rv3028 provides clkout (enabled by default). Add clkout
to clock framework source and control from device tree for
variable frequency with enable and disable functionality.
Signed-off-by: Parthiban Nallathambi
---
Notes:
Notes:
Changlog in v2:
- Removed disabling the clock. clk core will disable it
when no consumer is detected
- Remove multiple write to CLKF
drivers/rtc/rtc-rv3028.c | 146 +++
1 file changed, 146 insertions(+)
diff --git a/drivers/rtc/rtc-rv3028.c b/drivers/rtc/rtc-rv3028.c
index 2b316661a578..6b7b3a69601a 100644
--- a/drivers/rtc/rtc-rv3028.c
+++ b/drivers/rtc/rtc-rv3028.c
@@ -8,6 +8,7 @@
*
*/
+#include
#include
#include
#include
@@ -52,6 +53,11 @@
#define RV3028_STATUS_CLKF BIT(6)
#define RV3028_STATUS_EEBUSY BIT(7)
+#define RV3028_CLKOUT_FD_MASK GENMASK(2, 0)
+#define RV3028_CLKOUT_PORIEBIT(3)
+#define RV3028_CLKOUT_CLKSYBIT(6)
+#define RV3028_CLKOUT_CLKOEBIT(7)
+
#define RV3028_CTRL1_EERD BIT(3)
#define RV3028_CTRL1_WADA BIT(5)
@@ -84,6 +90,9 @@ struct rv3028_data {
struct regmap *regmap;
struct rtc_device *rtc;
enum rv3028_type type;
+#ifdef CONFIG_COMMON_CLK
+ struct clk_hw clkout_hw;
+#endif
};
static u16 rv3028_trickle_resistors[] = {1000, 3000, 6000, 11000};
@@ -581,6 +590,140 @@ static int rv3028_eeprom_read(void *priv, unsigned int
offset, void *val,
return ret;
}
+#ifdef CONFIG_COMMON_CLK
+#define clkout_hw_to_rv3028(hw) container_of(hw, struct rv3028_data, clkout_hw)
+
+static int clkout_rates[] = {
+ 32768,
+ 8192,
+ 1024,
+ 64,
+ 32,
+ 1,
+};
+
+static unsigned long rv3028_clkout_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ int clkout, ret;
+ struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
+
+ ret = regmap_read(rv3028->regmap, RV3028_CLKOUT, &clkout);
+ if (ret < 0)
+ return 0;
+
+ clkout &= RV3028_CLKOUT_FD_MASK;
+ return clkout_rates[clkout];
+}
+
+static long rv3028_clkout_round_rate(struct clk_hw *hw, unsigned long rate,
+unsigned long *prate)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(clkout_rates); i++)
+ if (clkout_rates[i] <= rate)
+ return clkout_rates[i];
+
+ return 0;
+}
+
+static int rv3028_clkout_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ int i, ret;
+ struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
+
+ ret = regmap_write(rv3028->regmap, RV3028_CLKOUT, 0x0);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(clkout_rates); i++) {
+ if (clkout_rates[i] == rate) {
+ ret = regmap_update_bits(rv3028->regmap,
+RV3028_CLKOUT,
+RV3028_CLKOUT_FD_MASK, i);
+ if (ret < 0)
+ return ret;
+
+ return regmap_write(rv3028->regmap, RV3028_CLKOUT,
+ RV3028_CLKOUT_CLKSY | RV3028_CLKOUT_CLKOE);
+ }
+ }
+
+ return -EINVAL;
+}
+
+static int rv3028_clkout_prepare(struct clk_hw *hw)
+{
+ struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
+
+ return regmap_write(rv3028->regmap, RV3028_CLKOUT,
+ RV3028_CLKOUT_CLKSY | RV3028_CLKOUT_CLKOE);
+}
+
+static void rv3028_clkout_unprepare(struct clk_hw *hw)
+{
+ struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
+
+ regmap_write(rv3028->regmap, RV3028_CLKOUT, 0x0);
+ regmap_update_bits(rv3028->regmap, RV3028_STATUS,
+ RV3028_STATUS_CLKF, 0);
+}
+
+static int rv3028_clkout_is_prepared(struct clk_hw *hw)
+{
+ int clkout, ret;
+ struct rv3028_data *rv3028 = clkout_hw_to_rv3028(hw);
+
+ ret = regmap_read(rv3028->regmap, RV3028_CLKOUT, &clkout);
+ if (ret < 0)
+ return ret;
+
+ return !!(clkout & RV3028_CLKOUT_CLKOE);
+}
+
+static const struct clk_ops rv3028_clkout_ops = {
+ .prepare = rv3028_clkout_prepare,
+ .unprepare = rv3028_clkout_unprepare,
+ .is_prepared = rv3028_clkout_is_prepared,
+ .recalc_rate = rv3028_clkout_recalc_rate,
+ .round_rate = rv3028_clkout_round_rate,
+ .set_rate = rv3028_clkout_set_rate,
+};
+
+static int rv3028_clkout_register_clk(struct rv3028_data *rv3028,
+ struct i2c_client *client)
+{
+ int ret;
+ struct clk *clk;
+ struct clk_init_data init;
+ struct device_node *node = client->dev.of_node;
+
+ ret = regmap_update_bits(rv3028->regmap,
