if (!dev->setup_out_error)
|
|
free = 0;
|
|
dev->setup_out_ready = 1;
|
|
ep0_readable (dev);
|
|
}
|
|
|
|
/* clean up as appropriate */
|
|
if (free && req->buf != &dev->rbuf)
|
|
clean_req (ep, req);
|
|
req->complete = epio_complete;
|
|
spin_unlock_irqrestore(&dev->lock, flags);
|
|
}
|
|
|
|
static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
|
|
{
|
|
struct dev_data *dev = ep->driver_data;
|
|
|
|
if (dev->setup_out_ready) {
|
|
DBG (dev, "ep0 request busy!\n");
|
|
return -EBUSY;
|
|
}
|
|
if (len > sizeof (dev->rbuf))
|
|
req->buf = kmalloc(len, GFP_ATOMIC);
|
|
if (req->buf == NULL) {
|
|
req->buf = dev->rbuf;
|
|
return -ENOMEM;
|
|
}
|
|
req->complete = ep0_complete;
|
|
req->length = len;
|
|
req->zero = 0;
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t
|
|
ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
|
|
{
|
|
struct dev_data *dev = fd->private_data;
|
|
ssize_t retval;
|
|
enum ep0_state state;
|
|
|
|
spin_lock_irq (&dev->lock);
|
|
if (dev->state <= STATE_DEV_OPENED) {
|
|
retval = -EINVAL;
|
|
goto done;
|
|
}
|
|
|
|
/* report fd mode change before acting on it */
|
|
if (dev->setup_abort) {
|
|
dev->setup_abort = 0;
|
|
retval = -EIDRM;
|
|
goto done;
|
|
}
|
|
|
|
/* control DATA stage */
|
|
if ((state = dev->state) == STATE_DEV_SETUP) {
|
|
|
|
if (dev->setup_in) { /* stall IN */
|
|
VDEBUG(dev, "ep0in stall\n");
|
|
(void) usb_ep_set_halt (dev->gadget->ep0);
|
|
retval = -EL2HLT;
|
|
dev->state = STATE_DEV_CONNECTED;
|
|
|
|
} else if (len == 0) { /* ack SET_CONFIGURATION etc */
|
|
struct usb_ep *ep = dev->gadget->ep0;
|
|
struct usb_request *req = dev->req;
|
|
|
|
if ((retval = setup_req (ep, req, 0)) == 0) {
|
|
++dev->udc_usage;
|
|
spin_unlock_irq (&dev->lock);
|
|
retval = usb_ep_queue (ep, req, GFP_KERNEL);
|
|
spin_lock_irq (&dev->lock);
|
|
--dev->udc_usage;
|
|
}
|
|
dev->state = STATE_DEV_CONNECTED;
|
|
|
|
/* assume that was SET_CONFIGURATION */
|
|
if (dev->current_config) {
|
|
unsigned power;
|
|
|
|
if (gadget_is_dualspeed(dev->gadget)
|
|
&& (dev->gadget->speed
|
|
== USB_SPEED_HIGH))
|
|
power = dev->hs_config->bMaxPower;
|
|
else
|
|
power = dev->config->bMaxPower;
|
|
usb_gadget_vbus_draw(dev->gadget, 2 * power);
|
|
}
|
|
|
|
} else { /* collect OUT data */
|
|
if ((fd->f_flags & O_NONBLOCK) != 0
|
|
&& !dev->setup_out_ready) {
|
|
retval = -EAGAIN;
|
|
goto done;
|
|
}
|
|
spin_unlock_irq (&dev->lock);
|
|
retval = wait_event_interruptible (dev->wait,
|
|
dev->setup_out_ready != 0);
|
|
|
|
/* FIXME state could change from under us */
|
|
spin_lock_irq (&dev->lock);
|
|
if (retval)
|
|
goto done;
|
|
|
|
if (dev->state != STATE_DEV_SETUP) {
|
|
retval = -ECANCELED;
|
|
goto done;
|
|
}
|
|
dev->state = STATE_DEV_CONNECTED;
|
|
|
|
if (dev->setup_out_error)
|
|
retval = -EIO;
|
|
else {
|
|
len = min (len, (size_t)dev->req->actual);
|
|
++dev->udc_usage;
|
|
spin_unlock_irq(&dev->lock);
|
|
if (copy_to_user (buf, dev->req->buf, len))
|
|
retval = -EFAULT;
|
|
else
|
|
retval = len;
|
|
spin_lock_irq(&dev->lock);
|
|
--dev->udc_usage;
|
|
clean_req (dev->gadget->ep0, dev->req);
|
|
/* NOTE userspace can't yet choose to stall */
|
|
}
|
|
}
|
|
goto done;
|
|
}
|
|
|
|
/* else normal: return event data */
|
|
if (len < sizeof dev->event [0]) {
|
|
retval = -EINVAL;
|
|
goto done;
|
|
}
|
|
len -= len % sizeof (struct usb_gadgetfs_event);
|
|
dev->usermode_setup = 1;
|
|
|
|
scan:
|
|
/* return queued events right away */
|
|
if (dev->ev_next != 0) {
|
|
unsigned i, n;
|
|
|
|
n = len / sizeof (struct usb_gadgetfs_event);
|
|
if (dev->ev_next < n)
|
|
n = dev->ev_next;
|
|
|
|
/* ep0 i/o has special semantics during STATE_DEV_SETUP */
|
|
for (i = 0; i < n; i++) {
|
|
if (dev->event [i].type == GADGETFS_SETUP) {
|
|
dev->state = STATE_DEV_SETUP;
|
|
n = i + 1;
|
|
break;
|
|
}
|
|
}
|
|
spin_unlock_irq (&dev->lock);
|
|
len = n * sizeof (struct usb_gadgetfs_event);
|
|
if (copy_to_user (buf, &dev->event, len))
|
|
retval = -EFAULT;
|
|
else
|
|
retval = len;
|
|
if (len > 0) {
|
|
/* NOTE this doesn't guard against broken drivers;
|
|
* concurrent ep0 readers may lose events.
