12 #include <linux/pwm.h>
21 #include <dt-bindings/pwm/pwm.h>
24 #include <trace/events/pwm.h>
85 static int pwm_device_request(struct pwm_device *pwm, const char *label)  in pwm_device_request()  argument
89 	if (test_bit(PWMF_REQUESTED, &pwm->flags))  in pwm_device_request()
92 	if (!try_module_get(pwm->chip->ops->owner))  in pwm_device_request()
95 	if (pwm->chip->ops->request) {  in pwm_device_request()
96 		err = pwm->chip->ops->request(pwm->chip, pwm);  in pwm_device_request()
98 			module_put(pwm->chip->ops->owner);  in pwm_device_request()
103 	if (pwm->chip->ops->get_state) {  in pwm_device_request()
113 		err = pwm->chip->ops->get_state(pwm->chip, pwm, &state);  in pwm_device_request()
114 		trace_pwm_get(pwm, &state, err);  in pwm_device_request()
117 			pwm->state = state;  in pwm_device_request()
120 			pwm->last = pwm->state;  in pwm_device_request()
123 	set_bit(PWMF_REQUESTED, &pwm->flags);  in pwm_device_request()
124 	pwm->label = label;  in pwm_device_request()
132 	struct pwm_device *pwm;  in of_pwm_xlate_with_flags()  local
144 	pwm = pwm_request_from_chip(chip, args->args[0], NULL);  in of_pwm_xlate_with_flags()
145 	if (IS_ERR(pwm))  in of_pwm_xlate_with_flags()
146 		return pwm;  in of_pwm_xlate_with_flags()
148 	pwm->args.period = args->args[1];  in of_pwm_xlate_with_flags()
149 	pwm->args.polarity = PWM_POLARITY_NORMAL;  in of_pwm_xlate_with_flags()
153 			pwm->args.polarity = PWM_POLARITY_INVERSED;  in of_pwm_xlate_with_flags()
156 	return pwm;  in of_pwm_xlate_with_flags()
163 	struct pwm_device *pwm;  in of_pwm_single_xlate()  local
172 	pwm = pwm_request_from_chip(chip, 0, NULL);  in of_pwm_single_xlate()
173 	if (IS_ERR(pwm))  in of_pwm_single_xlate()
174 		return pwm;  in of_pwm_single_xlate()
176 	pwm->args.period = args->args[0];  in of_pwm_single_xlate()
177 	pwm->args.polarity = PWM_POLARITY_NORMAL;  in of_pwm_single_xlate()
180 		pwm->args.polarity = PWM_POLARITY_INVERSED;  in of_pwm_single_xlate()
182 	return pwm;  in of_pwm_single_xlate()
194 		if (of_property_read_u32(chip->dev->of_node, "#pwm-cells",  in of_pwmchip_add()
212  * pwm_set_chip_data() - set private chip data for a PWM
213  * @pwm: PWM device
218 int pwm_set_chip_data(struct pwm_device *pwm, void *data)  in pwm_set_chip_data()  argument
220 	if (!pwm)  in pwm_set_chip_data()
223 	pwm->chip_data = data;  in pwm_set_chip_data()
230  * pwm_get_chip_data() - get private chip data for a PWM
231  * @pwm: PWM device
233  * Returns: A pointer to the chip-private data for the PWM device.
235 void *pwm_get_chip_data(struct pwm_device *pwm)  in pwm_get_chip_data()  argument
237 	return pwm ? pwm->chip_data : NULL;  in pwm_get_chip_data()
256  * pwmchip_add() - register a new PWM chip
257  * @chip: the PWM chip to add
259  * Register a new PWM chip.
265 	struct pwm_device *pwm;  in pwmchip_add()  local
275 	chip->pwms = kcalloc(chip->npwm, sizeof(*pwm), GFP_KERNEL);  in pwmchip_add()
291 		pwm = &chip->pwms[i];  in pwmchip_add()
293 		pwm->chip = chip;  in pwmchip_add()
294 		pwm->pwm = chip->base + i;  in pwmchip_add()
295 		pwm->hwpwm = i;  in pwmchip_add()
312  * pwmchip_remove() - remove a PWM chip
313  * @chip: the PWM chip to remove
315  * Removes a PWM chip.
