-/* linux/drivers/char/scx200_gpio.c
+/* linux/drivers/char/scx200_gpio.c
National Semiconductor SCx200 GPIO driver. Allows a user space
process to play with the GPIO pins.
Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> */
-#include <linux/device.h>
+#include <linux/config.h>
#include <linux/fs.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/init.h>
-#include <linux/platform_device.h>
#include <asm/uaccess.h>
#include <asm/io.h>
-#include <linux/types.h>
-#include <linux/cdev.h>
-
#include <linux/scx200_gpio.h>
-#include <linux/nsc_gpio.h>
-
-#define DRVNAME "scx200_gpio"
-static struct platform_device *pdev;
+#define NAME "scx200_gpio"
MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
-MODULE_DESCRIPTION("NatSemi/AMD SCx200 GPIO Pin Driver");
+MODULE_DESCRIPTION("NatSemi 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 */
+static ssize_t scx200_gpio_write(struct file *file, const char __user *data,
+ size_t len, loff_t *ppos)
+{
+ unsigned m = iminor(file->f_dentry->d_inode);
+ size_t i;
+
+ for (i = 0; i < len; ++i) {
+ char c;
+ if (get_user(c, data+i))
+ return -EFAULT;
+ switch (c)
+ {
+ case '0':
+ scx200_gpio_set(m, 0);
+ break;
+ case '1':
+ scx200_gpio_set(m, 1);
+ break;
+ case 'O':
+ printk(KERN_INFO NAME ": GPIO%d output enabled\n", m);
+ scx200_gpio_configure(m, ~1, 1);
+ break;
+ case 'o':
+ printk(KERN_INFO NAME ": GPIO%d output disabled\n", m);
+ scx200_gpio_configure(m, ~1, 0);
+ break;
+ case 'T':
+ printk(KERN_INFO NAME ": GPIO%d output is push pull\n", m);
+ scx200_gpio_configure(m, ~2, 2);
+ break;
+ case 't':
+ printk(KERN_INFO NAME ": GPIO%d output is open drain\n", m);
+ scx200_gpio_configure(m, ~2, 0);
+ break;
+ case 'P':
+ printk(KERN_INFO NAME ": GPIO%d pull up enabled\n", m);
+ scx200_gpio_configure(m, ~4, 4);
+ break;
+ case 'p':
+ printk(KERN_INFO NAME ": GPIO%d pull up disabled\n", m);
+ scx200_gpio_configure(m, ~4, 0);
+ break;
+ }
+ }
-struct nsc_gpio_ops scx200_gpio_ops = {
- .owner = THIS_MODULE,
- .gpio_config = scx200_gpio_configure,
- .gpio_dump = nsc_gpio_dump,
- .gpio_get = scx200_gpio_get,
- .gpio_set = scx200_gpio_set,
- .gpio_change = scx200_gpio_change,
- .gpio_current = scx200_gpio_current
-};
-EXPORT_SYMBOL(scx200_gpio_ops);
+ return len;
+}
+
+static ssize_t scx200_gpio_read(struct file *file, char __user *buf,
+ size_t len, loff_t *ppos)
+{
+ unsigned m = iminor(file->f_dentry->d_inode);
+ int value;
+
+ value = scx200_gpio_get(m);
+ if (put_user(value ? '1' : '0', buf))
+ return -EFAULT;
+
+ return 1;
+}
static int scx200_gpio_open(struct inode *inode, struct file *file)
{
unsigned m = iminor(inode);
- file->private_data = &scx200_gpio_ops;
-
- if (m >= MAX_PINS)
+ if (m > 63)
return -EINVAL;
return nonseekable_open(inode, file);
}
return 0;
}
-static const struct file_operations scx200_gpio_fileops = {
+
+static struct file_operations scx200_gpio_fops = {
.owner = THIS_MODULE,
- .write = nsc_gpio_write,
- .read = nsc_gpio_read,
+ .write = scx200_gpio_write,
+ .read = scx200_gpio_read,
.open = scx200_gpio_open,
.release = scx200_gpio_release,
};
-struct cdev scx200_gpio_cdev; /* use 1 cdev for all pins */
-
static int __init scx200_gpio_init(void)
{
- int rc;
- dev_t devid;
+ int r;
+
+ printk(KERN_DEBUG NAME ": NatSemi SCx200 GPIO Driver\n");
if (!scx200_gpio_present()) {
- printk(KERN_ERR DRVNAME ": no SCx200 gpio present\n");
+ printk(KERN_ERR NAME ": no SCx200 gpio pins available\n");
return -ENODEV;
}
- /* support dev_dbg() with pdev->dev */
- pdev = platform_device_alloc(DRVNAME, 0);
- if (!pdev)
- return -ENOMEM;
-
- rc = platform_device_add(pdev);
- if (rc)
- goto undo_malloc;
-
- /* nsc_gpio uses dev_dbg(), so needs this */
- scx200_gpio_ops.dev = &pdev->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);
+ r = register_chrdev(major, NAME, &scx200_gpio_fops);
+ if (r < 0) {
+ printk(KERN_ERR NAME ": unable to register character device\n");
+ return r;
}
- if (rc < 0) {
- dev_err(&pdev->dev, "SCx200 chrdev_region err: %d\n", rc);
- goto undo_platform_device_add;
+ if (!major) {
+ major = r;
+ printk(KERN_DEBUG NAME ": got dynamic major %d\n", major);
}
- cdev_init(&scx200_gpio_cdev, &scx200_gpio_fileops);
- cdev_add(&scx200_gpio_cdev, devid, MAX_PINS);
-
- return 0; /* succeed */
-
-undo_platform_device_add:
- platform_device_del(pdev);
-undo_malloc:
- platform_device_put(pdev);
-
- return rc;
+ return 0;
}
static void __exit scx200_gpio_cleanup(void)
{
- cdev_del(&scx200_gpio_cdev);
- /* cdev_put(&scx200_gpio_cdev); */
-
- unregister_chrdev_region(MKDEV(major, 0), MAX_PINS);
- platform_device_unregister(pdev);
+ unregister_chrdev(major, NAME);
}
module_init(scx200_gpio_init);
module_exit(scx200_gpio_cleanup);
+
+/*
+ Local variables:
+ compile-command: "make -k -C ../.. SUBDIRS=drivers/char modules"
+ c-basic-offset: 8
+ End:
+*/
git://git.onelab.eu / linux-2.6.git / blobdiff