|
|
*/
|
|
spin_lock_irq (&dev->lock);
|
|
if (dev->ev_next > n) {
|
|
memmove(&dev->event[0], &dev->event[n],
|
|
sizeof (struct usb_gadgetfs_event)
|
|
* (dev->ev_next - n));
|
|
}
|
|
dev->ev_next -= n;
|
|
spin_unlock_irq (&dev->lock);
|
|
}
|
|
return retval;
|
|
}
|
|
if (fd->f_flags & O_NONBLOCK) {
|
|
retval = -EAGAIN;
|
|
goto done;
|
|
}
|
|
|
|
switch (state) {
|
|
default:
|
|
DBG (dev, "fail %s, state %d\n", __func__, state);
|
|
retval = -ESRCH;
|
|
break;
|
|
case STATE_DEV_UNCONNECTED:
|
|
case STATE_DEV_CONNECTED:
|
|
spin_unlock_irq (&dev->lock);
|
|
DBG (dev, "%s wait\n", __func__);
|
|
|
|
/* wait for events */
|
|
retval = wait_event_interruptible (dev->wait,
|
|
dev->ev_next != 0);
|
|
if (retval < 0)
|
|
return retval;
|
|
spin_lock_irq (&dev->lock);
|
|
goto scan;
|
|
}
|
|
|
|
done:
|
|
spin_unlock_irq (&dev->lock);
|
|
return retval;
|
|
}
|
|
|
|
static struct usb_gadgetfs_event *
|
|
next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
|
|
{
|
|
struct usb_gadgetfs_event *event;
|
|
unsigned i;
|
|
|
|
switch (type) {
|
|
/* these events purge the queue */
|
|
case GADGETFS_DISCONNECT:
|
|
if (dev->state == STATE_DEV_SETUP)
|
|
dev->setup_abort = 1;
|
|
// FALL THROUGH
|
|
case GADGETFS_CONNECT:
|
|
dev->ev_next = 0;
|
|
break;
|
|
case GADGETFS_SETUP: /* previous request timed out */
|
|
case GADGETFS_SUSPEND: /* same effect */
|
|
/* these events can't be repeated */
|
|
for (i = 0; i != dev->ev_next; i++) {
|
|
if (dev->event [i].type != type)
|
|
continue;
|
|
DBG(dev, "discard old event[%d] %d\n", i, type);
|
|
dev->ev_next--;
|
|
if (i == dev->ev_next)
|
|
break;
|
|
/* indices start at zero, for simplicity */
|
|
memmove (&dev->event [i], &dev->event [i + 1],
|
|
sizeof (struct usb_gadgetfs_event)
|
|
* (dev->ev_next - i));
|
|
}
|
|
break;
|
|
default:
|
|
BUG ();
|
|
}
|
|
VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type);
|
|
event = &dev->event [dev->ev_next++];
|
|
BUG_ON (dev->ev_next > N_EVENT);
|
|
memset (event, 0, sizeof *event);
|
|
event->type = type;
|
|
return event;
|
|
}
|
|
|
|
static ssize_t
|
|
ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
|
|
{
|
|
struct dev_data *dev = fd->private_data;
|
|
ssize_t retval = -ESRCH;
|
|
|
|
/* report fd mode change before acting on it */
|
|
if (dev->setup_abort) {
|
|
dev->setup_abort = 0;
|
|
retval = -EIDRM;
|
|
|
|
/* data and/or status stage for control request */
|
|
} else if (dev->state == STATE_DEV_SETUP) {
|
|
|
|
len = min_t(size_t, len, dev->setup_wLength);
|
|
if (dev->setup_in) {
|
|
retval = setup_req (dev->gadget->ep0, dev->req, len);
|
|
if (retval == 0) {
|
|
dev->state = STATE_DEV_CONNECTED;
|
|
++dev->udc_usage;
|
|
spin_unlock_irq (&dev->lock);
|
|
if (copy_from_user (dev->req->buf, buf, len))
|
|
retval = -EFAULT;
|
|
else {
|
|
if (len < dev->setup_wLength)
|
|
dev->req->zero = 1;
|
|
retval = usb_ep_queue (
|
|
dev->gadget->ep0, dev->req,
|
|
GFP_KERNEL);
|
|
}
|
|
spin_lock_irq(&dev->lock);
|
|
--dev->udc_usage;
|
|
if (retval < 0) {
|
|
clean_req (dev->gadget->ep0, dev->req);
|
|
} else
|
|
retval = len;
|
|
|
|
return retval;
|
|
}
|
|
|
|
/* can stall some OUT transfers */
|
|
} else if (dev->setup_can_stall) {
|
|
VDEBUG(dev, "ep0out stall\n");
|
|
(void) usb_ep_set_halt (dev->gadget->ep0);
|
|
retval = -EL2HLT;
|
|
dev->state = STATE_DEV_CONNECTED;
|
|
} else {
|
|
DBG(dev, "bogus ep0out stall!\n");
|
|
}
|
|
} else
|
|
DBG (dev, "fail %s, state %d\n", __func__, dev->state);
|
|
|
|
return retval;
|
|
}
|
|
|
|
static int
|
|
ep0_fasync (int f, struct file *fd, int on)
|
|
{
|
|
struct dev_data *dev = fd->private_data;
|
|
// caller must F_SETOWN before signal delivery happens
|
|
VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off");
|
|
return fasync_helper (f, fd, on, &dev->fasync);
|
|
}
|
|
|
|
static struct usb_gadget_driver gadgetfs_driver;
|
|
|
|
static int
|
|
dev_release (struct inode *inode, struct file *fd)
|
|
{
|
|
struct dev_data *dev = fd->private_data;
|
|
|
|
/* closing ep0 === shutdown all */
|
|
|
|
if (dev->gadget_registered) {
|
|
usb_gadget_unregister_driver (&gadgetfs_driver);
|
|
dev->gadget_registered = false;
|
|
}
|
|
|
|
/* at this point "good" hardware has disconnected the
|
|
* device from USB; the host won't see it any more.
