Input: add a driver for GPIO controllable vibrators

Provide a simple driver for GPIO controllable vibrators.
It will be used by the Fairphone 2.

Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

diff --git a/Documentation/devicetree/bindings/input/gpio-vibrator.yaml b/Documentation/devicetree/bindings/input/gpio-vibrator.yaml
new file mode 100644 (file)
index 0000000..903475f
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/gpio-vibrator.yaml
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/bindings/input/gpio-vibrator.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: GPIO vibrator
+
+maintainers:
+  - Luca Weiss <luca@z3ntu.xyz>
+
+description: |+
+  Registers a GPIO device as vibrator, where the on/off capability is controlled by a GPIO.
+
+properties:
+  compatible:
+    const: gpio-vibrator
+
+  enable-gpios:
+    maxItems: 1
+
+  vcc-supply:
+    description: Regulator that provides power
+
+required:
+  - compatible
+  - enable-gpios
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    vibrator {
+        compatible = "gpio-vibrator";
+        enable-gpios = <&msmgpio 86 GPIO_ACTIVE_HIGH>;
+        vcc-supply = <&pm8941_l18>;
+    };

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index e39aef8..16f41ee 100644 (file)
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -290,6 +290,18 @@ config INPUT_GPIO_DECODER
         To compile this driver as a module, choose M here: the module
         will be called gpio_decoder.
 
+config INPUT_GPIO_VIBRA
+       tristate "GPIO vibrator support"
+       depends on GPIOLIB || COMPILE_TEST
+       select INPUT_FF_MEMLESS
+       help
+         Say Y here to get support for GPIO based vibrator devices.
+
+         If unsure, say N.
+
+         To compile this driver as a module, choose M here: the module will be
+         called gpio-vibra.
+
 config INPUT_IXP4XX_BEEPER
        tristate "IXP4XX Beeper support"
        depends on ARCH_IXP4XX

diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 96a6419..d871991 100644 (file)
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_INPUT_DRV2667_HAPTICS)   += drv2667.o
 obj-$(CONFIG_INPUT_GP2A)               += gp2ap002a00f.o
 obj-$(CONFIG_INPUT_GPIO_BEEPER)                += gpio-beeper.o
 obj-$(CONFIG_INPUT_GPIO_DECODER)       += gpio_decoder.o
+obj-$(CONFIG_INPUT_GPIO_VIBRA)         += gpio-vibra.o
 obj-$(CONFIG_INPUT_HISI_POWERKEY)      += hisi_powerkey.o
 obj-$(CONFIG_HP_SDC_RTC)               += hp_sdc_rtc.o
 obj-$(CONFIG_INPUT_IMS_PCU)            += ims-pcu.o

