input: misc: add regulator-haptic driver

Haptic motor controlled by voltage in regulator. And driver support
force-feedback interface.

Signed-off-by: Hyunhee Kim <hyunhee.kim@samsung.com>
[code cleanup and add detailed description by Jaewon Kim]
Signed-off-by: Jaewon Kim <jaewon02.kim@samsung.com>

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index bb698e1..df022bb 100644 (file)
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -93,6 +93,17 @@ config INPUT_BMA150
          To compile this driver as a module, choose M here: the
          module will be called bma150.
 
+config INPUT_REGULATOR_HAPTIC
+       tristate "regulator haptics support"
+       select INPUT_FF_MEMLESS
+       help
+         This option enables device driver support for the haptic controlled
+         by regulator. This driver supports ff-memless interface
+         from input framework.
+
+         To compile this driver as a module, choose M here: the
+         module will be called regulator-haptic.
+
 config INPUT_PCSPKR
        tristate "PC Speaker support"
        depends on PCSPKR_PLATFORM

diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index d7fc17f..88c60df 100644 (file)
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_INPUT_DA9055_ONKEY)      += da9055_onkey.o
 obj-$(CONFIG_INPUT_DM355EVM)           += dm355evm_keys.o
 obj-$(CONFIG_INPUT_GP2A)               += gp2ap002a00f.o
 obj-$(CONFIG_INPUT_GPIO_TILT_POLLED)   += gpio_tilt_polled.o
+obj-$(CONFIG_INPUT_REGULATOR_HAPTIC)   += regulator-haptic.o
 obj-$(CONFIG_HP_SDC_RTC)               += hp_sdc_rtc.o
 obj-$(CONFIG_INPUT_IMS_PCU)            += ims-pcu.o
 obj-$(CONFIG_INPUT_IXP4XX_BEEPER)      += ixp4xx-beeper.o

