Merge tag 'pwm/for-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

Pull pwm updates from Thierry Reding:
"This contains a bunch of cleanups and simplifications across the
board, as well as a number of small fixes.

Perhaps the most notable change here is the addition of an API that
allows PWMs to be used in atomic contexts, which is useful when time-
critical operations are involved, such as using a PWM to generate IR
signals.

Finally, I have decided to step down as PWM subsystem maintainer. Due
to other responsibilities I have lately not been able to find the time
that the subsystem deserves and Uwe, who has been helping out a lot
for the past few years and has many things planned for the future, has
kindly volunteered to take over. I have no doubt that he will be a
suitable replacement"

* tag 'pwm/for-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (44 commits)
MAINTAINERS: pwm: Thierry steps down, Uwe takes over
pwm: linux/pwm.h: fix Excess kernel-doc description warning
pwm: Add pwm_apply_state() compatibility stub
pwm: cros-ec: Drop documentation for dropped struct member
pwm: Drop two unused API functions
pwm: lpc18xx-sct: Don't modify the cached period of other PWM outputs
pwm: meson: Simplify using dev_err_probe()
pwm: stmpe: Silence duplicate error messages
pwm: Reduce number of pointer dereferences in pwm_device_request()
pwm: crc: Use consistent variable naming for driver data
pwm: omap-dmtimer: Drop locking
dt-bindings: pwm: ti,pwm-omap-dmtimer: Update binding for yaml
media: pwm-ir-tx: Trigger edges from hrtimer interrupt context
pwm: bcm2835: Allow PWM driver to be used in atomic context
pwm: Make it possible to apply PWM changes in atomic context
pwm: renesas: Remove unused include
pwm: Replace ENOTSUPP with EOPNOTSUPP
pwm: Rename pwm_apply_state() to pwm_apply_might_sleep()
pwm: Stop referencing pwm->chip
pwm: Update kernel doc for struct pwm_chip
...

Documentation/devicetree/bindings/pwm/mediatek,pwm-disp.yaml

···
 
 maintainers:
   - Jitao Shi <[e-mail]>
-  - Xinlei Lee <[e-mail]>
 
 allOf:
   - $ref: pwm.yaml#

Documentation/devicetree/bindings/pwm/pwm-omap-dmtimer.txt

···
-* OMAP PWM for dual-mode timers
-
-Required properties:
-- compatible: Shall contain "ti,omap-dmtimer-pwm".
-- ti,timers: phandle to PWM capable OMAP timer. See timer/ti,timer-dm.yaml for info
-  about these timers.
-- #pwm-cells: Should be 3. See pwm.yaml in this directory for a description of
-  the cells format.
-
-Optional properties:
-- ti,prescaler: Should be a value between 0 and 7, see the timers datasheet
-- ti,clock-source: Set dmtimer parent clock, values between 0 and 2:
-  - 0x00 - high-frequency system clock (timer_sys_ck)
-  - 0x01 - 32-kHz always-on clock (timer_32k_ck)
-  - 0x02 - external clock (timer_ext_ck, OMAP2 only)
-
-Example:
-	pwm9: dmtimer-pwm@9 {
-		compatible = "ti,omap-dmtimer-pwm";
-		ti,timers = <&timer9>;
-		#pwm-cells = <3>;
-	};

Documentation/devicetree/bindings/pwm/ti,omap-dmtimer-pwm.yaml

···
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/ti,omap-dmtimer-pwm.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: TI dual mode timer PWM controller
+
+maintainers:
+  - Tony Lindgren <[e-mail]>
+
+description:
+  TI dual mode timer instances have an IO pin for PWM capability
+
+allOf:
+  - $ref: pwm.yaml#
+
+properties:
+  compatible:
+    const: ti,omap-dmtimer-pwm
+
+  "#pwm-cells":
+    const: 3
+
+  ti,timers:
+    description: Timer instance phandle for the PWM
+    $ref: /schemas/types.yaml#/definitions/phandle
+
+  ti,prescaler:
+    description: |
+      Legacy clock prescaler for timer. The timer counter is prescaled
+      with 2^n where n is the prescaler.
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [ 0, 1, 2, 3, 4, 5, 6, 7 ]
+    deprecated: true
+
+  ti,clock-source:
+    description: |
+      Legacy clock for timer, please use assigned-clocks instead.
+      0x00 - high-frequency system clock (timer_sys_ck)
+      0x01 - 32-kHz always-on clock (timer_32k_ck)
+      0x02 - external clock (timer_ext_ck, OMAP2 only)
+    $ref: /schemas/types.yaml#/definitions/uint32
+    enum: [ 0, 1, 2 ]
+    deprecated: true
+
+required:
+  - compatible
+  - ti,timers
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    pwm9: pwm {
+      compatible = "ti,omap-dmtimer-pwm";
+      ti,timers = <&timer9>;
+      #pwm-cells = <3>;
+    };

Documentation/driver-api/pwm.rst

···
 
 After being requested, a PWM has to be configured using::
 
-	int pwm_apply_state(struct pwm_device *pwm, struct pwm_state *state);
+	int pwm_apply_might_sleep(struct pwm_device *pwm, struct pwm_state *state);
 
 This API controls both the PWM period/duty_cycle config and the
 enable/disable state.
+
+PWM devices can be used from atomic context, if the PWM does not sleep. You
+can check if this the case with::
+
+        bool pwm_might_sleep(struct pwm_device *pwm);
+
+If false, the PWM can also be configured from atomic context with::
+
+	int pwm_apply_atomic(struct pwm_device *pwm, struct pwm_state *state);
 
 As a consumer, don't rely on the output's state for a disabled PWM. If it's
 easily possible, drivers are supposed to emit the inactive state, but some
···
 EMI by phase shifting the individual channels of a chip.
 
 The pwm_config(), pwm_enable() and pwm_disable() functions are just wrappers
-around pwm_apply_state() and should not be used if the user wants to change
+around pwm_apply_might_sleep() and should not be used if the user wants to change
 several parameter at once. For example, if you see pwm_config() and
 pwm_{enable,disable}() calls in the same function, this probably means you
-should switch to pwm_apply_state().
+should switch to pwm_apply_might_sleep().
 
 The PWM user API also allows one to query the PWM state that was passed to the
-last invocation of pwm_apply_state() using pwm_get_state(). Note this is
+last invocation of pwm_apply_might_sleep() using pwm_get_state(). Note this is
 different to what the driver has actually implemented if the request cannot be
 satisfied exactly with the hardware in use. There is currently no way for
 consumers to get the actually implemented settings.

MAINTAINERS

···
 F:	drivers/media/rc/pwm-ir-tx.c
 
 PWM SUBSYSTEM
-M:	Thierry Reding <[e-mail]>
-R:	Uwe Kleine-König <[e-mail]>
+M:	Uwe Kleine-König <[e-mail]>
 L:	[e-mail]
 S:	Maintained
 Q:	https://patchwork.ozlabs.org/project/linux-pwm/list/
-T:	git git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm.git
+T:	git https://git.kernel.org/pub/scm/linux/kernel/git/ukleinek/linux.git
 F:	Documentation/devicetree/bindings/gpio/gpio-mvebu.yaml
 F:	Documentation/devicetree/bindings/pwm/
 F:	Documentation/driver-api/pwm.rst
···
 F:	include/dt-bindings/pwm/
 F:	include/linux/pwm.h
 F:	include/linux/pwm_backlight.h
-K:	pwm_(config|apply_state|ops)
+K:	pwm_(config|apply_might_sleep|apply_atomic|ops)
 
 PXA GPIO DRIVER
 M:	Robert Jarzmik <[e-mail]>

drivers/gpu/drm/i915/display/intel_backlight.c

···
 	struct intel_panel *panel = &to_intel_connector(conn_state->connector)->panel;
 
 	pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
-	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
+	pwm_apply_might_sleep(panel->backlight.pwm, &panel->backlight.pwm_state);
 }
 
 static void
···
 	intel_backlight_set_pwm_level(old_conn_state, level);
 
 	panel->backlight.pwm_state.enabled = false;
-	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
+	pwm_apply_might_sleep(panel->backlight.pwm, &panel->backlight.pwm_state);
 }
 
 void intel_backlight_disable(const struct drm_connector_state *old_conn_state)
···
 
 	pwm_set_relative_duty_cycle(&panel->backlight.pwm_state, level, 100);
 	panel->backlight.pwm_state.enabled = true;
-	pwm_apply_state(panel->backlight.pwm, &panel->backlight.pwm_state);
+	pwm_apply_might_sleep(panel->backlight.pwm, &panel->backlight.pwm_state);
 }
 
 static void __intel_backlight_enable(const struct intel_crtc_state *crtc_state,

drivers/gpu/drm/solomon/ssd130x.c

···
 
 	pwm_init_state(ssd130x->pwm, &pwmstate);
 	pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
-	pwm_apply_state(ssd130x->pwm, &pwmstate);
+	pwm_apply_might_sleep(ssd130x->pwm, &pwmstate);
 
 	/* Enable the PWM */
 	pwm_enable(ssd130x->pwm);

drivers/hwmon/pwm-fan.c

···
 	}
 
 	state->enabled = true;
-	ret = pwm_apply_state(ctx->pwm, state);
+	ret = pwm_apply_might_sleep(ctx->pwm, state);
 	if (ret) {
 		dev_err(ctx->dev, "failed to enable PWM\n");
 		goto disable_regulator;
···
 
 	state->enabled = false;
 	state->duty_cycle = 0;
-	ret = pwm_apply_state(ctx->pwm, state);
+	ret = pwm_apply_might_sleep(ctx->pwm, state);
 	if (ret) {
 		dev_err(ctx->dev, "failed to disable PWM\n");
 		return ret;
···
 
 		period = state->period;
 		state->duty_cycle = DIV_ROUND_UP(pwm * (period - 1), MAX_PWM);
-		ret = pwm_apply_state(ctx->pwm, state);
+		ret = pwm_apply_might_sleep(ctx->pwm, state);
 		if (ret)
 			return ret;
 		ret = pwm_fan_power_on(ctx);
···
 						    state,
 						    &enable_regulator);
 
