Input: add new vibrator driver for various MSM SOCs

This patch adds a new vibrator driver that supports various Qualcomm
MSM SOCs. Driver was tested on a LG Nexus 5 (hammerhead) phone.

Signed-off-by: Brian Masney <[e-mail]>
Reviewed-by: Rob Herring <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

Documentation/devicetree/bindings/input/msm-vibrator.txt

···
+* Device tree bindings for the Qualcomm MSM vibrator
+
+Required properties:
+
+  - compatible: Should be one of
+		"qcom,msm8226-vibrator"
+		"qcom,msm8974-vibrator"
+  - reg: the base address and length of the IO memory for the registers.
+  - pinctrl-names: set to default.
+  - pinctrl-0: phandles pointing to pin configuration nodes. See
+               Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
+  - clock-names: set to pwm
+  - clocks: phandle of the clock. See
+            Documentation/devicetree/bindings/clock/clock-bindings.txt
+  - enable-gpios: GPIO that enables the vibrator.
+
+Optional properties:
+
+  - vcc-supply: phandle to the regulator that provides power to the sensor.
+
+Example from a LG Nexus 5 (hammerhead) phone:
+
+vibrator@fd8c3450 {
+	reg = <0xfd8c3450 0x400>;
+	compatible = "qcom,msm8974-vibrator";
+
+	vcc-supply = <&pm8941_l19>;
+
+	clocks = <&mmcc CAMSS_GP1_CLK>;
+	clock-names = "pwm";
+
+	enable-gpios = <&msmgpio 60 GPIO_ACTIVE_HIGH>;
+
+	pinctrl-names = "default";
+	pinctrl-0 = <&vibrator_pin>;
+};

drivers/input/misc/Kconfig

···
 	  To compile this driver as a module, choose M here: the
 	  module will be called e3x0_button.
 
+config INPUT_MSM_VIBRATOR
+	tristate "Qualcomm MSM vibrator driver"
+	select INPUT_FF_MEMLESS
+	help
+	  Support for the vibrator that is found on various Qualcomm MSM
+	  SOCs.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called msm_vibrator.
+
 config INPUT_PCSPKR
 	tristate "PC Speaker support"
 	depends on PCSPKR_PLATFORM

drivers/input/misc/Makefile

···
 obj-$(CONFIG_INPUT_MAX8997_HAPTIC)	+= max8997_haptic.o
 obj-$(CONFIG_INPUT_MC13783_PWRBUTTON)	+= mc13783-pwrbutton.o
 obj-$(CONFIG_INPUT_MMA8450)		+= mma8450.o
+obj-$(CONFIG_INPUT_MSM_VIBRATOR)	+= msm-vibrator.o
 obj-$(CONFIG_INPUT_PALMAS_PWRBUTTON)	+= palmas-pwrbutton.o
 obj-$(CONFIG_INPUT_PCAP)		+= pcap_keys.o
 obj-$(CONFIG_INPUT_PCF50633_PMU)	+= pcf50633-input.o