diff --git a/drivers/input/misc/regulator-haptic.c b/drivers/input/misc/regulator-haptic.c
new file mode 100644 (file)
index 0000000..1cdde98
--- /dev/null
+++ b/drivers/input/misc/regulator-haptic.c
@@ -0,0 +1,227 @@
+/*
+ * Regulator haptic driver
+ *
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ *
+ * Author: Hyunhee Kim <hyunhee.kim@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/regulator/consumer.h>
+#include <linux/of.h>
+
+#define MAX_MAGNITUDE          0xffff
+#define DEFAULT_MIN_MICROVOLT  1100000
+#define DEFAULT_MAX_MICROVOLT  2700000
+
+/*
+ * struct regulator
+ *
+ * One for each consumer device.
+ */
+struct regulator_haptic {
+       struct device *dev;
+       struct input_dev *input_dev;
+       struct work_struct work;
+       bool enabled;
+       struct regulator *regulator;
+       struct mutex mutex;
+       int max_mV;
+       int min_mV;
+       int intensity; /* mV */
+       int level;
+};
+
+static void regulator_haptic_enable(
+                       struct regulator_haptic *haptic, bool enable)
+{
+       int ret;
+
+       mutex_lock(&haptic->mutex);
+       if (enable && !haptic->enabled) {
+               haptic->enabled = true;
+               ret = regulator_enable(haptic->regulator);
+               if (ret)
+                       dev_err(haptic->dev, "failed to enable regulator\n");
+       } else if (!enable && haptic->enabled) {
+               haptic->enabled = false;
+               ret = regulator_disable(haptic->regulator);
+               if (ret)
+                       dev_err(haptic->dev, "failed to disable regulator\n");
+       }
+
+       if (haptic->enabled)
+               regulator_set_voltage(haptic->regulator,
+                       haptic->intensity * 1000, haptic->max_mV * 1000);
+
+       mutex_unlock(&haptic->mutex);
+}
+
+static void regulator_haptic_work(struct work_struct *work)
+{
+       struct regulator_haptic *haptic = container_of(work,
+                                                      struct regulator_haptic,
+                                                      work);
+       if (haptic->level)
+               regulator_haptic_enable(haptic, true);
+       else
+               regulator_haptic_enable(haptic, false);
+
+}
+
+static int regulator_haptic_play(struct input_dev *input, void *data,
+                               struct ff_effect *effect)
+{
+       struct regulator_haptic *haptic = input_get_drvdata(input);
+
+       haptic->level = effect->u.rumble.strong_magnitude;
+       if (!haptic->level)
+               haptic->level = effect->u.rumble.weak_magnitude;
+
+       haptic->intensity =
+               (haptic->max_mV - haptic->min_mV) * haptic->level /
+               MAX_MAGNITUDE;
+       haptic->intensity = haptic->intensity + haptic->min_mV;
+
+       if (haptic->intensity > haptic->max_mV)
+               haptic->intensity = haptic->max_mV;
+       if (haptic->intensity < haptic->min_mV)
+               haptic->intensity = haptic->min_mV;
+
+       schedule_work(&haptic->work);
+
+       return 0;
+}
+
+static void regulator_haptic_close(struct input_dev *input)
+{
+       struct regulator_haptic *haptic = input_get_drvdata(input);
+
+       cancel_work_sync(&haptic->work);
+       regulator_haptic_enable(haptic, false);
+}
+
+static void regulator_haptic_parse_dt(struct regulator_haptic *haptic,
+                               struct device *dev)
+{
+       struct device_node *node = dev->of_node;
+       int max_uV, min_uV;
+
+       if (of_property_read_u32(node, "max-microvolt", &max_uV)) {
+               dev_err(haptic->dev, "unable to parse max-microvolt\n");
+               max_uV = DEFAULT_MAX_MICROVOLT;
+       }
+       if (of_property_read_u32(node, "min-microvolt", &min_uV)) {
+               dev_err(haptic->dev, "unable to parse min-microvolt\n");
+               min_uV = DEFAULT_MIN_MICROVOLT;
+       }
+
+       haptic->max_mV = max_uV / 1000;
+       haptic->min_mV = min_uV / 1000;
+
+}
+
+static int regulator_haptic_probe(struct platform_device *pdev)
+{
+       struct regulator_haptic *haptic;
+       struct input_dev *input_dev;
+       int error;
+
+       haptic = devm_kzalloc(&pdev->dev, sizeof(*haptic), GFP_KERNEL);
+       if (!haptic) {
+               dev_err(&pdev->dev, "unable to allocate memory for haptic\n");
+               return -ENOMEM;
+       }
+
+       input_dev = devm_input_allocate_device(&pdev->dev);
+       if (!input_dev) {
+               dev_err(&pdev->dev, "unable to allocate memory\n");
+               return  -ENOMEM;
+       }
+
+       INIT_WORK(&haptic->work, regulator_haptic_work);
+       mutex_init(&haptic->mutex);
+       haptic->input_dev = input_dev;
+       haptic->dev = &pdev->dev;
+       haptic->regulator = devm_regulator_get(&pdev->dev, "haptic");
+       if (IS_ERR(haptic->regulator)) {
+               error = PTR_ERR(haptic->regulator);
+               dev_err(&pdev->dev, "unable to get regulator, err: %d\n",
+                       error);
+               return error;
+       }
+
+       regulator_haptic_parse_dt(haptic, haptic->dev);
+       haptic->input_dev->name = "regulator:haptic";
+       haptic->input_dev->dev.parent = &pdev->dev;
+       haptic->input_dev->close = regulator_haptic_close;
+       haptic->enabled = false;
+       input_set_drvdata(haptic->input_dev, haptic);
+       input_set_capability(haptic->input_dev, EV_FF, FF_RUMBLE);
+
+       error = input_ff_create_memless(input_dev, NULL,
+                                     regulator_haptic_play);
+       if (error) {
+               dev_err(&pdev->dev,
+                       "input_ff_create_memless() failed: %d\n",
+                       error);
+               goto err_put_regulator;
+       }
+
+       error = input_register_device(haptic->input_dev);
+       if (error) {
+               dev_err(&pdev->dev,
+                       "couldn't register input device: %d\n",
+                       error);
+               goto err_destroy_ff;
+       }
+
+       platform_set_drvdata(pdev, haptic);
+
+       return 0;
+
+err_destroy_ff:
+       input_ff_destroy(haptic->input_dev);
+err_put_regulator:
+       regulator_put(haptic->regulator);
+
+       return error;
+}
+
+static int regulator_haptic_remove(struct platform_device *pdev)
+{
+       struct regulator_haptic *haptic = platform_get_drvdata(pdev);
+
+       input_unregister_device(haptic->input_dev);
+       devm_regulator_put(haptic->regulator);
+
+       return 0;
+}
+
+static struct of_device_id regulator_haptic_dt_match[] = {
+       { .compatible = "linux,regulator-haptic" },
+       {},
+};
+
+static struct platform_driver regulator_haptic_driver = {
+       .driver         = {
+               .name   = "regulator-haptic",
+               .owner  = THIS_MODULE,
+               .of_match_table = regulator_haptic_dt_match,
+       },
+       .probe          = regulator_haptic_probe,
+       .remove         = regulator_haptic_remove,
+};
+module_platform_driver(regulator_haptic_driver);
+
+MODULE_ALIAS("platform:regulator-haptic");
+MODULE_DESCRIPTION("Regulator haptic driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Hyunhee Kim <hyunhee.kim@samsung.com>");