Input: add a driver for PWM controllable vibrators

Provide a simple driver for PWM controllable vibrators.
It will be used by Motorola Droid 4.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

3 files changed, 280 insertions, 0 deletions

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index f47e836eaa0f..9f082a388388 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -581,6 +581,18 @@ config INPUT_PWM_BEEPER
           To compile this driver as a module, choose M here: the module will be
           called pwm-beeper.
 
+config INPUT_PWM_VIBRA
+        tristate "PWM vibrator support"
+        depends on PWM
+        select INPUT_FF_MEMLESS
+        help
+          Say Y here to get support for PWM based vibrator devices.
+
+          If unsure, say N.
+
+          To compile this driver as a module, choose M here: the module will be
+          called pwm-vibra.
+
 config INPUT_RK805_PWRKEY
         tristate "Rockchip RK805 PMIC power key support"
         depends on MFD_RK808
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 1072e0760c19..03fd4262ada9 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -59,6 +59,7 @@ obj-$(CONFIG_INPUT_PM8XXX_VIBRATOR)	+= pm8xxx-vibrator.o
 obj-$(CONFIG_INPUT_PMIC8XXX_PWRKEY)     += pmic8xxx-pwrkey.o
 obj-$(CONFIG_INPUT_POWERMATE)           += powermate.o
 obj-$(CONFIG_INPUT_PWM_BEEPER)          += pwm-beeper.o
+obj-$(CONFIG_INPUT_PWM_VIBRA)           += pwm-vibra.o
 obj-$(CONFIG_INPUT_RB532_BUTTON)        += rb532_button.o
 obj-$(CONFIG_INPUT_REGULATOR_HAPTIC)    += regulator-haptic.o
 obj-$(CONFIG_INPUT_RETU_PWRBUTTON)      += retu-pwrbutton.o
diff --git a/drivers/input/misc/pwm-vibra.c b/drivers/input/misc/pwm-vibra.c
new file mode 100644
index 000000000000..55da191ae550
--- /dev/null
+++ b/drivers/input/misc/pwm-vibra.c
@@ -0,0 +1,267 @@
+/*
+ *  PWM vibrator driver
+ *
+ *  Copyright (C) 2017 Collabora Ltd.
+ *
+ *  Based on previous work from:
+ *  Copyright (C) 2012 Dmitry Torokhov <dmitry.torokhov@gmail.com>
+ *
+ *  Based on PWM beeper driver:
+ *  Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under  the terms of the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ */
+
+#include <linux/input.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/pwm.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+struct pwm_vibrator {
+        struct input_dev *input;
+        struct pwm_device *pwm;
+        struct pwm_device *pwm_dir;
+        struct regulator *vcc;
+
+        struct work_struct play_work;
+        u16 level;
+        u32 direction_duty_cycle;
+};
+
+static int pwm_vibrator_start(struct pwm_vibrator *vibrator)
+{
+        struct device *pdev = vibrator->input->dev.parent;
+        struct pwm_state state;
+        int err;
+
+        err = regulator_enable(vibrator->vcc);
+        if (err) {
+                dev_err(pdev, "failed to enable regulator: %d", err);
+                return err;
+        }
+
+        pwm_get_state(vibrator->pwm, &state);
+        pwm_set_relative_duty_cycle(&state, vibrator->level, 0xffff);
+        state.enabled = true;
+
+        err = pwm_apply_state(vibrator->pwm, &state);
+        if (err) {
+                dev_err(pdev, "failed to apply pwm state: %d", err);
+                return err;
+        }
+
+        if (vibrator->pwm_dir) {
+                pwm_get_state(vibrator->pwm_dir, &state);
+                state.duty_cycle = vibrator->direction_duty_cycle;
+                state.enabled = true;
+
+                err = pwm_apply_state(vibrator->pwm_dir, &state);
+                if (err) {
+                        dev_err(pdev, "failed to apply dir-pwm state: %d", err);
+                        pwm_disable(vibrator->pwm);
+                        return err;
+                }
+        }
+
+        return 0;
+}
+
+static void pwm_vibrator_stop(struct pwm_vibrator *vibrator)
+{
+        regulator_disable(vibrator->vcc);
+
+        if (vibrator->pwm_dir)
+                pwm_disable(vibrator->pwm_dir);
+        pwm_disable(vibrator->pwm);
+}
+
+static void pwm_vibrator_play_work(struct work_struct *work)
+{
+        struct pwm_vibrator *vibrator = container_of(work,
+                                        struct pwm_vibrator, play_work);
+
+        if (vibrator->level)
+                pwm_vibrator_start(vibrator);
+        else
+                pwm_vibrator_stop(vibrator);
+}
+
+static int pwm_vibrator_play_effect(struct input_dev *dev, void *data,
+                                    struct ff_effect *effect)
+{
+        struct pwm_vibrator *vibrator = input_get_drvdata(dev);
+
+        vibrator->level = effect->u.rumble.strong_magnitude;
+        if (!vibrator->level)
+                vibrator->level = effect->u.rumble.weak_magnitude;
+
+        schedule_work(&vibrator->play_work);
+
+        return 0;
+}
+
+static void pwm_vibrator_close(struct input_dev *input)
+{
