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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-10 20:15:24 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-10 20:15:24 +0900
commit2474542f64432398f503373f53bdf620491bcfa8 (patch)
tree3c9744b138c2158757530814b35c23eed31cf6ce /drivers/pwm/pwm-tiecap.c
parentc7a6ced9d8e8411bdafe83998474d185a79badc3 (diff)
parent85f8879ca4f3d26a7f473522101fb74a79bda3f2 (diff)
Merge tag 'for-3.7-rc1' of git://gitorious.org/linux-pwm/linux-pwm
Pull pwm changes from Thierry Reding: "All legacy PWM providers have now been moved to the PWM subsystem. The plan for 3.8 is to adapt all board files to provide a lookup table for PWM devices in order to get rid of the global namespace. Subsequently, users of the legacy pwm_request() and pwm_free() functions can be migrated to the new pwm_get() and pwm_put() functions. Once this has been completed, the legacy API and the compatibility code in the core can be removed. In addition to the above, these changes also add support for configuring the polarity of a PWM signal (currently only supported on ECAP and EHRPWM) and include a much needed rework of the i.MX driver. Managed functions to obtain and release a PWM device (devm_pwm_get() and devm_pwm_put()) have been added and the pwm-backlight driver has been updated to use them. If the PWM subsystem hasn't been enabled, dummy functions are provided that allow the subsystem to safely compile out. Some common checks on input parameters have been moved to the core and removed from the drivers. Finally, a small fix corrects the description of the PWM specifier's second cell in the device tree representation." * tag 'for-3.7-rc1' of git://gitorious.org/linux-pwm/linux-pwm: (23 commits) pwm: dt: Fix description of second PWM cell pwm: Check for negative duty-cycle and period pwm: Add Ingenic JZ4740 support MIPS: JZ4740: Export timer API pwm: Move PUV3 PWM driver to PWM framework unicore32: pwm: Use managed resource allocations unicore32: pwm: Remove unnecessary indirection unicore32: pwm: Use module_platform_driver() unicore32: pwm: Properly remap memory-mapped registers pwm-backlight: Use devm_pwm_get() instead of pwm_get() pwm: Move AB8500 PWM driver to PWM framework pwm: Fix compilation error when CONFIG_PWM is not defined pwm: i.MX: fix clock lookup pwm: i.MX: use per clock unconditionally pwm: i.MX: add devicetree support pwm: i.MX: Use module_platform_driver pwm: i.MX: add functions to enable/disable pwm. pwm: i.MX: remove unnecessary if in pwm_[en|dis]able pwm: i.MX: factor out SoC specific functions pwm: pwm-tiehrpwm: Add support for configuring polarity of PWM ...
Diffstat (limited to 'drivers/pwm/pwm-tiecap.c')
-rw-r--r--drivers/pwm/pwm-tiecap.c24
1 files changed, 23 insertions, 1 deletions
diff --git a/drivers/pwm/pwm-tiecap.c b/drivers/pwm/pwm-tiecap.c
index 4b6688909fee..d6d4cf05565e 100644
--- a/drivers/pwm/pwm-tiecap.c
+++ b/drivers/pwm/pwm-tiecap.c
@@ -32,6 +32,7 @@
#define CAP3 0x10
#define CAP4 0x14
#define ECCTL2 0x2A
+#define ECCTL2_APWM_POL_LOW BIT(10)
#define ECCTL2_APWM_MODE BIT(9)
#define ECCTL2_SYNC_SEL_DISA (BIT(7) | BIT(6))
#define ECCTL2_TSCTR_FREERUN BIT(4)
@@ -59,7 +60,7 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned long period_cycles, duty_cycles;
unsigned int reg_val;
- if (period_ns < 0 || duty_ns < 0 || period_ns > NSEC_PER_SEC)
+ if (period_ns > NSEC_PER_SEC)
return -ERANGE;
c = pc->clk_rate;
@@ -111,6 +112,26 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
return 0;
}
+static int ecap_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm,
+ enum pwm_polarity polarity)
+{
+ struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip);
+ unsigned short reg_val;
+
+ pm_runtime_get_sync(pc->chip.dev);
+ reg_val = readw(pc->mmio_base + ECCTL2);
+ if (polarity == PWM_POLARITY_INVERSED)
+ /* Duty cycle defines LOW period of PWM */
+ reg_val |= ECCTL2_APWM_POL_LOW;
+ else
+ /* Duty cycle defines HIGH period of PWM */
+ reg_val &= ~ECCTL2_APWM_POL_LOW;
+
+ writew(reg_val, pc->mmio_base + ECCTL2);
+ pm_runtime_put_sync(pc->chip.dev);
+ return 0;
+}
+
static int ecap_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip);
@@ -157,6 +178,7 @@ static void ecap_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
static const struct pwm_ops ecap_pwm_ops = {
.free = ecap_pwm_free,
.config = ecap_pwm_config,
+ .set_polarity = ecap_pwm_set_polarity,
.enable = ecap_pwm_enable,
.disable = ecap_pwm_disable,
.owner = THIS_MODULE,