Messages in this thread Patch in this message | | | From | Jisheng Zhang <> | Subject | [PATCH v2] pwm: berlin: Add PM support | Date | Wed, 25 Nov 2015 17:41:25 +0800 |
| |
This patch adds S2R support for berlin pwm driver.
Signed-off-by: Jisheng Zhang <jszhang@marvell.com> --- Since v1: - implement .request and .free hooks, allocate/free the channel in berlin_pwm_request/berlin_pwm_free. Then use pwm_get_chip_data in suspend/resume implementation. - s/int/unsigned int - check return value of clk_prepare_enable - remoev BERLIN_PWM_PM_OPS macro drivers/pwm/pwm-berlin.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 89 insertions(+), 1 deletion(-)
diff --git a/drivers/pwm/pwm-berlin.c b/drivers/pwm/pwm-berlin.c index 6510812..a66b9ff 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 +28,15 @@ #define BERLIN_PWM_TCNT 0xc #define BERLIN_PWM_MAX_TCNT 65535 +#define NUM_PWM_CHANNEL 4 /* berlin PWM channels */ + +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 +65,28 @@ 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_dev) +{ + struct berlin_pwm_channel *chan; + + if (pwm_dev->hwpwm >= NUM_PWM_CHANNEL) + return -EINVAL; + + chan = kzalloc(sizeof(*chan), GFP_KERNEL); + if (!chan) + return -ENOMEM; + + return pwm_set_chip_data(pwm_dev, chan); +} + +static void berlin_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm_dev) +{ + struct berlin_pwm_channel *chan = pwm_get_chip_data(pwm_dev); + + kfree(chan); + pwm_set_chip_data(pwm_dev, NULL); +} + static int berlin_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm_dev, int duty_ns, int period_ns) { @@ -137,6 +169,8 @@ 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, @@ -176,7 +210,7 @@ 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 +238,66 @@ static int berlin_pwm_remove(struct platform_device *pdev) return ret; } +#ifdef CONFIG_PM_SLEEP +static int berlin_pwm_suspend(struct device *dev) +{ + unsigned int i; + struct berlin_pwm_chip *pwm = dev_get_drvdata(dev); + + for (i = 0; i < pwm->chip.npwm; i++) { + struct pwm_device *pwm_dev = &pwm->chip.pwms[i]; + struct berlin_pwm_channel *chan = pwm_get_chip_data(pwm_dev); + + if (!chan) + continue; + + chan->enable = berlin_pwm_readl(pwm, i, BERLIN_PWM_ENABLE); + chan->ctrl = berlin_pwm_readl(pwm, i, BERLIN_PWM_CONTROL); + chan->duty = berlin_pwm_readl(pwm, i, BERLIN_PWM_DUTY); + chan->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 ret; + unsigned int i; + struct berlin_pwm_chip *pwm = dev_get_drvdata(dev); + + ret = clk_prepare_enable(pwm->clk); + if (ret) + return ret; + + for (i = 0; i < pwm->chip.npwm; i++) { + struct pwm_device *pwm_dev = &pwm->chip.pwms[i]; + struct berlin_pwm_channel *chan = pwm_get_chip_data(pwm_dev); + + if (!chan) + continue; + + berlin_pwm_writel(pwm, i, chan->ctrl, BERLIN_PWM_CONTROL); + berlin_pwm_writel(pwm, i, chan->duty, BERLIN_PWM_DUTY); + berlin_pwm_writel(pwm, i, chan->tcnt, BERLIN_PWM_TCNT); + berlin_pwm_writel(pwm, i, chan->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); -- 2.6.2
| |