scx200_gpio: use 1 cdev for N minors, not N for N

this patch removes the scx200_gpio's cdev-array & ksalloc, replacing it with a single static struct cdev, which is sufficient for all the pins.

cdev_put is commented out since kernel wont link properly with it, and its apparently not needed.

With these patches, this driver continues to work with Chris Boot's leds_48xx driver, which is also new in -mm1.

Signed-off-by Jim Cromie <[email protected]>

---

$ diffstat diff.scx-1-cdev
scx200_gpio.c |   28 ++++++++--------------------
1 files changed, 8 insertions(+), 20 deletions(-)

diff -ruNp -X dontdiff -X exclude-diffs x-1/drivers/char/scx200_gpio.c x-2/drivers/char/scx200_gpio.c
@@ -63,7 +63,6 @@ static int scx200_gpio_release(struct in

	return 0;
}

-
static const struct file_operations scx200_gpio_fops = {
.owner = THIS_MODULE,
.write = nsc_gpio_write,
@@ -72,11 +71,11 @@ static const struct file_operations scx2

	.release = scx200_gpio_release,
};

-struct cdev *scx200_devices;
+struct cdev scx200_gpio_cdev; /* use 1 cdev for all pins */

static int __init scx200_gpio_init(void)
{
- int rc, i;

+	int rc;
	dev_t devid;

	if (!scx200_gpio_present()) {
@@ -107,25 +106,12 @@ static int __init scx200_gpio_init(void)
		dev_err(&pdev->dev, "SCx200 chrdev_region err: %d\n", rc);
		goto undo_platform_device_add;
	}

- scx200_devices = kzalloc(MAX_PINS * sizeof(struct cdev), GFP_KERNEL);
- if (!scx200_devices) {
- rc = -ENOMEM;
- goto undo_chrdev_region;
- }
- for (i = 0; i < MAX_PINS; i++) {
- struct cdev *cdev = &scx200_devices[i];
- cdev_init(cdev, &scx200_gpio_fops);
- cdev->owner = THIS_MODULE;
- rc = cdev_add(cdev, MKDEV(major, i), 1);
- /* tolerate 'minor' errors */
- if (rc)
- dev_err(&pdev->dev, "Error %d on minor %d", rc, i);
- }
+
+ cdev_init(&scx200_gpio_cdev, &scx200_gpio_fops);
+ cdev_add(&scx200_gpio_cdev, devid, MAX_PINS);

	return 0; /* succeed */

-undo_chrdev_region:
- unregister_chrdev_region(devid, MAX_PINS);
undo_platform_device_add:

	platform_device_del(pdev);

undo_malloc:
@@ -136,7 +122,9 @@ undo_malloc:

static void __exit scx200_gpio_cleanup(void)
{
- kfree(scx200_devices);
+ cdev_del(&scx200_gpio_cdev);
+ /* cdev_put(&scx200_gpio_cdev); */
+

	unregister_chrdev_region(MKDEV(major, 0), MAX_PINS);
	platform_device_unregister(pdev);
}