mfd: Enable twl4030 32kHz oscillator low-power mode

Allows TWL's 32kHz oscillator to go in low-power mode when
main battery voltage is running low.

Signed-off-by: Ilkka Koskinen <ilkka.koskinen@nokia.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

diff --git a/drivers/mfd/twl4030-core.c b/drivers/mfd/twl4030-core.c
index e3abbf6..90a38e4 100644 (file)
--- a/drivers/mfd/twl4030-core.c
+++ b/drivers/mfd/twl4030-core.c
@@ -183,6 +183,7 @@
 #define HFCLK_FREQ_26_MHZ              (2 << 0)
 #define HFCLK_FREQ_38p4_MHZ            (3 << 0)
 #define HIGH_PERF_SQ                   (1 << 3)
+#define CK32K_LOWPWR_EN                        (1 << 7)
 
 
 /* chip-specific feature flags, for i2c_device_id.driver_data */
@@ -695,7 +696,8 @@ static inline int __init unprotect_pm_master(void)
        return e;
 }
 
-static void clocks_init(struct device *dev)
+static void clocks_init(struct device *dev,
+                       struct twl4030_clock_init_data *clock)
 {
        int e = 0;
        struct clk *osc;
@@ -742,6 +744,9 @@ static void clocks_init(struct device *dev)
        }
 
        ctrl |= HIGH_PERF_SQ;
+       if (clock && clock->ck32k_lowpwr_enable)
+               ctrl |= CK32K_LOWPWR_EN;
+
        e |= unprotect_pm_master();
        /* effect->MADC+USB ck en */
        e |= twl4030_i2c_write_u8(TWL4030_MODULE_PM_MASTER, ctrl, R_CFG_BOOT);
@@ -820,7 +825,7 @@ twl4030_probe(struct i2c_client *client, const struct i2c_device_id *id)
        inuse = true;
 
        /* setup clock framework */
-       clocks_init(&client->dev);
+       clocks_init(&client->dev, pdata->clock);
 
        /* load power event scripts */
        if (twl_has_power() && pdata->power)

diff --git a/include/linux/i2c/twl4030.h b/include/linux/i2c/twl4030.h
index 8a4a58f..0c84cfa 100644 (file)
--- a/include/linux/i2c/twl4030.h
+++ b/include/linux/i2c/twl4030.h
@@ -313,6 +313,10 @@ int twl4030_i2c_read(u8 mod_no, u8 *value, u8 reg, unsigned num_bytes);
 
 /*----------------------------------------------------------------------*/
 
+struct twl4030_clock_init_data {
+       bool ck32k_lowpwr_enable;
+};
+
 struct twl4030_bci_platform_data {
        int *battery_tmp_tbl;
        unsigned int tblsize;
@@ -425,6 +429,7 @@ struct twl4030_codec_data {
 
 struct twl4030_platform_data {
        unsigned                                irq_base, irq_end;
+       struct twl4030_clock_init_data          *clock;
        struct twl4030_bci_platform_data        *bci;
        struct twl4030_gpio_platform_data       *gpio;
        struct twl4030_madc_platform_data       *madc;