1 files changed, 94 insertions, 62 deletions

diff --git a/drivers/input/misc/pwm-beeper.c b/drivers/input/misc/pwm-beeper.c
index 5f9655d49a65..e53801dbd560 100644
--- a/drivers/input/misc/pwm-beeper.c
+++ b/drivers/input/misc/pwm-beeper.c
@@ -14,6 +14,7 @@
  */
 
 #include <linux/input.h>
+#include <linux/regulator/consumer.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/of.h>
@@ -25,29 +26,62 @@
 struct pwm_beeper {
         struct input_dev *input;
         struct pwm_device *pwm;
+        struct regulator *amplifier;
         struct work_struct work;
         unsigned long period;
+        bool suspended;
+        bool amplifier_on;
 };
 
 #define HZ_TO_NANOSECONDS(x) (1000000000UL/(x))
 
-static void __pwm_beeper_set(struct pwm_beeper *beeper)
+static int pwm_beeper_on(struct pwm_beeper *beeper, unsigned long period)
 {
-        unsigned long period = beeper->period;
+        struct pwm_state state;
+        int error;
+
+        pwm_get_state(beeper->pwm, &state);
+
+        state.enabled = true;
+        state.period = period;
+        pwm_set_relative_duty_cycle(&state, 50, 100);
+
+        error = pwm_apply_state(beeper->pwm, &state);
+        if (error)
+                return error;
+
+        if (!beeper->amplifier_on) {
+                error = regulator_enable(beeper->amplifier);
+                if (error) {
+                        pwm_disable(beeper->pwm);
+                        return error;
+                }
+
+                beeper->amplifier_on = true;
+        }
+
+        return 0;
+}
 
-        if (period) {
-                pwm_config(beeper->pwm, period / 2, period);
-                pwm_enable(beeper->pwm);
-        } else
-                pwm_disable(beeper->pwm);
+static void pwm_beeper_off(struct pwm_beeper *beeper)
+{
+        if (beeper->amplifier_on) {
+                regulator_disable(beeper->amplifier);
+                beeper->amplifier_on = false;
+        }
+
+        pwm_disable(beeper->pwm);
 }
 
 static void pwm_beeper_work(struct work_struct *work)
 {
-        struct pwm_beeper *beeper =
-                container_of(work, struct pwm_beeper, work);
+        struct pwm_beeper *beeper = container_of(work, struct pwm_beeper, work);
+        unsigned long period = READ_ONCE(beeper->period);
 
-        __pwm_beeper_set(beeper);
+        if (period)
+                pwm_beeper_on(beeper, period);
+        else
+                pwm_beeper_off(beeper);
 }
 
 static int pwm_beeper_event(struct input_dev *input,
@@ -73,7 +107,8 @@ static int pwm_beeper_event(struct input_dev *input,
         else
                 beeper->period = HZ_TO_NANOSECONDS(value);
 
-        schedule_work(&beeper->work);
+        if (!beeper->suspended)
+                schedule_work(&beeper->work);
 
         return 0;
 }
@@ -81,9 +116,7 @@ static int pwm_beeper_event(struct input_dev *input,
 static void pwm_beeper_stop(struct pwm_beeper *beeper)
 {
         cancel_work_sync(&beeper->work);
-
-        if (beeper->period)
-                pwm_disable(beeper->pwm);
+        pwm_beeper_off(beeper);
 }
 
 static void pwm_beeper_close(struct input_dev *input)
@@ -95,41 +128,50 @@ static void pwm_beeper_close(struct input_dev *input)
 
 static int pwm_beeper_probe(struct platform_device *pdev)
 {
-        unsigned long pwm_id = (unsigned long)dev_get_platdata(&pdev->dev);
+        struct device *dev = &pdev->dev;
         struct pwm_beeper *beeper;
+        struct pwm_state state;
         int error;
 
-        beeper = kzalloc(sizeof(*beeper), GFP_KERNEL);
+        beeper = devm_kzalloc(dev, sizeof(*beeper), GFP_KERNEL);
         if (!beeper)
                 return -ENOMEM;
 
-        beeper->pwm = pwm_get(&pdev->dev, NULL);
+        beeper->pwm = devm_pwm_get(dev, NULL);
         if (IS_ERR(beeper->pwm)) {
-                dev_dbg(&pdev->dev, "unable to request PWM, trying legacy API\n");
-                beeper->pwm = pwm_request(pwm_id, "pwm beeper");
+                error = PTR_ERR(beeper->pwm);
+                if (error != -EPROBE_DEFER)
+                        dev_err(dev, "Failed to request PWM device: %d\n",
+                                error);
+                return error;
         }
 
