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-rw-r--r--drivers/pwm/pwm-ab8500.c112
-rw-r--r--drivers/pwm/pwm-dwc.c38
-rw-r--r--drivers/pwm/pwm-iqs620a.c4
-rw-r--r--drivers/pwm/pwm-lp3943.c1
-rw-r--r--drivers/pwm/pwm-sifive.c8
-rw-r--r--drivers/pwm/pwm-stm32-lp.c2
6 files changed, 134 insertions, 31 deletions
diff --git a/drivers/pwm/pwm-ab8500.c b/drivers/pwm/pwm-ab8500.c
index ad37bc46f272..507ff0d5f7bd 100644
--- a/drivers/pwm/pwm-ab8500.c
+++ b/drivers/pwm/pwm-ab8500.c
@@ -3,6 +3,7 @@
* Copyright (C) ST-Ericsson SA 2010
*
* Author: Arun R Murthy <arun.murthy@stericsson.com>
+ * Datasheet: https://web.archive.org/web/20130614115108/http://www.stericsson.com/developers/CD00291561_UM1031_AB8500_user_manual-rev5_CTDS_public.pdf
*/
#include <linux/err.h>
#include <linux/platform_device.h>
@@ -20,6 +21,8 @@
#define AB8500_PWM_OUT_CTRL2_REG 0x61
#define AB8500_PWM_OUT_CTRL7_REG 0x66
+#define AB8500_PWM_CLKRATE 9600000
+
struct ab8500_pwm_chip {
struct pwm_chip chip;
unsigned int hwid;
@@ -35,13 +38,60 @@ static int ab8500_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
{
int ret;
u8 reg;
- unsigned int higher_val, lower_val;
+ u8 higher_val, lower_val;
+ unsigned int duty_steps, div;
struct ab8500_pwm_chip *ab8500 = ab8500_pwm_from_chip(chip);
if (state->polarity != PWM_POLARITY_NORMAL)
return -EINVAL;
- if (!state->enabled) {
+ if (state->enabled) {
+ /*
+ * A time quantum is
+ * q = (32 - FreqPWMOutx[3:0]) / AB8500_PWM_CLKRATE
+ * The period is always 1024 q, duty_cycle is between 1q and 1024q.
+ *
+ * FreqPWMOutx[3:0] | output frequency | output frequency | 1024q = period
+ * | (from manual) | (1 / 1024q) | = 1 / freq
+ * -----------------+------------------+------------------+--------------
+ * b0000 | 293 Hz | 292.968750 Hz | 3413333.33 ns
+ * b0001 | 302 Hz | 302.419355 Hz | 3306666.66 ns
+ * b0010 | 312 Hz | 312.500000 Hz | 3200000 ns
+ * b0011 | 323 Hz | 323.275862 Hz | 3093333.33 ns
+ * b0100 | 334 Hz | 334.821429 Hz | 2986666.66 ns
+ * b0101 | 347 Hz | 347.222222 Hz | 2880000 ns
+ * b0110 | 360 Hz | 360.576923 Hz | 2773333.33 ns
+ * b0111 | 375 Hz | 375.000000 Hz | 2666666.66 ns
+ * b1000 | 390 Hz | 390.625000 Hz | 2560000 ns
+ * b1001 | 407 Hz | 407.608696 Hz | 2453333.33 ns
+ * b1010 | 426 Hz | 426.136364 Hz | 2346666.66 ns
+ * b1011 | 446 Hz | 446.428571 Hz | 2240000 ns
+ * b1100 | 468 Hz | 468.750000 Hz | 2133333.33 ns
+ * b1101 | 493 Hz | 493.421053 Hz | 2026666.66 ns
+ * b1110 | 520 Hz | 520.833333 Hz | 1920000 ns
+ * b1111 | 551 Hz | 551.470588 Hz | 1813333.33 ns
+ *
+ *
+ * AB8500_PWM_CLKRATE is a multiple of 1024, so the division by
+ * 1024 can be done in this factor without loss of precision.
+ */
+ div = min_t(u64, mul_u64_u64_div_u64(state->period,
+ AB8500_PWM_CLKRATE >> 10,
+ NSEC_PER_SEC), 32); /* 32 - FreqPWMOutx[3:0] */
+ if (div <= 16)
+ /* requested period < 3413333.33 */
+ return -EINVAL;
+
+ duty_steps = max_t(u64, mul_u64_u64_div_u64(state->duty_cycle,
+ AB8500_PWM_CLKRATE,
+ (u64)NSEC_PER_SEC * div), 1024);
+ }
+
+ /*
+ * The hardware doesn't support duty_steps = 0 explicitly, but emits low
+ * when disabled.
