clk: pwm: Make use of non-sleeping PWMs

For some PWMs applying a configuration doesn't sleep. For these enabling
and disabling can be done in the clk callbacks .enable() and .disable()
instead of .prepare() and .unprepare().

Do that to possibly reduce the time the PWM is enabled and so save some
energy.

Signed-off-by: Uwe Kleine-König <[email protected]>
Link: https://lore.kernel.org/r/d2f748101194409fb410711380ea52ed33260644.1746006578.git.ukleinek@baylibre.com
Signed-off-by: Stephen Boyd <[email protected]>

Author: ukleinek

drivers/clk/clk-pwm.c

@@ -23,6 +23,23 @@ static inline struct clk_pwm *to_clk_pwm(struct clk_hw *hw)
 	return container_of(hw, struct clk_pwm, hw);
 }
 
+static int clk_pwm_enable(struct clk_hw *hw)
+{
+	struct clk_pwm *clk_pwm = to_clk_pwm(hw);
+
+	return pwm_apply_atomic(clk_pwm->pwm, &clk_pwm->state);
+}
+
+static void clk_pwm_disable(struct clk_hw *hw)
+{
+	struct clk_pwm *clk_pwm = to_clk_pwm(hw);
+	struct pwm_state state = clk_pwm->state;
+
+	state.enabled = false;
+
+	pwm_apply_atomic(clk_pwm->pwm, &state);
+}
+
 static int clk_pwm_prepare(struct clk_hw *hw)
 {
 	struct clk_pwm *clk_pwm = to_clk_pwm(hw);
@@ -61,6 +78,13 @@ static int clk_pwm_get_duty_cycle(struct clk_hw *hw, struct clk_duty *duty)
 	return 0;
 }
 
+static const struct clk_ops clk_pwm_ops_atomic = {
+	.enable = clk_pwm_enable,
+	.disable = clk_pwm_disable,
+	.recalc_rate = clk_pwm_recalc_rate,
+	.get_duty_cycle = clk_pwm_get_duty_cycle,
+};
+
 static const struct clk_ops clk_pwm_ops = {
 	.prepare = clk_pwm_prepare,
 	.unprepare = clk_pwm_unprepare,
@@ -115,7 +139,11 @@ static int clk_pwm_probe(struct platform_device *pdev)
 	of_property_read_string(node, "clock-output-names", &clk_name);
 
 	init.name = clk_name;
-	init.ops = &clk_pwm_ops;
+	if (pwm_might_sleep(pwm))
+		init.ops = &clk_pwm_ops;
+	else
+		init.ops = &clk_pwm_ops_atomic;
+
 	init.flags = 0;
 	init.num_parents = 0;