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authorJisheng Zhang <jszhang@marvell.com>2015-11-25 17:41:25 +0800
committerThierry Reding <thierry.reding@gmail.com>2016-09-06 10:48:52 +0200
commitbbf0722c1c663b08f612bd8c58af27f45aa84862 (patch)
tree4430cb48660f32d478a56248537d39b7e15074ec /drivers/pwm/pwm-berlin.c
parent45c0ce847a99ca053d432ea98e4ff55d88357d7e (diff)
pwm: berlin: Add suspend/resume support
This patch adds suspend-to-RAM support to the Berlin PWM driver. Signed-off-by: Jisheng Zhang <jszhang@marvell.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm/pwm-berlin.c')
-rw-r--r--drivers/pwm/pwm-berlin.c84
1 files changed, 84 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-berlin.c b/drivers/pwm/pwm-berlin.c
index 65108129d505..01339c152ab0 100644
--- a/drivers/pwm/pwm-berlin.c
+++ b/drivers/pwm/pwm-berlin.c
@@ -16,6 +16,7 @@
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
+#include <linux/slab.h>
#define BERLIN_PWM_EN 0x0
#define BERLIN_PWM_ENABLE BIT(0)
@@ -27,6 +28,13 @@
#define BERLIN_PWM_TCNT 0xc
#define BERLIN_PWM_MAX_TCNT 65535
+struct berlin_pwm_channel {
+ u32 enable;
+ u32 ctrl;
+ u32 duty;
+ u32 tcnt;
+};
+
struct berlin_pwm_chip {
struct pwm_chip chip;
struct clk *clk;
@@ -55,6 +63,25 @@ static inline void berlin_pwm_writel(struct berlin_pwm_chip *chip,
writel_relaxed(value, chip->base + channel * 0x10 + offset);
}
+static int berlin_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct berlin_pwm_channel *channel;
+
+ channel = kzalloc(sizeof(*channel), GFP_KERNEL);
+ if (!channel)
+ return -ENOMEM;
+
+ return pwm_set_chip_data(pwm, channel);
+}
+
+static void berlin_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct berlin_pwm_channel *channel = pwm_get_chip_data(pwm);
+
+ pwm_set_chip_data(pwm, NULL);
+ kfree(channel);
+}
+
static int berlin_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm_dev,
int duty_ns, int period_ns)
{
@@ -137,6 +164,8 @@ static void berlin_pwm_disable(struct pwm_chip *chip,
}
static const struct pwm_ops berlin_pwm_ops = {
+ .request = berlin_pwm_request,
+ .free = berlin_pwm_free,
.config = berlin_pwm_config,
.set_polarity = berlin_pwm_set_polarity,
.enable = berlin_pwm_enable,
@@ -204,12 +233,67 @@ static int berlin_pwm_remove(struct platform_device *pdev)
return ret;
}
+#ifdef CONFIG_PM_SLEEP
+static int berlin_pwm_suspend(struct device *dev)
+{
+ struct berlin_pwm_chip *pwm = dev_get_drvdata(dev);
+ unsigned int i;
+
+ for (i = 0; i < pwm->chip.npwm; i++) {
+ struct berlin_pwm_channel *channel;
+
+ channel = pwm_get_chip_data(&pwm->chip.pwms[i]);
+ if (!channel)
+ continue;
+
+ channel->enable = berlin_pwm_readl(pwm, i, BERLIN_PWM_ENABLE);
+ channel->ctrl = berlin_pwm_readl(pwm, i, BERLIN_PWM_CONTROL);
+ channel->duty = berlin_pwm_readl(pwm, i, BERLIN_PWM_DUTY);
+ channel->tcnt = berlin_pwm_readl(pwm, i, BERLIN_PWM_TCNT);
+ }
+
+ clk_disable_unprepare(pwm->clk);
+
+ return 0;
+}
+
+static int berlin_pwm_resume(struct device *dev)
+{
+ struct berlin_pwm_chip *pwm = dev_get_drvdata(dev);
+ unsigned int i;
+ int ret;
+
+ ret = clk_prepare_enable(pwm->clk);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < pwm->chip.npwm; i++) {
+ struct berlin_pwm_channel *channel;
+
+ channel = pwm_get_chip_data(&pwm->chip.pwms[i]);
+ if (!channel)
+ continue;
+
+ berlin_pwm_writel(pwm, i, channel->ctrl, BERLIN_PWM_CONTROL);
+ berlin_pwm_writel(pwm, i, channel->duty, BERLIN_PWM_DUTY);
+ berlin_pwm_writel(pwm, i, channel->tcnt, BERLIN_PWM_TCNT);
+ berlin_pwm_writel(pwm, i, channel->enable, BERLIN_PWM_ENABLE);
+ }
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(berlin_pwm_pm_ops, berlin_pwm_suspend,
+ berlin_pwm_resume);
+
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);