+ */
+ if (!state->enabled || duty_steps == 0) {
ret = abx500_mask_and_set_register_interruptible(chip->dev,
AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
1 << ab8500->hwid, 0);
@@ -53,28 +103,29 @@ static int ab8500_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
}
/*
- * get the first 8 bits that are be written to
+ * The lower 8 bits of duty_steps is written to ...
* AB8500_PWM_OUT_CTRL1_REG[0:7]
*/
- lower_val = state->duty_cycle & 0x00FF;
+ lower_val = (duty_steps - 1) & 0x00ff;
/*
- * get bits [9:10] that are to be written to
- * AB8500_PWM_OUT_CTRL2_REG[0:1]
+ * The two remaining high bits to
+ * AB8500_PWM_OUT_CTRL2_REG[0:1]; together with FreqPWMOutx.
*/
- higher_val = ((state->duty_cycle & 0x0300) >> 8);
+ higher_val = ((duty_steps - 1) & 0x0300) >> 8 | (32 - div) << 4;
reg = AB8500_PWM_OUT_CTRL1_REG + (ab8500->hwid * 2);
ret = abx500_set_register_interruptible(chip->dev, AB8500_MISC,
- reg, (u8)lower_val);
+ reg, lower_val);
if (ret < 0)
return ret;
ret = abx500_set_register_interruptible(chip->dev, AB8500_MISC,
- (reg + 1), (u8)higher_val);
+ (reg + 1), higher_val);
if (ret < 0)
return ret;
+ /* enable */
ret = abx500_mask_and_set_register_interruptible(chip->dev,
AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
1 << ab8500->hwid, 1 << ab8500->hwid);
@@ -85,8 +136,51 @@ static int ab8500_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
return ret;
}
+static int ab8500_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ u8 ctrl7, lower_val, higher_val;
+ int ret;
+ struct ab8500_pwm_chip *ab8500 = ab8500_pwm_from_chip(chip);
+ unsigned int div, duty_steps;
+
+ ret = abx500_get_register_interruptible(chip->dev, AB8500_MISC,
+ AB8500_PWM_OUT_CTRL7_REG,
+ &ctrl7);
+ if (ret)
+ return ret;
+
+ state->polarity = PWM_POLARITY_NORMAL;
+
+ if (!(ctrl7 & 1 << ab8500->hwid)) {
+ state->enabled = false;
+ return 0;
+ }
+
+ ret = abx500_get_register_interruptible(chip->dev, AB8500_MISC,
+ AB8500_PWM_OUT_CTRL1_REG + (ab8500->hwid * 2),
+ &lower_val);
+ if (ret)
+ return ret;
+
+ ret = abx500_get_register_interruptible(chip->dev, AB8500_MISC,
+ AB8500_PWM_OUT_CTRL2_REG + (ab8500->hwid * 2),
+ &higher_val);
+ if (ret)
+ return ret;
+
+ div = 32 - ((higher_val & 0xf0) >> 4);
+ duty_steps = ((higher_val & 3) << 8 | lower_val) + 1;
+
+ state->period = DIV64_U64_ROUND_UP((u64)div << 10, AB8500_PWM_CLKRATE);
+ state->duty_cycle = DIV64_U64_ROUND_UP((u64)div * duty_steps, AB8500_PWM_CLKRATE);
+
+ return 0;
+}
+
static const struct pwm_ops ab8500_pwm_ops = {
.apply = ab8500_pwm_apply,
+ .get_state = ab8500_pwm_get_state,
.owner = THIS_MODULE,
};
diff --git a/drivers/pwm/pwm-dwc.c b/drivers/pwm/pwm-dwc.c
index bd2308812096..3bbb26c862c3 100644
--- a/drivers/pwm/pwm-dwc.c
+++ b/drivers/pwm/pwm-dwc.c
@@ -198,20 +198,35 @@ static const struct pwm_ops dwc_pwm_ops = {
.owner = THIS_MODULE,
};
+static struct dwc_pwm *dwc_pwm_alloc(struct device *dev)
+{
+ struct dwc_pwm *dwc;
+
+ dwc = devm_kzalloc(dev, sizeof(*dwc), GFP_KERNEL);
+ if (!dwc)
+ return NULL;
+
+ dwc->chip.dev = dev;
+ dwc->chip.ops = &dwc_pwm_ops;
+ dwc->chip.npwm = DWC_TIMERS_TOTAL;
+
+ dev_set_drvdata(dev, dwc);
+ return dwc;
+}
+
static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
{
struct device *dev = &pci->dev;
struct dwc_pwm *dwc;
int ret;
- dwc = devm_kzalloc(&pci->dev, sizeof(*dwc), GFP_KERNEL);
+ dwc = dwc_pwm_alloc(dev);
if (!dwc)
return -ENOMEM;
ret = pcim_enable_device(pci);