-        if (IS_ERR(beeper->pwm)) {
-                error = PTR_ERR(beeper->pwm);
-                dev_err(&pdev->dev, "Failed to request pwm device: %d\n", error);
-                goto err_free;
+        /* 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);
+        if (error) {
+                dev_err(dev, "failed to apply initial PWM state: %d\n",
+                        error);
+                return error;
         }
 
-        /*
-         * FIXME: pwm_apply_args() should be removed when switching to
-         * the atomic PWM API.
-         */
-        pwm_apply_args(beeper->pwm);
+        beeper->amplifier = devm_regulator_get(dev, "amp");
+        if (IS_ERR(beeper->amplifier)) {
+                error = PTR_ERR(beeper->amplifier);
+                if (error != -EPROBE_DEFER)
+                        dev_err(dev, "Failed to get 'amp' regulator: %d\n",
+                                error);
+                return error;
+        }
 
         INIT_WORK(&beeper->work, pwm_beeper_work);
 
-        beeper->input = input_allocate_device();
+        beeper->input = devm_input_allocate_device(dev);
         if (!beeper->input) {
-                dev_err(&pdev->dev, "Failed to allocate input device\n");
-                error = -ENOMEM;
-                goto err_pwm_free;
+                dev_err(dev, "Failed to allocate input device\n");
+                return -ENOMEM;
         }
-        beeper->input->dev.parent = &pdev->dev;
 
         beeper->input->name = "pwm-beeper";
         beeper->input->phys = "pwm/input0";
@@ -138,8 +180,8 @@ static int pwm_beeper_probe(struct platform_device *pdev)
         beeper->input->id.product = 0x0001;
         beeper->input->id.version = 0x0100;
 
-        beeper->input->evbit[0] = BIT(EV_SND);
-        beeper->input->sndbit[0] = BIT(SND_TONE) | BIT(SND_BELL);
+        input_set_capability(beeper->input, EV_SND, SND_TONE);
+        input_set_capability(beeper->input, EV_SND, SND_BELL);
 
         beeper->input->event = pwm_beeper_event;
         beeper->input->close = pwm_beeper_close;
@@ -148,41 +190,28 @@ static int pwm_beeper_probe(struct platform_device *pdev)
 
         error = input_register_device(beeper->input);
         if (error) {
-                dev_err(&pdev->dev, "Failed to register input device: %d\n", error);
-                goto err_input_free;
+                dev_err(dev, "Failed to register input device: %d\n", error);
+                return error;
         }
 
         platform_set_drvdata(pdev, beeper);
 
         return 0;
-
-err_input_free:
-        input_free_device(beeper->input);
-err_pwm_free:
-        pwm_free(beeper->pwm);
-err_free:
-        kfree(beeper);
-
-        return error;
-}
-
-static int pwm_beeper_remove(struct platform_device *pdev)
-{
-        struct pwm_beeper *beeper = platform_get_drvdata(pdev);
-
-        input_unregister_device(beeper->input);
-
-        pwm_free(beeper->pwm);
-
-        kfree(beeper);
-
-        return 0;
 }
 
 static int __maybe_unused pwm_beeper_suspend(struct device *dev)
 {
         struct pwm_beeper *beeper = dev_get_drvdata(dev);
 
+        /*
+         * Spinlock is taken here is not to protect write to
+         * beeper->suspended, but to ensure that pwm_beeper_event
+         * does not re-submit work once flag is set.
+         */
+        spin_lock_irq(&beeper->input->event_lock);
+        beeper->suspended = true;
+        spin_unlock_irq(&beeper->input->event_lock);
+
         pwm_beeper_stop(beeper);
 
         return 0;
@@ -192,8 +221,12 @@ static int __maybe_unused pwm_beeper_resume(struct device *dev)
 {
         struct pwm_beeper *beeper = dev_get_drvdata(dev);
 
-        if (beeper->period)
-                __pwm_beeper_set(beeper);
+        spin_lock_irq(&beeper->input->event_lock);
+        beeper->suspended = false;
+        spin_unlock_irq(&beeper->input->event_lock);
+
+        /* Let worker figure out if we should resume beeping */
+        schedule_work(&beeper->work);
 
         return 0;
 }
@@ -211,7 +244,6 @@ MODULE_DEVICE_TABLE(of, pwm_beeper_match);
 
 static struct platform_driver pwm_beeper_driver = {
         .probe  = pwm_beeper_probe,
-        .remove = pwm_beeper_remove,
         .driver = {
                 .name   = "pwm-beeper",
                 .pm     = &pwm_beeper_pm_ops,