-			pwm_apply_state(ctx->pwm, state);
+			pwm_apply_might_sleep(ctx->pwm, state);
 			pwm_fan_switch_power(ctx, enable_regulator);
 			pwm_fan_update_state(ctx, 0);
 		}

drivers/input/misc/da7280.c

···
 		state.duty_cycle = period_mag_multi;
 	}
 
-	error = pwm_apply_state(haptics->pwm_dev, &state);
+	error = pwm_apply_might_sleep(haptics->pwm_dev, &state);
 	if (error)
 		dev_err(haptics->dev, "Failed to apply pwm state: %d\n", error);
 
···
 		/* Sync up PWM state and ensure it is off. */
 		pwm_init_state(haptics->pwm_dev, &state);
 		state.enabled = false;
-		error = pwm_apply_state(haptics->pwm_dev, &state);
+		error = pwm_apply_might_sleep(haptics->pwm_dev, &state);
 		if (error) {
 			dev_err(dev, "Failed to apply PWM state: %d\n", error);
 			return error;

drivers/input/misc/pwm-beeper.c

···
 	state.period = period;
 	pwm_set_relative_duty_cycle(&state, 50, 100);
 
-	error = pwm_apply_state(beeper->pwm, &state);
+	error = pwm_apply_might_sleep(beeper->pwm, &state);
 	if (error)
 		return error;
 
···
 	/* Sync up PWM state and ensure it is off. */
 	pwm_init_state(beeper->pwm, &state);
 	state.enabled = false;
-	error = pwm_apply_state(beeper->pwm, &state);
+	error = pwm_apply_might_sleep(beeper->pwm, &state);
 	if (error) {
 		dev_err(dev, "failed to apply initial PWM state: %d\n",
 			error);

drivers/input/misc/pwm-vibra.c

···
 	pwm_set_relative_duty_cycle(&state, vibrator->level, 0xffff);
 	state.enabled = true;
 
-	err = pwm_apply_state(vibrator->pwm, &state);
+	err = pwm_apply_might_sleep(vibrator->pwm, &state);
 	if (err) {
 		dev_err(pdev, "failed to apply pwm state: %d\n", err);
 		return err;
···
 		state.duty_cycle = vibrator->direction_duty_cycle;
 		state.enabled = true;
 
-		err = pwm_apply_state(vibrator->pwm_dir, &state);
+		err = pwm_apply_might_sleep(vibrator->pwm_dir, &state);
 		if (err) {
 			dev_err(pdev, "failed to apply dir-pwm state: %d\n", err);
 			pwm_disable(vibrator->pwm);
···
 	/* Sync up PWM state and ensure it is off. */
 	pwm_init_state(vibrator->pwm, &state);
 	state.enabled = false;
-	err = pwm_apply_state(vibrator->pwm, &state);
+	err = pwm_apply_might_sleep(vibrator->pwm, &state);
 	if (err) {
 		dev_err(&pdev->dev, "failed to apply initial PWM state: %d\n",
 			err);
···
 		/* Sync up PWM state and ensure it is off. */
 		pwm_init_state(vibrator->pwm_dir, &state);
 		state.enabled = false;
-		err = pwm_apply_state(vibrator->pwm_dir, &state);
+		err = pwm_apply_might_sleep(vibrator->pwm_dir, &state);
 		if (err) {
 			dev_err(&pdev->dev, "failed to apply initial PWM state: %d\n",
 				err);

drivers/leds/leds-pwm.c

···
 
 	led_dat->pwmstate.duty_cycle = duty;
 	led_dat->pwmstate.enabled = true;
-	return pwm_apply_state(led_dat->pwm, &led_dat->pwmstate);
+	return pwm_apply_might_sleep(led_dat->pwm, &led_dat->pwmstate);
 }
 
 __attribute__((nonnull))

drivers/leds/rgb/leds-pwm-multicolor.c

···
 
 		priv->leds[i].state.duty_cycle = duty;
 		priv->leds[i].state.enabled = duty > 0;
-		ret = pwm_apply_state(priv->leds[i].pwm,
-				      &priv->leds[i].state);
+		ret = pwm_apply_might_sleep(priv->leds[i].pwm,
+					    &priv->leds[i].state);
 		if (ret)
 			break;
 	}

drivers/media/rc/pwm-ir-tx.c

···
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/hrtimer.h>
+#include <linux/completion.h>
 #include <media/rc-core.h>
 
 #define DRIVER_NAME	"pwm-ir-tx"
···
 
 struct pwm_ir {
 	struct pwm_device *pwm;
-	unsigned int carrier;
-	unsigned int duty_cycle;
+	struct hrtimer timer;
+	struct completion tx_done;
+	struct pwm_state *state;
+	u32 carrier;
+	u32 duty_cycle;
+	const unsigned int *txbuf;
+	unsigned int txbuf_len;
+	unsigned int txbuf_index;
 };
 
 static const struct of_device_id pwm_ir_of_match[] = {
···
 	return 0;
 }
 
-static int pwm_ir_tx(struct rc_dev *dev, unsigned int *txbuf,
-		     unsigned int count)
+static int pwm_ir_tx_sleep(struct rc_dev *dev, unsigned int *txbuf,
+			   unsigned int count)
 {
 	struct pwm_ir *pwm_ir = dev->priv;
 	struct pwm_device *pwm = pwm_ir->pwm;
···
 
 	for (i = 0; i < count; i++) {
 		state.enabled = !(i % 2);
-		pwm_apply_state(pwm, &state);
+		pwm_apply_might_sleep(pwm, &state);
 
 		edge = ktime_add_us(edge, txbuf[i]);
 		delta = ktime_us_delta(edge, ktime_get());
···
 	}
 
 	state.enabled = false;
-	pwm_apply_state(pwm, &state);
+	pwm_apply_might_sleep(pwm, &state);
 
 	return count;
+}
+
+static int pwm_ir_tx_atomic(struct rc_dev *dev, unsigned int *txbuf,
+			    unsigned int count)
+{
+	struct pwm_ir *pwm_ir = dev->priv;
+	struct pwm_device *pwm = pwm_ir->pwm;
+	struct pwm_state state;
+
+	pwm_init_state(pwm, &state);
+
+	state.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, pwm_ir->carrier);
+	pwm_set_relative_duty_cycle(&state, pwm_ir->duty_cycle, 100);
+
+	pwm_ir->txbuf = txbuf;
+	pwm_ir->txbuf_len = count;
+	pwm_ir->txbuf_index = 0;
+	pwm_ir->state = &state;
+
+	hrtimer_start(&pwm_ir->timer, 0, HRTIMER_MODE_REL);
+
+	wait_for_completion(&pwm_ir->tx_done);
+
+	return count;
+}
+
+static enum hrtimer_restart pwm_ir_timer(struct hrtimer *timer)
+{
+	struct pwm_ir *pwm_ir = container_of(timer, struct pwm_ir, timer);
+	ktime_t now;
+
+	/*
+	 * If we happen to hit an odd latency spike, loop through the
+	 * pulses until we catch up.
+	 */
+	do {
+		u64 ns;
+
+		pwm_ir->state->enabled = !(pwm_ir->txbuf_index % 2);
+		pwm_apply_atomic(pwm_ir->pwm, pwm_ir->state);
+
+		if (pwm_ir->txbuf_index >= pwm_ir->txbuf_len) {
+			complete(&pwm_ir->tx_done);
+
+			return HRTIMER_NORESTART;
+		}
+
+		ns = US_TO_NS(pwm_ir->txbuf[pwm_ir->txbuf_index]);
+		hrtimer_add_expires_ns(timer, ns);
+
+		pwm_ir->txbuf_index++;
+
+		now = timer->base->get_time();
+	} while (hrtimer_get_expires_tv64(timer) < now);
+
+	return HRTIMER_RESTART;
 }
 
 static int pwm_ir_probe(struct platform_device *pdev)
···
 	if (!rcdev)
 		return -ENOMEM;
 
+	if (pwm_might_sleep(pwm_ir->pwm)) {
+		dev_info(&pdev->dev, "TX will not be accurate as PWM device might sleep\n");
+		rcdev->tx_ir = pwm_ir_tx_sleep;
+	} else {
+		init_completion(&pwm_ir->tx_done);
+		hrtimer_init(&pwm_ir->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		pwm_ir->timer.function = pwm_ir_timer;
+		rcdev->tx_ir = pwm_ir_tx_atomic;
+	}
+
 	rcdev->priv = pwm_ir;
 	rcdev->driver_name = DRIVER_NAME;
 	rcdev->device_name = DEVICE_NAME;
-	rcdev->tx_ir = pwm_ir_tx;
 	rcdev->s_tx_duty_cycle = pwm_ir_set_duty_cycle;
 	rcdev->s_tx_carrier = pwm_ir_set_carrier;
 

drivers/platform/x86/lenovo-yogabook.c

···
 		.enabled = level,
 	};
 
-	pwm_apply_state(data->kbd_bl_pwm, &state);
+	pwm_apply_might_sleep(data->kbd_bl_pwm, &state);
 	gpiod_set_value(data->kbd_bl_led_enable, level ? 1 : 0);
 	return 0;
 }

drivers/pwm/core.c

···
 
 #include <linux/acpi.h>
 #include <linux/module.h>
+#include <linux/idr.h>
 #include <linux/of.h>
 #include <linux/pwm.h>
 #include <linux/list.h>
···
 #define CREATE_TRACE_POINTS
 #include <trace/events/pwm.h>
 
-#define MAX_PWMS 1024
-
 static DEFINE_MUTEX(pwm_lookup_lock);
 static LIST_HEAD(pwm_lookup_list);
 
