[PATCH v1 2/2] media: i2c: Add GT97xx VCM driver

[Zhi Mao]

Add a V4L2 sub-device driver for Giantec GT97xx VCM.

Signed-off-by: Zhi Mao <zhi.mao@xxxxxxxxxxxx>
---
 drivers/media/i2c/Kconfig  |  13 ++
 drivers/media/i2c/Makefile |   1 +
 drivers/media/i2c/gt97xx.c | 436 +++++++++++++++++++++++++++++++++++++
 3 files changed, 450 insertions(+)
 create mode 100644 drivers/media/i2c/gt97xx.c

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 56f276b920ab..fcb330cebfe0 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -759,6 +759,19 @@ config VIDEO_DW9807_VCM
 	  capability. This is designed for linear control of
 	  voice coil motors, controlled via I2C serial interface.
 
+config VIDEO_GT97XX
+	tristate "GT97xx lens voice coil support"
+	depends on I2C && VIDEO_DEV
+	select MEDIA_CONTROLLER
+	select VIDEO_V4L2_SUBDEV_API
+	select V4L2_FWNODE
+	select V4L2_CCI_I2C
+	help
+	  This is a driver for the GT97xx camera lens voice coil.
+	  GT97xx is a 10 bit DAC with 100mA output current sink
+	  capability. It is designed for linear control of
+	  voice coil motors, controlled via I2C serial interface.
+
 endmenu
 