if (ret) {
- dev_err(&pci->dev,
- "Failed to enable device (%pe)\n", ERR_PTR(ret));
+ dev_err(dev, "Failed to enable device (%pe)\n", ERR_PTR(ret));
return ret;
}
@@ -219,24 +234,17 @@ static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
ret = pcim_iomap_regions(pci, BIT(0), pci_name(pci));
if (ret) {
- dev_err(&pci->dev,
- "Failed to iomap PCI BAR (%pe)\n", ERR_PTR(ret));
+ dev_err(dev, "Failed to iomap PCI BAR (%pe)\n", ERR_PTR(ret));
return ret;
}
dwc->base = pcim_iomap_table(pci)[0];
if (!dwc->base) {
- dev_err(&pci->dev, "Base address missing\n");
+ dev_err(dev, "Base address missing\n");
return -ENOMEM;
}
- pci_set_drvdata(pci, dwc);
-
- dwc->chip.dev = dev;
- dwc->chip.ops = &dwc_pwm_ops;
- dwc->chip.npwm = DWC_TIMERS_TOTAL;
-
- ret = pwmchip_add(&dwc->chip);
+ ret = devm_pwmchip_add(dev, &dwc->chip);
if (ret)
return ret;
@@ -248,12 +256,8 @@ static int dwc_pwm_probe(struct pci_dev *pci, const struct pci_device_id *id)
static void dwc_pwm_remove(struct pci_dev *pci)
{
- struct dwc_pwm *dwc = pci_get_drvdata(pci);
-
pm_runtime_forbid(&pci->dev);
pm_runtime_get_noresume(&pci->dev);
-
- pwmchip_remove(&dwc->chip);
}
#ifdef CONFIG_PM_SLEEP
diff --git a/drivers/pwm/pwm-iqs620a.c b/drivers/pwm/pwm-iqs620a.c
index 4987ca940b64..8362b4870c66 100644
--- a/drivers/pwm/pwm-iqs620a.c
+++ b/drivers/pwm/pwm-iqs620a.c
@@ -55,8 +55,8 @@ static int iqs620_pwm_init(struct iqs620_pwm_private *iqs620_pwm,
if (ret)
return ret;
- return regmap_update_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
- IQS620_PWR_SETTINGS_PWM_OUT, 0xff);
+ return regmap_set_bits(iqs62x->regmap, IQS620_PWR_SETTINGS,
+ IQS620_PWR_SETTINGS_PWM_OUT);
}
static int iqs620_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
diff --git a/drivers/pwm/pwm-lp3943.c b/drivers/pwm/pwm-lp3943.c
index 215ef9069114..35675e4058c6 100644
--- a/drivers/pwm/pwm-lp3943.c
+++ b/drivers/pwm/pwm-lp3943.c
@@ -8,7 +8,6 @@
*/
#include <linux/err.h>
-#include <linux/i2c.h>
#include <linux/mfd/lp3943.h>
#include <linux/module.h>
#include <linux/platform_device.h>
diff --git a/drivers/pwm/pwm-sifive.c b/drivers/pwm/pwm-sifive.c
index 62b6acc6373d..393a4b97fc19 100644
--- a/drivers/pwm/pwm-sifive.c
+++ b/drivers/pwm/pwm-sifive.c
@@ -161,7 +161,13 @@ static int pwm_sifive_apply(struct pwm_chip *chip, struct pwm_device *pwm,
mutex_lock(&ddata->lock);
if (state->period != ddata->approx_period) {
- if (ddata->user_count != 1) {
+ /*
+ * Don't let a 2nd user change the period underneath the 1st user.
+ * However if ddate->approx_period == 0 this is the first time we set
+ * any period, so let whoever gets here first set the period so other
+ * users who agree on the period won't fail.
+ */
+ if (ddata->user_count != 1 && ddata->approx_period) {
mutex_unlock(&ddata->lock);
return -EBUSY;
}
diff --git a/drivers/pwm/pwm-stm32-lp.c b/drivers/pwm/pwm-stm32-lp.c
index 514ff58a4471..f315fa106be8 100644
--- a/drivers/pwm/pwm-stm32-lp.c
+++ b/drivers/pwm/pwm-stm32-lp.c
@@ -127,7 +127,7 @@ static int stm32_pwm_lp_apply(struct pwm_chip *chip, struct pwm_device *pwm,
/* ensure CMP & ARR registers are properly written */
ret = regmap_read_poll_timeout(priv->regmap, STM32_LPTIM_ISR, val,
- (val & STM32_LPTIM_CMPOK_ARROK),
+ (val & STM32_LPTIM_CMPOK_ARROK) == STM32_LPTIM_CMPOK_ARROK,
100, 1000);
if (ret) {
dev_err(priv->chip.dev, "ARR/CMP registers write issue\n");
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