-/* protects access to pwm_chips and allocated_pwms */
+/* protects access to pwm_chips */
 static DEFINE_MUTEX(pwm_lock);
 
-static LIST_HEAD(pwm_chips);
-static DECLARE_BITMAP(allocated_pwms, MAX_PWMS);
-
-/* Called with pwm_lock held */
-static int alloc_pwms(unsigned int count)
-{
-	unsigned int start;
-
-	start = bitmap_find_next_zero_area(allocated_pwms, MAX_PWMS, 0,
-					   count, 0);
-
-	if (start + count > MAX_PWMS)
-		return -ENOSPC;
-
-	bitmap_set(allocated_pwms, start, count);
-
-	return start;
-}
-
-/* Called with pwm_lock held */
-static void free_pwms(struct pwm_chip *chip)
-{
-	bitmap_clear(allocated_pwms, chip->base, chip->npwm);
-
-	kfree(chip->pwms);
-	chip->pwms = NULL;
-}
+static DEFINE_IDR(pwm_chips);
 
 static struct pwm_chip *pwmchip_find_by_name(const char *name)
 {
 	struct pwm_chip *chip;
+	unsigned long id, tmp;
 
 	if (!name)
 		return NULL;
 
 	mutex_lock(&pwm_lock);
 
-	list_for_each_entry(chip, &pwm_chips, list) {
+	idr_for_each_entry_ul(&pwm_chips, chip, tmp, id) {
 		const char *chip_name = dev_name(chip->dev);
 
 		if (chip_name && strcmp(chip_name, name) == 0) {
···
 static int pwm_device_request(struct pwm_device *pwm, const char *label)
 {
 	int err;
+	struct pwm_chip *chip = pwm->chip;
+	const struct pwm_ops *ops = chip->ops;
 
 	if (test_bit(PWMF_REQUESTED, &pwm->flags))
 		return -EBUSY;
 
-	if (!try_module_get(pwm->chip->owner))
+	if (!try_module_get(chip->owner))
 		return -ENODEV;
 
-	if (pwm->chip->ops->request) {
-		err = pwm->chip->ops->request(pwm->chip, pwm);
+	if (ops->request) {
+		err = ops->request(chip, pwm);
 		if (err) {
-			module_put(pwm->chip->owner);
+			module_put(chip->owner);
 			return err;
 		}
 	}
 
-	if (pwm->chip->ops->get_state) {
+	if (ops->get_state) {
 		/*
 		 * Zero-initialize state because most drivers are unaware of
 		 * .usage_power. The other members of state are supposed to be
···
 		 */
 		struct pwm_state state = { 0, };
 
-		err = pwm->chip->ops->get_state(pwm->chip, pwm, &state);
+		err = ops->get_state(chip, pwm, &state);
 		trace_pwm_get(pwm, &state, err);
 
 		if (!err)
···
  */
 int __pwmchip_add(struct pwm_chip *chip, struct module *owner)
 {
-	struct pwm_device *pwm;
 	unsigned int i;
 	int ret;
 
···
 
 	chip->owner = owner;
 
-	chip->pwms = kcalloc(chip->npwm, sizeof(*pwm), GFP_KERNEL);
+	chip->pwms = kcalloc(chip->npwm, sizeof(*chip->pwms), GFP_KERNEL);
 	if (!chip->pwms)
 		return -ENOMEM;
 
 	mutex_lock(&pwm_lock);
 
-	ret = alloc_pwms(chip->npwm);
+	ret = idr_alloc(&pwm_chips, chip, 0, 0, GFP_KERNEL);
 	if (ret < 0) {
 		mutex_unlock(&pwm_lock);
 		kfree(chip->pwms);
 		return ret;
 	}
 
-	chip->base = ret;
+	chip->id = ret;
 
 	for (i = 0; i < chip->npwm; i++) {
-		pwm = &chip->pwms[i];
+		struct pwm_device *pwm = &chip->pwms[i];
 
 		pwm->chip = chip;
-		pwm->pwm = chip->base + i;
 		pwm->hwpwm = i;
 	}
-
-	list_add(&chip->list, &pwm_chips);
 
 	mutex_unlock(&pwm_lock);
 
···
 
 	mutex_lock(&pwm_lock);
 
-	list_del_init(&chip->list);
-
-	free_pwms(chip);
+	idr_remove(&pwm_chips, chip->id);
 
 	mutex_unlock(&pwm_lock);
+
+	kfree(chip->pwms);
 }
 EXPORT_SYMBOL_GPL(pwmchip_remove);
 
···
 }
 EXPORT_SYMBOL_GPL(pwm_request_from_chip);
 
-static void pwm_apply_state_debug(struct pwm_device *pwm,
-				  const struct pwm_state *state)
+static void pwm_apply_debug(struct pwm_device *pwm,
+			    const struct pwm_state *state)
 {
 	struct pwm_state *last = &pwm->last;
 	struct pwm_chip *chip = pwm->chip;
···
 }
 
 /**
- * pwm_apply_state() - atomically apply a new state to a PWM device
+ * __pwm_apply() - atomically apply a new state to a PWM device
  * @pwm: PWM device
  * @state: new state to apply
  */
-int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state)
+static int __pwm_apply(struct pwm_device *pwm, const struct pwm_state *state)
 {
 	struct pwm_chip *chip;
 	int err;
-
-	/*
-	 * Some lowlevel driver's implementations of .apply() make use of
-	 * mutexes, also with some drivers only returning when the new
-	 * configuration is active calling pwm_apply_state() from atomic context
-	 * is a bad idea. So make it explicit that calling this function might
-	 * sleep.
-	 */
-	might_sleep();
 
 	if (!pwm || !state || !state->period ||
 	    state->duty_cycle > state->period)
···
 	 * only do this after pwm->state was applied as some
 	 * implementations of .get_state depend on this
 	 */
-	pwm_apply_state_debug(pwm, state);
+	pwm_apply_debug(pwm, state);
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(pwm_apply_state);
+
+/**
+ * pwm_apply_might_sleep() - atomically apply a new state to a PWM device
+ * Cannot be used in atomic context.
+ * @pwm: PWM device
+ * @state: new state to apply
+ */
+int pwm_apply_might_sleep(struct pwm_device *pwm, const struct pwm_state *state)
+{
+	int err;
+
+	/*
+	 * Some lowlevel driver's implementations of .apply() make use of
+	 * mutexes, also with some drivers only returning when the new
+	 * configuration is active calling pwm_apply_might_sleep() from atomic context
+	 * is a bad idea. So make it explicit that calling this function might
+	 * sleep.
+	 */
+	might_sleep();
+
+	if (IS_ENABLED(CONFIG_PWM_DEBUG) && pwm->chip->atomic) {
+		/*
+		 * Catch any drivers that have been marked as atomic but
+		 * that will sleep anyway.
+		 */
+		non_block_start();
+		err = __pwm_apply(pwm, state);
+		non_block_end();
+	} else {
+		err = __pwm_apply(pwm, state);
+	}
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(pwm_apply_might_sleep);
+
+/**
+ * pwm_apply_atomic() - apply a new state to a PWM device from atomic context
+ * Not all PWM devices support this function, check with pwm_might_sleep().
+ * @pwm: PWM device
+ * @state: new state to apply
+ */
+int pwm_apply_atomic(struct pwm_device *pwm, const struct pwm_state *state)
+{
+	WARN_ONCE(!pwm->chip->atomic,
+		  "sleeping PWM driver used in atomic context\n");
+
+	return __pwm_apply(pwm, state);
+}
+EXPORT_SYMBOL_GPL(pwm_apply_atomic);
 
 /**
  * pwm_capture() - capture and report a PWM signal
···
 		state.period = pargs.period;
 		state.polarity = pargs.polarity;
 
-		return pwm_apply_state(pwm, &state);
+		return pwm_apply_might_sleep(pwm, &state);
 	}
 
 	/*
···
 		state.duty_cycle = state.period - state.duty_cycle;
 	}
 
-	return pwm_apply_state(pwm, &state);
+	return pwm_apply_might_sleep(pwm, &state);
 }
 EXPORT_SYMBOL_GPL(pwm_adjust_config);
 
 static struct pwm_chip *fwnode_to_pwmchip(struct fwnode_handle *fwnode)
 {
 	struct pwm_chip *chip;
+	unsigned long id, tmp;
 
 	mutex_lock(&pwm_lock);
 
-	list_for_each_entry(chip, &pwm_chips, list)
+	idr_for_each_entry_ul(&pwm_chips, chip, tmp, id)
 		if (chip->dev && device_match_fwnode(chip->dev, fwnode)) {
 			mutex_unlock(&pwm_lock);
 			return chip;
···
 
 static void *pwm_seq_start(struct seq_file *s, loff_t *pos)
 {
+	unsigned long id = *pos;
+	void *ret;
+
 	mutex_lock(&pwm_lock);
 	s->private = "";
 
-	return seq_list_start(&pwm_chips, *pos);
+	ret = idr_get_next_ul(&pwm_chips, &id);
+	*pos = id;
+	return ret;
 }
 
 static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos)
 {
+	unsigned long id = *pos + 1;
+	void *ret;
+
 	s->private = "\n";
 
-	return seq_list_next(v, &pwm_chips, pos);
+	ret = idr_get_next_ul(&pwm_chips, &id);
+	*pos = id;
+	return ret;
 }
 
 static void pwm_seq_stop(struct seq_file *s, void *v)
···
 
 static int pwm_seq_show(struct seq_file *s, void *v)
 {
-	struct pwm_chip *chip = list_entry(v, struct pwm_chip, list);
+	struct pwm_chip *chip = v;
 
-	seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private,
+	seq_printf(s, "%s%d: %s/%s, %d PWM device%s\n",
+		   (char *)s->private, chip->id,
 		   chip->dev->bus ? chip->dev->bus->name : "no-bus",
 		   dev_name(chip->dev), chip->npwm,
 		   (chip->npwm != 1) ? "s" : "");

drivers/pwm/pwm-atmel-hlcdc.c

···
 	.div1_clk_erratum = true,
 };
 