 menu "Flash devices"
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index dfbe6448b549..af36a7aa3d12 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -39,6 +39,7 @@ obj-$(CONFIG_VIDEO_DW9807_VCM) += dw9807-vcm.o
 obj-$(CONFIG_VIDEO_ET8EK8) += et8ek8/
 obj-$(CONFIG_VIDEO_GC0308) += gc0308.o
 obj-$(CONFIG_VIDEO_GC2145) += gc2145.o
+obj-$(CONFIG_VIDEO_GT97XX) += gt97xx.o
 obj-$(CONFIG_VIDEO_HI556) += hi556.o
 obj-$(CONFIG_VIDEO_HI846) += hi846.o
 obj-$(CONFIG_VIDEO_HI847) += hi847.o
diff --git a/drivers/media/i2c/gt97xx.c b/drivers/media/i2c/gt97xx.c
new file mode 100644
index 000000000000..ccae190ffba6
--- /dev/null
+++ b/drivers/media/i2c/gt97xx.c
@@ -0,0 +1,436 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for Giantec gt97xx VCM lens device
+ *
+ * Copyright 2024 MediaTek
+ *
+ * Zhi Mao <zhi.mao@xxxxxxxxxxxx>
+ */
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/container_of.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/mod_devicetable.h>
+#include <linux/pm_runtime.h>
+#include <linux/property.h>
+#include <linux/regulator/consumer.h>
+#include <linux/types.h>
+#include <linux/units.h>
+
+#include <media/v4l2-cci.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-subdev.h>
+
+/* gt97xx chip info register and name */
+#define GT97XX_IC_INFO_REG CCI_REG8(0x00)
+#define GT9768_ID 0xE9
+#define GT9769_ID 0xE1
+#define GT97XX_NAME "gt97xx"
+
+/*
+ * Ring control and Power control register
+ * Bit[1] RING_EN
+ * 0: Direct mode
+ * 1: AAC mode (ringing control mode)
+ * Bit[0] PD
+ * 0: Normal operation mode
+ * 1: Power down mode
+ * requires waiting time after PD reset takes place.
+ */
+#define GT97XX_RING_PD_CONTROL_REG CCI_REG8(0x02)
+#define GT97XX_PD_MODE_OFF 0x00
+#define GT97XX_PD_MODE_EN BIT(0)
+#define GT97XX_AAC_MODE_EN BIT(1)
+
+/*
+ * DAC is a 10bit address to control the VCM position.
+ * DAC_MSB: D[9:8] (ADD: 0x03)
+ * DAC_LSB: D[7:0] (ADD: 0x04)
+ */
+#define GT97XX_DAC_ADDR_REG CCI_REG16(0x03)
+
+#define GT97XX_MOVE_STEPS 16
+#define GT97XX_MAX_FOCUS_POS (BIT(10) - 1)
+
+#define GT97XX_SLEEP_US (1 * USEC_PER_MSEC)
+
+enum vcm_giantec_reg_desc {
+	GT_IC_INFO_REG,
+	GT_RING_PD_CONTROL_REG,
+	GT_DAC_ADDR_REG,
+	GT_MAX_REG
+};
+
+struct vcm_giantec_of_data {
+	unsigned int id;
+	unsigned int regs[GT_MAX_REG];
+};
+
+static const char *const gt97xx_supply_names[] = {
+	"vin",
+	"vdd",
+};
+
+/* gt97xx device structure */
+struct gt97xx {
+	struct v4l2_subdev sd;
+
+	struct regulator_bulk_data supplies[ARRAY_SIZE(gt97xx_supply_names)];
+
+	struct v4l2_ctrl_handler ctrls;
+	struct v4l2_ctrl *focus;
+
+	struct regmap *regmap;
+
+	const struct vcm_giantec_of_data *chip;
+};
+
+static inline struct gt97xx *sd_to_gt97xx(struct v4l2_subdev *subdev)
+{
+	return container_of(subdev, struct gt97xx, sd);
+}
+
+struct regval_list {
+	u8 reg_num;
+	u8 value;
+};
+
+static int gt97xx_set_dac(struct gt97xx *gt97xx, u16 val)
+{
+	/* Write VCM position to registers */
+	return cci_write(gt97xx->regmap,
+			 gt97xx->chip->regs[GT_DAC_ADDR_REG], val, NULL);
+}
+
+static int gt97xx_identify_module(struct gt97xx *gt97xx)
+{
+	int ret;
+	u64 ic_id;
+	struct i2c_client *client = v4l2_get_subdevdata(&gt97xx->sd);
+
+	ret = cci_read(gt97xx->regmap, gt97xx->chip->regs[GT_IC_INFO_REG],
+		       &ic_id, NULL);
+	if (ret < 0)
+		return ret;
+
+	if (ic_id != gt97xx->chip->id) {
+		dev_err(&client->dev, "chip id mismatch: 0x%x!=0x%llx",
+			gt97xx->chip->id, ic_id);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int gt97xx_init(struct gt97xx *gt97xx)
+{
+	int ret, val;
+
+	ret = gt97xx_identify_module(gt97xx);
+	if (ret < 0)
+		return ret;
+
+	/* Reset PD_CONTROL */
+	ret = cci_write(gt97xx->regmap,
+			gt97xx->chip->regs[GT_RING_PD_CONTROL_REG],
+			GT97XX_PD_MODE_OFF, NULL);
+	if (ret < 0)
+		return ret;
+
+	/* Need waiting delay time after PD reset */
+	fsleep(GT97XX_SLEEP_US);
+
+	/* Enable ACC mode */
+	ret = cci_write(gt97xx->regmap,
+			gt97xx->chip->regs[GT_RING_PD_CONTROL_REG],
+			GT97XX_AAC_MODE_EN, NULL);
+	if (ret < 0)
+		return ret;
+
+	for (val = gt97xx->focus->val % GT97XX_MOVE_STEPS;
+	     val <= gt97xx->focus->val; val += GT97XX_MOVE_STEPS) {
+		ret = gt97xx_set_dac(gt97xx, val);
+		if (ret)
+			return ret;
+
+		fsleep(GT97XX_SLEEP_US);
+	}
+
+	return 0;
+}
+
+static int gt97xx_release(struct gt97xx *gt97xx)
+{
+	int ret, val;
+
+	val = round_down(gt97xx->focus->val, GT97XX_MOVE_STEPS);
+	for (; val >= 0; val -= GT97XX_MOVE_STEPS) {
+		ret = gt97xx_set_dac(gt97xx, val);
