[PATCH] pwm: berlin: Add PM support

[Jisheng Zhang <jszhang@marvell.com>]

This patch adds S2R support for berlin pwm driver.

Signed-off-by: Jisheng Zhang <jszhang@marvell.com>
---
 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