diff options
| author | Ed Blake <ed.blake@sondrel.com> | 2017-10-02 11:51:47 +0200 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@gmail.com> | 2017-11-15 10:38:04 +0100 |
| commit | a18afce522e8c469132e740f840f2b95b2008987 (patch) | |
| tree | 7bab12668eb638bc68806675f9a5fca78c90cb42 /drivers/pwm | |
| parent | Linux 4.14-rc1 (diff) | |
| download | linux-a18afce522e8c469132e740f840f2b95b2008987.tar.xz linux-a18afce522e8c469132e740f840f2b95b2008987.zip | |
pwm: img: Add suspend / resume handling
The power may be disabled during suspend, so implement suspend and
resume callbacks to save and restore register state.
Signed-off-by: Ed Blake <ed.blake@sondrel.com>
[thierry.reding@gmail.com: guard using PM_SLEEP instead of PM]
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/pwm-img.c | 66 |
1 files changed, 65 insertions, 1 deletions
diff --git a/drivers/pwm/pwm-img.c b/drivers/pwm/pwm-img.c index 2fb30deee345..b54daf2917bf 100644 --- a/drivers/pwm/pwm-img.c +++ b/drivers/pwm/pwm-img.c @@ -52,6 +52,8 @@ */ #define MIN_TMBASE_STEPS 16 +#define IMG_PWM_NPWM 4 + struct img_pwm_soc_data { u32 max_timebase; }; @@ -66,6 +68,8 @@ struct img_pwm_chip { int max_period_ns; int min_period_ns; const struct img_pwm_soc_data *data; + u32 suspend_ctrl_cfg; + u32 suspend_ch_cfg[IMG_PWM_NPWM]; }; static inline struct img_pwm_chip *to_img_pwm_chip(struct pwm_chip *chip) @@ -255,7 +259,7 @@ static int img_pwm_probe(struct platform_device *pdev) pwm->chip.dev = &pdev->dev; pwm->chip.ops = &img_pwm_ops; pwm->chip.base = -1; - pwm->chip.npwm = 4; + pwm->chip.npwm = IMG_PWM_NPWM; ret = pwmchip_add(&pwm->chip); if (ret < 0) { @@ -291,9 +295,69 @@ static int img_pwm_remove(struct platform_device *pdev) return pwmchip_remove(&pwm_chip->chip); } +#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; + + for (i = 0; i < pwm_chip->chip.npwm; i++) + pwm_chip->suspend_ch_cfg[i] = img_pwm_readl(pwm_chip, + PWM_CH_CFG(i)); + + 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); + + 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); + 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"); + 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), + pwm_chip->suspend_ch_cfg[i]); + + img_pwm_writel(pwm_chip, PWM_CTRL_CFG, pwm_chip->suspend_ctrl_cfg); + + for (i = 0; i < pwm_chip->chip.npwm; i++) + if (pwm_chip->suspend_ctrl_cfg & BIT(i)) + regmap_update_bits(pwm_chip->periph_regs, + PERIP_PWM_PDM_CONTROL, + PERIP_PWM_PDM_CONTROL_CH_MASK << + PERIP_PWM_PDM_CONTROL_CH_SHIFT(i), + 0); + + return 0; +} +#endif /* CONFIG_PM */ + +SIMPLE_DEV_PM_OPS(img_pwm_pm_ops, img_pwm_suspend, img_pwm_resume); + static struct platform_driver img_pwm_driver = { .driver = { .name = "img-pwm", + .pm = &img_pwm_pm_ops, .of_match_table = img_pwm_of_match, }, .probe = img_pwm_probe, |