drivers/input/misc/msm-vibrator.c

···
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Qualcomm MSM vibrator driver
+ *
+ * Copyright (c) 2018 Brian Masney <[e-mail]>
+ *
+ * Based on qcom,pwm-vibrator.c from:
+ * Copyright (c) 2018 Jonathan Marek <[e-mail]>
+ *
+ * Based on msm_pwm_vibrator.c from downstream Android sources:
+ * Copyright (C) 2009-2014 LGE, Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/input.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+#define REG_CMD_RCGR           0x00
+#define REG_CFG_RCGR           0x04
+#define REG_M                  0x08
+#define REG_N                  0x0C
+#define REG_D                  0x10
+#define REG_CBCR               0x24
+#define MMSS_CC_M_DEFAULT      1
+
+struct msm_vibrator {
+	struct input_dev *input;
+	struct mutex mutex;
+	struct work_struct worker;
+	void __iomem *base;
+	struct regulator *vcc;
+	struct clk *clk;
+	struct gpio_desc *enable_gpio;
+	u16 magnitude;
+	bool enabled;
+};
+
+static void msm_vibrator_write(struct msm_vibrator *vibrator, int offset,
+			       u32 value)
+{
+	writel(value, vibrator->base + offset);
+}
+
+static int msm_vibrator_start(struct msm_vibrator *vibrator)
+{
+	int d_reg_val, ret = 0;
+
+	mutex_lock(&vibrator->mutex);
+
+	if (!vibrator->enabled) {
+		ret = clk_set_rate(vibrator->clk, 24000);
+		if (ret) {
+			dev_err(&vibrator->input->dev,
+				"Failed to set clock rate: %d\n", ret);
+			goto unlock;
+		}
+
+		ret = clk_prepare_enable(vibrator->clk);
+		if (ret) {
+			dev_err(&vibrator->input->dev,
+				"Failed to enable clock: %d\n", ret);
+			goto unlock;
+		}
+
+		ret = regulator_enable(vibrator->vcc);
+		if (ret) {
+			dev_err(&vibrator->input->dev,
+				"Failed to enable regulator: %d\n", ret);
+			clk_disable(vibrator->clk);
+			goto unlock;
+		}
+
+		gpiod_set_value_cansleep(vibrator->enable_gpio, 1);
+
+		vibrator->enabled = true;
+	}
+
+	d_reg_val = 127 - ((126 * vibrator->magnitude) / 0xffff);
+	msm_vibrator_write(vibrator, REG_CFG_RCGR,
+			   (2 << 12) | /* dual edge mode */
+			   (0 << 8) |  /* cxo */
+			   (7 << 0));
+	msm_vibrator_write(vibrator, REG_M, 1);
+	msm_vibrator_write(vibrator, REG_N, 128);
+	msm_vibrator_write(vibrator, REG_D, d_reg_val);
+	msm_vibrator_write(vibrator, REG_CMD_RCGR, 1);
+	msm_vibrator_write(vibrator, REG_CBCR, 1);
+
+unlock:
+	mutex_unlock(&vibrator->mutex);
+
+	return ret;
+}
+
+static void msm_vibrator_stop(struct msm_vibrator *vibrator)
+{
+	mutex_lock(&vibrator->mutex);
+
+	if (vibrator->enabled) {
+		gpiod_set_value_cansleep(vibrator->enable_gpio, 0);
+		regulator_disable(vibrator->vcc);
+		clk_disable(vibrator->clk);
+		vibrator->enabled = false;
+	}
+
+	mutex_unlock(&vibrator->mutex);
+}
+
+static void msm_vibrator_worker(struct work_struct *work)
+{
+	struct msm_vibrator *vibrator = container_of(work,
+						     struct msm_vibrator,
+						     worker);
+
+	if (vibrator->magnitude)
+		msm_vibrator_start(vibrator);
+	else
+		msm_vibrator_stop(vibrator);
+}
+
+static int msm_vibrator_play_effect(struct input_dev *dev, void *data,
+				    struct ff_effect *effect)
+{
+	struct msm_vibrator *vibrator = input_get_drvdata(dev);
+
+	mutex_lock(&vibrator->mutex);
+
+	if (effect->u.rumble.strong_magnitude > 0)
+		vibrator->magnitude = effect->u.rumble.strong_magnitude;
+	else
+		vibrator->magnitude = effect->u.rumble.weak_magnitude;
+
+	mutex_unlock(&vibrator->mutex);
+
+	schedule_work(&vibrator->worker);
+
+	return 0;
+}
+
+static void msm_vibrator_close(struct input_dev *input)
+{
