[PATCH 1/4] ASoC: sun4i-codec: Add support for PA gpio pin
Chen-Yu Tsai
wens at csie.org
Fri Nov 20 08:42:41 PST 2015
On Sat, Nov 21, 2015 at 12:30 AM, Maxime Ripard
<maxime.ripard at free-electrons.com> wrote:
> On Fri, Nov 20, 2015 at 02:47:10PM +0100, Hans de Goede wrote:
>> Add support for PA gpio pin for controlling an external amplifier as used
>> on some Allwinner boards.
>>
>> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
>> ---
>> .../devicetree/bindings/sound/sun4i-codec.txt | 3 +++
>> sound/soc/sunxi/sun4i-codec.c | 25 ++++++++++++++--------
>> 2 files changed, 19 insertions(+), 9 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/sound/sun4i-codec.txt b/Documentation/devicetree/bindings/sound/sun4i-codec.txt
>> index c92966b..974babe 100644
>> --- a/Documentation/devicetree/bindings/sound/sun4i-codec.txt
>> +++ b/Documentation/devicetree/bindings/sound/sun4i-codec.txt
>> @@ -14,6 +14,9 @@ Required properties:
>> - "apb": the parent APB clock for this controller
>> - "codec": the parent module clock
>>
>> +Optional properties:
>> +- pa-gpios: gpio to enable external amplifier
>
> This is a custom property, it should be prefixed by the vendor name.
>
>> +
>> Example:
>> codec: codec at 01c22c00 {
>> #sound-dai-cells = <0>;
>> diff --git a/sound/soc/sunxi/sun4i-codec.c b/sound/soc/sunxi/sun4i-codec.c
>> index bcbf4da..2aca9cd 100644
>> --- a/sound/soc/sunxi/sun4i-codec.c
>> +++ b/sound/soc/sunxi/sun4i-codec.c
>> @@ -27,6 +27,7 @@
>> #include <linux/of_address.h>
>> #include <linux/clk.h>
>> #include <linux/regmap.h>
>> +#include <linux/gpio/consumer.h>
>>
>> #include <sound/core.h>
>> #include <sound/pcm.h>
>> @@ -101,16 +102,15 @@ struct sun4i_codec {
>> struct regmap *regmap;
>> struct clk *clk_apb;
>> struct clk *clk_module;
>> + struct gpio_desc *gpio_pa;
>>
>> struct snd_dmaengine_dai_dma_data playback_dma_data;
>> };
>>
>> static void sun4i_codec_start_playback(struct sun4i_codec *scodec)
>> {
>> - /*
>> - * FIXME: according to the BSP, we might need to drive a PA
>> - * GPIO high here on some boards
>> - */
>> + if (scodec->gpio_pa)
>> + gpiod_set_value_cansleep(scodec->gpio_pa, 1);
>>
>> /* Flush TX FIFO */
>> regmap_update_bits(scodec->regmap, SUN4I_CODEC_DAC_FIFOC,
>> @@ -125,15 +125,13 @@ static void sun4i_codec_start_playback(struct sun4i_codec *scodec)
>>
>> static void sun4i_codec_stop_playback(struct sun4i_codec *scodec)
>> {
>> - /*
>> - * FIXME: according to the BSP, we might need to drive a PA
>> - * GPIO low here on some boards
>> - */
>> -
>> /* Disable DAC DRQ */
>> regmap_update_bits(scodec->regmap, SUN4I_CODEC_DAC_FIFOC,
>> BIT(SUN4I_CODEC_DAC_FIFOC_DAC_DRQ_EN),
>> 0);
>> +
>> + if (scodec->gpio_pa)
>> + gpiod_set_value_cansleep(scodec->gpio_pa, 0);
>
> You should rather plug that into DAPM, using a speaker widget, and a
> custom event function that will enable or disable the amplifier only
> when this audio path is going to be used.
Isn't an "amplifier" widget better suited?
ChenYu
> You can see such an example here:
> http://lxr.free-electrons.com/source/sound/soc/jz4740/qi_lb60.c#L29
>
> That will require to modify a bit sun4i_codec_create_card as well in
> order to add the new widgets (and routes) when the DT property is
> found.
>
> Thanks!
> Maxime
>
> --
> Maxime Ripard, Free Electrons
> Embedded Linux, Kernel and Android engineering
> http://free-electrons.com
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