[media] radio-si470x: Don't unnecesarily read registers on G_TUNER

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Reading registers from the pcear USB dongles with the si470x causes a
loud pop (and an alsa buffer overrun). Since most radio apps periodically
call G_TUNER to update mono/stereo, signal and afc status this leads
to the music . pop . music . pop . music -> not good.

On the internet there is an howto for flashing the pcear with a newer
firmware from the silabs reference boardto fix this, but:
1) This howto relies on a special version of the driver which allows
   firmware flashing
2) We should try to avoid the answer to a bug report being upgrade your
   firmware, if at all possible
3) Windows does not suffer from the pop sounds

After a quick look at the driver I found at that the register reads are
not necessary at all, as the device gives us the necessary status through
usb interrupt packets, and the driver already uses these!

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

...

This commit is contained in:

Hans de Goede 2012-06-14 09:43:11 -03:00 • committed by Mauro Carvalho Chehab

parent 8e2ce73e93

commit 86ef3f78b8

3 changed files with 16 additions and 7 deletions

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10

drivers/media/radio/si470x/radio-si470x-common.c

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12

drivers/media/radio/si470x/radio-si470x-usb.c

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1

drivers/media/radio/si470x/radio-si470x.h

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