ENGR00318773-8 ASoC: fsl_spdif: Add driver suspend and resume to support MEGA Fast

For i.MX6 SoloX, there is a mode of the SoC to shutdown all power source of
modules during system suspend and resume procedure. Thus, SPDIF needs to save
all the values of registers before the system suspend and restore them after
the system resume.

Acked-by: Wang Shengjiu <b02247@freescale.com>
Signed-off-by: Nicolin Chen <Guangyu.Chen@freescale.com>

1 files changed, 40 insertions, 0 deletions

diff --git a/sound/soc/fsl/fsl_spdif.c b/sound/soc/fsl/fsl_spdif.c
index b47c436e03a9..8df108966155 100644
--- a/sound/soc/fsl/fsl_spdif.c
+++ b/sound/soc/fsl/fsl_spdif.c
@@ -285,6 +285,8 @@ static int spdif_softreset(struct fsl_spdif_priv *spdif_priv)
         struct regmap *regmap = spdif_priv->regmap;
         u32 val, cycle = 1000;
 
+        regcache_cache_bypass(regmap, true);
+
         regmap_write(regmap, REG_SPDIF_SCR, SCR_SOFT_RESET);
 
         /*
@@ -295,6 +297,10 @@ static int spdif_softreset(struct fsl_spdif_priv *spdif_priv)
                 regmap_read(regmap, REG_SPDIF_SCR, &val);
         } while ((val & SCR_SOFT_RESET) && cycle--);
 
+        regcache_cache_bypass(regmap, false);
+        regcache_mark_dirty(regmap);
+        regcache_sync(regmap);
+
         if (cycle)
                 return 0;
         else
@@ -977,6 +983,17 @@ static bool fsl_spdif_readable_reg(struct device *dev, unsigned int reg)
         }
 }
 
+static bool fsl_spdif_volatile_reg(struct device *dev, unsigned int reg)
+{
+        switch (reg) {
+        case REG_SPDIF_SIS:
+                return true;
+        default:
+                return false;
+        }
+
+}
+
 static bool fsl_spdif_writeable_reg(struct device *dev, unsigned int reg)
 {
         switch (reg) {
@@ -1003,7 +1020,9 @@ static const struct regmap_config fsl_spdif_regmap_config = {
 
         .max_register = REG_SPDIF_STC,
         .readable_reg = fsl_spdif_readable_reg,
+        .volatile_reg = fsl_spdif_volatile_reg,
         .writeable_reg = fsl_spdif_writeable_reg,
+        .cache_type = REGCACHE_RBTREE,
 };
 
 static u32 fsl_spdif_txclk_caldiv(struct fsl_spdif_priv *spdif_priv,
@@ -1271,10 +1290,31 @@ static int fsl_spdif_runtime_suspend(struct device *dev)
 }
 #endif
 
+#ifdef CONFIG_PM_SLEEP
+static int fsl_spdif_suspend(struct device *dev)
+{
+        struct fsl_spdif_priv *spdif_priv = dev_get_drvdata(dev);
+
+        regcache_cache_only(spdif_priv->regmap, true);
+        regcache_mark_dirty(spdif_priv->regmap);
+
+        return 0;
+}
+
+static int fsl_spdif_resume(struct device *dev)
+{
+        struct fsl_spdif_priv *spdif_priv = dev_get_drvdata(dev);
+
+        regcache_cache_only(spdif_priv->regmap, false);
+        return regcache_sync(spdif_priv->regmap);
+}
+#endif /* CONFIG_PM_SLEEP */
+
 static const struct dev_pm_ops fsl_spdif_pm = {
         SET_RUNTIME_PM_OPS(fsl_spdif_runtime_suspend,
                         fsl_spdif_runtime_resume,
                         NULL)
+        SET_SYSTEM_SLEEP_PM_OPS(fsl_spdif_suspend, fsl_spdif_resume)
 };
 
 static const struct of_device_id fsl_spdif_dt_ids[] = {