[PATCH] media: i2c: Add driver for DW9719 VCM

[Daniel Scally <djrscally@gmail.com>]

Add a driver for the DW9719 VCM. The driver creates a v4l2 subdevice
and registers a control to set the desired focus.

Signed-off-by: Daniel Scally <djrscally@gmail.com>
---
 MAINTAINERS                |   7 +
 drivers/media/i2c/Kconfig  |  11 +
 drivers/media/i2c/Makefile |   1 +
 drivers/media/i2c/dw9719.c | 427 +++++++++++++++++++++++++++++++++++++
 4 files changed, 446 insertions(+)
 create mode 100644 drivers/media/i2c/dw9719.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 6e0763ff55db..99d2bc961bc0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5789,6 +5789,13 @@ T:	git git://linuxtv.org/media_tree.git
 F:	Documentation/devicetree/bindings/media/i2c/dongwoon,dw9714.txt
 F:	drivers/media/i2c/dw9714.c
 
+DONGWOON DW9719 LENS VOICE COIL DRIVER
+M:	Daniel Scally <djrscally@gmail.com>
+L:	linux-media@vger.kernel.org
+S:	Maintained
+T:	git git://linuxtv.org/media_tree.git
+F:	drivers/media/i2c/dw9719.c
+
 DONGWOON DW9768 LENS VOICE COIL DRIVER
 M:	Dongchun Zhu <dongchun.zhu@mediatek.com>
 L:	linux-media@vger.kernel.org
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 8761a90a7a86..096c9be6c402 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -1465,6 +1465,17 @@ config VIDEO_DW9714
 	  capability. This is designed for linear control of
 	  voice coil motors, controlled via I2C serial interface.
 
+config VIDEO_DW9719
+	tristate "DW9719 lens voice coil support"
+	depends on I2C && VIDEO_V4L2
+	select MEDIA_CONTROLLER
+	select VIDEO_V4L2_SUBDEV_API
+	select V4L2_ASYNC
+	help
+	  This is a driver for the DW9719 camera lens voice coil.
+	  This is designed for linear control of  voice coil motors,
+	  controlled via I2C serial interface.
+
 config VIDEO_DW9768
 	tristate "DW9768 lens voice coil support"
 	depends on I2C && VIDEO_V4L2
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index b01f6cd05ee8..ba8b31d79222 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -24,6 +24,7 @@ obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o
 obj-$(CONFIG_VIDEO_AD5820)  += ad5820.o
 obj-$(CONFIG_VIDEO_AK7375)  += ak7375.o
 obj-$(CONFIG_VIDEO_DW9714)  += dw9714.o
+obj-$(CONFIG_VIDEO_DW9719)  += dw9719.o
 obj-$(CONFIG_VIDEO_DW9768)  += dw9768.o
 obj-$(CONFIG_VIDEO_DW9807_VCM)  += dw9807-vcm.o
 obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o
diff --git a/drivers/media/i2c/dw9719.c b/drivers/media/i2c/dw9719.c
new file mode 100644
index 000000000000..8451c75b696b
--- /dev/null
+++ b/drivers/media/i2c/dw9719.c
@@ -0,0 +1,427 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2012 Intel Corporation
+
+/*
+ * Based on linux/modules/camera/drivers/media/i2c/imx/dw9719.c in this repo:
+ * https://github.com/ZenfoneArea/android_kernel_asus_zenfone5
+ */
+
+#include <asm/unaligned.h>
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+#include <linux/types.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-subdev.h>
+
+#define DW9719_MAX_FOCUS_POS	1023
+#define DW9719_CTRL_STEPS	16
+#define DW9719_CTRL_DELAY_US	1000
+#define DELAY_MAX_PER_STEP_NS	(1000000 * 1023)
+
+#define DW9719_INFO			0
+#define DW9719_ID			0xF1
+#define DW9719_CONTROL			2
+#define DW9719_VCM_CURRENT		3
+
+#define DW9719_MODE			6
+#define DW9719_VCM_FREQ			7
+