354  * pwm_request_from_chip() - request a PWM device relative to a PWM chip
355  * @chip: PWM chip
356  * @index: per-chip index of the PWM to request
357  * @label: a literal description string of this PWM
359  * Returns: A pointer to the PWM device at the given index of the given PWM
361  * specified PWM chip or if the PWM device cannot be requested.
367 	struct pwm_device *pwm;  in pwm_request_from_chip()  local
374 	pwm = &chip->pwms[index];  in pwm_request_from_chip()
376 	err = pwm_device_request(pwm, label);  in pwm_request_from_chip()
378 		pwm = ERR_PTR(err);  in pwm_request_from_chip()
381 	return pwm;  in pwm_request_from_chip()
385 static void pwm_apply_debug(struct pwm_device *pwm,  in pwm_apply_debug()  argument
388 	struct pwm_state *last = &pwm->last;  in pwm_apply_debug()
389 	struct pwm_chip *chip = pwm->chip;  in pwm_apply_debug()
405 	err = chip->ops->get_state(chip, pwm, &s1);  in pwm_apply_debug()
406 	trace_pwm_get(pwm, &s1, err);  in pwm_apply_debug()
464 	err = chip->ops->apply(chip, pwm, &s1);  in pwm_apply_debug()
465 	trace_pwm_apply(pwm, &s1, err);  in pwm_apply_debug()
473 	err = chip->ops->get_state(chip, pwm, last);  in pwm_apply_debug()
474 	trace_pwm_get(pwm, last, err);  in pwm_apply_debug()
492  * pwm_apply_might_sleep() - atomically apply a new state to a PWM device
493  * @pwm: PWM device
496 int pwm_apply_might_sleep(struct pwm_device *pwm, const struct pwm_state *state)  in pwm_apply_might_sleep()  argument
510 	if (!pwm || !state || !state->period ||  in pwm_apply_might_sleep()
514 	chip = pwm->chip;  in pwm_apply_might_sleep()
516 	if (state->period == pwm->state.period &&  in pwm_apply_might_sleep()
517 	    state->duty_cycle == pwm->state.duty_cycle &&  in pwm_apply_might_sleep()
518 	    state->polarity == pwm->state.polarity &&  in pwm_apply_might_sleep()
519 	    state->enabled == pwm->state.enabled &&  in pwm_apply_might_sleep()
520 	    state->usage_power == pwm->state.usage_power)  in pwm_apply_might_sleep()
523 	err = chip->ops->apply(chip, pwm, state);  in pwm_apply_might_sleep()
524 	trace_pwm_apply(pwm, state, err);  in pwm_apply_might_sleep()
528 	pwm->state = *state;  in pwm_apply_might_sleep()
531 	 * only do this after pwm->state was applied as some  in pwm_apply_might_sleep()
534 	pwm_apply_debug(pwm, state);  in pwm_apply_might_sleep()
541  * pwm_capture() - capture and report a PWM signal
542  * @pwm: PWM device
548 int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result,  in pwm_capture()  argument
553 	if (!pwm || !pwm->chip->ops)  in pwm_capture()
556 	if (!pwm->chip->ops->capture)  in pwm_capture()
560 	err = pwm->chip->ops->capture(pwm->chip, pwm, result, timeout);  in pwm_capture()
568  * pwm_adjust_config() - adjust the current PWM config to the PWM arguments
569  * @pwm: PWM device
571  * This function will adjust the PWM config to the PWM arguments provided
572  * by the DT or PWM lookup table. This is particularly useful to adapt
575 int pwm_adjust_config(struct pwm_device *pwm)  in pwm_adjust_config()  argument
580 	pwm_get_args(pwm, &pargs);  in pwm_adjust_config()
581 	pwm_get_state(pwm, &state);  in pwm_adjust_config()
584 	 * If the current period is zero it means that either the PWM driver  in pwm_adjust_config()
585 	 * does not support initial state retrieval or the PWM has not yet  in pwm_adjust_config()
