diff options
| author | David Härdeman <david@hardeman.nu> | 2017-06-25 09:32:05 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2017-10-04 14:03:21 -0300 |
| commit | 46c8f4771154eb0dc21f5f2bc2640a33e8fe1d02 (patch) | |
| tree | ceb3f9342ccff3441735eddd94bdb54a891b2508 /drivers/media/rc | |
| parent | 3381b779a736f4908a64b603ce339ab067e01de7 (diff) | |
[media] media: lirc_dev: use an IDA instead of an array to keep track of registered devices
Using the kernel-provided IDA simplifies the code and makes it possible
to remove the lirc_dev_lock mutex.
Signed-off-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'drivers/media/rc')
| -rw-r--r-- | drivers/media/rc/lirc_dev.c | 36 |
1 files changed, 12 insertions, 24 deletions
diff --git a/drivers/media/rc/lirc_dev.c b/drivers/media/rc/lirc_dev.c index c83fffec0681..a2c5ed0181c1 100644 --- a/drivers/media/rc/lirc_dev.c +++ b/drivers/media/rc/lirc_dev.c @@ -24,6 +24,7 @@ #include <linux/mutex.h> #include <linux/device.h> #include <linux/cdev.h> +#include <linux/idr.h> #include <media/rc-core.h> #include <media/lirc.h> @@ -46,10 +47,9 @@ struct irctl { struct cdev cdev; }; -/* This mutex protects the irctls array */ -static DEFINE_MUTEX(lirc_dev_lock); - -static struct irctl *irctls[MAX_IRCTL_DEVICES]; +/* Used to keep track of allocated lirc devices */ +#define LIRC_MAX_DEVICES 256 +static DEFINE_IDA(lirc_ida); /* Only used for sysfs but defined to void otherwise */ static struct class *lirc_class; @@ -69,9 +69,6 @@ static void lirc_release(struct device *ld) { struct irctl *ir = container_of(ld, struct irctl, dev); - mutex_lock(&lirc_dev_lock); - irctls[ir->d.minor] = NULL; - mutex_unlock(&lirc_dev_lock); lirc_free_buffer(ir); kfree(ir); } @@ -109,7 +106,7 @@ out: int lirc_register_driver(struct lirc_driver *d) { struct irctl *ir; - unsigned int minor; + int minor; int err; if (!d) { @@ -171,28 +168,17 @@ int lirc_register_driver(struct lirc_driver *d) d->rbuf = ir->buf; } - mutex_lock(&lirc_dev_lock); - - /* find first free slot for driver */ - for (minor = 0; minor < MAX_IRCTL_DEVICES; minor++) - if (!irctls[minor]) - break; - - if (minor == MAX_IRCTL_DEVICES) { - dev_err(d->dev, "no free slots for drivers!\n"); - mutex_unlock(&lirc_dev_lock); + minor = ida_simple_get(&lirc_ida, 0, LIRC_MAX_DEVICES, GFP_KERNEL); + if (minor < 0) { lirc_free_buffer(ir); kfree(ir); - return -ENOMEM; + return minor; } - irctls[minor] = ir; d->irctl = ir; d->minor = minor; ir->d.minor = minor; - mutex_unlock(&lirc_dev_lock); - device_initialize(&ir->dev); ir->dev.devt = MKDEV(MAJOR(lirc_base_dev), ir->d.minor); ir->dev.class = lirc_class; @@ -206,6 +192,7 @@ int lirc_register_driver(struct lirc_driver *d) err = cdev_device_add(&ir->cdev, &ir->dev); if (err) { + ida_simple_remove(&lirc_ida, minor); put_device(&ir->dev); return err; } @@ -244,6 +231,7 @@ void lirc_unregister_driver(struct lirc_driver *d) mutex_unlock(&ir->mutex); + ida_simple_remove(&lirc_ida, d->minor); put_device(&ir->dev); } EXPORT_SYMBOL(lirc_unregister_driver); @@ -540,7 +528,7 @@ static int __init lirc_dev_init(void) return PTR_ERR(lirc_class); } - retval = alloc_chrdev_region(&lirc_base_dev, 0, MAX_IRCTL_DEVICES, + retval = alloc_chrdev_region(&lirc_base_dev, 0, LIRC_MAX_DEVICES, "BaseRemoteCtl"); if (retval) { class_destroy(lirc_class); @@ -557,7 +545,7 @@ static int __init lirc_dev_init(void) static void __exit lirc_dev_exit(void) { class_destroy(lirc_class); - unregister_chrdev_region(lirc_base_dev, MAX_IRCTL_DEVICES); + unregister_chrdev_region(lirc_base_dev, LIRC_MAX_DEVICES); pr_info("module unloaded\n"); } |