ASoC: codecs: fsl_mqs: Add PM support

Save the values of registers at suspend and restore
it at resume.

We don't need to implement runtime PM support because
MQS is already enabled in startup() and disabled in
shutdown().

Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Reviewed-by: Shengjiu Wang <shengjiu.wang@nxp.com>

diff --git a/sound/soc/codecs/fsl_mqs.c b/sound/soc/codecs/fsl_mqs.c
index 3f7dc14..daf75fc 100644 (file)
--- a/sound/soc/codecs/fsl_mqs.c
+++ b/sound/soc/codecs/fsl_mqs.c
@@ -14,6 +14,7 @@
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
 #include <linux/of.h>
+#include <linux/pm.h>
 #include <linux/slab.h>
 #include <sound/soc.h>
 #include <sound/pcm.h>
@@ -36,7 +37,11 @@
 struct fsl_mqs {
        struct platform_device *pdev;
        struct regmap *gpr;
+       unsigned int reg_iomuxc_gpr2;
+
        struct regmap *regmap;
+       unsigned int reg_mqs_ctrl;
+
        struct clk *mclk;
        struct clk *ipg;
 
@@ -287,6 +292,40 @@ static int fsl_mqs_remove(struct platform_device *pdev)
        return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int fsl_mqs_resume(struct device *dev)
+{
+       struct fsl_mqs *mqs_priv = dev_get_drvdata(dev);
+
+       if (mqs_priv->use_gpr)
+               regmap_write(mqs_priv->gpr, IOMUXC_GPR2,
+                           mqs_priv->reg_iomuxc_gpr2);
+       else
+               regmap_write(mqs_priv->regmap, REG_MQS_CTRL,
+                            mqs_priv->reg_mqs_ctrl);
+
+       return 0;
+}
+
+static int fsl_mqs_suspend(struct device *dev)
+{
+       struct fsl_mqs *mqs_priv = dev_get_drvdata(dev);
+
+       if (mqs_priv->use_gpr)
+               regmap_read(mqs_priv->gpr, IOMUXC_GPR2,
+                           &mqs_priv->reg_iomuxc_gpr2);
+       else
+               regmap_read(mqs_priv->regmap, REG_MQS_CTRL,
+                           &mqs_priv->reg_mqs_ctrl);
+
+       return 0;
+}
+#endif
+
+static const struct dev_pm_ops fsl_mqs_pm_ops = {
+       SET_SYSTEM_SLEEP_PM_OPS(fsl_mqs_suspend, fsl_mqs_resume)
+};
+
 static const struct of_device_id fsl_mqs_dt_ids[] = {
        { .compatible = "fsl,imx8qm-mqs", },
        { .compatible = "fsl,imx6sx-mqs", },
@@ -301,6 +340,7 @@ static struct platform_driver fsl_mqs_driver = {
        .driver         = {
                .name   = "fsl-mqs",
                .of_match_table = fsl_mqs_dt_ids,
+               .pm = &fsl_mqs_pm_ops,
        },
 };