From e690ae526216b913c61977193eb7e4b803511e75 Mon Sep 17 00:00:00 2001 From: Ed Blake Date: Mon, 2 Oct 2017 10:51:48 +0100 Subject: pwm: img: Add runtime PM Add runtime PM to disable the clocks when the h/w is not in use. Signed-off-by: Ed Blake Signed-off-by: Thierry Reding --- drivers/pwm/pwm-img.c | 132 ++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 95 insertions(+), 37 deletions(-) (limited to 'drivers/pwm') diff --git a/drivers/pwm/pwm-img.c b/drivers/pwm/pwm-img.c index b54daf2917bf..815f5333bb8f 100644 --- a/drivers/pwm/pwm-img.c +++ b/drivers/pwm/pwm-img.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -39,6 +40,8 @@ #define PERIP_PWM_PDM_CONTROL_CH_MASK 0x1 #define PERIP_PWM_PDM_CONTROL_CH_SHIFT(ch) ((ch) * 4) +#define IMG_PWM_PM_TIMEOUT 1000 /* ms */ + /* * PWM period is specified with a timebase register, * in number of step periods. The PWM duty cycle is also @@ -96,6 +99,7 @@ static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, unsigned long mul, output_clk_hz, input_clk_hz; struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip); unsigned int max_timebase = pwm_chip->data->max_timebase; + int ret; if (period_ns < pwm_chip->min_period_ns || period_ns > pwm_chip->max_period_ns) { @@ -127,6 +131,10 @@ static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, duty = DIV_ROUND_UP(timebase * duty_ns, period_ns); + ret = pm_runtime_get_sync(chip->dev); + if (ret < 0) + return ret; + val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG); val &= ~(PWM_CTRL_CFG_DIV_MASK << PWM_CTRL_CFG_DIV_SHIFT(pwm->hwpwm)); val |= (div & PWM_CTRL_CFG_DIV_MASK) << @@ -137,6 +145,9 @@ static int img_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, (timebase << PWM_CH_CFG_TMBASE_SHIFT); img_pwm_writel(pwm_chip, PWM_CH_CFG(pwm->hwpwm), val); + pm_runtime_mark_last_busy(chip->dev); + pm_runtime_put_autosuspend(chip->dev); + return 0; } @@ -144,6 +155,11 @@ static int img_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { u32 val; struct img_pwm_chip *pwm_chip = to_img_pwm_chip(chip); + int ret; + + ret = pm_runtime_get_sync(chip->dev); + if (ret < 0) + return ret; val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG); val |= BIT(pwm->hwpwm); @@ -164,6 +180,9 @@ static void img_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG); val &= ~BIT(pwm->hwpwm); img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val); + + pm_runtime_mark_last_busy(chip->dev); + pm_runtime_put_autosuspend(chip->dev); } static const struct pwm_ops img_pwm_ops = { @@ -186,6 +205,37 @@ static const struct of_device_id img_pwm_of_match[] = { }; MODULE_DEVICE_TABLE(of, img_pwm_of_match); +static int img_pwm_runtime_suspend(struct device *dev) +{ + struct img_pwm_chip *pwm_chip = dev_get_drvdata(dev); + + clk_disable_unprepare(pwm_chip->pwm_clk); + clk_disable_unprepare(pwm_chip->sys_clk); + + return 0; +} + +static int img_pwm_runtime_resume(struct device *dev) +{ + struct img_pwm_chip *pwm_chip = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(pwm_chip->sys_clk); + if (ret < 0) { + dev_err(dev, "could not prepare or enable sys clock\n"); + return ret; + } + + ret = clk_prepare_enable(pwm_chip->pwm_clk); + if (ret < 0) { + dev_err(dev, "could not prepare or enable pwm clock\n"); + clk_disable_unprepare(pwm_chip->sys_clk); + return ret; + } + + return 0; +} + static int img_pwm_probe(struct platform_device *pdev) { int ret; @@ -228,23 +278,20 @@ static int img_pwm_probe(struct platform_device *pdev) return PTR_ERR(pwm->pwm_clk); } - ret = clk_prepare_enable(pwm->sys_clk); - if (ret < 0) { - dev_err(&pdev->dev, "could not prepare or enable sys clock\n"); - return ret; - } - - ret = clk_prepare_enable(pwm->pwm_clk); - if (ret < 0) { - dev_err(&pdev->dev, "could not prepare or enable pwm clock\n"); - goto