[2/3] clk: si5351: Add DT property to enable PLL reset

Commit Message

Sergej Sawazki Aug. 12, 2017, 2:23 p.m. UTC

Add optional output clock DT property to enable PLL reset when a clock
output is enabled or the clock rate is changed.

Cc: Sebastian Hesselbarth <[e-mail]>
Cc: Rabeeh Khoury <[e-mail]>
Signed-off-by: Sergej Sawazki <[e-mail]>
---
 Documentation/devicetree/bindings/clock/silabs,si5351.txt |  1 +
 drivers/clk/clk-si5351.c                                  | 11 ++++++++++-
 include/linux/platform_data/si5351.h                      |  2 ++
 3 files changed, 13 insertions(+), 1 deletion(-)

Patch

diff --git a/Documentation/devicetree/bindings/clock/silabs,si5351.txt b/Documentation/devicetree/bindings/clock/silabs,si5351.txt
index 28b2830..157ee02 100644
--- a/Documentation/devicetree/bindings/clock/silabs,si5351.txt
+++ b/Documentation/devicetree/bindings/clock/silabs,si5351.txt
@@ -45,6 +45,7 @@  Optional child node properties:
 - silabs,multisynth-source: source pll A(0) or B(1) of corresponding multisynth
   divider.
 - silabs,pll-master: boolean, multisynth can change pll frequency.
+- silabs,pll-reset: boolean, clock output can reset its pll.
 - silabs,disable-state : clock output disable state, shall be
   0 = clock output is driven LOW when disabled
   1 = clock output is driven HIGH when disabled
diff --git a/drivers/clk/clk-si5351.c b/drivers/clk/clk-si5351.c
index 46bbc95..aa8d8d9 100644
--- a/drivers/clk/clk-si5351.c
+++ b/drivers/clk/clk-si5351.c
@@ -900,7 +900,13 @@  static int _si5351_clkout_set_disable_state(
 
 void _si5351_clkout_reset_pll(struct si5351_driver_data *drvdata, int num)
 {
-	u8 val = si5351_reg_read(drvdata, SI5351_CLK0_CTRL + num);
+	struct si5351_platform_data *pdata = drvdata->client->dev.platform_data;
+	u8 val;
+
+	if (!pdata->clkout[num].pll_reset)
+		return;  /* Resetting PLL disabled */
+
+	val = si5351_reg_read(drvdata, SI5351_CLK0_CTRL + num);
 
 	switch (val & SI5351_CLK_INPUT_MASK) {
 	case SI5351_CLK_INPUT_XTAL:
@@ -1321,6 +1327,9 @@  static int si5351_dt_parse(struct i2c_client *client,
 
 		pdata->clkout[num].pll_master =
 			of_property_read_bool(child, "silabs,pll-master");
+
+		pdata->clkout[num].pll_reset =
+			of_property_read_bool(child, "silabs,pll-reset");
 	}
 	client->dev.platform_data = pdata;
 
diff --git a/include/linux/platform_data/si5351.h b/include/linux/platform_data/si5351.h
index 533d980..da346f22 100644
--- a/include/linux/platform_data/si5351.h
+++ b/include/linux/platform_data/si5351.h
@@ -85,6 +85,7 @@  enum si5351_disable_state {
  * @multisynth_src: multisynth source clock
  * @clkout_src: clkout source clock
  * @pll_master: if true, clkout can also change pll rate
+ * @pll_reset: if true, clkout can reset its pll
  * @drive: output drive strength
  * @rate: initial clkout rate, or default if 0
  */
@@ -94,6 +95,7 @@  struct si5351_clkout_config {
 	enum si5351_drive_strength drive;
 	enum si5351_disable_state disable_state;
 	bool pll_master;
+	bool pll_reset;
 	unsigned long rate;
 };