+#define DW9719_MODE_SAC3		0x40
+#define DW9719_DEFAULT_VCM_FREQ		0x60
+#define DW9719_ENABLE_RINGING		0x02
+
+#define NUM_REGULATORS			2
+
+#define to_dw9719_device(x) container_of(x, struct dw9719_device, sd)
+
+struct dw9719_device {
+	struct device *dev;
+	struct i2c_client *client;
+	struct regulator_bulk_data regulators[NUM_REGULATORS];
+	struct v4l2_subdev sd;
+
+	struct dw9719_v4l2_ctrls {
+		struct v4l2_ctrl_handler handler;
+		struct v4l2_ctrl *focus;
+	} ctrls;
+};
+
+static int dw9719_i2c_rd8(struct i2c_client *client, u8 reg, u8 *val)
+{
+	struct i2c_msg msg[2];
+	u8 buf[2] = { reg };
+	int ret;
+
+	msg[0].addr = client->addr;
+	msg[0].flags = 0;
+	msg[0].len = 1;
+	msg[0].buf = buf;
+
+	msg[1].addr = client->addr;
+	msg[1].flags = I2C_M_RD;
+	msg[1].len = 1;
+	msg[1].buf = &buf[1];
+	*val = 0;
+
+	ret = i2c_transfer(client->adapter, msg, 2);
+	if (ret < 0)
+		return ret;
+
+	*val = buf[1];
+
+	return 0;
+}
+
+static int dw9719_i2c_wr8(struct i2c_client *client, u8 reg, u8 val)
+{
+	struct i2c_msg msg;
+	int ret;
+
+	u8 buf[2] = { reg, val };
+
+	msg.addr = client->addr;
+	msg.flags = 0;
+	msg.len = sizeof(buf);
+	msg.buf = buf;
+
+	ret = i2c_transfer(client->adapter, &msg, 1);
+
+	return ret < 0 ? ret : 0;
+}
+
+static int dw9719_i2c_wr16(struct i2c_client *client, u8 reg, u16 val)
+{
+	struct i2c_msg msg;
+	u8 buf[3] = { reg };
+	int ret;
+
+	put_unaligned_be16(val, buf + 1);
+
+	msg.addr = client->addr;
+	msg.flags = 0;
+	msg.len = sizeof(buf);
+	msg.buf = buf;
+
+	ret = i2c_transfer(client->adapter, &msg, 1);
+
+	return ret < 0 ? ret : 0;
+}
+
+static int dw9719_detect(struct dw9719_device *dw9719)
+{
+	int ret;
+	u8 val;
+
+	ret = dw9719_i2c_rd8(dw9719->client, DW9719_INFO, &val);
+	if (ret < 0)
+		return ret;
+
+	if (val != DW9719_ID) {
+		dev_err(dw9719->dev, "Failed to detect correct id\n");
+		ret = -ENXIO;
+	}
+
+	return 0;
+}
+
+static int dw9719_power_down(struct dw9719_device *dw9719)
+{
+	return regulator_bulk_disable(NUM_REGULATORS, dw9719->regulators);
+}
+
+static int dw9719_power_up(struct dw9719_device *dw9719)
+{
+	int ret;
+
+	ret = regulator_bulk_enable(NUM_REGULATORS, dw9719->regulators);
+	if (ret)
+		return ret;
+
+	/* Jiggle SCL pin to wake up device */
+	ret = dw9719_i2c_wr8(dw9719->client, DW9719_CONTROL, 1);
+
+	/* Need 100us to transit from SHUTDOWN to STANDBY*/
+	usleep_range(100, 1000);
+
+	ret = dw9719_i2c_wr8(dw9719->client, DW9719_CONTROL,
+			     DW9719_ENABLE_RINGING);
+	if (ret < 0)
+		goto fail_powerdown;
+
+	ret = dw9719_i2c_wr8(dw9719->client, DW9719_MODE, DW9719_MODE_SAC3);
+	if (ret < 0)
+		goto fail_powerdown;
+
+	ret = dw9719_i2c_wr8(dw9719->client, DW9719_VCM_FREQ,
+			     DW9719_DEFAULT_VCM_FREQ);
+	if (ret < 0)
+		goto fail_powerdown;
+
+	return 0;
+
+fail_powerdown:
+	dw9719_power_down(dw9719);
+	return ret;
+}
+
+static int dw9719_t_focus_abs(struct dw9719_device *dw9719, s32 value)
+{
+	int ret;
+
+	value = clamp(value, 0, DW9719_MAX_FOCUS_POS);
+	ret = dw9719_i2c_wr16(dw9719->client, DW9719_VCM_CURRENT, value);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+static int dw9719_set_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct dw9719_device *dw9719 = container_of(ctrl->handler,
+						    struct dw9719_device,
+						    ctrls.handler);
+	int ret;
+