disable_sysclk; + pm_runtime_set_autosuspend_delay(&pdev->dev, IMG_PWM_PM_TIMEOUT); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_enable(&pdev->dev); + if (!pm_runtime_enabled(&pdev->dev)) { + ret = img_pwm_runtime_resume(&pdev->dev); + if (ret) + goto err_pm_disable; } clk_rate = clk_get_rate(pwm->pwm_clk); if (!clk_rate) { dev_err(&pdev->dev, "pwm clock has no frequency\n"); ret = -EINVAL; - goto disable_pwmclk; + goto err_suspend; } /* The maximum input clock divider is 512 */ @@ -264,16 +311,18 @@ static int img_pwm_probe(struct platform_device *pdev) ret = pwmchip_add(&pwm->chip); if (ret < 0) { dev_err(&pdev->dev, "pwmchip_add failed: %d\n", ret); - goto disable_pwmclk; + goto err_suspend; } platform_set_drvdata(pdev, pwm); return 0; -disable_pwmclk: - clk_disable_unprepare(pwm->pwm_clk); -disable_sysclk: - clk_disable_unprepare(pwm->sys_clk); +err_suspend: + if (!pm_runtime_enabled(&pdev->dev)) + img_pwm_runtime_suspend(&pdev->dev); +err_pm_disable: + pm_runtime_disable(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); return ret; } @@ -282,6 +331,11 @@ static int img_pwm_remove(struct platform_device *pdev) struct img_pwm_chip *pwm_chip = platform_get_drvdata(pdev); u32 val; unsigned int i; + int ret; + + ret = pm_runtime_get_sync(&pdev->dev); + if (ret < 0) + return ret; for (i = 0; i < pwm_chip->chip.npwm; i++) { val = img_pwm_readl(pwm_chip, PWM_CTRL_CFG); @@ -289,8 +343,10 @@ static int img_pwm_remove(struct platform_device *pdev) img_pwm_writel(pwm_chip, PWM_CTRL_CFG, val); } - clk_disable_unprepare(pwm_chip->pwm_clk); - clk_disable_unprepare(pwm_chip->sys_clk); + pm_runtime_put(&pdev->dev); + pm_runtime_disable(&pdev->dev); + if (!pm_runtime_status_suspended(&pdev->dev)) + img_pwm_runtime_suspend(&pdev->dev); return pwmchip_remove(&pwm_chip->chip); } @@ -298,9 +354,14 @@ static int img_pwm_remove(struct platform_device *pdev) #ifdef CONFIG_PM_SLEEP static int img_pwm_suspend(struct device *dev) { - struct platform_device *pdev = to_platform_device(dev); - struct img_pwm_chip *pwm_chip = platform_get_drvdata(pdev); - int i; + struct img_pwm_chip *pwm_chip = dev_get_drvdata(dev); + int i, ret; + + if (pm_runtime_status_suspended(dev)) { + ret = img_pwm_runtime_resume(dev); + if (ret) + return ret; + } for (i = 0; i < pwm_chip->chip.npwm; i++) pwm_chip->suspend_ch_cfg[i] = img_pwm_readl(pwm_chip, @@ -308,31 +369,20 @@ static int img_pwm_suspend(struct device *dev) pwm_chip->suspend_ctrl_cfg = img_pwm_readl(pwm_chip, PWM_CTRL_CFG); - clk_disable_unprepare(pwm_chip->pwm_clk); - clk_disable_unprepare(pwm_chip->sys_clk); + img_pwm_runtime_suspend(dev); return 0; } static int img_pwm_resume(struct device *dev) { - struct platform_device *pdev = to_platform_device(dev); - struct img_pwm_chip *pwm_chip = platform_get_drvdata(pdev); + struct img_pwm_chip *pwm_chip = dev_get_drvdata(dev); int ret; int i; - ret = clk_prepare_enable(pwm_chip->sys_clk); - if (ret < 0) { - dev_err(&pdev->dev, "could not prepare or enable sys clock\n"); + ret = img_pwm_runtime_resume(dev); + if (ret) return ret; - } - - ret = clk_prepare_enable(pwm_chip->pwm_clk); - if (ret < 0) { - dev_err(&pdev->dev, "could not prepare or enable pwm clock\n"); - clk_disable_unprepare(pwm_chip->sys_clk); - return ret; - } for (i = 0; i < pwm_chip->chip.npwm; i++) img_pwm_writel(pwm_chip, PWM_CH_CFG(i), @@ -348,11 +398,19 @@ static int img_pwm_resume(struct device *dev) PERIP_PWM_PDM_CONTROL_CH_SHIFT(i), 0); + if (pm_runtime_status_suspended(dev)) + img_pwm_runtime_suspend(dev); + return 0; } #endif /* CONFIG_PM */ -SIMPLE_DEV_PM_OPS(img_pwm_pm_ops, img_pwm_suspend, img_pwm_resume); +static const struct dev_pm_ops img_pwm_pm_ops = { + SET_RUNTIME_PM_OPS(img_pwm_runtime_suspend, + img_pwm_runtime_resume, + NULL) + SET_SYSTEM_SLEEP_PM_OPS(img_pwm_suspend, img_pwm_resume) +}; static struct platform_driver img_pwm_driver = { .driver = { -- cgit