On 27 October 2016 at 17:34, Marcel Hasler <mahasler@xxxxxxxxx> wrote:
> 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, there's no point trying to setup the unavailable AC97 codec.
>
> Signed-off-by: Marcel Hasler <mahasler@xxxxxxxxx>
> ---
> drivers/media/usb/stk1160/stk1160-ac97.c | 15 +++++++++++++++
> drivers/media/usb/stk1160/stk1160-core.c | 3 +--
> drivers/media/usb/stk1160/stk1160-reg.h | 3 +++
> 3 files changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/media/usb/stk1160/stk1160-ac97.c b/drivers/media/usb/stk1160/stk1160-ac97.c
> index d3665ce..6dbc39f 100644
> --- a/drivers/media/usb/stk1160/stk1160-ac97.c
> +++ b/drivers/media/usb/stk1160/stk1160-ac97.c
> @@ -90,8 +90,23 @@ void stk1160_ac97_dump_regs(struct stk1160 *dev)
> }
> #endif
>
> +int stk1160_has_ac97(struct stk1160 *dev)
> +{
> + u8 value;
> +
> + stk1160_read_reg(dev, STK1160_POSVA, &value);
> +
> + /* Bit 2 high means internal ADC */
> + return !(value & 0x04);
How about define a macro such as:
diff --git a/drivers/media/usb/stk1160/stk1160-reg.h
b/drivers/media/usb/stk1160/stk1160-reg.h
index a4ab586fcee1..4922249d7d34 100644
--- a/drivers/media/usb/stk1160/stk1160-reg.h
+++ b/drivers/media/usb/stk1160/stk1160-reg.h
@@ -28,6 +28,7 @@
/* Power-on Strapping Data */
#define STK1160_POSVA 0x010
+#define STK1160_POSVA_ACSYNC BIT(2)
Also, the spec mentions another POSVA bit relevant
to audio ACDOUT. Should we check that too?
> +}
> +
> void stk1160_ac97_setup(struct stk1160 *dev)
> {
> + 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);
> diff --git a/drivers/media/usb/stk1160/stk1160-core.c b/drivers/media/usb/stk1160/stk1160-core.c
> index f3c9b8a..c86eb61 100644
> --- a/drivers/media/usb/stk1160/stk1160-core.c
> +++ b/drivers/media/usb/stk1160/stk1160-core.c
> @@ -20,8 +20,7 @@
> *
> * TODO:
> *
> - * 1. (Try to) detect if we must register ac97 mixer
> - * 2. Support stream at lower speed: lower frame rate or lower frame size.
> + * 1. Support stream at lower speed: lower frame rate or lower frame size.
> *
> */
>
> diff --git a/drivers/media/usb/stk1160/stk1160-reg.h b/drivers/media/usb/stk1160/stk1160-reg.h
> index 81ff3a1..a4ab586 100644
> --- a/drivers/media/usb/stk1160/stk1160-reg.h
> +++ b/drivers/media/usb/stk1160/stk1160-reg.h
> @@ -26,6 +26,9 @@
> /* Remote Wakup Control */
> #define STK1160_RMCTL 0x00c
>
> +/* Power-on Strapping Data */
> +#define STK1160_POSVA 0x010
> +
> /*
> * Decoder Control Register:
> * This byte controls capture start/stop
> --
> 2.10.1
>
--
Ezequiel García, VanguardiaSur
www.vanguardiasur.com.ar
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