|
|
* alternatively, all host requests will time out.
|
|
*/
|
|
|
|
kfree (dev->buf);
|
|
dev->buf = NULL;
|
|
|
|
/* other endpoints were all decoupled from this device */
|
|
spin_lock_irq(&dev->lock);
|
|
dev->state = STATE_DEV_DISABLED;
|
|
spin_unlock_irq(&dev->lock);
|
|
|
|
put_dev (dev);
|
|
return 0;
|
|
}
|
|
|
|
static __poll_t
|
|
ep0_poll (struct file *fd, poll_table *wait)
|
|
{
|
|
struct dev_data *dev = fd->private_data;
|
|
__poll_t mask = 0;
|
|
|
|
if (dev->state <= STATE_DEV_OPENED)
|
|
return DEFAULT_POLLMASK;
|
|
|
|
poll_wait(fd, &dev->wait, wait);
|
|
|
|
spin_lock_irq(&dev->lock);
|
|
|
|
/* report fd mode change before acting on it */
|
|
if (dev->setup_abort) {
|
|
dev->setup_abort = 0;
|
|
mask = EPOLLHUP;
|
|
goto out;
|
|
}
|
|
|
|
if (dev->state == STATE_DEV_SETUP) {
|
|
if (dev->setup_in || dev->setup_can_stall)
|
|
mask = EPOLLOUT;
|
|
} else {
|
|
if (dev->ev_next != 0)
|
|
mask = EPOLLIN;
|
|
}
|
|
out:
|
|
spin_unlock_irq(&dev->lock);
|
|
return mask;
|
|
}
|
|
|
|
static long dev_ioctl (struct file *fd, unsigned code, unsigned long value)
|
|
{
|
|
struct dev_data *dev = fd->private_data;
|
|
struct usb_gadget *gadget = dev->gadget;
|
|
long ret = -ENOTTY;
|
|
|
|
spin_lock_irq(&dev->lock);
|
|
if (dev->state == STATE_DEV_OPENED ||
|
|
dev->state == STATE_DEV_UNBOUND) {
|
|
/* Not bound to a UDC */
|
|
} else if (gadget->ops->ioctl) {
|
|
++dev->udc_usage;
|
|
spin_unlock_irq(&dev->lock);
|
|
|
|
ret = gadget->ops->ioctl (gadget, code, value);
|
|
|
|
spin_lock_irq(&dev->lock);
|
|
--dev->udc_usage;
|
|
}
|
|
spin_unlock_irq(&dev->lock);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
/* The in-kernel gadget driver handles most ep0 issues, in particular
|
|
* enumerating the single configuration (as provided from user space).
|
|
*
|
|
* Unrecognized ep0 requests may be handled in user space.
|
|
*/
|
|
|
|
static void make_qualifier (struct dev_data *dev)
|
|
{
|
|
struct usb_qualifier_descriptor qual;
|
|
struct usb_device_descriptor *desc;
|
|
|
|
qual.bLength = sizeof qual;
|
|
qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
|
|
qual.bcdUSB = cpu_to_le16 (0x0200);
|
|
|
|
desc = dev->dev;
|
|
qual.bDeviceClass = desc->bDeviceClass;
|
|
qual.bDeviceSubClass = desc->bDeviceSubClass;
|
|
qual.bDeviceProtocol = desc->bDeviceProtocol;
|
|
|
|
/* assumes ep0 uses the same value for both speeds ... */
|
|
qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
|
|
|
|
qual.bNumConfigurations = 1;
|
|
qual.bRESERVED = 0;
|
|
|
|
memcpy (dev->rbuf, &qual, sizeof qual);
|
|
}
|
|
|
|
static int
|
|
config_buf (struct dev_data *dev, u8 type, unsigned index)
|
|
{
|
|
int len;
|
|
int hs = 0;
|
|
|
|
/* only one configuration */
|
|
if (index > 0)
|
|
return -EINVAL;
|
|
|
|
if (gadget_is_dualspeed(dev->gadget)) {
|
|
hs = (dev->gadget->speed == USB_SPEED_HIGH);
|
|
if (type == USB_DT_OTHER_SPEED_CONFIG)
|
|
hs = !hs;
|
|
}
|
|
if (hs) {
|
|
dev->req->buf = dev->hs_config;
|
|
len = le16_to_cpu(dev->hs_config->wTotalLength);
|
|
} else {
|
|
dev->req->buf = dev->config;
|
|
len = le16_to_cpu(dev->config->wTotalLength);
|
|
}
|
|
((u8 *)dev->req->buf) [1] = type;
|
|
return len;
|
|
}
|
|
|
|
static int
|
|
gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
|
|
{
|
|
struct dev_data *dev = get_gadget_data (gadget);
|
|
struct usb_request *req = dev->req;
|
|
int value = -EOPNOTSUPP;
|
|
struct usb_gadgetfs_event *event;
|
|
u16 w_value = le16_to_cpu(ctrl->wValue);
|
|
u16 w_length = le16_to_cpu(ctrl->wLength);
|
|
|
|
spin_lock (&dev->lock);
|
|
dev->setup_abort = 0;
|
|
if (dev->state == STATE_DEV_UNCONNECTED) {
|
|
if (gadget_is_dualspeed(gadget)
|
|
&& gadget->speed == USB_SPEED_HIGH
|
|
&& dev->hs_config == NULL) {
|
|
spin_unlock(&dev->lock);
|
|
ERROR (dev, "no high speed config??\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
dev->state = STATE_DEV_CONNECTED;
|
|
|
|
INFO (dev, "connected\n");
|
|
event = next_event (dev, GADGETFS_CONNECT);
|
|
event->u.speed = gadget->speed;
|
|
ep0_readable (dev);
|
|
|
|
/* host may have given up waiting for response. we can miss control
|
|
* requests handled lower down (device/endpoint status and features);
|
|
* then ep0_{read,write} will report the wrong status. controller
|
|
* driver will have aborted pending i/o.