-#ifdef CONFIG_PM_SLEEP
 static int atmel_hlcdc_pwm_suspend(struct device *dev)
 {
 	struct atmel_hlcdc_pwm *atmel = dev_get_drvdata(dev);
···
 	return atmel_hlcdc_pwm_apply(&atmel->chip, &atmel->chip.pwms[0],
 				     &state);
 }
-#endif
 
-static SIMPLE_DEV_PM_OPS(atmel_hlcdc_pwm_pm_ops,
-			 atmel_hlcdc_pwm_suspend, atmel_hlcdc_pwm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(atmel_hlcdc_pwm_pm_ops,
+				atmel_hlcdc_pwm_suspend, atmel_hlcdc_pwm_resume);
 
 static const struct of_device_id atmel_hlcdc_dt_ids[] = {
 	{
···
 	.driver = {
 		.name = "atmel-hlcdc-pwm",
 		.of_match_table = atmel_hlcdc_pwm_dt_ids,
-		.pm = &atmel_hlcdc_pwm_pm_ops,
+		.pm = pm_ptr(&atmel_hlcdc_pwm_pm_ops),
 	},
 	.probe = atmel_hlcdc_pwm_probe,
 	.remove_new = atmel_hlcdc_pwm_remove,

drivers/pwm/pwm-atmel-tcb.c

···
 };
 MODULE_DEVICE_TABLE(of, atmel_tcb_pwm_dt_ids);
 
-#ifdef CONFIG_PM_SLEEP
 static int atmel_tcb_pwm_suspend(struct device *dev)
 {
 	struct atmel_tcb_pwm_chip *tcbpwm = dev_get_drvdata(dev);
···
 
 	return 0;
 }
-#endif
 
-static SIMPLE_DEV_PM_OPS(atmel_tcb_pwm_pm_ops, atmel_tcb_pwm_suspend,
-			 atmel_tcb_pwm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(atmel_tcb_pwm_pm_ops, atmel_tcb_pwm_suspend,
+				atmel_tcb_pwm_resume);
 
 static struct platform_driver atmel_tcb_pwm_driver = {
 	.driver = {
 		.name = "atmel-tcb-pwm",
 		.of_match_table = atmel_tcb_pwm_dt_ids,
-		.pm = &atmel_tcb_pwm_pm_ops,
+		.pm = pm_ptr(&atmel_tcb_pwm_pm_ops),
 	},
 	.probe = atmel_tcb_pwm_probe,
 	.remove_new = atmel_tcb_pwm_remove,

drivers/pwm/pwm-bcm-kona.c

···
 			return err;
 	}
 
-	err = kona_pwmc_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = kona_pwmc_config(chip, pwm, state->duty_cycle, state->period);
 	if (err && !pwm->state.enabled)
 		clk_disable_unprepare(kp->clk);
 

drivers/pwm/pwm-bcm2835.c

···
 	struct device *dev;
 	void __iomem *base;
 	struct clk *clk;
+	unsigned long rate;
 };
 
 static inline struct bcm2835_pwm *to_bcm2835_pwm(struct pwm_chip *chip)
···
 {
 
 	struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
-	unsigned long rate = clk_get_rate(pc->clk);
 	unsigned long long period_cycles;
 	u64 max_period;
 
 	u32 val;
-
-	if (!rate) {
-		dev_err(pc->dev, "failed to get clock rate\n");
-		return -EINVAL;
-	}
 
 	/*
 	 * period_cycles must be a 32 bit value, so period * rate / NSEC_PER_SEC
···
 	 * <=> period < ((U32_MAX * NSEC_PER_SEC + NSEC_PER_SEC/2) / rate
 	 * <=> period <= ceil((U32_MAX * NSEC_PER_SEC + NSEC_PER_SEC/2) / rate) - 1
 	 */
-	max_period = DIV_ROUND_UP_ULL((u64)U32_MAX * NSEC_PER_SEC + NSEC_PER_SEC / 2, rate) - 1;
+	max_period = DIV_ROUND_UP_ULL((u64)U32_MAX * NSEC_PER_SEC + NSEC_PER_SEC / 2, pc->rate) - 1;
 
 	if (state->period > max_period)
 		return -EINVAL;
 
 	/* set period */
-	period_cycles = DIV_ROUND_CLOSEST_ULL(state->period * rate, NSEC_PER_SEC);
+	period_cycles = DIV_ROUND_CLOSEST_ULL(state->period * pc->rate, NSEC_PER_SEC);
 
 	/* don't accept a period that is too small */
 	if (period_cycles < PERIOD_MIN)
···
 	writel(period_cycles, pc->base + PERIOD(pwm->hwpwm));
 
 	/* set duty cycle */
-	val = DIV_ROUND_CLOSEST_ULL(state->duty_cycle * rate, NSEC_PER_SEC);
+	val = DIV_ROUND_CLOSEST_ULL(state->duty_cycle * pc->rate, NSEC_PER_SEC);
 	writel(val, pc->base + DUTY(pwm->hwpwm));
 
 	/* set polarity */
···
 	.apply = bcm2835_pwm_apply,
 };
 
+static void devm_clk_rate_exclusive_put(void *data)
+{
+	struct clk *clk = data;
+
+	clk_rate_exclusive_put(clk);
+}
+
 static int bcm2835_pwm_probe(struct platform_device *pdev)
 {
 	struct bcm2835_pwm *pc;
···
 		return dev_err_probe(&pdev->dev, PTR_ERR(pc->clk),
 				     "clock not found\n");
 
+	ret = clk_rate_exclusive_get(pc->clk);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret,
+				     "fail to get exclusive rate\n");
+
+	ret = devm_add_action_or_reset(&pdev->dev, devm_clk_rate_exclusive_put,
+				       pc->clk);
+	if (ret) {
+		clk_rate_exclusive_put(pc->clk);
+		return ret;
+	}
+
+	pc->rate = clk_get_rate(pc->clk);
+	if (!pc->rate)
+		return dev_err_probe(&pdev->dev, -EINVAL,
+				     "failed to get clock rate\n");
+
 	pc->chip.dev = &pdev->dev;
 	pc->chip.ops = &bcm2835_pwm_ops;
+	pc->chip.atomic = true;
 	pc->chip.npwm = 2;
 
 	platform_set_drvdata(pdev, pc);

drivers/pwm/pwm-berlin.c

···
 	return 0;
 }
 
-#ifdef CONFIG_PM_SLEEP
 static int berlin_pwm_suspend(struct device *dev)
 {
 	struct berlin_pwm_chip *bpc = dev_get_drvdata(dev);
···
 
 	return 0;
 }
-#endif
 
-static SIMPLE_DEV_PM_OPS(berlin_pwm_pm_ops, berlin_pwm_suspend,
-			 berlin_pwm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(berlin_pwm_pm_ops, berlin_pwm_suspend,
+				berlin_pwm_resume);
 
 static struct platform_driver berlin_pwm_driver = {
 	.probe = berlin_pwm_probe,
 	.driver = {
 		.name = "berlin-pwm",
 		.of_match_table = berlin_pwm_match,
-		.pm = &berlin_pwm_pm_ops,
+		.pm = pm_ptr(&berlin_pwm_pm_ops),
 	},
 };
 module_platform_driver(berlin_pwm_driver);

drivers/pwm/pwm-brcmstb.c

···
 	return 0;
 }
 
-#ifdef CONFIG_PM_SLEEP
 static int brcmstb_pwm_suspend(struct device *dev)
 {
 	struct brcmstb_pwm *p = dev_get_drvdata(dev);
···
 
 	return clk_prepare_enable(p->clk);
 }
-#endif
 
-static SIMPLE_DEV_PM_OPS(brcmstb_pwm_pm_ops, brcmstb_pwm_suspend,
-			 brcmstb_pwm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(brcmstb_pwm_pm_ops, brcmstb_pwm_suspend,
+				brcmstb_pwm_resume);
 
 static struct platform_driver brcmstb_pwm_driver = {
 	.probe = brcmstb_pwm_probe,
 	.driver = {
 		.name = "pwm-brcmstb",
 		.of_match_table = brcmstb_pwm_of_match,
-		.pm = &brcmstb_pwm_pm_ops,
+		.pm = pm_ptr(&brcmstb_pwm_pm_ops),
 	},
 };
 module_platform_driver(brcmstb_pwm_driver);

drivers/pwm/pwm-crc.c

···
 
 static int crystalcove_pwm_probe(struct platform_device *pdev)
 {
-	struct crystalcove_pwm *pwm;
+	struct crystalcove_pwm *crc_pwm;
 	struct device *dev = pdev->dev.parent;
 	struct intel_soc_pmic *pmic = dev_get_drvdata(dev);
 
-	pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
-	if (!pwm)
+	crc_pwm = devm_kzalloc(&pdev->dev, sizeof(*crc_pwm), GFP_KERNEL);
+	if (!crc_pwm)
 		return -ENOMEM;
 
-	pwm->chip.dev = &pdev->dev;
-	pwm->chip.ops = &crc_pwm_ops;
-	pwm->chip.npwm = 1;
+	crc_pwm->chip.dev = &pdev->dev;
+	crc_pwm->chip.ops = &crc_pwm_ops;
+	crc_pwm->chip.npwm = 1;
 
 	/* get the PMIC regmap */
-	pwm->regmap = pmic->regmap;
+	crc_pwm->regmap = pmic->regmap;
 
