summaryrefslogtreecommitdiff
path: root/drivers/pwm/pwm-tiehrpwm.c
diff options
context:
space:
mode:
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-tiehrpwm.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-tiehrpwm.c')
-rw-r--r--drivers/pwm/pwm-tiehrpwm.c75
1 files changed, 52 insertions, 23 deletions
diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c
index b1996bcd5b78..d3c1dff0a0dc 100644
--- a/drivers/pwm/pwm-tiehrpwm.c
+++ b/drivers/pwm/pwm-tiehrpwm.c
@@ -81,6 +81,15 @@
#define AQCTL_ZRO_FRCHIGH BIT(1)
#define AQCTL_ZRO_FRCTOGGLE (BIT(1) | BIT(0))
+#define AQCTL_CHANA_POLNORMAL (AQCTL_CAU_FRCLOW | AQCTL_PRD_FRCHIGH | \
+ AQCTL_ZRO_FRCHIGH)
+#define AQCTL_CHANA_POLINVERSED (AQCTL_CAU_FRCHIGH | AQCTL_PRD_FRCLOW | \
+ AQCTL_ZRO_FRCLOW)
+#define AQCTL_CHANB_POLNORMAL (AQCTL_CBU_FRCLOW | AQCTL_PRD_FRCHIGH | \
+ AQCTL_ZRO_FRCHIGH)
+#define AQCTL_CHANB_POLINVERSED (AQCTL_CBU_FRCHIGH | AQCTL_PRD_FRCLOW | \
+ AQCTL_ZRO_FRCLOW)
+
#define AQSFRC_RLDCSF_MASK (BIT(7) | BIT(6))
#define AQSFRC_RLDCSF_ZRO 0
#define AQSFRC_RLDCSF_PRD BIT(6)
@@ -105,6 +114,7 @@ struct ehrpwm_pwm_chip {
unsigned int clk_rate;
void __iomem *mmio_base;
unsigned long period_cycles[NUM_PWM_CHANNEL];
+ enum pwm_polarity polarity[NUM_PWM_CHANNEL];
};
static inline struct ehrpwm_pwm_chip *to_ehrpwm_pwm_chip(struct pwm_chip *chip)
@@ -165,39 +175,37 @@ static int set_prescale_div(unsigned long rqst_prescaler,
return 1;
}
-static void configure_chans(struct ehrpwm_pwm_chip *pc, int chan,
- unsigned long duty_cycles)
+static void configure_polarity(struct ehrpwm_pwm_chip *pc, int chan)
{
- int cmp_reg, aqctl_reg;
+ int aqctl_reg;
unsigned short aqctl_val, aqctl_mask;
/*
- * Channels can be configured from action qualifier module.
- * Channel 0 configured with compare A register and for
- * up-counter mode.
- * Channel 1 configured with compare B register and for
- * up-counter mode.
+ * Configure PWM output to HIGH/LOW level on counter
+ * reaches compare register value and LOW/HIGH level
+ * on counter value reaches period register value and
+ * zero value on counter
*/
if (chan == 1) {
aqctl_reg = AQCTLB;
- cmp_reg = CMPB;
- /* Configure PWM Low from compare B value */
- aqctl_val = AQCTL_CBU_FRCLOW;
aqctl_mask = AQCTL_CBU_MASK;
+
+ if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
+ aqctl_val = AQCTL_CHANB_POLINVERSED;
+ else
+ aqctl_val = AQCTL_CHANB_POLNORMAL;
} else {
- cmp_reg = CMPA;
aqctl_reg = AQCTLA;
- /* Configure PWM Low from compare A value*/
- aqctl_val = AQCTL_CAU_FRCLOW;
aqctl_mask = AQCTL_CAU_MASK;
+
+ if (pc->polarity[chan] == PWM_POLARITY_INVERSED)
+ aqctl_val = AQCTL_CHANA_POLINVERSED;
+ else
+ aqctl_val = AQCTL_CHANA_POLNORMAL;
}
- /* Configure PWM High from period value and zero value */
- aqctl_val |= AQCTL_PRD_FRCHIGH | AQCTL_ZRO_FRCHIGH;
aqctl_mask |= AQCTL_PRD_MASK | AQCTL_ZRO_MASK;
- ehrpwm_modify(pc->mmio_base, aqctl_reg, aqctl_mask, aqctl_val);
-
- ehrpwm_write(pc->mmio_base, cmp_reg, duty_cycles);
+ ehrpwm_modify(pc->mmio_base, aqctl_reg, aqctl_mask, aqctl_val);
}
/*
@@ -211,9 +219,9 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned long long c;
unsigned long period_cycles, duty_cycles;
unsigned short ps_divval, tb_divval;
- int i;
+ int i, cmp_reg;
- if (period_ns < 0 || duty_ns < 0 || period_ns > NSEC_PER_SEC)
+ if (period_ns > NSEC_PER_SEC)
return -ERANGE;
c = pc->clk_rate;
@@ -278,12 +286,29 @@ static int ehrpwm_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_CTRMODE_MASK,
TBCTL_CTRMODE_UP);
- /* Configure the channel for duty cycle */
- configure_chans(pc, pwm->hwpwm, duty_cycles);
+ if (pwm->hwpwm == 1)
+ /* Channel 1 configured with compare B register */
+ cmp_reg = CMPB;
+ else
+ /* Channel 0 configured with compare A register */
+ cmp_reg = CMPA;
+
+ ehrpwm_write(pc->mmio_base, cmp_reg, duty_cycles);
+
pm_runtime_put_sync(chip->dev);
return 0;
}
+static int ehrpwm_pwm_set_polarity(struct pwm_chip *chip,
+ struct pwm_device *pwm, enum pwm_polarity polarity)
+{
+ struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
+
+ /* Configuration of polarity in hardware delayed, do at enable */
+ pc->polarity[pwm->hwpwm] = polarity;
+ return 0;
+}
+
static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct ehrpwm_pwm_chip *pc = to_ehrpwm_pwm_chip(chip);
@@ -307,6 +332,9 @@ static int ehrpwm_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
ehrpwm_modify(pc->mmio_base, AQCSFRC, aqcsfrc_mask, aqcsfrc_val);
+ /* Channels polarity can be configured from action qualifier module */
+ configure_polarity(pc, pwm->hwpwm);
+
/* Enable time counter for free_run */
ehrpwm_modify(pc->mmio_base, TBCTL, TBCTL_RUN_MASK, TBCTL_FREE_RUN);
return 0;
@@ -358,6 +386,7 @@ static void ehrpwm_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
static const struct pwm_ops ehrpwm_pwm_ops = {
.free = ehrpwm_pwm_free,
.config = ehrpwm_pwm_config,
+ .set_polarity = ehrpwm_pwm_set_polarity,
.enable = ehrpwm_pwm_enable,
.disable = ehrpwm_pwm_disable,
.owner = THIS_MODULE,