mfd: twl-core: API to set the regcache bypass for a given regmap in twl

If the regcache is enabled on the regmap module drivers might need to access
to HW register(s) in certain cases in cache bypass mode.
As an example of this is the audio block's ANAMICL register. In normal
operation the content can be cached but during initialization one bit from
the register need to be monitored. With the twl_set_regcache_bypass() the
client driver can switch regcache bypass on and off when it is needed so
we can utilize the regcache for more registers.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

diff --git a/drivers/mfd/twl-core.c b/drivers/mfd/twl-core.c
index c91cb4367b9bc2b005d878d66ce29df74b41261c..f0abca79ff348a0f4d9b78a520e43f653e0e933f 100644 (file)
--- a/drivers/mfd/twl-core.c
+++ b/drivers/mfd/twl-core.c
@@ -383,6 +383,27 @@ int twl_i2c_read(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes)
 }
 EXPORT_SYMBOL(twl_i2c_read);
 
+/**
+ * twl_regcache_bypass - Configure the regcache bypass for the regmap associated
+ *                      with the module
+ * @mod_no: module number
+ * @enable: Regcache bypass state
+ *
+ * Returns 0 else failure.
+ */
+int twl_set_regcache_bypass(u8 mod_no, bool enable)
+{
+       struct regmap *regmap = twl_get_regmap(mod_no);
+
+       if (!regmap)
+               return -EPERM;
+
+       regcache_cache_bypass(regmap, enable);
+
+       return 0;
+}
+EXPORT_SYMBOL(twl_set_regcache_bypass);
+
 /*----------------------------------------------------------------------*/
 
 /**

diff --git a/include/linux/i2c/twl.h b/include/linux/i2c/twl.h
index 673a3ce67f311df6567aa780dfdbf3d7adbe0cf9..a09da09103391cdbad66b372e0abe3ec36e3ceac 100644 (file)
--- a/include/linux/i2c/twl.h
+++ b/include/linux/i2c/twl.h
@@ -175,6 +175,9 @@ static inline int twl_class_is_ ##class(void)       \
 TWL_CLASS_IS(4030, TWL4030_CLASS_ID)
 TWL_CLASS_IS(6030, TWL6030_CLASS_ID)
 
+/* Set the regcache bypass for the regmap associated with the nodule */
+int twl_set_regcache_bypass(u8 mod_no, bool enable);
+
 /*
  * Read and write several 8-bit registers at once.
  */