+	/* Only apply changes to the controls if the device is powered up */
+	if (!pm_runtime_get_if_in_use(dw9719->dev))
+		return 0;
+
+	switch (ctrl->id) {
+	case V4L2_CID_FOCUS_ABSOLUTE:
+		ret = dw9719_t_focus_abs(dw9719, ctrl->val);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	pm_runtime_put(dw9719->dev);
+
+	return ret;
+}
+
+static const struct v4l2_ctrl_ops dw9719_ctrl_ops = {
+	.s_ctrl = dw9719_set_ctrl,
+};
+
+static int __maybe_unused dw9719_suspend(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct dw9719_device *dw9719 = to_dw9719_device(sd);
+	int ret;
+	int val;
+
+	for (val = dw9719->ctrls.focus->val; val >= 0;
+	     val -= DW9719_CTRL_STEPS) {
+		ret = dw9719_t_focus_abs(dw9719, val);
+		if (ret)
+			return ret;
+
+		usleep_range(DW9719_CTRL_DELAY_US, DW9719_CTRL_DELAY_US + 10);
+	}
+
+	return dw9719_power_down(dw9719);
+}
+
+static int __maybe_unused dw9719_resume(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct dw9719_device *dw9719 = to_dw9719_device(sd);
+	int current_focus = dw9719->ctrls.focus->val;
+	int ret;
+	int val;
+
+	ret = dw9719_power_up(dw9719);
+	if (ret)
+		return ret;
+
+	for (val = current_focus % DW9719_CTRL_STEPS; val < current_focus;
+	     val += DW9719_CTRL_STEPS) {
+		ret = dw9719_t_focus_abs(dw9719, val);
+		if (ret)
+			goto err_power_down;
+
+		usleep_range(DW9719_CTRL_DELAY_US, DW9719_CTRL_DELAY_US + 10);
+	}
+
+	return 0;
+
+err_power_down:
+	dw9719_power_down(dw9719);
+	return ret;
+}
+
+static int dw9719_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	return pm_runtime_resume_and_get(sd->dev);
+}
+
+static int dw9719_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	pm_runtime_put(sd->dev);
+
+	return 0;
+}
+
+static const struct v4l2_subdev_internal_ops dw9719_internal_ops = {
+	.open = dw9719_open,
+	.close = dw9719_close,
+};
+
+static int dw9719_init_controls(struct dw9719_device *dw9719)
+{
+	const struct v4l2_ctrl_ops *ops = &dw9719_ctrl_ops;
+	int ret;
+
+	ret = v4l2_ctrl_handler_init(&dw9719->ctrls.handler, 1);
+	if (ret)
+		return ret;
+
+	dw9719->ctrls.focus = v4l2_ctrl_new_std(&dw9719->ctrls.handler, ops,
+						V4L2_CID_FOCUS_ABSOLUTE, 0,
+						DW9719_MAX_FOCUS_POS, 1, 0);
+
+	if (dw9719->ctrls.handler.error) {
+		dev_err(dw9719->dev, "Error initialising v4l2 ctrls\n");
+		ret = dw9719->ctrls.handler.error;
+		goto err_free_handler;
+	}
+
+	dw9719->sd.ctrl_handler = &dw9719->ctrls.handler;
+
+	return ret;
+
+err_free_handler:
+	v4l2_ctrl_handler_free(&dw9719->ctrls.handler);
+	return ret;
+}
+
+static const struct v4l2_subdev_ops dw9719_ops = { };
+
+static int dw9719_probe(struct i2c_client *client)
+{
+	struct dw9719_device *dw9719;
+	int ret;
+
+	dw9719 = devm_kzalloc(&client->dev, sizeof(*dw9719), GFP_KERNEL);
+	if (!dw9719)
+		return -ENOMEM;
+
+	dw9719->client = client;
+	dw9719->dev = &client->dev;
+
+	dw9719->regulators[0].supply = "vdd";
+	/*
+	 * The DW9719 has only the 1 VDD voltage input, but some PMICs such as
+	 * the TPS68470 PMIC have I2C passthrough capability, to disconnect the
+	 * sensor's I2C pins from the I2C bus when the sensors VSIO (Sensor-IO)
+	 * is off, because some sensors then short these pins to ground;
+	 * and the DW9719 might sit behind this passthrough, this it needs to
+	 * enable VSIO as that will also enable the I2C passthrough.
