From: Jim Cromie Date: Fri, 14 Jul 2006 07:24:16 +0000 (-0700) Subject: [PATCH] scx200_gpio: 1 cdev for N minors: cleanup, prep X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=ae2d1f2f5b59d00b39283c52dc4ee675397bbacd;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git [PATCH] scx200_gpio: 1 cdev for N minors: cleanup, prep this patch is mostly cleanup of scx200_gpio : - drop #include - 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 , to manipulate a gpio-pin. Signed-off-by Jim Cromie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/char/scx200_gpio.c b/drivers/char/scx200_gpio.c index 425c58719db6..e7665c1ad134 100644 --- a/drivers/char/scx200_gpio.c +++ b/drivers/char/scx200_gpio.c @@ -5,7 +5,6 @@ Copyright (c) 2001,2002 Christer Weinigel */ -#include #include #include #include @@ -22,19 +21,20 @@ #include #include -#define NAME "scx200_gpio" -#define DEVNAME NAME +#define DRVNAME "scx200_gpio" static struct platform_device *pdev; MODULE_AUTHOR("Christer Weinigel "); -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);