hollalinux
/
linux-sg2042
mirror of https://github.com/sophgo/linux-riscv.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

[PATCH] scx200_gpio: 1 cdev for N minors: cleanup, prep 

this patch is mostly cleanup of scx200_gpio :
- drop #include <linux/config.h>
- s/DEVNAME/DRVNAME/    apparently a convention
- replace variable num_pins with  #define MAX_PINS
- s/dev/devid/   to clarify that its a dev_t, not a struct device dev.
- move devid = MKDEV(major,0)  into branch where its needed.

2 minor 'changes' :

- reduced MAX_PINS from 64 to 32.  Ive never tested other pins, and
  theyre all multiplexed with other functions, some of which may be in use
  on my soekris 4801, so I dont know what testing should yield.

- +EXPORT_SYMBOL(scx200_access);

  This exposes the driver's vtable, which another driver can use along
  with #include <linux/nsc_gpio.h>, to manipulate a gpio-pin.

Signed-off-by  Jim Cromie <jim.cromie@gmail.com>

Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Jim Cromie 2006-07-14 00:24:16 -07:00 committed by Linus Torvalds
parent 6bc02d8412
commit ae2d1f2f5b
1 changed files with 19 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
drivers/char/scx200_gpio.c
View File

@ -5,7 +5,6 @@
Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> */
#include <linux/config.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/module.h>
@ -22,19 +21,20 @@
#include <linux/scx200_gpio.h>
#include <linux/nsc_gpio.h>
#define NAME "scx200_gpio"
#define DEVNAME NAME
#define DRVNAME "scx200_gpio"
static struct platform_device *pdev;
MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
MODULE_DESCRIPTION("NatSemi SCx200 GPIO Pin Driver");
MODULE_DESCRIPTION("NatSemi/AMD SCx200 GPIO Pin Driver");
MODULE_LICENSE("GPL");
static int major = 0; /* default to dynamic major */
module_param(major, int, 0);
MODULE_PARM_DESC(major, "Major device number");
#define MAX_PINS 32 /* 64 later, when known ok */
struct nsc_gpio_ops scx200_access = {
.owner = THIS_MODULE,
.gpio_config = scx200_gpio_configure,
@ -46,13 +46,14 @@ struct nsc_gpio_ops scx200_access = {
.gpio_change = scx200_gpio_change,
.gpio_current = scx200_gpio_current
};
EXPORT_SYMBOL(scx200_access);
static int scx200_gpio_open(struct inode *inode, struct file *file)
{
unsigned m = iminor(inode);
file->private_data = &scx200_access;
if (m > 63)
if (m >= MAX_PINS)
return -EINVAL;
return nonseekable_open(inode, file);
}
@ -72,20 +73,19 @@ static const struct file_operations scx200_gpio_fops = {
};
struct cdev *scx200_devices;
static int num_pins = 32;
static int __init scx200_gpio_init(void)
{
int rc, i;
dev_t dev = MKDEV(major, 0);
dev_t devid;
if (!scx200_gpio_present()) {
printk(KERN_ERR NAME ": no SCx200 gpio present\n");
printk(KERN_ERR DRVNAME ": no SCx200 gpio present\n");
return -ENODEV;
}
/* support dev_dbg() with pdev->dev */
pdev = platform_device_alloc(DEVNAME, 0);
pdev = platform_device_alloc(DRVNAME, 0);
if (!pdev)
return -ENOMEM;
@ -96,22 +96,23 @@ static int __init scx200_gpio_init(void)
/* nsc_gpio uses dev_dbg(), so needs this */
scx200_access.dev = &pdev->dev;
if (major)
rc = register_chrdev_region(dev, num_pins, "scx200_gpio");
else {
rc = alloc_chrdev_region(&dev, 0, num_pins, "scx200_gpio");
major = MAJOR(dev);
if (major) {
devid = MKDEV(major, 0);
rc = register_chrdev_region(devid, MAX_PINS, "scx200_gpio");
} else {
rc = alloc_chrdev_region(&devid, 0, MAX_PINS, "scx200_gpio");
major = MAJOR(devid);
}
if (rc < 0) {
dev_err(&pdev->dev, "SCx200 chrdev_region err: %d\n", rc);
goto undo_platform_device_add;
}
scx200_devices = kzalloc(num_pins * sizeof(struct cdev), GFP_KERNEL);
scx200_devices = kzalloc(MAX_PINS * sizeof(struct cdev), GFP_KERNEL);
if (!scx200_devices) {
rc = -ENOMEM;
goto undo_chrdev_region;
}
for (i = 0; i < num_pins; i++) {
for (i = 0; i < MAX_PINS; i++) {
struct cdev *cdev = &scx200_devices[i];
cdev_init(cdev, &scx200_gpio_fops);
cdev->owner = THIS_MODULE;
@ -124,7 +125,7 @@ static int __init scx200_gpio_init(void)
return 0; /* succeed */
undo_chrdev_region:
unregister_chrdev_region(dev, num_pins);
unregister_chrdev_region(devid, MAX_PINS);
undo_platform_device_add:
platform_device_del(pdev);
undo_malloc:
@ -136,9 +137,8 @@ undo_malloc:
static void __exit scx200_gpio_cleanup(void)
{
kfree(scx200_devices);
unregister_chrdev_region(MKDEV(major, 0), num_pins);
unregister_chrdev_region(MKDEV(major, 0), MAX_PINS);
platform_device_unregister(pdev);
/* kfree(pdev); */
}
module_init(scx200_gpio_init);