diff options
| author | Philip Avinash <avinashphilip@ti.com> | 2013-01-17 10:20:03 +0100 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@avionic-design.de> | 2013-01-17 16:52:59 +0100 |
| commit | 0d75c203effefa4f62ca4d30bf52bd9ec246717f (patch) | |
| tree | 1584cc1c0f5fc3fb374f006a2cd1a5ede9053629 /drivers/pwm | |
| parent | pwm: pwm-tiehrpwm: Low power sleep support (diff) | |
| download | linux-0d75c203effefa4f62ca4d30bf52bd9ec246717f.tar.xz linux-0d75c203effefa4f62ca4d30bf52bd9ec246717f.zip | |
pwm: pwm-tiecap: Low power sleep support
In low power modes of AM33XX platforms, peripherals power is cut off.
This patch supports low power sleep transition support for ECAP driver.
Signed-off-by: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Diffstat (limited to 'drivers/pwm')
| -rw-r--r-- | drivers/pwm/pwm-tiecap.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-tiecap.c b/drivers/pwm/pwm-tiecap.c index 5cf016dd9822..05b676db88e6 100644 --- a/drivers/pwm/pwm-tiecap.c +++ b/drivers/pwm/pwm-tiecap.c @@ -41,10 +41,17 @@ #define ECCTL2_SYNC_SEL_DISA (BIT(7) | BIT(6)) #define ECCTL2_TSCTR_FREERUN BIT(4) +struct ecap_context { + u32 cap3; + u32 cap4; + u16 ecctl2; +}; + struct ecap_pwm_chip { struct pwm_chip chip; unsigned int clk_rate; void __iomem *mmio_base; + struct ecap_context ctx; }; static inline struct ecap_pwm_chip *to_ecap_pwm_chip(struct pwm_chip *chip) @@ -288,11 +295,57 @@ static int ecap_pwm_remove(struct platform_device *pdev) return pwmchip_remove(&pc->chip); } +void ecap_pwm_save_context(struct ecap_pwm_chip *pc) +{ + pm_runtime_get_sync(pc->chip.dev); + pc->ctx.ecctl2 = readw(pc->mmio_base + ECCTL2); + pc->ctx.cap4 = readl(pc->mmio_base + CAP4); + pc->ctx.cap3 = readl(pc->mmio_base + CAP3); + pm_runtime_put_sync(pc->chip.dev); +} + +void ecap_pwm_restore_context(struct ecap_pwm_chip *pc) +{ + writel(pc->ctx.cap3, pc->mmio_base + CAP3); + writel(pc->ctx.cap4, pc->mmio_base + CAP4); + writew(pc->ctx.ecctl2, pc->mmio_base + ECCTL2); +} + +static int ecap_pwm_suspend(struct device *dev) +{ + struct ecap_pwm_chip *pc = dev_get_drvdata(dev); + struct pwm_device *pwm = pc->chip.pwms; + + ecap_pwm_save_context(pc); + + /* Disable explicitly if PWM is running */ + if (test_bit(PWMF_ENABLED, &pwm->flags)) + pm_runtime_put_sync(dev); + + return 0; +} + +static int ecap_pwm_resume(struct device *dev) +{ + struct ecap_pwm_chip *pc = dev_get_drvdata(dev); + struct pwm_device *pwm = pc->chip.pwms; + + /* Enable explicitly if PWM was running */ + if (test_bit(PWMF_ENABLED, &pwm->flags)) + pm_runtime_get_sync(dev); + + ecap_pwm_restore_context(pc); + return 0; +} + +static SIMPLE_DEV_PM_OPS(ecap_pwm_pm_ops, ecap_pwm_suspend, ecap_pwm_resume); + static struct platform_driver ecap_pwm_driver = { .driver = { .name = "ecap", .owner = THIS_MODULE, .of_match_table = ecap_of_match, + .pm = &ecap_pwm_pm_ops, }, .probe = ecap_pwm_probe, .remove = ecap_pwm_remove, |