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| author | Mauro Carvalho Chehab <mchehab@infradead.org> | 2008-08-05 10:03:17 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2008-10-12 09:36:47 -0200 |
| commit | 622ecb300345d308c8b4a983ac112b1985d7d156 (patch) | |
| tree | 2dd9156f8a5bb27826a939034d1ffa7cac671211 /include/media | |
| parent | d56dc61265d2527a63ab5b0f03199a43cd89ca36 (diff) | |
| download | op-kernel-dev-622ecb300345d308c8b4a983ac112b1985d7d156.zip op-kernel-dev-622ecb300345d308c8b4a983ac112b1985d7d156.tar.gz | |
V4L/DVB (8625): saa7134: Add NEC prococol IR decoding capability
This patch adds the capability of decoding NEC protocol, received via GPIO18 line.
This GPIO port can trigger saa7134 IRQ.
A future improvement would be to make it a little more generic to work also
with GPIO16 line.
A pure IRQ code didn't work, since some delays were introduced on the tests we
did.
A possible approach would be to use polling at a rate of 2.5 ms or less. If a
new code were taken, a code similar to nec_task() could be used. However, this
would add an extra overhead to kernel, and will consume more power.
Due to that, we took an hybrid approach: an IRQ upper half to trigger when a
new key is received and a bottom half to convert pulse-distance into a keycode.
The bottom half is polling based, to improve performance. During the bottom
half proccess, GPIO18 IRQ line is disabled, preventing IRQ reentrancy and
improving performance a little bit.
Thanks to Sistema Fenix (http://www.sistemafenix.com.br/) for sponsoring this
development.
Signed-off-by: Gilberto <gilberto@sistemafenix.com.br>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Diffstat (limited to 'include/media')
| -rw-r--r-- | include/media/ir-common.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/media/ir-common.h b/include/media/ir-common.h index b8e8aa9..f5566d4 100644 --- a/include/media/ir-common.h +++ b/include/media/ir-common.h @@ -25,6 +25,7 @@ #include <linux/input.h> #include <linux/workqueue.h> +#include <linux/interrupt.h> #define IR_TYPE_RC5 1 #define IR_TYPE_PD 2 /* Pulse distance encoded IR */ @@ -85,6 +86,10 @@ struct card_ir { u32 code; /* raw code under construction */ struct timeval base_time; /* time of last seen code */ int active; /* building raw code */ + + /* NEC decoding */ + u32 nec_gpio; + struct tasklet_struct tlet; }; void ir_input_init(struct input_dev *dev, struct ir_input_state *ir, |
