Jim Cromie wrote:
Im trying to update scx200_gpio to properly use the 2.6 api
(and thus learn it)
attached patch does following:
- register chrdev-region for 32 devices, (or alloc-chrdev-region)
- allocate array of 32 cdevs,
- initialize each cdev in scx200_gpio_init()
with gpio_fops, and major, minors
oof. attaching now
If I set up file->private_data with the right info, then the dev is
obtainable.
is it ?
diff -ruNp -X dontdiff -X exclude-diffs C-1/drivers/char/scx200_gpio.c C-2/drivers/char/scx200_gpio.c
--- C-1/drivers/char/scx200_gpio.c 2006-02-01 14:09:40.000000000 -0700
+++ C-2/drivers/char/scx200_gpio.c 2006-02-01 14:11:50.000000000 -0700
@@ -14,6 +14,9 @@
#include <asm/uaccess.h>
#include <asm/io.h>
+#include <linux/types.h>
+#include <linux/cdev.h>
+
#include <linux/scx200_gpio.h>
#define NAME "scx200_gpio"
@@ -26,6 +29,8 @@ static int major = 0; /* default to dyn
module_param(major, int, 0);
MODULE_PARM_DESC(major, "Major device number");
+extern void scx200_gpio_dump(unsigned index);
+
static ssize_t scx200_gpio_write(struct file *file, const char __user * data,
size_t len, loff_t * ppos)
{
@@ -109,33 +114,57 @@ static struct file_operations scx200_gpi
.release = scx200_gpio_release,
};
+struct cdev *scx200_devices;
+int num_devs = 32;
+
static int __init scx200_gpio_init(void)
{
- int r;
+ int rc, i;
+ dev_t dev = MKDEV(major, 0);
printk(KERN_DEBUG NAME ": NatSemi SCx200 GPIO Driver\n");
if (!scx200_gpio_present()) {
- printk(KERN_ERR NAME ": no SCx200 gpio pins available\n");
+ printk(KERN_ERR NAME ": no SCx200 gpio present\n");
return -ENODEV;
}
-
- r = register_chrdev(major, NAME, &scx200_gpio_fops);
- if (r < 0) {
- printk(KERN_ERR NAME ": unable to register character device\n");
- return r;
- }
- if (!major) {
- major = r;
- printk(KERN_DEBUG NAME ": got dynamic major %d\n", major);
+ if (major)
+ rc = register_chrdev_region(dev, num_devs, "scx200_gpio");
+ else {
+ rc = alloc_chrdev_region(&dev, 0, num_devs, "scx200_gpio");
+ major = MAJOR(dev);
+ }
+ if (rc < 0) {
+ printk(KERN_ERR NAME ": SCx200 chrdev_region failure %d\n", rc);
+ return rc;
+ }
+ scx200_devices = kzalloc(num_devs * sizeof(struct cdev), GFP_KERNEL);
+ if (!scx200_devices) {
+ rc = -ENOMEM;
+ goto fail_malloc;
+ }
+ for (i = 0; i < num_devs; i++) {
+ struct cdev *cdev = &scx200_devices[i];
+ cdev_init(cdev, &scx200_gpio_fops);
+ cdev->owner = THIS_MODULE;
+ cdev->ops = &scx200_gpio_fops;
+ rc = cdev_add(cdev, MKDEV(major, i), 1);
+ /* Fail gracefully if need be */
+ if (rc)
+ printk(KERN_ERR NAME "Error %d on minor %d", rc, i);
}
- return 0;
+ return 0; /* succeed */
+
+ fail_malloc:
+ unregister_chrdev_region(dev, num_devs);
+ return rc;
}
static void __exit scx200_gpio_cleanup(void)
{
- unregister_chrdev(major, NAME);
+ kfree(scx200_devices);
+ unregister_chrdev_region(MKDEV(major, 0), num_devs);
}
module_init(scx200_gpio_init);
