Add PM support for FTM pwm driver using callback function suspend and resume in .driver.pm of platform_driver.
Signed-off-by: Xiubo Li <[email protected]> --- drivers/pwm/pwm-fsl-ftm.c | 103 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 102 insertions(+), 1 deletion(-) diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c index 0f2cc7e..c504eb1 100644 --- a/drivers/pwm/pwm-fsl-ftm.c +++ b/drivers/pwm/pwm-fsl-ftm.c @@ -17,6 +17,7 @@ #include <linux/mutex.h> #include <linux/of_address.h> #include <linux/platform_device.h> +#include <linux/pm_runtime.h> #include <linux/pwm.h> #include <linux/regmap.h> #include <linux/slab.h> @@ -66,6 +67,8 @@ #define FTM_SWOCTRL 0x94 #define FTM_PWMLOAD 0x98 +#define FTM_NPWM 8 + enum fsl_pwm_clk { FSL_PWM_CLK_SYS, FSL_PWM_CLK_FIX, @@ -74,9 +77,22 @@ enum fsl_pwm_clk { FSL_PWM_CLK_MAX }; +struct fsl_pwm_ctx { + u32 cntin; + u32 outinit; + u32 outmask; + u32 pol; + u32 sc; + u32 mod; + u32 csc[FTM_NPWM]; + u32 cv[FTM_NPWM]; +}; + struct fsl_pwm_chip { struct pwm_chip chip; + struct fsl_pwm_ctx ctx; + struct mutex lock; unsigned int use_count; @@ -327,6 +343,9 @@ static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) int ret; mutex_lock(&fpc->lock); + if (!fpc->use_count) + pm_runtime_get_sync(chip->dev); + regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm), 0); ret = fsl_counter_clock_enable(fpc); @@ -369,7 +388,10 @@ static void fsl_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) if ((val & 0xFF) == 0xFF) fpc->period_ns = 0; + if (!fpc->use_count) + pm_runtime_put_sync(chip->dev); mutex_unlock(&fpc->lock); + } static const struct pwm_ops fsl_pwm_ops = { @@ -390,9 +412,11 @@ static int fsl_pwm_init(struct fsl_pwm_chip *fpc) if (ret) return ret; + pm_runtime_get_sync(fpc->chip.dev); regmap_write(fpc->regmap, FTM_CNTIN, 0x00); regmap_write(fpc->regmap, FTM_OUTINIT, 0x00); regmap_write(fpc->regmap, FTM_OUTMASK, 0xFF); + pm_runtime_put_sync(fpc->chip.dev); clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]); @@ -457,7 +481,7 @@ static int fsl_pwm_probe(struct platform_device *pdev) fpc->chip.of_xlate = of_pwm_xlate_with_flags; fpc->chip.of_pwm_n_cells = 3; fpc->chip.base = -1; - fpc->chip.npwm = 8; + fpc->chip.npwm = FTM_NPWM; fpc->chip.can_sleep = true; ret = pwmchip_add(&fpc->chip); @@ -466,6 +490,7 @@ static int fsl_pwm_probe(struct platform_device *pdev) return ret; } + pm_runtime_enable(&pdev->dev); platform_set_drvdata(pdev, fpc); return fsl_pwm_init(fpc); @@ -475,9 +500,84 @@ static int fsl_pwm_remove(struct platform_device *pdev) { struct fsl_pwm_chip *fpc = platform_get_drvdata(pdev); + pm_runtime_disable(&pdev->dev); return pwmchip_remove(&fpc->chip); } +#ifdef CONFIG_PM_SLEEP +static void fsl_pwm_save_ctx(struct fsl_pwm_chip *fpc) +{ + int i; + + regmap_read(fpc->regmap, FTM_CNTIN, &fpc->ctx.cntin); + regmap_read(fpc->regmap, FTM_OUTINIT, &fpc->ctx.outinit); + regmap_read(fpc->regmap, FTM_OUTMASK, &fpc->ctx.outmask); + regmap_read(fpc->regmap, FTM_POL, &fpc->ctx.pol); + regmap_read(fpc->regmap, FTM_SC, &fpc->ctx.sc); + regmap_read(fpc->regmap, FTM_MOD, &fpc->ctx.mod); + for (i = 0; i < FTM_NPWM; i++) { + regmap_read(fpc->regmap, FTM_CSC(i), &fpc->ctx.csc[i]); + regmap_read(fpc->regmap, FTM_CV(i), &fpc->ctx.cv[i]); + } +} + +static void fsl_pwm_restore_ctx(struct fsl_pwm_chip *fpc) +{ + int i; + + regmap_write(fpc->regmap, FTM_CNTIN, fpc->ctx.cntin); + regmap_write(fpc->regmap, FTM_OUTINIT, fpc->ctx.outinit); + regmap_write(fpc->regmap, FTM_OUTMASK, fpc->ctx.outmask); + regmap_write(fpc->regmap, FTM_POL, fpc->ctx.pol); + regmap_write(fpc->regmap, FTM_SC, fpc->ctx.sc); + regmap_write(fpc->regmap, FTM_MOD, fpc->ctx.mod); + for (i = 0; i < FTM_NPWM; i++) { + regmap_write(fpc->regmap, FTM_CSC(i), fpc->ctx.csc[i]); + regmap_write(fpc->regmap, FTM_CV(i), fpc->ctx.cv[i]); + } +} + +static int fsl_pwm_suspend(struct device *dev) +{ + struct fsl_pwm_chip *fpc = dev_get_drvdata(dev); + + /* Disable explicitly if PWM is running */ + if (fpc->use_count) { + fsl_pwm_save_ctx(fpc); + + clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]); + clk_disable_unprepare(fpc->clk[fpc->cnt_select]); + clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]); + pm_runtime_put_sync(dev); + } + + return 0; +} + +static int fsl_pwm_resume(struct device *dev) +{ + struct fsl_pwm_chip *fpc = dev_get_drvdata(dev); + + /* Enable explicitly if PWM was running */ + if (fpc->use_count) { + pm_runtime_get_sync(dev); + clk_prepare_enable(fpc->clk[FSL_PWM_CLK_SYS]); + clk_prepare_enable(fpc->clk[fpc->cnt_select]); + clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]); + + fsl_pwm_restore_ctx(fpc); + } else { + fsl_pwm_init(fpc); + } + + return 0; +} +#endif + +static const struct dev_pm_ops fsl_pwm_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(fsl_pwm_suspend, fsl_pwm_resume) +}; + static const struct of_device_id fsl_pwm_dt_ids[] = { { .compatible = "fsl,vf610-ftm-pwm", }, { /* sentinel */ } @@ -488,6 +588,7 @@ static struct platform_driver fsl_pwm_driver = { .driver = { .name = "fsl-ftm-pwm", .of_match_table = fsl_pwm_dt_ids, + .pm = &fsl_pwm_pm_ops, }, .probe = fsl_pwm_probe, .remove = fsl_pwm_remove, -- 2.1.0.27.g96db324 -- To unsubscribe from this list: send the line "unsubscribe linux-pwm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
