ASoC: da7219: Add common clock usage for providing DAI clks

There is a need to use DA7219 as DAI clock master for other codecs
within a system, which means that the DAI clocks are required to
remain, regardless of whether the codec is actually running
playback/capture. To be able to expose control of the DAI clocking
the common clock framework has been employed.

The current implementation adds a simple clock gate for enabling
and disabling the DAI clocks, with no rate control supported
(this is still handled through standard hw_params() functions as
before). If DT is enabled then the clock is added to the OF
providers list, otherwise a clkdev lookup is used.

Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/Documentation/devicetree/bindings/sound/da7219.txt b/Documentation/devicetree/bindings/sound/da7219.txt
index 5b54d2d..c3df92d 100644 (file)
--- a/Documentation/devicetree/bindings/sound/da7219.txt
+++ b/Documentation/devicetree/bindings/sound/da7219.txt
@@ -25,6 +25,9 @@ Optional properties:
   interrupt is to be used to wake system, otherwise "irq" should be used.
 - wakeup-source: Flag to indicate this device can wake system (suspend/resume).
 
+- #clock-cells :  Should be set to '<0>', only one clock source provided;
+- clock-output-names : Name given for DAI clocks output;
+
 - clocks : phandle and clock specifier for codec MCLK.
 - clock-names : Clock name string for 'clocks' attribute, should be "mclk".
 
@@ -83,6 +86,9 @@ Example:
                VDDMIC-supply = <&reg_audio>;
                VDDIO-supply = <&reg_audio>;
 
+               #clock-cells = <0>;
+               clock-output-names = "dai-clks";
+
                clocks = <&clks 201>;
                clock-names = "mclk";
 

diff --git a/include/sound/da7219.h b/include/sound/da7219.h
index 409ef13..1bfcb16 100644 (file)
--- a/include/sound/da7219.h
+++ b/include/sound/da7219.h
@@ -36,6 +36,8 @@ struct da7219_aad_pdata;
 struct da7219_pdata {
        bool wakeup_source;
 
+       const char *dai_clks_name;
+
        /* Mic */
        enum da7219_micbias_voltage micbias_lvl;
        enum da7219_mic_amp_in_sel mic_amp_in_sel;

diff --git a/sound/soc/codecs/da7219.c b/sound/soc/codecs/da7219.c
index 5e043d0..4412159 100644 (file)
--- a/sound/soc/codecs/da7219.c
+++ b/sound/soc/codecs/da7219.c
@@ -13,6 +13,8 @@
 
 #include <linux/acpi.h>
 #include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
 #include <linux/i2c.h>
 #include <linux/of_device.h>
 #include <linux/property.h>
@@ -772,16 +774,27 @@ static int da7219_dai_event(struct snd_soc_dapm_widget *w,
        struct snd_soc_component *component = snd_soc_dapm_to_component(w->dapm);
        struct da7219_priv *da7219 = snd_soc_component_get_drvdata(component);
        u8 pll_ctrl, pll_status;
-       int i = 0;
+       int i = 0, ret;
        bool srm_lock = false;
 
        switch (event) {
        case SND_SOC_DAPM_PRE_PMU:
-               if (da7219->master)
+               if (da7219->master) {
                        /* Enable DAI clks for master mode */
-                       snd_soc_component_update_bits(component, DA7219_DAI_CLK_MODE,
-                                           DA7219_DAI_CLK_EN_MASK,
-                                           DA7219_DAI_CLK_EN_MASK);
+                       if (da7219->dai_clks) {
+                               ret = clk_prepare_enable(da7219->dai_clks);
+                               if (ret) {
+                                       dev_err(component->dev,
+                                               "Failed to enable dai_clks\n");
+                                       return ret;
+                               }
+                       } else {
+                               snd_soc_component_update_bits(component,
+                                                             DA7219_DAI_CLK_MODE,
+                                                             DA7219_DAI_CLK_EN_MASK,
+                                                             DA7219_DAI_CLK_EN_MASK);
+                       }
+               }
 
                /* PC synchronised to DAI */
                snd_soc_component_update_bits(component, DA7219_PC_COUNT,
@@ -814,9 +827,16 @@ static int da7219_dai_event(struct snd_soc_dapm_widget *w,
                                    DA7219_PC_FREERUN_MASK);
 
                /* Disable DAI clks if in master mode */
-               if (da7219->master)
-                       snd_soc_component_update_bits(component, DA7219_DAI_CLK_MODE,
-                                           DA7219_DAI_CLK_EN_MASK, 0);
+               if (da7219->master) {
+                       if (da7219->dai_clks)
+                               clk_disable_unprepare(da7219->dai_clks);
+                       else
+                               snd_soc_component_update_bits(component,
+                                                             DA7219_DAI_CLK_MODE,
+                                                             DA7219_DAI_CLK_EN_MASK,
+                                                             0);
+               }
+
                return 0;
        default:
                return -EINVAL;
@@ -1598,6 +1618,12 @@ static struct da7219_pdata *da7219_fw_to_pdata(struct snd_soc_component *compone
 
        pdata->wakeup_source = device_property_read_bool(dev, "wakeup-source");
 