-	return devm_pwmchip_add(&pdev->dev, &pwm->chip);
+	return devm_pwmchip_add(&pdev->dev, &crc_pwm->chip);
 }
 
 static struct platform_driver crystalcove_pwm_driver = {

drivers/pwm/pwm-cros-ec.c

···
 /**
  * struct cros_ec_pwm_device - Driver data for EC PWM
  *
- * @dev: Device node
  * @ec: Pointer to EC device
  * @chip: PWM controller chip
  * @use_pwm_type: Use PWM types instead of generic channels
  * @channel: array with per-channel data
  */
 struct cros_ec_pwm_device {
-	struct device *dev;
 	struct cros_ec_device *ec;
 	struct pwm_chip chip;
 	bool use_pwm_type;

drivers/pwm/pwm-dwc.c

···
 	pm_runtime_get_noresume(&pci->dev);
 }
 
-#ifdef CONFIG_PM_SLEEP
 static int dwc_pwm_suspend(struct device *dev)
 {
 	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
···
 
 	return 0;
 }
-#endif
 
-static SIMPLE_DEV_PM_OPS(dwc_pwm_pm_ops, dwc_pwm_suspend, dwc_pwm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(dwc_pwm_pm_ops, dwc_pwm_suspend, dwc_pwm_resume);
 
 static const struct pci_device_id dwc_pwm_id_table[] = {
 	{ PCI_VDEVICE(INTEL, 0x4bb7) }, /* Elkhart Lake */
···
 	.remove = dwc_pwm_remove,
 	.id_table = dwc_pwm_id_table,
 	.driver = {
-		.pm = &dwc_pwm_pm_ops,
+		.pm = pm_ptr(&dwc_pwm_pm_ops),
 	},
 };
 

drivers/pwm/pwm-img.c

···
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
+#include <linux/property.h>
 #include <linux/pwm.h>
 #include <linux/regmap.h>
 #include <linux/slab.h>
···
 		return 0;
 	}
 
-	err = img_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = img_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 
···
 	u64 val;
 	unsigned long clk_rate;
 	struct img_pwm_chip *imgchip;
-	const struct of_device_id *of_dev_id;
 
 	imgchip = devm_kzalloc(&pdev->dev, sizeof(*imgchip), GFP_KERNEL);
 	if (!imgchip)
···
 	if (IS_ERR(imgchip->base))
 		return PTR_ERR(imgchip->base);
 
-	of_dev_id = of_match_device(img_pwm_of_match, &pdev->dev);
-	if (!of_dev_id)
-		return -ENODEV;
-	imgchip->data = of_dev_id->data;
+	imgchip->data = device_get_match_data(&pdev->dev);
 
 	imgchip->periph_regs = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 							       "img,cr-periph");

drivers/pwm/pwm-imx-tpm.c

···
 	return 0;
 }
 
-static int __maybe_unused pwm_imx_tpm_suspend(struct device *dev)
+static int pwm_imx_tpm_suspend(struct device *dev)
 {
 	struct imx_tpm_pwm_chip *tpm = dev_get_drvdata(dev);
 
···
 	return 0;
 }
 
-static int __maybe_unused pwm_imx_tpm_resume(struct device *dev)
+static int pwm_imx_tpm_resume(struct device *dev)
 {
 	struct imx_tpm_pwm_chip *tpm = dev_get_drvdata(dev);
 	int ret = 0;
···
 	return ret;
 }
 
-static SIMPLE_DEV_PM_OPS(imx_tpm_pwm_pm,
-			 pwm_imx_tpm_suspend, pwm_imx_tpm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(imx_tpm_pwm_pm,
+				pwm_imx_tpm_suspend, pwm_imx_tpm_resume);
 
 static const struct of_device_id imx_tpm_pwm_dt_ids[] = {
 	{ .compatible = "fsl,imx7ulp-pwm", },
···
 	.driver = {
 		.name = "imx7ulp-tpm-pwm",
 		.of_match_table = imx_tpm_pwm_dt_ids,
-		.pm = &imx_tpm_pwm_pm,
+		.pm = pm_ptr(&imx_tpm_pwm_pm),
 	},
 	.probe	= pwm_imx_tpm_probe,
 };

drivers/pwm/pwm-jz4740.c

···
 static int jz4740_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
 			    const struct pwm_state *state)
 {
-	struct jz4740_pwm_chip *jz = to_jz4740(pwm->chip);
+	struct jz4740_pwm_chip *jz = to_jz4740(chip);
 	unsigned long long tmp = 0xffffull * NSEC_PER_SEC;
 	struct clk *clk = jz->clk[pwm->hwpwm];
 	unsigned long period, duty;
···
 	 */
 	rate = clk_round_rate(clk, tmp);
 	if (rate < 0) {
-		dev_err(chip->dev, "Unable to round rate: %ld", rate);
+		dev_err(chip->dev, "Unable to round rate: %ld\n", rate);
 		return rate;
 	}
 
···
 
 	err = clk_set_rate(clk, rate);
 	if (err) {
-		dev_err(chip->dev, "Unable to set rate: %d", err);
+		dev_err(chip->dev, "Unable to set rate: %d\n", err);
 		return err;
 	}
 

drivers/pwm/pwm-lpc18xx-sct.c

···
 			      int duty_ns, int period_ns)
 {
 	struct lpc18xx_pwm_chip *lpc18xx_pwm = to_lpc18xx_pwm_chip(chip);
-	int requested_events, i;
+	int requested_events;
 
 	if (period_ns < lpc18xx_pwm->min_period_ns ||
 	    period_ns > lpc18xx_pwm->max_period_ns) {
···
 	if ((requested_events <= 2 && lpc18xx_pwm->period_ns != period_ns) ||
 	    !lpc18xx_pwm->period_ns) {
 		lpc18xx_pwm->period_ns = period_ns;
-		for (i = 0; i < chip->npwm; i++)
-			pwm_set_period(&chip->pwms[i], period_ns);
 		lpc18xx_pwm_config_period(chip, period_ns);
 	}
 
···
 		return 0;
 	}
 
-	err = lpc18xx_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = lpc18xx_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 

drivers/pwm/pwm-lpc32xx.c

···
 		return 0;
 	}
 
-	err = lpc32xx_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = lpc32xx_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 

drivers/pwm/pwm-mediatek.c

···
 		return 0;
 	}
 
-	err = pwm_mediatek_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = pwm_mediatek_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 

drivers/pwm/pwm-meson.c

···
 		channel->mux.hw.init = &init;
 
 		err = devm_clk_hw_register(dev, &channel->mux.hw);
-		if (err) {
-			dev_err(dev, "failed to register %s: %d\n", name, err);
-			return err;
-		}
+		if (err)
+			return dev_err_probe(dev, err,
+					     "failed to register %s\n", name);
 
 		snprintf(name, sizeof(name), "%s#div%u", dev_name(dev), i);
 
···
 		channel->div.lock = &meson->lock;
 
 		err = devm_clk_hw_register(dev, &channel->div.hw);
-		if (err) {
-			dev_err(dev, "failed to register %s: %d\n", name, err);
-			return err;
-		}
+		if (err)
+			return dev_err_probe(dev, err,
+					     "failed to register %s\n", name);
 
 		snprintf(name, sizeof(name), "%s#gate%u", dev_name(dev), i);
 
···
 		channel->gate.lock = &meson->lock;
 
 		err = devm_clk_hw_register(dev, &channel->gate.hw);
-		if (err) {
-			dev_err(dev, "failed to register %s: %d\n", name, err);
-			return err;
-		}
+		if (err)
+			return dev_err_probe(dev, err, "failed to register %s\n", name);
 
 		channel->clk = devm_clk_hw_get_clk(dev, &channel->gate.hw, NULL);
-		if (IS_ERR(channel->clk)) {
-			err = PTR_ERR(channel->clk);
-			dev_err(dev, "failed to register %s: %d\n", name, err);
-			return err;
-		}
+		if (IS_ERR(channel->clk))
+			return dev_err_probe(dev, PTR_ERR(channel->clk),
+					     "failed to register %s\n", name);
 	}
 
 	return 0;
···
 		return err;
 
 	err = devm_pwmchip_add(&pdev->dev, &meson->chip);
-	if (err < 0) {
-		dev_err(&pdev->dev, "failed to register PWM chip: %d\n", err);
-		return err;
-	}
+	if (err < 0)
+		return dev_err_probe(&pdev->dev, err,
+				     "failed to register PWM chip\n");
 
 	return 0;
 }

drivers/pwm/pwm-omap-dmtimer.c

···
 #include <linux/err.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
-#include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
 #include <clocksource/timer-ti-dm.h>
···
  * struct pwm_omap_dmtimer_chip - Structure representing a pwm chip
  *				  corresponding to omap dmtimer.
  * @chip:		PWM chip structure representing PWM controller
- * @mutex:		Mutex to protect pwm apply state
  * @dm_timer:		Pointer to omap dm timer.
  * @pdata:		Pointer to omap dm timer ops.
  * @dm_timer_pdev:	Pointer to omap dm timer platform device
···
 struct pwm_omap_dmtimer_chip {
 	struct pwm_chip chip;
 	/* Mutex to protect pwm apply state */
-	struct mutex mutex;
 	struct omap_dm_timer *dm_timer;
 	const struct omap_dm_timer_ops *pdata;
 	struct platform_device *dm_timer_pdev;
···
 				  const struct pwm_state *state)
 {
 	struct pwm_omap_dmtimer_chip *omap = to_pwm_omap_dmtimer_chip(chip);
-	int ret = 0;
-
-	mutex_lock(&omap->mutex);
+	int ret;
 
 	if (pwm_omap_dmtimer_is_enabled(omap) && !state->enabled) {
 		omap->pdata->stop(omap->dm_timer);
-		goto unlock_mutex;
+		return 0;
 	}
 
 	if (pwm_omap_dmtimer_polarity(omap) != state->polarity)
···
 	ret = pwm_omap_dmtimer_config(chip, pwm, state->duty_cycle,
 				      state->period);
 	if (ret)
-		goto unlock_mutex;
+		return ret;
 
 	if (!pwm_omap_dmtimer_is_enabled(omap) && state->enabled) {
 		omap->pdata->set_pwm(omap->dm_timer,
···
 		pwm_omap_dmtimer_start(omap);
 	}
 
