diff options
| author | Marcel Hasler <mahasler@gmail.com> | 2016-12-15 20:13:34 -0200 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2017-02-03 11:26:32 -0200 |
| commit | 1dc7df4d3d787639c9eeb8fc3841dd8d003de82a (patch) | |
| tree | e05a0d41e1a6a82ad3d20f38230b466827cf48f5 /drivers/media/usb/stk1160/stk1160-ac97.c | |
| parent | e36e6b5f26c14fd588d5c7e78527d3707f8ac836 (diff) | |
[media] stk1160: Check whether to use AC97 codec
Some STK1160-based devices use the chip's internal 8-bit ADC. This is
configured through a strap pin. The value of this and other pins can be
read through the POSVA register. If the internal ADC is used, or if
audio is disabled altogether, there's no point trying to setup the AC97
codec.
Signed-off-by: Marcel Hasler <mahasler@gmail.com>
Acked-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers/media/usb/stk1160/stk1160-ac97.c')
| -rw-r--r-- | drivers/media/usb/stk1160/stk1160-ac97.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/media/usb/stk1160/stk1160-ac97.c b/drivers/media/usb/stk1160/stk1160-ac97.c index 502fc8ee9a97..5e9b76edd81c 100644 --- a/drivers/media/usb/stk1160/stk1160-ac97.c +++ b/drivers/media/usb/stk1160/stk1160-ac97.c @@ -91,8 +91,34 @@ void stk1160_ac97_dump_regs(struct stk1160 *dev) } #endif +int stk1160_has_audio(struct stk1160 *dev) +{ + u8 value; + + stk1160_read_reg(dev, STK1160_POSV_L, &value); + return !(value & STK1160_POSV_L_ACDOUT); +} + +int stk1160_has_ac97(struct stk1160 *dev) +{ + u8 value; + + stk1160_read_reg(dev, STK1160_POSV_L, &value); + return !(value & STK1160_POSV_L_ACSYNC); +} + void stk1160_ac97_setup(struct stk1160 *dev) { + if (!stk1160_has_audio(dev)) { + stk1160_info("Device doesn't support audio, skipping AC97 setup."); + return; + } + + if (!stk1160_has_ac97(dev)) { + stk1160_info("Device uses internal 8-bit ADC, skipping AC97 setup."); + return; + } + /* Two-step reset AC97 interface and hardware codec */ stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x94); stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x8c); |