|
|
*/
|
|
} else if (dev->state == STATE_DEV_SETUP)
|
|
dev->setup_abort = 1;
|
|
|
|
req->buf = dev->rbuf;
|
|
req->context = NULL;
|
|
value = -EOPNOTSUPP;
|
|
switch (ctrl->bRequest) {
|
|
|
|
case USB_REQ_GET_DESCRIPTOR:
|
|
if (ctrl->bRequestType != USB_DIR_IN)
|
|
goto unrecognized;
|
|
switch (w_value >> 8) {
|
|
|
|
case USB_DT_DEVICE:
|
|
value = min (w_length, (u16) sizeof *dev->dev);
|
|
dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket;
|
|
req->buf = dev->dev;
|
|
break;
|
|
case USB_DT_DEVICE_QUALIFIER:
|
|
if (!dev->hs_config)
|
|
break;
|
|
value = min (w_length, (u16)
|
|
sizeof (struct usb_qualifier_descriptor));
|
|
make_qualifier (dev);
|
|
break;
|
|
case USB_DT_OTHER_SPEED_CONFIG:
|
|
// FALLTHROUGH
|
|
case USB_DT_CONFIG:
|
|
value = config_buf (dev,
|
|
w_value >> 8,
|
|
w_value & 0xff);
|
|
if (value >= 0)
|
|
value = min (w_length, (u16) value);
|
|
break;
|
|
case USB_DT_STRING:
|
|
goto unrecognized;
|
|
|
|
default: // all others are errors
|
|
break;
|
|
}
|
|
break;
|
|
|
|
/* currently one config, two speeds */
|
|
case USB_REQ_SET_CONFIGURATION:
|
|
if (ctrl->bRequestType != 0)
|
|
goto unrecognized;
|
|
if (0 == (u8) w_value) {
|
|
value = 0;
|
|
dev->current_config = 0;
|
|
usb_gadget_vbus_draw(gadget, 8 /* mA */ );
|
|
// user mode expected to disable endpoints
|
|
} else {
|
|
u8 config, power;
|
|
|
|
if (gadget_is_dualspeed(gadget)
|
|
&& gadget->speed == USB_SPEED_HIGH) {
|
|
config = dev->hs_config->bConfigurationValue;
|
|
power = dev->hs_config->bMaxPower;
|
|
} else {
|
|
config = dev->config->bConfigurationValue;
|
|
power = dev->config->bMaxPower;
|
|
}
|
|
|
|
if (config == (u8) w_value) {
|
|
value = 0;
|
|
dev->current_config = config;
|
|
usb_gadget_vbus_draw(gadget, 2 * power);
|
|
}
|
|
}
|
|
|
|
/* report SET_CONFIGURATION like any other control request,
|
|
* except that usermode may not stall this. the next
|
|
* request mustn't be allowed start until this finishes:
|
|
* endpoints and threads set up, etc.
|
|
*
|
|
* NOTE: older PXA hardware (before PXA 255: without UDCCFR)
|
|
* has bad/racey automagic that prevents synchronizing here.
|
|
* even kernel mode drivers often miss them.
|
|
*/
|
|
if (value == 0) {
|
|
INFO (dev, "configuration #%d\n", dev->current_config);
|
|
usb_gadget_set_state(gadget, USB_STATE_CONFIGURED);
|
|
if (dev->usermode_setup) {
|
|
dev->setup_can_stall = 0;
|
|
goto delegate;
|
|
}
|
|
}
|
|
break;
|
|
|
|
#ifndef CONFIG_USB_PXA25X
|
|
/* PXA automagically handles this request too */
|
|
case USB_REQ_GET_CONFIGURATION:
|
|
if (ctrl->bRequestType != 0x80)
|
|
goto unrecognized;
|
|
*(u8 *)req->buf = dev->current_config;
|
|
value = min (w_length, (u16) 1);
|
|
break;
|
|
#endif
|
|
|
|
default:
|
|
unrecognized:
|
|
VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
|
|
dev->usermode_setup ? "delegate" : "fail",
|
|
ctrl->bRequestType, ctrl->bRequest,
|
|
w_value, le16_to_cpu(ctrl->wIndex), w_length);
|
|
|
|
/* if there's an ep0 reader, don't stall */
|
|
if (dev->usermode_setup) {
|
|
dev->setup_can_stall = 1;
|
|
delegate:
|
|
dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
|
|
? 1 : 0;
|
|
dev->setup_wLength = w_length;
|
|
dev->setup_out_ready = 0;
|
|
dev->setup_out_error = 0;
|
|
|
|
/* read DATA stage for OUT right away */
|
|
if (unlikely (!dev->setup_in && w_length)) {
|
|
value = setup_req (gadget->ep0, dev->req,
|
|
w_length);
|
|
if (value < 0)
|
|
break;
|
|
|
|
++dev->udc_usage;
|
|
spin_unlock (&dev->lock);
|
|
value = usb_ep_queue (gadget->ep0, dev->req,
|
|
GFP_KERNEL);
|
|
spin_lock (&dev->lock);
|
|
--dev->udc_usage;
|
|
if (value < 0) {
|
|
clean_req (gadget->ep0, dev->req);
|
|
break;
|
|
}
|
|
|
|
/* we can't currently stall these */
|
|
dev->setup_can_stall = 0;
