[PATCH] pwm: berlin: Add PM support

From: Jisheng Zhang
Date: Tue Nov 24 2015 - 00:47:18 EST


This patch adds S2R support for berlin pwm driver.

Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
---
drivers/pwm/pwm-berlin.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 56 insertions(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-berlin.c b/drivers/pwm/pwm-berlin.c
index 6510812..2afdb40 100644
--- a/drivers/pwm/pwm-berlin.c
+++ b/drivers/pwm/pwm-berlin.c
@@ -27,10 +27,20 @@
#define BERLIN_PWM_TCNT 0xc
#define BERLIN_PWM_MAX_TCNT 65535

+#define NUM_PWM_CHANNEL 4 /* berlin PWM channels */
+
+struct berlin_pwm_context {
+ u32 enable;
+ u32 ctrl;
+ u32 duty;
+ u32 tcnt;
+};
+
struct berlin_pwm_chip {
struct pwm_chip chip;
struct clk *clk;
void __iomem *base;
+ struct berlin_pwm_context ctx[NUM_PWM_CHANNEL];
};

static inline struct berlin_pwm_chip *to_berlin_pwm_chip(struct pwm_chip *chip)
@@ -176,7 +186,7 @@ static int berlin_pwm_probe(struct platform_device *pdev)
pwm->chip.dev = &pdev->dev;
pwm->chip.ops = &berlin_pwm_ops;
pwm->chip.base = -1;
- pwm->chip.npwm = 4;
+ pwm->chip.npwm = NUM_PWM_CHANNEL;
pwm->chip.can_sleep = true;
pwm->chip.of_xlate = of_pwm_xlate_with_flags;
pwm->chip.of_pwm_n_cells = 3;
@@ -204,12 +214,57 @@ static int berlin_pwm_remove(struct platform_device *pdev)
return ret;
}

+#ifdef CONFIG_PM_SLEEP
+static int berlin_pwm_suspend(struct device *dev)
+{
+ int i;
+ struct berlin_pwm_chip *pwm = dev_get_drvdata(dev);
+
+ for (i = 0; i < pwm->chip.npwm; i++) {
+ struct berlin_pwm_context *ctx = &pwm->ctx[i];
+
+ ctx->enable = berlin_pwm_readl(pwm, i, BERLIN_PWM_ENABLE);
+ ctx->ctrl = berlin_pwm_readl(pwm, i, BERLIN_PWM_CONTROL);
+ ctx->duty = berlin_pwm_readl(pwm, i, BERLIN_PWM_DUTY);
+ ctx->tcnt = berlin_pwm_readl(pwm, i, BERLIN_PWM_TCNT);
+ }
+ clk_disable_unprepare(pwm->clk);
+
+ return 0;
+}
+
+static int berlin_pwm_resume(struct device *dev)
+{
+ int i;
+ struct berlin_pwm_chip *pwm = dev_get_drvdata(dev);
+
+ clk_prepare_enable(pwm->clk);
+ for (i = 0; i < pwm->chip.npwm; i++) {
+ struct berlin_pwm_context *ctx = &pwm->ctx[i];
+
+ berlin_pwm_writel(pwm, i, ctx->ctrl, BERLIN_PWM_CONTROL);
+ berlin_pwm_writel(pwm, i, ctx->duty, BERLIN_PWM_DUTY);
+ berlin_pwm_writel(pwm, i, ctx->tcnt, BERLIN_PWM_TCNT);
+ berlin_pwm_writel(pwm, i, ctx->enable, BERLIN_PWM_ENABLE);
+ }
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(berlin_pwm_pm_ops, berlin_pwm_suspend,
+ berlin_pwm_resume);
+#define BERLIN_PWM_PM_OPS (&berlin_pwm_pm_ops)
+#else
+#define BERLIN_PWM_PM_OPS NULL
+#endif
+
static struct platform_driver berlin_pwm_driver = {
.probe = berlin_pwm_probe,
.remove = berlin_pwm_remove,
.driver = {
.name = "berlin-pwm",
.of_match_table = berlin_pwm_match,
+ .pm = BERLIN_PWM_PM_OPS,
},
};
module_platform_driver(berlin_pwm_driver);
--
2.6.2

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