diff --git a/drivers/input/misc/gpio-vibra.c b/drivers/input/misc/gpio-vibra.c
new file mode 100644 (file)
index 0000000..f79f755
--- /dev/null
+++ b/drivers/input/misc/gpio-vibra.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  GPIO vibrator driver
+ *
+ *  Copyright (C) 2019 Luca Weiss <luca@z3ntu.xyz>
+ *
+ *  Based on 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>
+ */
+
+#include <linux/gpio/consumer.h>
+#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/regulator/consumer.h>
+#include <linux/slab.h>
+
+struct gpio_vibrator {
+       struct input_dev *input;
+       struct gpio_desc *gpio;
+       struct regulator *vcc;
+
+       struct work_struct play_work;
+       bool running;
+       bool vcc_on;
+};
+
+static int gpio_vibrator_start(struct gpio_vibrator *vibrator)
+{
+       struct device *pdev = vibrator->input->dev.parent;
+       int err;
+
+       if (!vibrator->vcc_on) {
+               err = regulator_enable(vibrator->vcc);
+               if (err) {
+                       dev_err(pdev, "failed to enable regulator: %d\n", err);
+                       return err;
+               }
+               vibrator->vcc_on = true;
+       }
+
+       gpiod_set_value_cansleep(vibrator->gpio, 1);
+
+       return 0;
+}
+
+static void gpio_vibrator_stop(struct gpio_vibrator *vibrator)
+{
+       gpiod_set_value_cansleep(vibrator->gpio, 0);
+
+       if (vibrator->vcc_on) {
+               regulator_disable(vibrator->vcc);
+               vibrator->vcc_on = false;
+       }
+}
+
+static void gpio_vibrator_play_work(struct work_struct *work)
+{
+       struct gpio_vibrator *vibrator =
+               container_of(work, struct gpio_vibrator, play_work);
+
+       if (vibrator->running)
+               gpio_vibrator_start(vibrator);
+       else
+               gpio_vibrator_stop(vibrator);
+}
+
+static int gpio_vibrator_play_effect(struct input_dev *dev, void *data,
+                                    struct ff_effect *effect)
+{
+       struct gpio_vibrator *vibrator = input_get_drvdata(dev);
+       int level;
+
+       level = effect->u.rumble.strong_magnitude;
+       if (!level)
+               level = effect->u.rumble.weak_magnitude;
+
+       vibrator->running = level;
+       schedule_work(&vibrator->play_work);
+
+       return 0;
+}
+
+static void gpio_vibrator_close(struct input_dev *input)
+{
+       struct gpio_vibrator *vibrator = input_get_drvdata(input);
+
+       cancel_work_sync(&vibrator->play_work);
+       gpio_vibrator_stop(vibrator);
+       vibrator->running = false;
+}
+
+static int gpio_vibrator_probe(struct platform_device *pdev)
+{
+       struct gpio_vibrator *vibrator;
+       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\n",
+                               err);
+               return err;
+       }
+
+       vibrator->gpio = devm_gpiod_get(&pdev->dev, "enable", GPIOD_OUT_LOW);
+       err = PTR_ERR_OR_ZERO(vibrator->gpio);
+       if (err) {
+               if (err != -EPROBE_DEFER)
+                       dev_err(&pdev->dev, "Failed to request main gpio: %d\n",
+                               err);
+               return err;
+       }
+
+       INIT_WORK(&vibrator->play_work, gpio_vibrator_play_work);
+
+       vibrator->input->name = "gpio-vibrator";
+       vibrator->input->id.bustype = BUS_HOST;
+       vibrator->input->close = gpio_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,
+                                     gpio_vibrator_play_effect);
+       if (err) {
+               dev_err(&pdev->dev, "Couldn't create FF dev: %d\n", err);
+               return err;
+       }
+
+       err = input_register_device(vibrator->input);
+       if (err) {
+               dev_err(&pdev->dev, "Couldn't register input dev: %d\n", err);
+               return err;
+       }
+
+       platform_set_drvdata(pdev, vibrator);
+
+       return 0;
+}
+
+static int __maybe_unused gpio_vibrator_suspend(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct gpio_vibrator *vibrator = platform_get_drvdata(pdev);
+
+       cancel_work_sync(&vibrator->play_work);
+       if (vibrator->running)
+               gpio_vibrator_stop(vibrator);
+
+       return 0;
+}
+
+static int __maybe_unused gpio_vibrator_resume(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct gpio_vibrator *vibrator = platform_get_drvdata(pdev);
+
+       if (vibrator->running)
+               gpio_vibrator_start(vibrator);
+
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(gpio_vibrator_pm_ops,
+                        gpio_vibrator_suspend, gpio_vibrator_resume);
+
+#ifdef CONFIG_OF
+static const struct of_device_id gpio_vibra_dt_match_table[] = {
+       { .compatible = "gpio-vibrator" },
+       {}
+};
+MODULE_DEVICE_TABLE(of, gpio_vibra_dt_match_table);
+#endif
+
+static struct platform_driver gpio_vibrator_driver = {
+       .probe  = gpio_vibrator_probe,
+       .driver = {
+               .name   = "gpio-vibrator",
+               .pm     = &gpio_vibrator_pm_ops,
+               .of_match_table = of_match_ptr(gpio_vibra_dt_match_table),
+       },
+};
+module_platform_driver(gpio_vibrator_driver);
+
+MODULE_AUTHOR("Luca Weiss <luca@z3ntu.xy>");
+MODULE_DESCRIPTION("GPIO vibrator driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:gpio-vibrator");