596 		return pwm_apply_might_sleep(pwm, &state);  in pwm_adjust_config()
600 	 * Adjust the PWM duty cycle/period based on the period value provided  in pwm_adjust_config()
601 	 * in PWM args.  in pwm_adjust_config()
619 	return pwm_apply_might_sleep(pwm, &state);  in pwm_adjust_config()
641 					       struct pwm_device *pwm)  in pwm_device_link_add()  argument
647 		 * No device for the PWM consumer has been provided. It may  in pwm_device_link_add()
648 		 * impact the PM sequence ordering: the PWM supplier may get  in pwm_device_link_add()
651 		dev_warn(pwm->chip->dev,  in pwm_device_link_add()
656 	dl = device_link_add(dev, pwm->chip->dev, DL_FLAG_AUTOREMOVE_CONSUMER);  in pwm_device_link_add()
659 			dev_name(pwm->chip->dev));  in pwm_device_link_add()
667  * of_pwm_get() - request a PWM via the PWM framework
668  * @dev: device for PWM consumer
669  * @np: device node to get the PWM from
672  * Returns the PWM device parsed from the phandle and index specified in the
674  * Values parsed from the device tree are stored in the returned PWM device
677  * If con_id is NULL, the first PWM device listed in the "pwms" property will
678  * be requested. Otherwise the "pwm-names" property is used to do a reverse
679  * lookup of the PWM index. This also means that the "pwm-names" property
680  * becomes mandatory for devices that look up the PWM device via the con_id
683  * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
689 	struct pwm_device *pwm = NULL;  in of_pwm_get()  local
697 		index = of_property_match_string(np, "pwm-names", con_id);  in of_pwm_get()
702 	err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index,  in of_pwm_get()
712 			pr_err("%s(): PWM chip not found\n", __func__);  in of_pwm_get()
714 		pwm = ERR_CAST(chip);  in of_pwm_get()
718 	pwm = chip->of_xlate(chip, &args);  in of_pwm_get()
719 	if (IS_ERR(pwm))  in of_pwm_get()
722 	dl = pwm_device_link_add(dev, pwm);  in of_pwm_get()
725 		pwm_put(pwm);  in of_pwm_get()
726 		pwm = ERR_CAST(dl);  in of_pwm_get()
732 	 * "pwm-names" property if it exists. Otherwise use the name of  in of_pwm_get()
736 		err = of_property_read_string_index(np, "pwm-names", index,  in of_pwm_get()
742 	pwm->label = con_id;  in of_pwm_get()
747 	return pwm;  in of_pwm_get()
751  * acpi_pwm_get() - request a PWM via parsing "pwms" property in ACPI
754  * Returns the PWM device parsed from the fwnode and index specified in the
756  * Values parsed from the device tree are stored in the returned PWM device
762  *     { <PWM device reference>, <PWM index>, <PWM period> [, <PWM flags>]}}
764  * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
769 	struct pwm_device *pwm;  in acpi_pwm_get()  local
787 	pwm = pwm_request_from_chip(chip, args.args[0], NULL);  in acpi_pwm_get()
788 	if (IS_ERR(pwm))  in acpi_pwm_get()
789 		return pwm;  in acpi_pwm_get()
791 	pwm->args.period = args.args[1];  in acpi_pwm_get()
792 	pwm->args.polarity = PWM_POLARITY_NORMAL;  in acpi_pwm_get()
795 		pwm->args.polarity = PWM_POLARITY_INVERSED;  in acpi_pwm_get()
797 	return pwm;  in acpi_pwm_get()
801  * pwm_add_table() - register PWM device consumers
818  * pwm_remove_table() - unregister PWM device consumers
835  * pwm_get() - look up and request a PWM device
836  * @dev: device for PWM consumer
840  * a device tree, a PWM chip and a relative index is looked up via a table
