[PATCH v2 1/2] [media] rc-core: fix protocol_change regression in ir_raw_event_register

From: Tomas Melin
Date: Tue Oct 21 2014 - 14:31:01 EST


IR reciever using nuvoton-cir and lirc required additional configuration
steps after upgrade from kernel 3.16 to 3.17-rcX.
Bisected regression to commit da6e162d6a4607362f8478c715c797d84d449f8b
("[media] rc-core: simplify sysfs code").

The regression comes from adding empty function change_protocol in
ir-raw.c. It changes behaviour so that only the protocol enabled by driver's
map_name will be active after registration. This breaks user space behaviour,
lirc does not get key press signals anymore.

Changed back to original behaviour by removing empty function
change_protocol in ir-raw.c. Instead only calling change_protocol for
drivers that actually have the function set up.

Signed-off-by: Tomas Melin <tomas.melin@xxxxxx>
---
drivers/media/rc/rc-ir-raw.c | 7 -------
drivers/media/rc/rc-main.c | 19 ++++++++-----------
2 files changed, 8 insertions(+), 18 deletions(-)

diff --git a/drivers/media/rc/rc-ir-raw.c b/drivers/media/rc/rc-ir-raw.c
index e8fff2a..a118539 100644
--- a/drivers/media/rc/rc-ir-raw.c
+++ b/drivers/media/rc/rc-ir-raw.c
@@ -240,12 +240,6 @@ ir_raw_get_allowed_protocols(void)
return protocols;
}

-static int change_protocol(struct rc_dev *dev, u64 *rc_type)
-{
- /* the caller will update dev->enabled_protocols */
- return 0;
-}
-
/*
* Used to (un)register raw event clients
*/
@@ -263,7 +257,6 @@ int ir_raw_event_register(struct rc_dev *dev)

dev->raw->dev = dev;
dev->enabled_protocols = ~0;
- dev->change_protocol = change_protocol;
rc = kfifo_alloc(&dev->raw->kfifo,
sizeof(struct ir_raw_event) * MAX_IR_EVENT_SIZE,
GFP_KERNEL);
diff --git a/drivers/media/rc/rc-main.c b/drivers/media/rc/rc-main.c
index a7991c7..633c682 100644
--- a/drivers/media/rc/rc-main.c
+++ b/drivers/media/rc/rc-main.c
@@ -1001,11 +1001,6 @@ static ssize_t store_protocols(struct device *device,
set_filter = dev->s_wakeup_filter;
}

- if (!change_protocol) {
- IR_dprintk(1, "Protocol switching not supported\n");
- return -EINVAL;
- }
-
mutex_lock(&dev->lock);

old_protocols = *current_protocols;
@@ -1013,12 +1008,14 @@ static ssize_t store_protocols(struct device *device,
rc = parse_protocol_change(&new_protocols, buf);
if (rc < 0)
goto out;
-
- rc = change_protocol(dev, &new_protocols);
- if (rc < 0) {
- IR_dprintk(1, "Error setting protocols to 0x%llx\n",
- (long long)new_protocols);
- goto out;
+ /* Only if protocol change set up in driver */
+ if (change_protocol) {
+ rc = change_protocol(dev, &new_protocols);
+ if (rc < 0) {
+ IR_dprintk(1, "Error setting protocols to 0x%llx\n",
+ (long long)new_protocols);
+ goto out;
+ }
}

if (new_protocols == old_protocols) {
--
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/