+	struct msm_vibrator *vibrator = input_get_drvdata(input);
+
+	cancel_work_sync(&vibrator->worker);
+	msm_vibrator_stop(vibrator);
+}
+
+static int msm_vibrator_probe(struct platform_device *pdev)
+{
+	struct msm_vibrator *vibrator;
+	struct resource *res;
+	int ret;
+
+	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");
+	if (IS_ERR(vibrator->vcc)) {
+		if (PTR_ERR(vibrator->vcc) != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Failed to get regulator: %ld\n",
+				PTR_ERR(vibrator->vcc));
+		return PTR_ERR(vibrator->vcc);
+	}
+
+	vibrator->enable_gpio = devm_gpiod_get(&pdev->dev, "enable",
+					       GPIOD_OUT_LOW);
+	if (IS_ERR(vibrator->enable_gpio)) {
+		if (PTR_ERR(vibrator->enable_gpio) != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Failed to get enable gpio: %ld\n",
+				PTR_ERR(vibrator->enable_gpio));
+		return PTR_ERR(vibrator->enable_gpio);
+	}
+
+	vibrator->clk = devm_clk_get(&pdev->dev, "pwm");
+	if (IS_ERR(vibrator->clk)) {
+		if (PTR_ERR(vibrator->clk) != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Failed to lookup pwm clock: %ld\n",
+				PTR_ERR(vibrator->clk));
+		return PTR_ERR(vibrator->clk);
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "Failed to get platform resource\n");
+		return -ENODEV;
+	}
+
+	vibrator->base = devm_ioremap(&pdev->dev, res->start,
+				     resource_size(res));
+	if (!vibrator->base) {
+		dev_err(&pdev->dev, "Failed to iomap resource: %ld\n",
+			PTR_ERR(vibrator->base));
+		return -ENOMEM;
+	}
+
+	vibrator->enabled = false;
+	mutex_init(&vibrator->mutex);
+	INIT_WORK(&vibrator->worker, msm_vibrator_worker);
+
+	vibrator->input->name = "msm-vibrator";
+	vibrator->input->id.bustype = BUS_HOST;
+	vibrator->input->close = msm_vibrator_close;
+
+	input_set_drvdata(vibrator->input, vibrator);
+	input_set_capability(vibrator->input, EV_FF, FF_RUMBLE);
+
+	ret = input_ff_create_memless(vibrator->input, NULL,
+				      msm_vibrator_play_effect);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to create ff memless: %d", ret);
+		return ret;
+	}
+
+	ret = input_register_device(vibrator->input);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to register input device: %d", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, vibrator);
+
+	return 0;
+}
+
+static int __maybe_unused msm_vibrator_suspend(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct msm_vibrator *vibrator = platform_get_drvdata(pdev);
+
+	cancel_work_sync(&vibrator->worker);
+
+	if (vibrator->enabled)
+		msm_vibrator_stop(vibrator);
+
+	return 0;
+}
+
+static int __maybe_unused msm_vibrator_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct msm_vibrator *vibrator = platform_get_drvdata(pdev);
+
+	if (vibrator->enabled)
+		msm_vibrator_start(vibrator);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(msm_vibrator_pm_ops, msm_vibrator_suspend,
+			 msm_vibrator_resume);
+
+static const struct of_device_id msm_vibrator_of_match[] = {
+	{ .compatible = "qcom,msm8226-vibrator" },
+	{ .compatible = "qcom,msm8974-vibrator" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, msm_vibrator_of_match);
+
+static struct platform_driver msm_vibrator_driver = {
+	.probe	= msm_vibrator_probe,
+	.driver	= {
+		.name = "msm-vibrator",
+		.pm = &msm_vibrator_pm_ops,
+		.of_match_table = of_match_ptr(msm_vibrator_of_match),
+	},
+};
+module_platform_driver(msm_vibrator_driver);
+
+MODULE_AUTHOR("Brian Masney <[e-mail]>");
+MODULE_DESCRIPTION("Qualcomm MSM vibrator driver");
+MODULE_LICENSE("GPL");