From 88c083a78181c2a0830f55c2a4f4e9f6a4954bd2 Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Tue, 14 Jan 2014 16:27:55 -0300 Subject: [PATCH] upstream: [media] rc-core: reuse device numbers Before changeset d8b4b5822f51e, the remote controller device numbers were released when the device were unregistered. That helped to maintain some sanity, as, when USB devices are replugged, the remote controller would get the same number. Restore the same behaviour. Signed-off-by: Mauro Carvalho Chehab --- drivers/media/rc/rc-main.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c index 893bd1fb..e9841c6 100644 --- a/drivers/media/rc/rc-main.c +++ b/drivers/media/rc/rc-main.c @@ -22,6 +22,10 @@ #include #include "rc-core-priv.h" +/* Bitmap to store allocated device numbers from 0 to IRRCV_NUM_DEVICES - 1 */ +#define IRRCV_NUM_DEVICES 256 +DECLARE_BITMAP(ir_core_dev_number, IRRCV_NUM_DEVICES); + /* Sizes are in bytes, 256 bytes allows for 32 entries on x64 */ #define IR_TAB_MIN_SIZE 256 #define IR_TAB_MAX_SIZE 8192 @@ -1203,10 +1207,9 @@ EXPORT_SYMBOL_GPL(rc_free_device); int rc_register_device(struct rc_dev *dev) { static bool raw_init = false; /* raw decoders loaded? */ - static atomic_t devno = ATOMIC_INIT(0); struct rc_map *rc_map; const char *path; - int rc; + int rc, devno; if (!dev || !dev->map_name) return -EINVAL; @@ -1234,7 +1237,15 @@ int rc_register_device(struct rc_dev *dev) */ mutex_lock(&dev->lock); - dev->devno = (unsigned long)(atomic_inc_return(&devno) - 1); + do { + devno = find_first_zero_bit(ir_core_dev_number, + IRRCV_NUM_DEVICES); + /* No free device slots */ + if (devno >= IRRCV_NUM_DEVICES) + return -ENOMEM; + } while (test_and_set_bit(devno, ir_core_dev_number)); + + dev->devno = devno; dev_set_name(&dev->dev, "rc%ld", dev->devno); dev_set_drvdata(&dev->dev, dev); rc = device_add(&dev->dev); @@ -1324,6 +1335,7 @@ out_dev: device_del(&dev->dev); out_unlock: mutex_unlock(&dev->lock); + clear_bit(dev->devno, ir_core_dev_number); return rc; } EXPORT_SYMBOL_GPL(rc_register_device); @@ -1335,6 +1347,8 @@ void rc_unregister_device(struct rc_dev *dev) del_timer_sync(&dev->timer_keyup); + clear_bit(dev->devno, ir_core_dev_number); + if (dev->driver_type == RC_DRIVER_IR_RAW) ir_raw_event_unregister(dev); -- 2.7.4