staging: android: add timed gpio driver to present vibrator control interface to userspace

Change-Id: I725a8620669c4286dda5bcbbbd1b984843a6b006
Signed-off-by: jerry.zhang <jerry.zhang@rock-chips.com>

drivers/staging/android/Makefile

@@ -5,7 +5,7 @@ obj-$(CONFIG_FIQ_DEBUGGER)		+= fiq_debugger/
 
 obj-$(CONFIG_ASHMEM)			+= ashmem.o
 obj-$(CONFIG_ANDROID_TIMED_OUTPUT)	+= timed_output.o
-obj-$(CONFIG_ANDROID_TIMED_GPIO)	+= timed_gpio.o
+obj-$(CONFIG_ANDROID_TIMED_GPIO)	+= timed_gpio.o rk_timed_gpio.o
 obj-$(CONFIG_ANDROID_LOW_MEMORY_KILLER)	+= lowmemorykiller.o
 obj-$(CONFIG_SYNC)			+= sync.o sync_debug.o
 obj-$(CONFIG_SW_SYNC)			+= sw_sync.o

drivers/staging/android/rk_timed_gpio.c

@@ -0,0 +1,161 @@
+/* drivers/staging/android/rk_timed_gpio.c
+ *
+ * Copyright (C) 2012-2016 ROCKCHIP.
+ * Author: jerry <jerry.zhang@rock-chips.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/hrtimer.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_gpio.h>
+#include <linux/of_platform.h>
+#include <linux/wakelock.h>
+#include <linux/workqueue.h>
+#include "timed_output.h"
+
+#define MAX_TIMEOUT        10000	/* 10s */
+
+static struct vibrator {
+	int gpio;
+	struct wake_lock wklock;
+	struct hrtimer timer;
+	struct mutex lock;	/* mutex lock */
+	struct work_struct work;
+} vibdata;
+
+static void rk_vibrator_off(void)
+{
+	gpio_direction_output(vibdata.gpio, 0);
+	gpio_set_value(vibdata.gpio, 0);
+
+	wake_unlock(&vibdata.wklock);
+}
+
+static void rk_vibrator_enable(struct timed_output_dev *sdev, int value)
+{
+	mutex_lock(&vibdata.lock);
+
+	/* cancel previous timer and set GPIO according to value */
+	hrtimer_cancel(&vibdata.timer);
+	cancel_work_sync(&vibdata.work);
+	if (value) {
+		wake_lock(&vibdata.wklock);
+		gpio_direction_output(vibdata.gpio, 1);
+		gpio_set_value(vibdata.gpio, 1);
+
+		if (value > 0) {
+			if (value > MAX_TIMEOUT)
+				value = MAX_TIMEOUT;
+		value += 45;
+		hrtimer_start(&vibdata.timer,
+			ns_to_ktime((u64)value * NSEC_PER_MSEC),
+			HRTIMER_MODE_REL);
+		}
+	} else {
+		rk_vibrator_off();
+	}
+
+	mutex_unlock(&vibdata.lock);
+}
+
+static int rk_vibrator_get_time(struct timed_output_dev *sdev)
+{
+	if (hrtimer_active(&vibdata.timer)) {
+		ktime_t r = hrtimer_get_remaining(&vibdata.timer);
+
+		return ktime_to_ms(r);
+	}
+
+	return 0;
+}
+
+static enum hrtimer_restart rk_vibrator_timer_func(struct hrtimer *timer)
+{
+	schedule_work(&vibdata.work);
+	return HRTIMER_NORESTART;
+}
+
+static void rk_vibrator_work(struct work_struct *work)
+{
+	rk_vibrator_off();
+}
+
+struct timed_output_dev rk_vibrator_driver = {
+	.name = "vibrator",
+	.enable = rk_vibrator_enable,
+	.get_time = rk_vibrator_get_time,
+};
+
+static int vibrator_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct device_node *np = pdev->dev.of_node;
+
+	vibdata.gpio = of_get_named_gpio_flags(np, "vibrator-gpio", 0, NULL);
+	if (!gpio_is_valid(vibdata.gpio))
+		return -1;
+
+	hrtimer_init(&vibdata.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	vibdata.timer.function = rk_vibrator_timer_func;
+	INIT_WORK(&vibdata.work, rk_vibrator_work);
+
+	ret = devm_gpio_request(&pdev->dev, vibdata.gpio, "vibrator");
+	if (ret < 0)
+		return ret;
+
+	wake_lock_init(&vibdata.wklock, WAKE_LOCK_SUSPEND, "vibrator");
+	mutex_init(&vibdata.lock);
+	ret = timed_output_dev_register(&rk_vibrator_driver);
+	if (ret < 0)
+		goto err_to_dev_reg;
+
+	return 0;
+
+err_to_dev_reg:
+	mutex_destroy(&vibdata.lock);
+	wake_lock_destroy(&vibdata.wklock);
+
+	return ret;
+}
+
+static int vibrator_remove(struct platform_device *pdev)
+{
+	mutex_destroy(&vibdata.lock);
+	wake_lock_destroy(&vibdata.wklock);
+	timed_output_dev_unregister(&rk_vibrator_driver);
+
+	return 0;
+}
+
+static const struct of_device_id vibrator_of_match[] = {
+	{ .compatible = "rk-vibrator-gpio" },
+	{ }
+};
+
+static struct platform_driver vibrator_driver = {
+	.probe = vibrator_probe,
+	.remove = vibrator_remove,
+	.driver = {
+		.name           = "rk-vibrator",
+		.of_match_table = of_match_ptr(vibrator_of_match),
+	},
+};
+
+module_platform_driver(vibrator_driver);
+
+MODULE_AUTHOR("jerry.zhang@rock-chips.com");
+MODULE_DESCRIPTION("RK Vibrator driver");
+MODULE_LICENSE("GPL");