|
|
}
|
|
|
|
/* state changes when reader collects event */
|
|
event = next_event (dev, GADGETFS_SETUP);
|
|
event->u.setup = *ctrl;
|
|
ep0_readable (dev);
|
|
spin_unlock (&dev->lock);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* proceed with data transfer and status phases? */
|
|
if (value >= 0 && dev->state != STATE_DEV_SETUP) {
|
|
req->length = value;
|
|
req->zero = value < w_length;
|
|
|
|
++dev->udc_usage;
|
|
spin_unlock (&dev->lock);
|
|
value = usb_ep_queue (gadget->ep0, req, GFP_KERNEL);
|
|
spin_lock(&dev->lock);
|
|
--dev->udc_usage;
|
|
spin_unlock(&dev->lock);
|
|
if (value < 0) {
|
|
DBG (dev, "ep_queue --> %d\n", value);
|
|
req->status = 0;
|
|
}
|
|
return value;
|
|
}
|
|
|
|
/* device stalls when value < 0 */
|
|
spin_unlock (&dev->lock);
|
|
return value;
|
|
}
|
|
|
|
static void destroy_ep_files (struct dev_data *dev)
|
|
{
|
|
DBG (dev, "%s %d\n", __func__, dev->state);
|
|
|
|
/* dev->state must prevent interference */
|
|
spin_lock_irq (&dev->lock);
|
|
while (!list_empty(&dev->epfiles)) {
|
|
struct ep_data *ep;
|
|
struct inode *parent;
|
|
struct dentry *dentry;
|
|
|
|
/* break link to FS */
|
|
ep = list_first_entry (&dev->epfiles, struct ep_data, epfiles);
|
|
list_del_init (&ep->epfiles);
|
|
spin_unlock_irq (&dev->lock);
|
|
|
|
dentry = ep->dentry;
|
|
ep->dentry = NULL;
|
|
parent = d_inode(dentry->d_parent);
|
|
|
|
/* break link to controller */
|
|
mutex_lock(&ep->lock);
|
|
if (ep->state == STATE_EP_ENABLED)
|
|
(void) usb_ep_disable (ep->ep);
|
|
ep->state = STATE_EP_UNBOUND;
|
|
usb_ep_free_request (ep->ep, ep->req);
|
|
ep->ep = NULL;
|
|
mutex_unlock(&ep->lock);
|
|
|
|
wake_up (&ep->wait);
|
|
put_ep (ep);
|
|
|
|
/* break link to dcache */
|
|
inode_lock(parent);
|
|
d_delete (dentry);
|
|
dput (dentry);
|
|
inode_unlock(parent);
|
|
|
|
spin_lock_irq (&dev->lock);
|
|
}
|
|
spin_unlock_irq (&dev->lock);
|
|
}
|
|
|
|
|
|
static struct dentry *
|
|
gadgetfs_create_file (struct super_block *sb, char const *name,
|
|
void *data, const struct file_operations *fops);
|
|
|
|
static int activate_ep_files (struct dev_data *dev)
|
|
{
|
|
struct usb_ep *ep;
|
|
struct ep_data *data;
|
|
|
|
gadget_for_each_ep (ep, dev->gadget) {
|
|
|
|
data = kzalloc(sizeof(*data), GFP_KERNEL);
|
|
if (!data)
|
|
goto enomem0;
|
|
data->state = STATE_EP_DISABLED;
|
|
mutex_init(&data->lock);
|
|
init_waitqueue_head (&data->wait);
|
|
|
|
strncpy (data->name, ep->name, sizeof (data->name) - 1);
|
|
refcount_set (&data->count, 1);
|
|
data->dev = dev;
|
|
get_dev (dev);
|
|
|
|
data->ep = ep;
|
|
ep->driver_data = data;
|
|
|
|
data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
|
|
if (!data->req)
|
|
goto enomem1;
|
|
|
|
data->dentry = gadgetfs_create_file (dev->sb, data->name,
|
|
data, &ep_io_operations);
|
|
if (!data->dentry)
|
|
goto enomem2;
|
|
list_add_tail (&data->epfiles, &dev->epfiles);
|
|
}
|
|
return 0;
|
|
|
|
enomem2:
|
|
usb_ep_free_request (ep, data->req);
|
|
enomem1:
|
|
put_dev (dev);
|
|
kfree (data);
|
|
enomem0:
|
|
DBG (dev, "%s enomem\n", __func__);
|
|
destroy_ep_files (dev);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void
|
|
gadgetfs_unbind (struct usb_gadget *gadget)
|
|
{
|
|
struct dev_data *dev = get_gadget_data (gadget);
|
|
|
|
DBG (dev, "%s\n", __func__);
|
|
|
|
spin_lock_irq (&dev->lock);
|
|
dev->state = STATE_DEV_UNBOUND;
|
|
while (dev->udc_usage > 0) {
|
|
spin_unlock_irq(&dev->lock);
|
|
usleep_range(1000, 2000);
|
|
spin_lock_irq(&dev->lock);
|
|
}
|
|
spin_unlock_irq (&dev->lock);
|
|
|
|
destroy_ep_files (dev);
|
|
gadget->ep0->driver_data = NULL;
|
|
set_gadget_data (gadget, NULL);
|
|
|
|
/* we've already been disconnected ... no i/o is active */
|
|
if (dev->req)
