ASoC: make clock direction configurable in asoc-simple

Some CPU drivers (e. g. davinci-mcasp) may require the system clock to
be configured as OUT, while there's no good way currently to set
SND_SOC_CLK_OUT in simple-soc driver if the clock is fixed-rate.

This patch makes asoc_simple_card_init_dai() initialize clock to
SND_SOCK_CLK_OUT if explicitly stated in the relevant dts file. This
change is transparent and doesn't change the default behavior.

Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/Documentation/devicetree/bindings/sound/simple-card.txt b/Documentation/devicetree/bindings/sound/simple-card.txt
index c7a9393..166f229 100644 (file)
--- a/Documentation/devicetree/bindings/sound/simple-card.txt
+++ b/Documentation/devicetree/bindings/sound/simple-card.txt
@@ -86,6 +86,9 @@ Optional CPU/CODEC subnodes properties:
                                          in dai startup() and disabled with
                                          clk_disable_unprepare() in dai
                                          shutdown().
+- system-clock-direction-out           : specifies clock direction as 'out' on
+                                         initialization. It is useful for some aCPUs with
+                                         fixed clocks.
 
 Example 1 - single DAI link:
 

diff --git a/include/sound/simple_card_utils.h b/include/sound/simple_card_utils.h
index 42c6a6a..7e25afc 100644 (file)
--- a/include/sound/simple_card_utils.h
+++ b/include/sound/simple_card_utils.h
@@ -15,6 +15,7 @@
 struct asoc_simple_dai {
        const char *name;
        unsigned int sysclk;
+       int clk_direction;
        int slots;
        int slot_width;
        unsigned int tx_slot_mask;

diff --git a/sound/soc/generic/simple-card-utils.c b/sound/soc/generic/simple-card-utils.c
index 26d64fa..af44c8c 100644 (file)
--- a/sound/soc/generic/simple-card-utils.c
+++ b/sound/soc/generic/simple-card-utils.c
@@ -196,7 +196,11 @@ int asoc_simple_card_parse_clk(struct device *dev,
                        simple_dai->sysclk = clk_get_rate(clk);
        }
 
-       dev_dbg(dev, "%s : sysclk = %d\n", name, simple_dai->sysclk);
+       if (of_property_read_bool(node, "system-clock-direction-out"))
+               simple_dai->clk_direction = SND_SOC_CLOCK_OUT;
+
+       dev_dbg(dev, "%s : sysclk = %d, direction %d\n", name,
+               simple_dai->sysclk, simple_dai->clk_direction);
 
        return 0;
 }
@@ -310,7 +314,8 @@ int asoc_simple_card_init_dai(struct snd_soc_dai *dai,
        int ret;
 
        if (simple_dai->sysclk) {
-               ret = snd_soc_dai_set_sysclk(dai, 0, simple_dai->sysclk, 0);
+               ret = snd_soc_dai_set_sysclk(dai, 0, simple_dai->sysclk,
+                                            simple_dai->clk_direction);
                if (ret && ret != -ENOTSUPP) {
                        dev_err(dai->dev, "simple-card: set_sysclk error\n");
                        return ret;