+	 */
+	dw9719->regulators[1].supply = "vsio";
+
+	ret = devm_regulator_bulk_get(&client->dev, NUM_REGULATORS,
+				      dw9719->regulators);
+	if (ret)
+		return dev_err_probe(&client->dev, ret, "getting regulators\n");
+
+	v4l2_i2c_subdev_init(&dw9719->sd, client, &dw9719_ops);
+	dw9719->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	dw9719->sd.internal_ops = &dw9719_internal_ops;
+
+	ret = dw9719_init_controls(dw9719);
+	if (ret)
+		return ret;
+
+	ret = media_entity_pads_init(&dw9719->sd.entity, 0, NULL);
+	if (ret < 0)
+		goto err_free_ctrl_handler;
+
+	dw9719->sd.entity.function = MEDIA_ENT_F_LENS;
+
+	/*
+	 * We need the driver to work in the event that pm runtime is disable in
+	 * the kernel, so power up and verify the chip now. In the event that
+	 * runtime pm is disabled this will leave the chip on, so that the lens
+	 * will work.
+	 */
+
+	ret = dw9719_power_up(dw9719);
+	if (ret)
+		goto err_cleanup_media;
+
+	ret = dw9719_detect(dw9719);
+	if (ret)
+		goto err_powerdown;
+
+	pm_runtime_set_active(&client->dev);
+	pm_runtime_get_noresume(&client->dev);
+	pm_runtime_enable(&client->dev);
+
+	ret = v4l2_async_register_subdev(&dw9719->sd);
+	if (ret < 0)
+		goto err_pm_runtime;
+
+	pm_runtime_set_autosuspend_delay(&client->dev, 1000);
+	pm_runtime_use_autosuspend(&client->dev);
+	pm_runtime_put_autosuspend(&client->dev);
+
+	return ret;
+
+err_pm_runtime:
+	pm_runtime_disable(&client->dev);
+	pm_runtime_put_noidle(&client->dev);
+err_powerdown:
+	dw9719_power_down(dw9719);
+err_cleanup_media:
+	media_entity_cleanup(&dw9719->sd.entity);
+err_free_ctrl_handler:
+	v4l2_ctrl_handler_free(&dw9719->ctrls.handler);
+
+	return ret;
+}
+
+static int dw9719_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct dw9719_device *dw9719 = container_of(sd, struct dw9719_device,
+						    sd);
+
+	pm_runtime_disable(&client->dev);
+	v4l2_async_unregister_subdev(sd);
+	v4l2_ctrl_handler_free(&dw9719->ctrls.handler);
+	media_entity_cleanup(&dw9719->sd.entity);
+
+	return 0;
+}
+
+static const struct i2c_device_id dw9719_id_table[] = {
+	{ "dw9719" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, dw9719_id_table);
+
+static const struct dev_pm_ops dw9719_pm_ops = {
+	SET_RUNTIME_PM_OPS(dw9719_suspend, dw9719_resume, NULL)
+};
+
+static struct i2c_driver dw9719_i2c_driver = {
+	.driver = {
+		.name = "dw9719",
+		.pm = &dw9719_pm_ops,
+	},
+	.probe_new = dw9719_probe,
+	.remove = dw9719_remove,
+	.id_table = dw9719_id_table,
+};
+module_i2c_driver(dw9719_i2c_driver);
+
+MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
+MODULE_DESCRIPTION("DW9719 VCM Driver");
+MODULE_LICENSE("GPL");
-- 
2.25.1