mfd: twl6040: Optional clk32k clock handling
authorPeter Ujfalusi <peter.ujfalusi@ti.com>
Thu, 3 Apr 2014 10:54:41 +0000 (13:54 +0300)
committerLee Jones <lee.jones@linaro.org>
Tue, 3 Jun 2014 07:11:20 +0000 (08:11 +0100)
In certain boards the source for the clk32k clock can be gated. In these
boards the clk32k clock can be provided to the driver and it is going to be
enabled/disabled when it is needed.
If the clk32k clock is not provided the driver will assume that it is always
running.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Documentation/devicetree/bindings/mfd/twl6040.txt
drivers/mfd/twl6040.c
include/linux/mfd/twl6040.h

index 0f5dd709d752490815fab1a978b8c2ff1c1f383b..a41157b5d930d2c0ed1dfaee5fd9c0aa9d392d1e 100644 (file)
@@ -19,6 +19,8 @@ Required properties:
 
 Optional properties, nodes:
 - enable-active-high: To power on the twl6040 during boot.
+- clocks: phandle to the clk32k clock provider
+- clock-names: Must be "clk32k"
 
 Vibra functionality
 Required properties:
index cb37bb8f8e41e76877a098f18941c06ee4d08864..574774d7f826ab3d6ca047e22fcf7c6f239177ec 100644 (file)
@@ -291,6 +291,8 @@ int twl6040_power(struct twl6040 *twl6040, int on)
                if (twl6040->power_count++)
                        goto out;
 
+               clk_prepare_enable(twl6040->clk32k);
+
                /* Allow writes to the chip */
                regcache_cache_only(twl6040->regmap, false);
 
@@ -346,6 +348,8 @@ int twl6040_power(struct twl6040 *twl6040, int on)
 
                twl6040->sysclk = 0;
                twl6040->mclk = 0;
+
+               clk_disable_unprepare(twl6040->clk32k);
        }
 
 out:
@@ -644,6 +648,12 @@ static int twl6040_probe(struct i2c_client *client,
 
        i2c_set_clientdata(client, twl6040);
 
+       twl6040->clk32k = devm_clk_get(&client->dev, "clk32k");
+       if (IS_ERR(twl6040->clk32k)) {
+               dev_info(&client->dev, "clk32k is not handled\n");
+               twl6040->clk32k = NULL;
+       }
+
        twl6040->supplies[0].supply = "vio";
        twl6040->supplies[1].supply = "v2v1";
        ret = devm_regulator_bulk_get(&client->dev, TWL6040_NUM_SUPPLIES,
index a69d16b30c1862e610a05a4d76fe97e38c1dcf91..8f9fc3d26e6d1e8582938dc20004c1988aad4147 100644 (file)
@@ -28,6 +28,7 @@
 #include <linux/interrupt.h>
 #include <linux/mfd/core.h>
 #include <linux/regulator/consumer.h>
+#include <linux/clk.h>
 
 #define TWL6040_REG_ASICID             0x01
 #define TWL6040_REG_ASICREV            0x02
@@ -223,6 +224,7 @@ struct twl6040 {
        struct regmap *regmap;
        struct regmap_irq_chip_data *irq_data;
        struct regulator_bulk_data supplies[2]; /* supplies for vio, v2v1 */
+       struct clk *clk32k;
        struct mutex mutex;
        struct mutex irq_mutex;
        struct mfd_cell cells[TWL6040_CELLS];