|
|
usb_ep_free_request (gadget->ep0, dev->req);
|
|
DBG (dev, "%s done\n", __func__);
|
|
put_dev (dev);
|
|
}
|
|
|
|
static struct dev_data *the_device;
|
|
|
|
static int gadgetfs_bind(struct usb_gadget *gadget,
|
|
struct usb_gadget_driver *driver)
|
|
{
|
|
struct dev_data *dev = the_device;
|
|
|
|
if (!dev)
|
|
return -ESRCH;
|
|
if (0 != strcmp (CHIP, gadget->name)) {
|
|
pr_err("%s expected %s controller not %s\n",
|
|
shortname, CHIP, gadget->name);
|
|
return -ENODEV;
|
|
}
|
|
|
|
set_gadget_data (gadget, dev);
|
|
dev->gadget = gadget;
|
|
gadget->ep0->driver_data = dev;
|
|
|
|
/* preallocate control response and buffer */
|
|
dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
|
|
if (!dev->req)
|
|
goto enomem;
|
|
dev->req->context = NULL;
|
|
dev->req->complete = epio_complete;
|
|
|
|
if (activate_ep_files (dev) < 0)
|
|
goto enomem;
|
|
|
|
INFO (dev, "bound to %s driver\n", gadget->name);
|
|
spin_lock_irq(&dev->lock);
|
|
dev->state = STATE_DEV_UNCONNECTED;
|
|
spin_unlock_irq(&dev->lock);
|
|
get_dev (dev);
|
|
return 0;
|
|
|
|
enomem:
|
|
gadgetfs_unbind (gadget);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void
|
|
gadgetfs_disconnect (struct usb_gadget *gadget)
|
|
{
|
|
struct dev_data *dev = get_gadget_data (gadget);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave (&dev->lock, flags);
|
|
if (dev->state == STATE_DEV_UNCONNECTED)
|
|
goto exit;
|
|
dev->state = STATE_DEV_UNCONNECTED;
|
|
|
|
INFO (dev, "disconnected\n");
|
|
next_event (dev, GADGETFS_DISCONNECT);
|
|
ep0_readable (dev);
|
|
exit:
|
|
spin_unlock_irqrestore (&dev->lock, flags);
|
|
}
|
|
|
|
static void
|
|
gadgetfs_suspend (struct usb_gadget *gadget)
|
|
{
|
|
struct dev_data *dev = get_gadget_data (gadget);
|
|
unsigned long flags;
|
|
|
|
INFO (dev, "suspended from state %d\n", dev->state);
|
|
spin_lock_irqsave(&dev->lock, flags);
|
|
switch (dev->state) {
|
|
case STATE_DEV_SETUP: // VERY odd... host died??
|
|
case STATE_DEV_CONNECTED:
|
|
case STATE_DEV_UNCONNECTED:
|
|
next_event (dev, GADGETFS_SUSPEND);
|
|
ep0_readable (dev);
|
|
/* FALLTHROUGH */
|
|
default:
|
|
break;
|
|
}
|
|
spin_unlock_irqrestore(&dev->lock, flags);
|
|
}
|
|
|
|
static struct usb_gadget_driver gadgetfs_driver = {
|
|
.function = (char *) driver_desc,
|
|
.bind = gadgetfs_bind,
|
|
.unbind = gadgetfs_unbind,
|
|
.setup = gadgetfs_setup,
|
|
.reset = gadgetfs_disconnect,
|
|
.disconnect = gadgetfs_disconnect,
|
|
.suspend = gadgetfs_suspend,
|
|
|
|
.driver = {
|
|
.name = (char *) shortname,
|
|
},
|
|
};
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
/* DEVICE INITIALIZATION
|
|
*
|
|
* fd = open ("/dev/gadget/$CHIP", O_RDWR)
|
|
* status = write (fd, descriptors, sizeof descriptors)
|
|
*
|
|
* That write establishes the device configuration, so the kernel can
|
|
* bind to the controller ... guaranteeing it can handle enumeration
|
|
* at all necessary speeds. Descriptor order is:
|
|
*
|
|
* . message tag (u32, host order) ... for now, must be zero; it
|
|
* would change to support features like multi-config devices
|
|
* . full/low speed config ... all wTotalLength bytes (with interface,
|
|
* class, altsetting, endpoint, and other descriptors)
|
|
* . high speed config ... all descriptors, for high speed operation;
|
|
* this one's optional except for high-speed hardware
|
|
* . device descriptor
|
|
*
|
|
* Endpoints are not yet enabled. Drivers must wait until device
|
|
* configuration and interface altsetting changes create
|
|
* the need to configure (or unconfigure) them.
|
|
*
|
|
* After initialization, the device stays active for as long as that
|
|
* $CHIP file is open. Events must then be read from that descriptor,
|
|
* such as configuration notifications.