843  * Once a PWM chip has been found the specified PWM device will be requested
846  * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
853 	struct pwm_device *pwm;  in pwm_get()  local
867 		pwm = acpi_pwm_get(fwnode);  in pwm_get()
868 		if (!IS_ERR(pwm) || PTR_ERR(pwm) != -ENOENT)  in pwm_get()
869 			return pwm;  in pwm_get()
879 	 * If a match is found, the provider PWM chip is looked up by name  in pwm_get()
880 	 * and a PWM device is requested using the PWM device per-chip index.  in pwm_get()
930 	 * the PWM chip lookup. This can be used to work around driver load  in pwm_get()
943 	pwm = pwm_request_from_chip(chip, chosen->index, con_id ?: dev_id);  in pwm_get()
944 	if (IS_ERR(pwm))  in pwm_get()
945 		return pwm;  in pwm_get()
947 	dl = pwm_device_link_add(dev, pwm);  in pwm_get()
949 		pwm_put(pwm);  in pwm_get()
953 	pwm->args.period = chosen->period;  in pwm_get()
954 	pwm->args.polarity = chosen->polarity;  in pwm_get()
956 	return pwm;  in pwm_get()
961  * pwm_put() - release a PWM device
962  * @pwm: PWM device
964 void pwm_put(struct pwm_device *pwm)  in pwm_put()  argument
966 	if (!pwm)  in pwm_put()
971 	if (!test_and_clear_bit(PWMF_REQUESTED, &pwm->flags)) {  in pwm_put()
972 		pr_warn("PWM device already freed\n");  in pwm_put()
976 	if (pwm->chip->ops->free)  in pwm_put()
977 		pwm->chip->ops->free(pwm->chip, pwm);  in pwm_put()
979 	pwm_set_chip_data(pwm, NULL);  in pwm_put()
980 	pwm->label = NULL;  in pwm_put()
982 	module_put(pwm->chip->ops->owner);  in pwm_put()
988 static void devm_pwm_release(void *pwm)  in devm_pwm_release()  argument
990 	pwm_put(pwm);  in devm_pwm_release()
995  * @dev: device for PWM consumer
998  * This function performs like pwm_get() but the acquired PWM device will
1001  * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
1006 	struct pwm_device *pwm;  in devm_pwm_get()  local
1009 	pwm = pwm_get(dev, con_id);  in devm_pwm_get()
1010 	if (IS_ERR(pwm))  in devm_pwm_get()
1011 		return pwm;  in devm_pwm_get()
1013 	ret = devm_add_action_or_reset(dev, devm_pwm_release, pwm);  in devm_pwm_get()
1017 	return pwm;  in devm_pwm_get()
1022  * devm_fwnode_pwm_get() - request a resource managed PWM from firmware node
1023  * @dev: device for PWM consumer
1024  * @fwnode: firmware node to get the PWM from
1027  * Returns the PWM device parsed from the firmware node. See of_pwm_get() and
1030  * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
1037 	struct pwm_device *pwm = ERR_PTR(-ENODEV);  in devm_fwnode_pwm_get()  local
1041 		pwm = of_pwm_get(dev, to_of_node(fwnode), con_id);  in devm_fwnode_pwm_get()
1043 		pwm = acpi_pwm_get(fwnode);  in devm_fwnode_pwm_get()
1044 	if (IS_ERR(pwm))  in devm_fwnode_pwm_get()
1045 		return pwm;  in devm_fwnode_pwm_get()
1047 	ret = devm_add_action_or_reset(dev, devm_pwm_release, pwm);  in devm_fwnode_pwm_get()
1051 	return pwm;  in devm_fwnode_pwm_get()
1061 		struct pwm_device *pwm = &chip->pwms[i];  in pwm_dbg_show()  local
1064 		pwm_get_state(pwm, &state);  in pwm_dbg_show()
1066 		seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label);  in pwm_dbg_show()
1068 		if (test_bit(PWMF_REQUESTED, &pwm->flags))  in pwm_dbg_show()
1110 	seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private,  in pwm_seq_show()
1131 	debugfs_create_file("pwm", 0444, NULL, NULL, &pwm_debugfs_fops);  in pwm_debugfs_init()