This patch adds suspend/resume function support for Renesas the 16-Bit Timer
Pulse Unit (TPU) driver. This has been tested on the Salvator-XS board
with R-Car M3-N and H3 at renesas-drivers-2019-05-21-v5.2-rc1 tag.
I expect this to work on other SoCs.
Test procedure:
- Enable TPU and pin control in DTS.
- Make sure switches { SW29-[1-2] are switched off or
SW31-[1-4] are switched off(only for Salvator-xs) }.
- Exercise userspace PWM control for pwm[2,3]
of /sys/class/pwm/pwmchip1/ .
- Inspect PWM signals on the input side of { CN29-[58,60]
or SW31-[1,2] (only for Salvator-xs) }
before and after suspend/resume using an oscilloscope.
Signed-off-by: Cao Van Dong <[email protected]>
Tested-by: Cao Van Dong <[email protected]>
---
drivers/pwm/pwm-renesas-tpu.c | 49 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 49 insertions(+)
diff --git a/drivers/pwm/pwm-renesas-tpu.c b/drivers/pwm/pwm-renesas-tpu.c
index 4a855a2..97b026e 100644
--- a/drivers/pwm/pwm-renesas-tpu.c
+++ b/drivers/pwm/pwm-renesas-tpu.c
@@ -366,6 +366,54 @@ static void tpu_pwm_disable(struct pwm_chip *chip, struct
pwm_device *_pwm)
tpu_pwm_timer_stop(pwm);
}
+#ifdef CONFIG_PM_SLEEP
+static struct pwm_device *tpu_pwm_dev_to_pwm_dev(struct device *dev)
+{
+ struct tpu_device *tpu = dev_get_drvdata(dev);
+ struct pwm_chip *chip = &tpu->chip;
+
+ if((pwm_get_chip_data(&chip->pwms[0])) != NULL)
+ return &chip->pwms[0];
+ if((pwm_get_chip_data(&chip->pwms[1])) != NULL)
+ return &chip->pwms[1];
+ if((pwm_get_chip_data(&chip->pwms[2])) != NULL)
+ return &chip->pwms[2];
+ if((pwm_get_chip_data(&chip->pwms[3])) != NULL)
+ return &chip->pwms[3];
+
+ return NULL;
+}
+
+static int tpu_pwm_suspend(struct device *dev)
+{
+ struct pwm_device *pwm = tpu_pwm_dev_to_pwm_dev(dev);
+
+ if (!test_bit(PWMF_REQUESTED, &pwm->flags))
+ return 0;
+
+ pm_runtime_put(dev);
+
+ return 0;
+}
+
+static int tpu_pwm_resume(struct device *dev)
+{
+ struct pwm_device *pwm = tpu_pwm_dev_to_pwm_dev(dev);
+
+ if ((!test_bit(PWMF_REQUESTED, &pwm->flags)) || pwm == NULL)
+ return 0;
+
+ pm_runtime_get_sync(dev);
+
+ /* Restart timer */
+ tpu_pwm_disable(pwm->chip,pwm);
+ tpu_pwm_enable(pwm->chip,pwm);
+
+ return 0;
+}
+#endif /* CONFIG_PM_SLEEP */
+static SIMPLE_DEV_PM_OPS(tpu_pwm_pm_ops, tpu_pwm_suspend, tpu_pwm_resume);
+
static const struct pwm_ops tpu_pwm_ops = {
.request = tpu_pwm_request,
.free = tpu_pwm_free,
@@ -459,6 +507,7 @@ static struct platform_driver tpu_driver = {
.remove = tpu_remove,
.driver = {
.name = "renesas-tpu-pwm",
+ .pm = &tpu_pwm_pm_ops,
.of_match_table = of_match_ptr(tpu_of_table),
}
};
--
2.7.4