|
|
*/
|
|
|
|
static int is_valid_config(struct usb_config_descriptor *config,
|
|
unsigned int total)
|
|
{
|
|
return config->bDescriptorType == USB_DT_CONFIG
|
|
&& config->bLength == USB_DT_CONFIG_SIZE
|
|
&& total >= USB_DT_CONFIG_SIZE
|
|
&& config->bConfigurationValue != 0
|
|
&& (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
|
|
&& (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
|
|
/* FIXME if gadget->is_otg, _must_ include an otg descriptor */
|
|
/* FIXME check lengths: walk to end */
|
|
}
|
|
|
|
static ssize_t
|
|
dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
|
|
{
|
|
struct dev_data *dev = fd->private_data;
|
|
ssize_t value = len, length = len;
|
|
unsigned total;
|
|
u32 tag;
|
|
char *kbuf;
|
|
|
|
spin_lock_irq(&dev->lock);
|
|
if (dev->state > STATE_DEV_OPENED) {
|
|
value = ep0_write(fd, buf, len, ptr);
|
|
spin_unlock_irq(&dev->lock);
|
|
return value;
|
|
}
|
|
spin_unlock_irq(&dev->lock);
|
|
|
|
if ((len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) ||
|
|
(len > PAGE_SIZE * 4))
|
|
return -EINVAL;
|
|
|
|
/* we might need to change message format someday */
|
|
if (copy_from_user (&tag, buf, 4))
|
|
return -EFAULT;
|
|
if (tag != 0)
|
|
return -EINVAL;
|
|
buf += 4;
|
|
length -= 4;
|
|
|
|
kbuf = memdup_user(buf, length);
|
|
if (IS_ERR(kbuf))
|
|
return PTR_ERR(kbuf);
|
|
|
|
spin_lock_irq (&dev->lock);
|
|
value = -EINVAL;
|
|
if (dev->buf) {
|
|
kfree(kbuf);
|
|
goto fail;
|
|
}
|
|
dev->buf = kbuf;
|
|
|
|
/* full or low speed config */
|
|
dev->config = (void *) kbuf;
|
|
total = le16_to_cpu(dev->config->wTotalLength);
|
|
if (!is_valid_config(dev->config, total) ||
|
|
total > length - USB_DT_DEVICE_SIZE)
|
|
goto fail;
|
|
kbuf += total;
|
|
length -= total;
|
|
|
|
/* optional high speed config */
|
|
if (kbuf [1] == USB_DT_CONFIG) {
|
|
dev->hs_config = (void *) kbuf;
|
|
total = le16_to_cpu(dev->hs_config->wTotalLength);
|
|
if (!is_valid_config(dev->hs_config, total) ||
|
|
total > length - USB_DT_DEVICE_SIZE)
|
|
goto fail;
|
|
kbuf += total;
|
|
length -= total;
|
|
} else {
|
|
dev->hs_config = NULL;
|
|
}
|
|
|
|
/* could support multiple configs, using another encoding! */
|
|
|
|
/* device descriptor (tweaked for paranoia) */
|
|
if (length != USB_DT_DEVICE_SIZE)
|
|
goto fail;
|
|
dev->dev = (void *)kbuf;
|
|
if (dev->dev->bLength != USB_DT_DEVICE_SIZE
|
|
|| dev->dev->bDescriptorType != USB_DT_DEVICE
|
|
|| dev->dev->bNumConfigurations != 1)
|
|
goto fail;
|
|
dev->dev->bcdUSB = cpu_to_le16 (0x0200);
|
|
|
|
/* triggers gadgetfs_bind(); then we can enumerate. */
|
|
spin_unlock_irq (&dev->lock);
|
|
if (dev->hs_config)
|
|
gadgetfs_driver.max_speed = USB_SPEED_HIGH;
|
|
else
|
|
gadgetfs_driver.max_speed = USB_SPEED_FULL;
|
|
|
|
value = usb_gadget_probe_driver(&gadgetfs_driver);
|
|
if (value != 0) {
|
|
kfree (dev->buf);
|
|
dev->buf = NULL;
|
|
} else {
|
|
/* at this point "good" hardware has for the first time
|
|
* let the USB the host see us. alternatively, if users
|
|
* unplug/replug that will clear all the error state.
|
|
*
|
|
* note: everything running before here was guaranteed
|
|
* to choke driver model style diagnostics. from here
|
|
* on, they can work ... except in cleanup paths that
|
|
* kick in after the ep0 descriptor is closed.
|
|
*/
|
|
value = len;
|
|
dev->gadget_registered = true;
|
|
}
|
|
return value;
|
|
|
|
fail:
|
|
spin_unlock_irq (&dev->lock);
|
|
pr_debug ("%s: %s fail %zd, %p\n", shortname, __func__, value, dev);
|
|
kfree (dev->buf);
|
|
dev->buf = NULL;
|
|
return value;
|
|
}
|
|
|
|
static int
|
|
dev_open (struct inode *inode, struct file *fd)
|
|
{
|
|
struct dev_data *dev = inode->i_private;
|
|
int value = -EBUSY;
|
|
|
|
spin_lock_irq(&dev->lock);
|
|
if (dev->state == STATE_DEV_DISABLED) {
|
|
dev->ev_next = 0;
|
|
dev->state = STATE_DEV_OPENED;
|
|
fd->private_data = dev;
|
|
get_dev (dev);
|
|
value = 0;
|
|
}
|
|
spin_unlock_irq(&dev->lock);
|
|
return value;
|
|
}
|
|
|
|
static const struct file_operations ep0_operations = {
|
|
.llseek = no_llseek,
|
|
|
|
.open = dev_open,
|
|
.read = ep0_read,
|
|
.write = dev_config,
|
|
.fasync = ep0_fasync,
|
|
.poll = ep0_poll,
|
|
.unlocked_ioctl = dev_ioctl,
|
|
.release = dev_release,
|
|
};
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
/* FILESYSTEM AND SUPERBLOCK OPERATIONS
|
|
*
|
|
* Mounting the filesystem creates a controller file, used first for
|
|
* device configuration then later for event monitoring.
|
|
*/
|
|
|
|
|
|
/* FIXME PAM etc could set this security policy without mount options
|
|
* if epfiles inherited ownership and permissons from ep0 ...