-unlock_mutex:
-	mutex_unlock(&omap->mutex);
-
-	return ret;
+	return 0;
 }
 
 static const struct pwm_ops pwm_omap_dmtimer_ops = {
···
 	omap->chip.ops = &pwm_omap_dmtimer_ops;
 	omap->chip.npwm = 1;
 
-	mutex_init(&omap->mutex);
-
 	ret = pwmchip_add(&omap->chip);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "failed to register PWM\n");
···
 	omap->pdata->free(omap->dm_timer);
 
 	put_device(&omap->dm_timer_pdev->dev);
-
-	mutex_destroy(&omap->mutex);
 }
 
 static const struct of_device_id pwm_omap_dmtimer_of_match[] = {

drivers/pwm/pwm-renesas-tpu.c

···
 #include <linux/init.h>
 #include <linux/ioport.h>
 #include <linux/module.h>
-#include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
···
 		return 0;
 	}
 
-	err = tpu_pwm_config(pwm->chip, pwm,
+	err = tpu_pwm_config(chip, pwm,
 			     state->duty_cycle, state->period, enabled);
 	if (err)
 		return err;

drivers/pwm/pwm-rockchip.c

···
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_device.h>
 #include <linux/platform_device.h>
+#include <linux/property.h>
 #include <linux/pwm.h>
 #include <linux/time.h>
 
···
 
 static int rockchip_pwm_probe(struct platform_device *pdev)
 {
-	const struct of_device_id *id;
 	struct rockchip_pwm_chip *pc;
 	u32 enable_conf, ctrl;
 	bool enabled;
 	int ret, count;
-
-	id = of_match_device(rockchip_pwm_dt_ids, &pdev->dev);
-	if (!id)
-		return -EINVAL;
 
 	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
 	if (!pc)
···
 
 	platform_set_drvdata(pdev, pc);
 
-	pc->data = id->data;
+	pc->data = device_get_match_data(&pdev->dev);
 	pc->chip.dev = &pdev->dev;
 	pc->chip.ops = &rockchip_pwm_ops;
 	pc->chip.npwm = 1;

drivers/pwm/pwm-samsung.c

···
 	clk_disable_unprepare(our_chip->base_clk);
 }
 
-#ifdef CONFIG_PM_SLEEP
 static int pwm_samsung_resume(struct device *dev)
 {
 	struct samsung_pwm_chip *our_chip = dev_get_drvdata(dev);
···
 
 	return 0;
 }
-#endif
 
-static SIMPLE_DEV_PM_OPS(pwm_samsung_pm_ops, NULL, pwm_samsung_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(pwm_samsung_pm_ops, NULL, pwm_samsung_resume);
 
 static struct platform_driver pwm_samsung_driver = {
 	.driver		= {
 		.name	= "samsung-pwm",
-		.pm	= &pwm_samsung_pm_ops,
+		.pm	= pm_ptr(&pwm_samsung_pm_ops),
 		.of_match_table = of_match_ptr(samsung_pwm_matches),
 	},
 	.probe		= pwm_samsung_probe,

drivers/pwm/pwm-sti.c

···
 		return 0;
 	}
 
-	err = sti_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = sti_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 

drivers/pwm/pwm-stm32-lp.c

···
 	return 0;
 }
 
-static int __maybe_unused stm32_pwm_lp_suspend(struct device *dev)
+static int stm32_pwm_lp_suspend(struct device *dev)
 {
 	struct stm32_pwm_lp *priv = dev_get_drvdata(dev);
 	struct pwm_state state;
···
 	return pinctrl_pm_select_sleep_state(dev);
 }
 
-static int __maybe_unused stm32_pwm_lp_resume(struct device *dev)
+static int stm32_pwm_lp_resume(struct device *dev)
 {
 	return pinctrl_pm_select_default_state(dev);
 }
 
-static SIMPLE_DEV_PM_OPS(stm32_pwm_lp_pm_ops, stm32_pwm_lp_suspend,
-			 stm32_pwm_lp_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(stm32_pwm_lp_pm_ops, stm32_pwm_lp_suspend,
+				stm32_pwm_lp_resume);
 
 static const struct of_device_id stm32_pwm_lp_of_match[] = {
 	{ .compatible = "st,stm32-pwm-lp", },
···
 	.driver	= {
 		.name = "stm32-pwm-lp",
 		.of_match_table = stm32_pwm_lp_of_match,
-		.pm = &stm32_pwm_lp_pm_ops,
+		.pm = pm_ptr(&stm32_pwm_lp_pm_ops),
 	},
 };
 module_platform_driver(stm32_pwm_lp_driver);

drivers/pwm/pwm-stm32.c

···
 	return ccer & TIM_CCER_CCXE;
 }
 
-static int write_ccrx(struct stm32_pwm *dev, int ch, u32 value)
-{
-	switch (ch) {
-	case 0:
-		return regmap_write(dev->regmap, TIM_CCR1, value);
-	case 1:
-		return regmap_write(dev->regmap, TIM_CCR2, value);
-	case 2:
-		return regmap_write(dev->regmap, TIM_CCR3, value);
-	case 3:
-		return regmap_write(dev->regmap, TIM_CCR4, value);
-	}
-	return -EINVAL;
-}
-
 #define TIM_CCER_CC12P (TIM_CCER_CC1P | TIM_CCER_CC2P)
 #define TIM_CCER_CC12E (TIM_CCER_CC1E | TIM_CCER_CC2E)
 #define TIM_CCER_CC34P (TIM_CCER_CC3P | TIM_CCER_CC4P)
···
 	return ret;
 }
 
-static int stm32_pwm_config(struct stm32_pwm *priv, int ch,
+static int stm32_pwm_config(struct stm32_pwm *priv, unsigned int ch,
 			    int duty_ns, int period_ns)
 {
 	unsigned long long prd, div, dty;
···
 	dty = prd * duty_ns;
 	do_div(dty, period_ns);
 
-	write_ccrx(priv, ch, dty);
+	regmap_write(priv->regmap, TIM_CCR1 + 4 * ch, dty);
 
 	/* Configure output mode */
 	shift = (ch & 0x1) * CCMR_CHANNEL_SHIFT;
···
 	return 0;
 }
 
-static int stm32_pwm_set_polarity(struct stm32_pwm *priv, int ch,
+static int stm32_pwm_set_polarity(struct stm32_pwm *priv, unsigned int ch,
 				  enum pwm_polarity polarity)
 {
 	u32 mask;
···
 	return 0;
 }
 
-static int stm32_pwm_enable(struct stm32_pwm *priv, int ch)
+static int stm32_pwm_enable(struct stm32_pwm *priv, unsigned int ch)
 {
 	u32 mask;
 	int ret;
···
 	return 0;
 }
 
-static void stm32_pwm_disable(struct stm32_pwm *priv, int ch)
+static void stm32_pwm_disable(struct stm32_pwm *priv, unsigned int ch)
 {
 	u32 mask;
 
···
 	return ret;
 }
 
+static int stm32_pwm_get_state(struct pwm_chip *chip,
+			       struct pwm_device *pwm, struct pwm_state *state)
+{
+	struct stm32_pwm *priv = to_stm32_pwm_dev(chip);
+	int ch = pwm->hwpwm;
+	unsigned long rate;
+	u32 ccer, psc, arr, ccr;
+	u64 dty, prd;
+	int ret;
+
+	mutex_lock(&priv->lock);
+
+	ret = regmap_read(priv->regmap, TIM_CCER, &ccer);
+	if (ret)
+		goto out;
+
+	state->enabled = ccer & (TIM_CCER_CC1E << (ch * 4));
+	state->polarity = (ccer & (TIM_CCER_CC1P << (ch * 4))) ?
+			  PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL;
+	ret = regmap_read(priv->regmap, TIM_PSC, &psc);
+	if (ret)
+		goto out;
+	ret = regmap_read(priv->regmap, TIM_ARR, &arr);
+	if (ret)
+		goto out;
+	ret = regmap_read(priv->regmap, TIM_CCR1 + 4 * ch, &ccr);
+	if (ret)
+		goto out;
+
+	rate = clk_get_rate(priv->clk);
+
+	prd = (u64)NSEC_PER_SEC * (psc + 1) * (arr + 1);
+	state->period = DIV_ROUND_UP_ULL(prd, rate);
+	dty = (u64)NSEC_PER_SEC * (psc + 1) * ccr;
+	state->duty_cycle = DIV_ROUND_UP_ULL(dty, rate);
+
+out:
+	mutex_unlock(&priv->lock);
+	return ret;
+}
+
 static const struct pwm_ops stm32pwm_ops = {
 	.apply = stm32_pwm_apply_locked,
+	.get_state = stm32_pwm_get_state,
 	.capture = IS_ENABLED(CONFIG_DMA_ENGINE) ? stm32_pwm_capture : NULL,
 };
 
···
 	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_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_clear_bits(priv->regmap, TIM_CCER, TIM_CCER_CCXE);
+	regmap_write(priv->regmap, TIM_CCER, ccer_backup);
 
-	if (ccer & TIM_CCER_CC1E)
-		npwm++;
+	*num_enabled = hweight32(ccer_backup & TIM_CCER_CCXE);
 
-	if (ccer & TIM_CCER_CC2E)
-		npwm++;
-
-	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)
···
 	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);
···
 
 	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 = devm_pwmchip_add(dev, &priv->chip);
 	if (ret < 0)
···
 	return 0;
 }
 
-static int __maybe_unused stm32_pwm_suspend(struct device *dev)
+static int stm32_pwm_suspend(struct device *dev)
 {
 	struct stm32_pwm *priv = dev_get_drvdata(dev);
 	unsigned int i;
···
 	return pinctrl_pm_select_sleep_state(dev);
 }
 
-static int __maybe_unused stm32_pwm_resume(struct device *dev)
+static int stm32_pwm_resume(struct device *dev)
 {
 	struct stm32_pwm *priv = dev_get_drvdata(dev);
 	int ret;
···
 	return stm32_pwm_apply_breakinputs(priv);
 }
 
