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path: root/drivers/pwm/pwm-stm32.c
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Diffstat (limited to 'drivers/pwm/pwm-stm32.c')
-rw-r--r--drivers/pwm/pwm-stm32.c63
1 files changed, 29 insertions, 34 deletions
diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c
index 794ca5b02968..bdcdb7f38312 100644
--- a/drivers/pwm/pwm-stm32.c
+++ b/drivers/pwm/pwm-stm32.c
@@ -115,14 +115,14 @@ static int stm32_pwm_raw_capture(struct stm32_pwm *priv, struct pwm_device *pwm,
int ret;
/* Ensure registers have been updated, enable counter and capture */
- regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG);
- regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, TIM_CR1_CEN);
+ regmap_set_bits(priv->regmap, TIM_EGR, TIM_EGR_UG);
+ regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
/* Use cc1 or cc3 DMA resp for PWM input channels 1 & 2 or 3 & 4 */
dma_id = pwm->hwpwm < 2 ? STM32_TIMERS_DMA_CH1 : STM32_TIMERS_DMA_CH3;
ccen = pwm->hwpwm < 2 ? TIM_CCER_CC12E : TIM_CCER_CC34E;
ccr = pwm->hwpwm < 2 ? TIM_CCR1 : TIM_CCR3;
- regmap_update_bits(priv->regmap, TIM_CCER, ccen, ccen);
+ regmap_set_bits(priv->regmap, TIM_CCER, ccen);
/*
* Timer DMA burst mode. Request 2 registers, 2 bursts, to get both
@@ -160,8 +160,8 @@ static int stm32_pwm_raw_capture(struct stm32_pwm *priv, struct pwm_device *pwm,
}
stop:
- regmap_update_bits(priv->regmap, TIM_CCER, ccen, 0);
- regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
+ regmap_clear_bits(priv->regmap, TIM_CCER, ccen);
+ regmap_clear_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
return ret;
}
@@ -359,7 +359,7 @@ static int stm32_pwm_config(struct stm32_pwm *priv, int ch,
regmap_write(priv->regmap, TIM_PSC, prescaler);
regmap_write(priv->regmap, TIM_ARR, prd - 1);
- regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, TIM_CR1_ARPE);
+ regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE);
/* Calculate the duty cycles */
dty = prd * duty_ns;
@@ -377,7 +377,7 @@ static int stm32_pwm_config(struct stm32_pwm *priv, int ch,
else
regmap_update_bits(priv->regmap, TIM_CCMR2, mask, ccmr);
- regmap_update_bits(priv->regmap, TIM_BDTR, TIM_BDTR_MOE, TIM_BDTR_MOE);
+ regmap_set_bits(priv->regmap, TIM_BDTR, TIM_BDTR_MOE);
return 0;
}
@@ -411,13 +411,13 @@ static int stm32_pwm_enable(struct stm32_pwm *priv, int ch)
if (priv->have_complementary_output)
mask |= TIM_CCER_CC1NE << (ch * 4);
- regmap_update_bits(priv->regmap, TIM_CCER, mask, mask);
+ regmap_set_bits(priv->regmap, TIM_CCER, mask);
/* Make sure that registers are updated */
- regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG);
+ regmap_set_bits(priv->regmap, TIM_EGR, TIM_EGR_UG);
/* Enable controller */
- regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, TIM_CR1_CEN);
+ regmap_set_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
return 0;
}
@@ -431,11 +431,11 @@ static void stm32_pwm_disable(struct stm32_pwm *priv, int ch)
if (priv->have_complementary_output)
mask |= TIM_CCER_CC1NE << (ch * 4);
- regmap_update_bits(priv->regmap, TIM_CCER, mask, 0);
+ regmap_clear_bits(priv->regmap, TIM_CCER, mask);
/* When all channels are disabled, we can disable the controller */
if (!active_channels(priv))
- regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0);
+ regmap_clear_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN);
clk_disable(priv->clk);
}
@@ -568,41 +568,30 @@ static void stm32_pwm_detect_complementary(struct stm32_pwm *priv)
* If complementary bit doesn't exist writing 1 will have no
* effect so we can detect it.
*/
- regmap_update_bits(priv->regmap,
- TIM_CCER, TIM_CCER_CC1NE, TIM_CCER_CC1NE);
+ regmap_set_bits(priv->regmap, TIM_CCER, TIM_CCER_CC1NE);
regmap_read(priv->regmap, TIM_CCER, &ccer);
- regmap_update_bits(priv->regmap, TIM_CCER, TIM_CCER_CC1NE, 0);
+ regmap_clear_bits(priv->regmap, TIM_CCER, TIM_CCER_CC1NE);
priv->have_complementary_output = (ccer != 0);
}
-static int stm32_pwm_detect_channels(struct stm32_pwm *priv)
+static unsigned int stm32_pwm_detect_channels(struct stm32_pwm *priv,
+ unsigned int *num_enabled)
{
- u32 ccer;
- int npwm = 0;
+ u32 ccer, ccer_backup;
/*
* If channels enable bits don't exist writing 1 will have no
* effect so we can detect and count them.
*/
- regmap_update_bits(priv->regmap,
- TIM_CCER, TIM_CCER_CCXE, TIM_CCER_CCXE);
+ regmap_read(priv->regmap, TIM_CCER, &ccer_backup);
+ regmap_set_bits(priv->regmap, TIM_CCER, TIM_CCER_CCXE);
regmap_read(priv->regmap, TIM_CCER, &ccer);
- regmap_update_bits(priv->regmap, TIM_CCER, TIM_CCER_CCXE, 0);
-
- if (ccer & TIM_CCER_CC1E)
- npwm++;
+ regmap_write(priv->regmap, TIM_CCER, ccer_backup);
- if (ccer & TIM_CCER_CC2E)
- npwm++;
+ *num_enabled = hweight32(ccer_backup & TIM_CCER_CCXE);
- if (ccer & TIM_CCER_CC3E)
- npwm++;
-
- if (ccer & TIM_CCER_CC4E)
- npwm++;
-
- return npwm;
+ return hweight32(ccer & TIM_CCER_CCXE);
}
static int stm32_pwm_probe(struct platform_device *pdev)
@@ -611,6 +600,8 @@ static int stm32_pwm_probe(struct platform_device *pdev)
struct device_node *np = dev->of_node;
struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent);
struct stm32_pwm *priv;
+ unsigned int num_enabled;
+ unsigned int i;
int ret;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
@@ -633,7 +624,11 @@ static int stm32_pwm_probe(struct platform_device *pdev)
priv->chip.dev = dev;
priv->chip.ops = &stm32pwm_ops;
- priv->chip.npwm = stm32_pwm_detect_channels(priv);
+ priv->chip.npwm = stm32_pwm_detect_channels(priv, &num_enabled);
+
+ /* Initialize clock refcount to number of enabled PWM channels. */
+ for (i = 0; i < num_enabled; i++)
+ clk_enable(priv->clk);
ret = pwmchip_add(&priv->chip);
if (ret < 0)