From eefdbec1ea8b7093d2c09d1825f68438701723cf Mon Sep 17 00:00:00 2001 From: Jussi Kivilinna Date: Sat, 12 Feb 2011 20:43:32 +0200 Subject: [PATCH] zd1211rw: use async urb for write command Writing beacon to device happen through multiple write command calls. zd_usb_iowrite16v uses synchronous urb call and with multiple write commands in row causes high CPU usage. This patch makes zd_usb_iowrite16v use asynchronous urb submit within zd_usb.c. zd_usb_iowrite16v_async_start is used to initiate writing multiple commands to device using zd_usb_iowrite16v_async. Each URB is delayed and submitted to device by next zd_usb_iowrite16v_async call or by call to zd_usb_iowrite16v_async_end. URBs submitted by zd_usb_iowrite16v_async have URB_NO_INTERRUPT set and last URB send by zd_usb_iowrite16v_async_end does not. This lower CPU usage when doing writes that require multiple URBs. Signed-off-by: Jussi Kivilinna Signed-off-by: John W. Linville --- drivers/net/wireless/zd1211rw/zd_usb.c | 162 +++++++++++++++++++++---- drivers/net/wireless/zd1211rw/zd_usb.h | 5 +- 2 files changed, 142 insertions(+), 25 deletions(-) diff --git a/drivers/net/wireless/zd1211rw/zd_usb.c b/drivers/net/wireless/zd1211rw/zd_usb.c index 7346512158e8..c98f6e7eed3d 100644 --- a/drivers/net/wireless/zd1211rw/zd_usb.c +++ b/drivers/net/wireless/zd1211rw/zd_usb.c @@ -1156,6 +1156,7 @@ void zd_usb_init(struct zd_usb *usb, struct ieee80211_hw *hw, memset(usb, 0, sizeof(*usb)); usb->intf = usb_get_intf(intf); usb_set_intfdata(usb->intf, hw); + init_usb_anchor(&usb->submitted_cmds); init_usb_interrupt(usb); init_usb_tx(usb); init_usb_rx(usb); @@ -1663,13 +1664,104 @@ error: return r; } -int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs, - unsigned int count) +static void iowrite16v_urb_complete(struct urb *urb) +{ + struct zd_usb *usb = urb->context; + + if (urb->status && !usb->cmd_error) + usb->cmd_error = urb->status; +} + +static int zd_submit_waiting_urb(struct zd_usb *usb, bool last) +{ + int r; + struct urb *urb = usb->urb_async_waiting; + + if (!urb) + return 0; + + usb->urb_async_waiting = NULL; + + if (!last) + urb->transfer_flags |= URB_NO_INTERRUPT; + + usb_anchor_urb(urb, &usb->submitted_cmds); + r = usb_submit_urb(urb, GFP_KERNEL); + if (r) { + usb_unanchor_urb(urb); + dev_dbg_f(zd_usb_dev(usb), + "error in usb_submit_urb(). Error number %d\n", r); + goto error; + } + + /* fall-through with r == 0 */ +error: + usb_free_urb(urb); + return r; +} + +static void zd_usb_iowrite16v_async_start(struct zd_usb *usb) +{ + ZD_ASSERT(usb_anchor_empty(&usb->submitted_cmds)); + ZD_ASSERT(usb->urb_async_waiting == NULL); + ZD_ASSERT(!usb->in_async); + + ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex)); + + usb->in_async = 1; + usb->cmd_error = 0; + usb->urb_async_waiting = NULL; +} + +static int zd_usb_iowrite16v_async_end(struct zd_usb *usb, unsigned int timeout) +{ + int r; + + ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex)); + ZD_ASSERT(usb->in_async); + + /* Submit last iowrite16v URB */ + r = zd_submit_waiting_urb(usb, true); + if (r) { + dev_dbg_f(zd_usb_dev(usb), + "error in zd_submit_waiting_usb(). " + "Error number %d\n", r); + + usb_kill_anchored_urbs(&usb->submitted_cmds); + goto error; + } + + if (timeout) + timeout = usb_wait_anchor_empty_timeout(&usb->submitted_cmds, + timeout); + if (!timeout) { + usb_kill_anchored_urbs(&usb->submitted_cmds); + if (usb->cmd_error == -ENOENT) { + dev_dbg_f(zd_usb_dev(usb), "timed out"); + r = -ETIMEDOUT; + goto error; + } + } + + r = usb->cmd_error; +error: + usb->in_async = 0; + return r; +} + +static int zd_usb_iowrite16v_async(struct zd_usb *usb, + const struct zd_ioreq16 *ioreqs, + unsigned int count) { int r; struct usb_device *udev; struct usb_req_write_regs *req = NULL; - int i, req_len, actual_req_len; + int i, req_len; + struct urb *urb; + struct usb_host_endpoint *ep; + + ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex)); + ZD_ASSERT(usb->in_async); if (count == 0) return 0; @@ -1685,17 +1777,23 @@ int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs, return -EWOULDBLOCK; } - ZD_ASSERT(mutex_is_locked(&zd_usb_to_chip(usb)->mutex)); - BUILD_BUG_ON(sizeof(struct usb_req_write_regs) + - USB_MAX_IOWRITE16_COUNT * sizeof(struct reg_data) > - sizeof(usb->req_buf)); - BUG_ON(sizeof(struct usb_req_write_regs) + - count * sizeof(struct reg_data) > - sizeof(usb->req_buf)); + udev = zd_usb_to_usbdev(usb); + + ep = usb_pipe_endpoint(udev, usb_sndintpipe(udev, EP_REGS_OUT)); + if (!ep) + return -ENOENT; + + urb = usb_alloc_urb(0, GFP_KERNEL); + if (!urb) + return -ENOMEM; req_len = sizeof(struct usb_req_write_regs) + count * sizeof(struct reg_data); - req = (void *)usb->req_buf; + req = kmalloc(req_len, GFP_KERNEL); + if (!req) { + r = -ENOMEM; + goto error; + } req->id = cpu_to_le16(USB_REQ_WRITE_REGS); for (i = 0; i < count; i++) { @@ -1704,28 +1802,44 @@ int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs, rw->value = cpu_to_le16(ioreqs[i].value); } - udev = zd_usb_to_usbdev(usb); - r = usb_interrupt_msg(udev, usb_sndintpipe(udev, EP_REGS_OUT), - req, req_len, &actual_req_len, 50 /* ms */); + usb_fill_int_urb(urb, udev, usb_sndintpipe(udev, EP_REGS_OUT), + req, req_len, iowrite16v_urb_complete, usb, + ep->desc.bInterval); + urb->transfer_flags |= URB_FREE_BUFFER | URB_SHORT_NOT_OK; + + /* Submit previous URB */ + r = zd_submit_waiting_urb(usb, false); if (r) { dev_dbg_f(zd_usb_dev(usb), - "error in usb_interrupt_msg(). Error number %d\n", r); - goto error; - } - if (req_len != actual_req_len) { - dev_dbg_f(zd_usb_dev(usb), - "error in usb_interrupt_msg()" - " req_len %d != actual_req_len %d\n", - req_len, actual_req_len); - r = -EIO; + "error in zd_submit_waiting_usb(). " + "Error number %d\n", r); goto error; } - /* FALL-THROUGH with r == 0 */ + /* Delay submit so that URB_NO_INTERRUPT flag can be set for all URBs + * of currect batch except for very last. + */ + usb->urb_async_waiting = urb; + return 0; error: + usb_free_urb(urb); return r; } +int zd_usb_iowrite16v(struct zd_usb *usb, const struct zd_ioreq16 *ioreqs, + unsigned int count) +{ + int r; + + zd_usb_iowrite16v_async_start(usb); + r = zd_usb_iowrite16v_async(usb, ioreqs, count); + if (r) { + zd_usb_iowrite16v_async_end(usb, 0); + return r; + } + return zd_usb_iowrite16v_async_end(usb, 50 /* ms */); +} + int zd_usb_rfwrite(struct zd_usb *usb, u32 value, u8 bits) { int r; diff --git a/drivers/net/wireless/zd1211rw/zd_usb.h b/drivers/net/wireless/zd1211rw/zd_usb.h index 2d688f48a34c..929142692063 100644 --- a/drivers/net/wireless/zd1211rw/zd_usb.h +++ b/drivers/net/wireless/zd1211rw/zd_usb.h @@ -217,8 +217,11 @@ struct zd_usb { struct zd_usb_rx rx; struct zd_usb_tx tx; struct usb_interface *intf; + struct usb_anchor submitted_cmds; + struct urb *urb_async_waiting; + int cmd_error; u8 req_buf[64]; /* zd_usb_iowrite16v needs 62 bytes */ - u8 is_zd1211b:1, initialized:1, was_running:1; + u8 is_zd1211b:1, initialized:1, was_running:1, in_async:1; }; #define zd_usb_dev(usb) (&usb->intf->dev)