-static SIMPLE_DEV_PM_OPS(stm32_pwm_pm_ops, stm32_pwm_suspend, stm32_pwm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(stm32_pwm_pm_ops, stm32_pwm_suspend, stm32_pwm_resume);
 
 static const struct of_device_id stm32_pwm_of_match[] = {
 	{ .compatible = "st,stm32-pwm",	},
···
 	.driver	= {
 		.name = "stm32-pwm",
 		.of_match_table = stm32_pwm_of_match,
-		.pm = &stm32_pwm_pm_ops,
+		.pm = pm_ptr(&stm32_pwm_pm_ops),
 	},
 };
 module_platform_driver(stm32_pwm_driver);

drivers/pwm/pwm-stmpe.c

···
 
 	ret = stmpe_reg_read(stmpe_pwm->stmpe, STMPE24XX_PWMCS);
 	if (ret < 0) {
-		dev_err(chip->dev, "error reading PWM#%u control\n",
+		dev_dbg(chip->dev, "error reading PWM#%u control\n",
 			pwm->hwpwm);
 		return ret;
 	}
···
 
 	ret = stmpe_reg_write(stmpe_pwm->stmpe, STMPE24XX_PWMCS, value);
 	if (ret) {
-		dev_err(chip->dev, "error writing PWM#%u control\n",
+		dev_dbg(chip->dev, "error writing PWM#%u control\n",
 			pwm->hwpwm);
 		return ret;
 	}
···
 
 	ret = stmpe_reg_read(stmpe_pwm->stmpe, STMPE24XX_PWMCS);
 	if (ret < 0) {
-		dev_err(chip->dev, "error reading PWM#%u control\n",
+		dev_dbg(chip->dev, "error reading PWM#%u control\n",
 			pwm->hwpwm);
 		return ret;
 	}
···
 
 	ret = stmpe_reg_write(stmpe_pwm->stmpe, STMPE24XX_PWMCS, value);
 	if (ret)
-		dev_err(chip->dev, "error writing PWM#%u control\n",
+		dev_dbg(chip->dev, "error writing PWM#%u control\n",
 			pwm->hwpwm);
 	return ret;
 }
···
 
 		ret = stmpe_reg_write(stmpe_pwm->stmpe, offset, value);
 		if (ret) {
-			dev_err(chip->dev, "error writing register %02x: %d\n",
+			dev_dbg(chip->dev, "error writing register %02x: %d\n",
 				offset, ret);
 			return ret;
 		}
···
 
 		ret = stmpe_reg_write(stmpe_pwm->stmpe, offset, value);
 		if (ret) {
-			dev_err(chip->dev, "error writing register %02x: %d\n",
+			dev_dbg(chip->dev, "error writing register %02x: %d\n",
 				offset, ret);
 			return ret;
 		}
···
 		return 0;
 	}
 
-	err = stmpe_24xx_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = stmpe_24xx_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 

drivers/pwm/pwm-tegra.c

···
 		return 0;
 	}
 
-	err = tegra_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = tegra_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 

drivers/pwm/pwm-tiecap.c

···
 	pm_runtime_disable(&pdev->dev);
 }
 
-#ifdef CONFIG_PM_SLEEP
 static void ecap_pwm_save_context(struct ecap_pwm_chip *pc)
 {
 	pm_runtime_get_sync(pc->chip.dev);
···
 	ecap_pwm_restore_context(pc);
 	return 0;
 }
-#endif
 
-static SIMPLE_DEV_PM_OPS(ecap_pwm_pm_ops, ecap_pwm_suspend, ecap_pwm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(ecap_pwm_pm_ops, ecap_pwm_suspend, ecap_pwm_resume);
 
 static struct platform_driver ecap_pwm_driver = {
 	.driver = {
 		.name = "ecap",
 		.of_match_table = ecap_of_match,
-		.pm = &ecap_pwm_pm_ops,
+		.pm = pm_ptr(&ecap_pwm_pm_ops),
 	},
 	.probe = ecap_pwm_probe,
 	.remove_new = ecap_pwm_remove,

drivers/pwm/pwm-tiehrpwm.c

···
 	pm_runtime_disable(&pdev->dev);
 }
 
-#ifdef CONFIG_PM_SLEEP
 static void ehrpwm_pwm_save_context(struct ehrpwm_pwm_chip *pc)
 {
 	pm_runtime_get_sync(pc->chip.dev);
···
 
 	return 0;
 }
-#endif
 
-static SIMPLE_DEV_PM_OPS(ehrpwm_pwm_pm_ops, ehrpwm_pwm_suspend,
-			 ehrpwm_pwm_resume);
+static DEFINE_SIMPLE_DEV_PM_OPS(ehrpwm_pwm_pm_ops, ehrpwm_pwm_suspend,
+				ehrpwm_pwm_resume);
 
 static struct platform_driver ehrpwm_pwm_driver = {
 	.driver = {
 		.name = "ehrpwm",
 		.of_match_table = ehrpwm_of_match,
-		.pm = &ehrpwm_pwm_pm_ops,
+		.pm = pm_ptr(&ehrpwm_pwm_pm_ops),
 	},
 	.probe = ehrpwm_pwm_probe,
 	.remove_new = ehrpwm_pwm_remove,

drivers/pwm/pwm-twl-led.c

···
 	 * We cannot skip calling ->config even if state->period ==
 	 * pwm->state.period && state->duty_cycle == pwm->state.duty_cycle
 	 * because we might have exited early in the last call to
-	 * pwm_apply_state because of !state->enabled and so the two values in
+	 * pwm_apply_might_sleep because of !state->enabled and so the two values in
 	 * pwm->state might not be configured in hardware.
 	 */
-	ret = twl4030_pwmled_config(pwm->chip, pwm,
+	ret = twl4030_pwmled_config(chip, pwm,
 				    state->duty_cycle, state->period);
 	if (ret)
 		return ret;
···
 		return 0;
 	}
 
-	err = twl6030_pwmled_config(pwm->chip, pwm,
+	err = twl6030_pwmled_config(chip, pwm,
 				    state->duty_cycle, state->period);
 	if (err)
 		return err;

drivers/pwm/pwm-twl.c

···
 		return 0;
 	}
 
-	err = twl_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = twl_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 
···
 		return 0;
 	}
 
-	err = twl_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = twl_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 

drivers/pwm/pwm-vt8500.c

···
 	 * We cannot skip calling ->config even if state->period ==
 	 * pwm->state.period && state->duty_cycle == pwm->state.duty_cycle
 	 * because we might have exited early in the last call to
-	 * pwm_apply_state because of !state->enabled and so the two values in
+	 * pwm_apply_might_sleep because of !state->enabled and so the two values in
 	 * pwm->state might not be configured in hardware.
 	 */
-	err = vt8500_pwm_config(pwm->chip, pwm, state->duty_cycle, state->period);
+	err = vt8500_pwm_config(chip, pwm, state->duty_cycle, state->period);
 	if (err)
 		return err;
 

drivers/pwm/sysfs.c

···
 	mutex_lock(&export->lock);
 	pwm_get_state(pwm, &state);
 	state.period = val;
-	ret = pwm_apply_state(pwm, &state);
+	ret = pwm_apply_might_sleep(pwm, &state);
 	mutex_unlock(&export->lock);
 
 	return ret ? : size;
···
 	mutex_lock(&export->lock);
 	pwm_get_state(pwm, &state);
 	state.duty_cycle = val;
-	ret = pwm_apply_state(pwm, &state);
+	ret = pwm_apply_might_sleep(pwm, &state);
 	mutex_unlock(&export->lock);
 
 	return ret ? : size;
···
 		goto unlock;
 	}
 
-	ret = pwm_apply_state(pwm, &state);
+	ret = pwm_apply_might_sleep(pwm, &state);
 
 unlock:
 	mutex_unlock(&export->lock);
···
 	mutex_lock(&export->lock);
 	pwm_get_state(pwm, &state);
 	state.polarity = polarity;
-	ret = pwm_apply_state(pwm, &state);
+	ret = pwm_apply_might_sleep(pwm, &state);
 	mutex_unlock(&export->lock);
 
 	return ret ? : size;
···
 				 struct pwm_device *pwm,
 				 struct pwm_state *state)
 {
-	int ret = pwm_apply_state(pwm, state);
+	int ret = pwm_apply_might_sleep(pwm, state);
 
 	/* release lock taken in pwm_class_get_state */
 	mutex_unlock(&export->lock);
···
 	 * the kernel it's just not exported.
 	 */
 	parent = device_create(&pwm_class, chip->dev, MKDEV(0, 0), chip,
-			       "pwmchip%d", chip->base);
+			       "pwmchip%d", chip->id);
 	if (IS_ERR(parent)) {
 		dev_warn(chip->dev,
 			 "device_create failed for pwm_chip sysfs export\n");

drivers/regulator/pwm-regulator.c

···
 	pwm_set_relative_duty_cycle(&pstate,
 			drvdata->duty_cycle_table[selector].dutycycle, 100);
 
-	ret = pwm_apply_state(drvdata->pwm, &pstate);
+	ret = pwm_apply_might_sleep(drvdata->pwm, &pstate);
 	if (ret) {
 		dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
 		return ret;
···
 
 	pwm_set_relative_duty_cycle(&pstate, dutycycle, duty_unit);
 
-	ret = pwm_apply_state(drvdata->pwm, &pstate);
+	ret = pwm_apply_might_sleep(drvdata->pwm, &pstate);
 	if (ret) {
 		dev_err(&rdev->dev, "Failed to configure PWM: %d\n", ret);
 		return ret;

drivers/video/backlight/lm3630a_bl.c

···
 
 	pchip->pwmd_state.enabled = pchip->pwmd_state.duty_cycle ? true : false;
 
-	return pwm_apply_state(pchip->pwmd, &pchip->pwmd_state);
+	return pwm_apply_might_sleep(pchip->pwmd, &pchip->pwmd_state);
 }
 
