Input: add a driver for PWM controllable vibrators
authorSebastian Reichel <sebastian.reichel@collabora.co.uk>
Mon, 4 Sep 2017 16:30:03 +0000 (09:30 -0700)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Mon, 4 Sep 2017 19:13:24 +0000 (12:13 -0700)
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>
Documentation/devicetree/bindings/input/pwm-vibrator.txt [new file with mode: 0644]
drivers/input/misc/Kconfig
drivers/input/misc/Makefile
drivers/input/misc/pwm-vibra.c [new file with mode: 0644]

diff --git a/Documentation/devicetree/bindings/input/pwm-vibrator.txt b/Documentation/devicetree/bindings/input/pwm-vibrator.txt
new file mode 100644 (file)
index 0000000..09145d1
--- /dev/null
@@ -0,0 +1,66 @@
+* PWM vibrator device tree bindings
+
+Registers a PWM device as vibrator. It is expected, that the vibrator's
+strength increases based on the duty cycle of the enable PWM channel
+(100% duty cycle meaning strongest vibration, 0% meaning no vibration).
+
+The binding supports an optional direction PWM channel, that can be
+driven at fixed duty cycle. If available this is can be used to increase
+the vibration effect of some devices.
+
+Required properties:
+- compatible: should contain "pwm-vibrator"
+- pwm-names: Should contain "enable" and optionally "direction"
+- pwms: Should contain a PWM handle for each entry in pwm-names
+
+Optional properties:
+- vcc-supply: Phandle for the regulator supplying power
+- direction-duty-cycle-ns: Duty cycle of the direction PWM channel in
+                           nanoseconds, defaults to 50% of the channel's
+                          period.
+
+Example from Motorola Droid 4:
+
+&omap4_pmx_core {
+       vibrator_direction_pin: pinmux_vibrator_direction_pin {
+               pinctrl-single,pins = <
+               OMAP4_IOPAD(0x1ce, PIN_OUTPUT | MUX_MODE1) /* dmtimer8_pwm_evt (gpio_27) */
+               >;
+       };
+
+       vibrator_enable_pin: pinmux_vibrator_enable_pin {
+               pinctrl-single,pins = <
+               OMAP4_IOPAD(0X1d0, PIN_OUTPUT | MUX_MODE1) /* dmtimer9_pwm_evt (gpio_28) */
+               >;
+       };
+};
+
+/ {
+       pwm8: dmtimer-pwm {
+               pinctrl-names = "default";
+               pinctrl-0 = <&vibrator_direction_pin>;
+
+               compatible = "ti,omap-dmtimer-pwm";
+               #pwm-cells = <3>;
+               ti,timers = <&timer8>;
+               ti,clock-source = <0x01>;
+       };
+
+       pwm9: dmtimer-pwm {
+               pinctrl-names = "default";
+               pinctrl-0 = <&vibrator_enable_pin>;
+
+               compatible = "ti,omap-dmtimer-pwm";
+               #pwm-cells = <3>;
+               ti,timers = <&timer9>;
+               ti,clock-source = <0x01>;
+       };
+
+       vibrator {
+               compatible = "pwm-vibrator";
+               pwms = <&pwm8 0 1000000000 0>,
+                      <&pwm9 0 1000000000 0>;
+               pwm-names = "enable", "direction";
+               direction-duty-cycle-ns = <1000000000>;
+       };
+};
index f47e836eaa0f6de06071a3299be8f91b61687db5..9f082a388388b8aa542905d5c58b126c70b99cfb 100644 (file)
@@ -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
index 1072e0760c1989f28c0236faaf9e408912e80d88..03fd4262ada9b9cfe64a676f664f0bd99f5ac5c0 100644 (file)
@@ -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 (file)
index 0000000..55da191
--- /dev/null
@@ -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");