+       pdata->dai_clks_name = "da7219-dai-clks";
+       if (device_property_read_string(dev, "clock-output-names",
+                                       &pdata->dai_clks_name))
+               dev_warn(dev, "Using default clk name: %s\n",
+                        pdata->dai_clks_name);
+
        if (device_property_read_u32(dev, "dlg,micbias-lvl", &of_val32) >= 0)
                pdata->micbias_lvl = da7219_fw_micbias_lvl(dev, of_val32);
        else
@@ -1712,6 +1738,88 @@ static int da7219_handle_supplies(struct snd_soc_component *component)
        return 0;
 }
 
+#ifdef CONFIG_COMMON_CLK
+static int da7219_dai_clks_prepare(struct clk_hw *hw)
+{
+       struct da7219_priv *da7219 =
+               container_of(hw, struct da7219_priv, dai_clks_hw);
+       struct snd_soc_component *component = da7219->aad->component;
+
+       snd_soc_component_update_bits(component, DA7219_DAI_CLK_MODE,
+                                     DA7219_DAI_CLK_EN_MASK,
+                                     DA7219_DAI_CLK_EN_MASK);
+
+       return 0;
+}
+
+static void da7219_dai_clks_unprepare(struct clk_hw *hw)
+{
+       struct da7219_priv *da7219 =
+               container_of(hw, struct da7219_priv, dai_clks_hw);
+       struct snd_soc_component *component = da7219->aad->component;
+
+       snd_soc_component_update_bits(component, DA7219_DAI_CLK_MODE,
+                                     DA7219_DAI_CLK_EN_MASK, 0);
+}
+
+static int da7219_dai_clks_is_prepared(struct clk_hw *hw)
+{
+       struct da7219_priv *da7219 =
+               container_of(hw, struct da7219_priv, dai_clks_hw);
+       struct snd_soc_component *component = da7219->aad->component;
+       u8 clk_reg;
+
+       clk_reg = snd_soc_component_read32(component, DA7219_DAI_CLK_MODE);
+
+       return !!(clk_reg & DA7219_DAI_CLK_EN_MASK);
+}
+
+const struct clk_ops da7219_dai_clks_ops = {
+       .prepare = da7219_dai_clks_prepare,
+       .unprepare = da7219_dai_clks_unprepare,
+       .is_prepared = da7219_dai_clks_is_prepared,
+};
+
+static void da7219_register_dai_clks(struct snd_soc_component *component)
+{
+       struct device *dev = component->dev;
+       struct da7219_priv *da7219 = snd_soc_component_get_drvdata(component);
+       struct da7219_pdata *pdata = da7219->pdata;
+       struct clk_init_data init = {};
+       struct clk *dai_clks;
+       struct clk_lookup *dai_clks_lookup;
+
+       init.parent_names = NULL;
+       init.num_parents = 0;
+       init.name = pdata->dai_clks_name;
+       init.ops = &da7219_dai_clks_ops;
+       da7219->dai_clks_hw.init = &init;
+
+       dai_clks = devm_clk_register(dev, &da7219->dai_clks_hw);
+       if (IS_ERR(dai_clks)) {
+               dev_warn(dev, "Failed to register DAI clocks: %ld\n",
+                        PTR_ERR(dai_clks));
+               return;
+       }
+       da7219->dai_clks = dai_clks;
+
+       /* If we're using DT, then register as provider accordingly */
+       if (dev->of_node) {
+               devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get,
+                                           &da7219->dai_clks_hw);
+       } else {
+               dai_clks_lookup = clkdev_create(dai_clks, pdata->dai_clks_name,
+                                               "%s", dev_name(dev));
+               if (!dai_clks_lookup)
+                       dev_warn(dev, "Failed to create DAI clkdev");
+               else
+                       da7219->dai_clks_lookup = dai_clks_lookup;
+       }
+}
+#else
+static inline void da7219_register_dai_clks(struct snd_soc_component *component) {}
+#endif /* CONFIG_COMMON_CLK */
+
 static void da7219_handle_pdata(struct snd_soc_component *component)
 {
        struct da7219_priv *da7219 = snd_soc_component_get_drvdata(component);
@@ -1722,6 +1830,8 @@ static void da7219_handle_pdata(struct snd_soc_component *component)
 
                da7219->wakeup_source = pdata->wakeup_source;
 
+               da7219_register_dai_clks(component);
+
                /* Mic Bias voltages */
                switch (pdata->micbias_lvl) {
                case DA7219_MICBIAS_1_6V:
@@ -1856,6 +1966,9 @@ static void da7219_remove(struct snd_soc_component *component)
 
        da7219_aad_exit(component);
 
+       if (da7219->dai_clks_lookup)
+               clkdev_drop(da7219->dai_clks_lookup);
+
        /* Supplies */
        regulator_bulk_disable(DA7219_NUM_SUPPLIES, da7219->supplies);
 }

diff --git a/sound/soc/codecs/da7219.h b/sound/soc/codecs/da7219.h
index 1acb34c..1b00023 100644 (file)
--- a/sound/soc/codecs/da7219.h
+++ b/sound/soc/codecs/da7219.h
@@ -14,6 +14,9 @@
 #ifndef __DA7219_H
 #define __DA7219_H
 
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
 #include <sound/da7219.h>
@@ -813,6 +816,12 @@ struct da7219_priv {
        struct mutex ctrl_lock;
        struct mutex pll_lock;
 
+#ifdef CONFIG_COMMON_CLK
+       struct clk_hw dai_clks_hw;
+#endif
+       struct clk_lookup *dai_clks_lookup;
+       struct clk *dai_clks;
+
        struct clk *mclk;
        unsigned int mclk_rate;
        int clk_src;