 /* update and get brightness */

drivers/video/backlight/lp855x_bl.c

···
 	state.duty_cycle = div_u64(br * state.period, max_br);
 	state.enabled = state.duty_cycle;
 
-	return pwm_apply_state(lp->pwm, &state);
+	return pwm_apply_might_sleep(lp->pwm, &state);
 }
 
 static int lp855x_bl_update_status(struct backlight_device *bl)

drivers/video/backlight/pwm_bl.c

···
 		pwm_get_state(pb->pwm, &state);
 		state.duty_cycle = compute_duty_cycle(pb, brightness, &state);
 		state.enabled = true;
-		pwm_apply_state(pb->pwm, &state);
+		pwm_apply_might_sleep(pb->pwm, &state);
 
 		pwm_backlight_power_on(pb);
 	} else {
···
 		 * inactive output.
 		 */
 		state.enabled = !pb->power_supply && !pb->enable_gpio;
-		pwm_apply_state(pb->pwm, &state);
+		pwm_apply_might_sleep(pb->pwm, &state);
 	}
 
 	if (pb->notify_after)
···
 	if (!state.period && (data->pwm_period_ns > 0))
 		state.period = data->pwm_period_ns;
 
-	ret = pwm_apply_state(pb->pwm, &state);
+	ret = pwm_apply_might_sleep(pb->pwm, &state);
 	if (ret) {
 		dev_err(&pdev->dev, "failed to apply initial PWM state: %d\n",
 			ret);
···
 	pwm_get_state(pb->pwm, &state);
 	state.duty_cycle = 0;
 	state.enabled = false;
-	pwm_apply_state(pb->pwm, &state);
+	pwm_apply_might_sleep(pb->pwm, &state);
 
 	if (pb->exit)
 		pb->exit(&pdev->dev);
···
 	pwm_get_state(pb->pwm, &state);
 	state.duty_cycle = 0;
 	state.enabled = false;
-	pwm_apply_state(pb->pwm, &state);
+	pwm_apply_might_sleep(pb->pwm, &state);
 }
 
 #ifdef CONFIG_PM_SLEEP
···
 	pwm_get_state(pb->pwm, &state);
 	state.duty_cycle = 0;
 	state.enabled = false;
-	pwm_apply_state(pb->pwm, &state);
+	pwm_apply_might_sleep(pb->pwm, &state);
 
 	if (pb->notify_after)
 		pb->notify_after(pb->dev, 0);

drivers/video/fbdev/ssd1307fb.c

···
 
 		pwm_init_state(par->pwm, &pwmstate);
 		pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
-		pwm_apply_state(par->pwm, &pwmstate);
+		pwm_apply_might_sleep(par->pwm, &pwmstate);
 
 		/* Enable the PWM */
 		pwm_enable(par->pwm);

include/linux/pwm.h

···
  * @label: name of the PWM device
  * @flags: flags associated with the PWM device
  * @hwpwm: per-chip relative index of the PWM device
- * @pwm: global index of the PWM device
  * @chip: PWM chip providing this PWM device
  * @args: PWM arguments
  * @state: last applied state
···
 	const char *label;
 	unsigned long flags;
 	unsigned int hwpwm;
-	unsigned int pwm;
 	struct pwm_chip *chip;
 
 	struct pwm_args args;
···
  * @state: state to fill with the current PWM state
  *
  * The returned PWM state represents the state that was applied by a previous call to
- * pwm_apply_state(). Drivers may have to slightly tweak that state before programming it to
- * hardware. If pwm_apply_state() was never called, this returns either the current hardware
+ * pwm_apply_might_sleep(). Drivers may have to slightly tweak that state before programming it to
+ * hardware. If pwm_apply_might_sleep() was never called, this returns either the current hardware
  * state (if supported) or the default settings.
  */
 static inline void pwm_get_state(const struct pwm_device *pwm,
···
 	return state.enabled;
 }
 
-static inline void pwm_set_period(struct pwm_device *pwm, u64 period)
-{
-	if (pwm)
-		pwm->state.period = period;
-}
-
 static inline u64 pwm_get_period(const struct pwm_device *pwm)
 {
 	struct pwm_state state;
···
 	pwm_get_state(pwm, &state);
 
 	return state.period;
-}
-
-static inline void pwm_set_duty_cycle(struct pwm_device *pwm, unsigned int duty)
-{
-	if (pwm)
-		pwm->state.duty_cycle = duty;
 }
 
 static inline u64 pwm_get_duty_cycle(const struct pwm_device *pwm)
···
 }
 
 /**
- * pwm_init_state() - prepare a new state to be applied with pwm_apply_state()
+ * pwm_init_state() - prepare a new state to be applied with pwm_apply_might_sleep()
  * @pwm: PWM device
  * @state: state to fill with the prepared PWM state
  *
  * This functions prepares a state that can later be tweaked and applied
- * to the PWM device with pwm_apply_state(). This is a convenient function
+ * to the PWM device with pwm_apply_might_sleep(). This is a convenient function
  * that first retrieves the current PWM state and the replaces the period
  * and polarity fields with the reference values defined in pwm->args.
  * Once the function returns, you can adjust the ->enabled and ->duty_cycle
- * fields according to your needs before calling pwm_apply_state().
+ * fields according to your needs before calling pwm_apply_might_sleep().
  *
  * ->duty_cycle is initially set to zero to avoid cases where the current
  * ->duty_cycle value exceed the pwm_args->period one, which would trigger
- * an error if the user calls pwm_apply_state() without adjusting ->duty_cycle
+ * an error if the user calls pwm_apply_might_sleep() without adjusting ->duty_cycle
  * first.
  */
 static inline void pwm_init_state(const struct pwm_device *pwm,
···
  *
  * pwm_init_state(pwm, &state);
  * pwm_set_relative_duty_cycle(&state, 50, 100);
- * pwm_apply_state(pwm, &state);
+ * pwm_apply_might_sleep(pwm, &state);
  *
  * This functions returns -EINVAL if @duty_cycle and/or @scale are
  * inconsistent (@scale == 0 or @duty_cycle > @scale).
···
  * @dev: device providing the PWMs
  * @ops: callbacks for this PWM controller
  * @owner: module providing this chip
- * @base: number of first PWM controlled by this chip
+ * @id: unique number of this PWM chip
  * @npwm: number of PWMs controlled by this chip
  * @of_xlate: request a PWM device given a device tree PWM specifier
  * @of_pwm_n_cells: number of cells expected in the device tree PWM specifier
- * @list: list node for internal use
+ * @atomic: can the driver's ->apply() be called in atomic context
  * @pwms: array of PWM devices allocated by the framework
  */
 struct pwm_chip {
 	struct device *dev;
 	const struct pwm_ops *ops;
 	struct module *owner;
-	int base;
+	unsigned int id;
 	unsigned int npwm;
 
 	struct pwm_device * (*of_xlate)(struct pwm_chip *chip,
 					const struct of_phandle_args *args);
 	unsigned int of_pwm_n_cells;
+	bool atomic;
 
 	/* only used internally by the PWM framework */
-	struct list_head list;
 	struct pwm_device *pwms;
 };
 
 #if IS_ENABLED(CONFIG_PWM)
 /* PWM user APIs */
-int pwm_apply_state(struct pwm_device *pwm, const struct pwm_state *state);
+int pwm_apply_might_sleep(struct pwm_device *pwm, const struct pwm_state *state);
+int pwm_apply_atomic(struct pwm_device *pwm, const struct pwm_state *state);
 int pwm_adjust_config(struct pwm_device *pwm);
 
 /**
···
 
 	state.duty_cycle = duty_ns;
 	state.period = period_ns;
-	return pwm_apply_state(pwm, &state);
+	return pwm_apply_might_sleep(pwm, &state);
 }
 
 /**
···
 		return 0;
 
 	state.enabled = true;
-	return pwm_apply_state(pwm, &state);
+	return pwm_apply_might_sleep(pwm, &state);
 }
 
 /**
···
 		return;
 
 	state.enabled = false;
-	pwm_apply_state(pwm, &state);
+	pwm_apply_might_sleep(pwm, &state);
+}
+
+/**
+ * pwm_might_sleep() - is pwm_apply_atomic() supported?
+ * @pwm: PWM device
+ *
+ * Returns: false if pwm_apply_atomic() can be called from atomic context.
+ */
+static inline bool pwm_might_sleep(struct pwm_device *pwm)
+{
+	return !pwm->chip->atomic;
 }
 
 /* PWM provider APIs */
···
 				       struct fwnode_handle *fwnode,
 				       const char *con_id);
 #else
-static inline int pwm_apply_state(struct pwm_device *pwm,
-				  const struct pwm_state *state)
+static inline bool pwm_might_sleep(struct pwm_device *pwm)
+{
+	return true;
+}
+
+static inline int pwm_apply_might_sleep(struct pwm_device *pwm,
+					const struct pwm_state *state)
 {
 	might_sleep();
-	return -ENOTSUPP;
+	return -EOPNOTSUPP;
+}
+
+static inline int pwm_apply_atomic(struct pwm_device *pwm,
+				   const struct pwm_state *state)
+{
+	return -EOPNOTSUPP;
 }
 
 static inline int pwm_adjust_config(struct pwm_device *pwm)
 {
-	return -ENOTSUPP;
+	return -EOPNOTSUPP;
 }
 
 static inline int pwm_config(struct pwm_device *pwm, int duty_ns,
···
 	state.period = pwm->args.period;
 	state.usage_power = false;
 
-	pwm_apply_state(pwm, &state);
+	pwm_apply_might_sleep(pwm, &state);
+}
+
+/* only for backwards-compatibility, new code should not use this */
+static inline int pwm_apply_state(struct pwm_device *pwm,
+				  const struct pwm_state *state)
+{
+	return pwm_apply_might_sleep(pwm, state);
 }
 
 struct pwm_lookup {