|
|
*/
|
|
|
|
static unsigned default_uid;
|
|
static unsigned default_gid;
|
|
static unsigned default_perm = S_IRUSR | S_IWUSR;
|
|
|
|
module_param (default_uid, uint, 0644);
|
|
module_param (default_gid, uint, 0644);
|
|
module_param (default_perm, uint, 0644);
|
|
|
|
|
|
static struct inode *
|
|
gadgetfs_make_inode (struct super_block *sb,
|
|
void *data, const struct file_operations *fops,
|
|
int mode)
|
|
{
|
|
struct inode *inode = new_inode (sb);
|
|
|
|
if (inode) {
|
|
inode->i_ino = get_next_ino();
|
|
inode->i_mode = mode;
|
|
inode->i_uid = make_kuid(&init_user_ns, default_uid);
|
|
inode->i_gid = make_kgid(&init_user_ns, default_gid);
|
|
inode->i_atime = inode->i_mtime = inode->i_ctime
|
|
= current_time(inode);
|
|
inode->i_private = data;
|
|
inode->i_fop = fops;
|
|
}
|
|
return inode;
|
|
}
|
|
|
|
/* creates in fs root directory, so non-renamable and non-linkable.
|
|
* so inode and dentry are paired, until device reconfig.
|
|
*/
|
|
static struct dentry *
|
|
gadgetfs_create_file (struct super_block *sb, char const *name,
|
|
void *data, const struct file_operations *fops)
|
|
{
|
|
struct dentry *dentry;
|
|
struct inode *inode;
|
|
|
|
dentry = d_alloc_name(sb->s_root, name);
|
|
if (!dentry)
|
|
return NULL;
|
|
|
|
inode = gadgetfs_make_inode (sb, data, fops,
|
|
S_IFREG | (default_perm & S_IRWXUGO));
|
|
if (!inode) {
|
|
dput(dentry);
|
|
return NULL;
|
|
}
|
|
d_add (dentry, inode);
|
|
return dentry;
|
|
}
|
|
|
|
static const struct super_operations gadget_fs_operations = {
|
|
.statfs = simple_statfs,
|
|
.drop_inode = generic_delete_inode,
|
|
};
|
|
|
|
static int
|
|
gadgetfs_fill_super (struct super_block *sb, struct fs_context *fc)
|
|
{
|
|
struct inode *inode;
|
|
struct dev_data *dev;
|
|
|
|
if (the_device)
|
|
return -ESRCH;
|
|
|
|
CHIP = usb_get_gadget_udc_name();
|
|
if (!CHIP)
|
|
return -ENODEV;
|
|
|
|
/* superblock */
|
|
sb->s_blocksize = PAGE_SIZE;
|
|
sb->s_blocksize_bits = PAGE_SHIFT;
|
|
sb->s_magic = GADGETFS_MAGIC;
|
|
sb->s_op = &gadget_fs_operations;
|
|
sb->s_time_gran = 1;
|
|
|
|
/* root inode */
|
|
inode = gadgetfs_make_inode (sb,
|
|
NULL, &simple_dir_operations,
|
|
S_IFDIR | S_IRUGO | S_IXUGO);
|
|
if (!inode)
|
|
goto Enomem;
|
|
inode->i_op = &simple_dir_inode_operations;
|
|
if (!(sb->s_root = d_make_root (inode)))
|
|
goto Enomem;
|
|
|
|
/* the ep0 file is named after the controller we expect;
|
|
* user mode code can use it for sanity checks, like we do.
|
|
*/
|
|
dev = dev_new ();
|
|
if (!dev)
|
|
goto Enomem;
|
|
|
|
dev->sb = sb;
|
|
dev->dentry = gadgetfs_create_file(sb, CHIP, dev, &ep0_operations);
|
|
if (!dev->dentry) {
|
|
put_dev(dev);
|
|
goto Enomem;
|
|
}
|
|
|
|
/* other endpoint files are available after hardware setup,
|
|
* from binding to a controller.
|
|
*/
|
|
the_device = dev;
|
|
return 0;
|
|
|
|
Enomem:
|
|
return -ENOMEM;
|
|
}
|
|
|
|
/* "mount -t gadgetfs path /dev/gadget" ends up here */
|
|
static int gadgetfs_get_tree(struct fs_context *fc)
|
|
{
|
|
return get_tree_single(fc, gadgetfs_fill_super);
|
|
}
|
|
|
|
static const struct fs_context_operations gadgetfs_context_ops = {
|
|
.get_tree = gadgetfs_get_tree,
|
|
};
|
|
|
|
static int gadgetfs_init_fs_context(struct fs_context *fc)
|
|
{
|
|
fc->ops = &gadgetfs_context_ops;
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
gadgetfs_kill_sb (struct super_block *sb)
|
|
{
|
|
kill_litter_super (sb);
|
|
if (the_device) {
|
|
put_dev (the_device);
|
|
the_device = NULL;
|
|
}
|
|
kfree(CHIP);
|
|
CHIP = NULL;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
static struct file_system_type gadgetfs_type = {
|
|
.owner = THIS_MODULE,
|
|
.name = shortname,
|
|
.init_fs_context = gadgetfs_init_fs_context,
|
|
.kill_sb = gadgetfs_kill_sb,
|
|
};
|
|
MODULE_ALIAS_FS("gadgetfs");
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
static int __init init (void)
|
|
{
|
|
int status;
|
|
|
|
status = register_filesystem (&gadgetfs_type);
|
|
if (status == 0)
|
|
pr_info ("%s: %s, version " DRIVER_VERSION "\n",
|
|
shortname, driver_desc);
|
|
return status;
|
|
}
|
|
module_init (init);
|
|
|
|
static void __exit cleanup (void)
|
|
{
|
|
pr_debug ("unregister %s\n", shortname);
|
|
unregister_filesystem (&gadgetfs_type);
|
|
}
|
|
module_exit (cleanup);
|
|
|