+        struct pwm_vibrator *vibrator = input_get_drvdata(input);
+
+        cancel_work_sync(&vibrator->play_work);
+        pwm_vibrator_stop(vibrator);
+}
+
+static int pwm_vibrator_probe(struct platform_device *pdev)
+{
+        struct pwm_vibrator *vibrator;
+        struct pwm_state state;
+        int err;
+
+        vibrator = devm_kzalloc(&pdev->dev, sizeof(*vibrator), GFP_KERNEL);
+        if (!vibrator)
+                return -ENOMEM;
+
+        vibrator->input = devm_input_allocate_device(&pdev->dev);
+        if (!vibrator->input)
+                return -ENOMEM;
+
+        vibrator->vcc = devm_regulator_get(&pdev->dev, "vcc");
+        err = PTR_ERR_OR_ZERO(vibrator->vcc);
+        if (err) {
+                if (err != -EPROBE_DEFER)
+                        dev_err(&pdev->dev, "Failed to request regulator: %d",
+                                err);
+                return err;
+        }
+
+        vibrator->pwm = devm_pwm_get(&pdev->dev, "enable");
+        err = PTR_ERR_OR_ZERO(vibrator->pwm);
+        if (err) {
+                if (err != -EPROBE_DEFER)
+                        dev_err(&pdev->dev, "Failed to request main pwm: %d",
+                                err);
+                return err;
+        }
+
+        INIT_WORK(&vibrator->play_work, pwm_vibrator_play_work);
+
+        /* 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);
+        if (err) {
+                dev_err(&pdev->dev, "failed to apply initial PWM state: %d",
+                        err);
+                return err;
+        }
+
+        vibrator->pwm_dir = devm_pwm_get(&pdev->dev, "direction");
+        err = PTR_ERR_OR_ZERO(vibrator->pwm_dir);
+        switch (err) {
+        case 0:
+                /* 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);
+                if (err) {
+                        dev_err(&pdev->dev, "failed to apply initial PWM state: %d",
+                                err);
+                        return err;
+                }
+
+                vibrator->direction_duty_cycle =
+                        pwm_get_period(vibrator->pwm_dir) / 2;
+                device_property_read_u32(&pdev->dev, "direction-duty-cycle-ns",
+                                         &vibrator->direction_duty_cycle);
+                break;
+
+        case -ENODATA:
+                /* Direction PWM is optional */
+                vibrator->pwm_dir = NULL;
+                break;
+
+        default:
+                dev_err(&pdev->dev, "Failed to request direction pwm: %d", err);
+                /* Fall through */
+
+        case -EPROBE_DEFER:
+                return err;
+        }
+
+        vibrator->input->name = "pwm-vibrator";
+        vibrator->input->id.bustype = BUS_HOST;
+        vibrator->input->dev.parent = &pdev->dev;
+        vibrator->input->close = pwm_vibrator_close;
+
+        input_set_drvdata(vibrator->input, vibrator);
+        input_set_capability(vibrator->input, EV_FF, FF_RUMBLE);
+
+        err = input_ff_create_memless(vibrator->input, NULL,
+                                      pwm_vibrator_play_effect);
+        if (err) {
+                dev_err(&pdev->dev, "Couldn't create FF dev: %d", err);
+                return err;
+        }
+
+        err = input_register_device(vibrator->input);
+        if (err) {
+                dev_err(&pdev->dev, "Couldn't register input dev: %d", err);
+                return err;
+        }
+
+        platform_set_drvdata(pdev, vibrator);
+
+        return 0;
+}
+
+static int __maybe_unused pwm_vibrator_suspend(struct device *dev)
+{
+        struct pwm_vibrator *vibrator = dev_get_drvdata(dev);
+
+        cancel_work_sync(&vibrator->play_work);
+        if (vibrator->level)
+                pwm_vibrator_stop(vibrator);
+
+        return 0;
+}
+
+static int __maybe_unused pwm_vibrator_resume(struct device *dev)
+{
+        struct pwm_vibrator *vibrator = dev_get_drvdata(dev);
+
+        if (vibrator->level)
+                pwm_vibrator_start(vibrator);
+
+        return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(pwm_vibrator_pm_ops,
+                         pwm_vibrator_suspend, pwm_vibrator_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id pwm_vibra_dt_match_table[] = {
+        { .compatible = "pwm-vibrator" },
+        {},
+};
+MODULE_DEVICE_TABLE(of, pwm_vibra_dt_match_table);
+#endif
+
+static struct platform_driver pwm_vibrator_driver = {
+        .probe  = pwm_vibrator_probe,
+        .driver = {
+                .name   = "pwm-vibrator",
+                .pm     = &pwm_vibrator_pm_ops,
+                .of_match_table = of_match_ptr(pwm_vibra_dt_match_table),
+        },
+};
+module_platform_driver(pwm_vibrator_driver);
+
+MODULE_AUTHOR("Sebastian Reichel <sre@kernel.org>");
+MODULE_DESCRIPTION("PWM vibrator driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pwm-vibrator");