From bbf0722c1c663b08f612bd8c58af27f45aa84862 Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Wed, 25 Nov 2015 17:41:25 +0800 Subject: pwm: berlin: Add suspend/resume support This patch adds suspend-to-RAM support to the Berlin PWM driver. Signed-off-by: Jisheng Zhang Signed-off-by: Thierry Reding --- drivers/pwm/pwm-berlin.c | 84 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 84 insertions(+) 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 #include #include +#include #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); -- cgit v1.2.3