+		if (ret)
+			return ret;
+
+		fsleep(GT97XX_SLEEP_US);
+	}
+
+	return 0;
+}
+
+static int gt97xx_power_on(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct gt97xx *gt97xx = sd_to_gt97xx(sd);
+	int ret;
+
+	ret = regulator_bulk_enable(ARRAY_SIZE(gt97xx_supply_names),
+				    gt97xx->supplies);
+	if (ret < 0)
+		dev_err(dev, "failed to enable regulators\n");
+
+	return ret;
+}
+
+static int gt97xx_power_off(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct gt97xx *gt97xx = sd_to_gt97xx(sd);
+	int ret;
+
+	ret = regulator_bulk_disable(ARRAY_SIZE(gt97xx_supply_names),
+				     gt97xx->supplies);
+	if (ret < 0)
+		dev_err(dev, "failed to disable regulators\n");
+
+	return ret;
+}
+
+static int gt97xx_runtime_suspend(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct gt97xx *gt97xx = sd_to_gt97xx(sd);
+
+	gt97xx_release(gt97xx);
+	gt97xx_power_off(dev);
+
+	return 0;
+}
+
+static int gt97xx_runtime_resume(struct device *dev)
+{
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
+	struct gt97xx *gt97xx = sd_to_gt97xx(sd);
+	int ret;
+
+	ret = gt97xx_power_on(dev);
+	if (ret < 0) {
+		dev_err(dev, "failed to power_on\n");
+		return ret;
+	}
+
+	/* Need waited before sending I2C commands after power-up */
+	fsleep(GT97XX_SLEEP_US);
+
+	ret = gt97xx_init(gt97xx);
+	if (ret < 0)
+		goto disable_power;
+
+	return 0;
+
+disable_power:
+	gt97xx_power_off(dev);
+
+	return ret;
+}
+
+static int gt97xx_set_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct gt97xx *gt97xx =
+		container_of(ctrl->handler, struct gt97xx, ctrls);
+
+	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
+		return gt97xx_set_dac(gt97xx, ctrl->val);
+
+	return 0;
+}
+
+static const struct v4l2_ctrl_ops gt97xx_ctrl_ops = {
+	.s_ctrl = gt97xx_set_ctrl,
+};
+
+static int gt97xx_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	return pm_runtime_resume_and_get(sd->dev);
+}
+
+static int gt97xx_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	return pm_runtime_put(sd->dev);
+}
+
+static const struct v4l2_subdev_internal_ops gt97xx_int_ops = {
+	.open = gt97xx_open,
+	.close = gt97xx_close,
+};
+
+static const struct v4l2_subdev_core_ops gt97xx_core_ops = {
+	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
+	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
+};
+
+static const struct v4l2_subdev_ops gt97xx_ops = {
+	.core = &gt97xx_core_ops,
+};
+
+static int gt97xx_init_controls(struct gt97xx *gt97xx)
+{
+	struct v4l2_ctrl_handler *hdl = &gt97xx->ctrls;
+	const struct v4l2_ctrl_ops *ops = &gt97xx_ctrl_ops;
+
+	v4l2_ctrl_handler_init(hdl, 1);
+
+	gt97xx->focus = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, 0,
+					  GT97XX_MAX_FOCUS_POS,
+					  1, 0);
+
+	if (hdl->error)
+		return hdl->error;
+
+	gt97xx->sd.ctrl_handler = hdl;
+
+	return 0;
+}
+
+static int gt97xx_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct gt97xx *gt97xx;
+	unsigned int i;
+	int ret;
+
+	gt97xx = devm_kzalloc(dev, sizeof(*gt97xx), GFP_KERNEL);
+	if (!gt97xx)
+		return -ENOMEM;
+
+	gt97xx->regmap = devm_cci_regmap_init_i2c(client, 8);
+	if (IS_ERR(gt97xx->regmap))
+		return dev_err_probe(dev, PTR_ERR(gt97xx->regmap),
+				     "failed to init CCI\n");
+
+	/* Initialize subdev */
+	v4l2_i2c_subdev_init(&gt97xx->sd, client, &gt97xx_ops);
+
+	gt97xx->chip = device_get_match_data(dev);
+
+	for (i = 0; i < ARRAY_SIZE(gt97xx_supply_names); i++)
+		gt97xx->supplies[i].supply = gt97xx_supply_names[i];
+
+	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(gt97xx_supply_names),
+				      gt97xx->supplies);
+	if (ret < 0)
+		return dev_err_probe(dev, ret,
+				     "failed to get regulators\n");
+
+	/* Initialize controls */
+	ret = gt97xx_init_controls(gt97xx);
+	if (ret)
+		goto err_free_handler;
+
+	/* Initialize subdev */
+	gt97xx->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	gt97xx->sd.internal_ops = &gt97xx_int_ops;
+	gt97xx->sd.entity.function = MEDIA_ENT_F_LENS;
+
+	ret = media_entity_pads_init(&gt97xx->sd.entity, 0, NULL);
+	if (ret < 0)
+		goto err_free_handler;
+
+	/* Power on and initialize hardware */
+	ret = gt97xx_runtime_resume(dev);
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to power on\n");
+		goto err_clean_entity;
+	}
+
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+	pm_runtime_set_autosuspend_delay(dev, 1000);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_idle(dev);
+
+	ret = v4l2_async_register_subdev(&gt97xx->sd);
+	if (ret < 0) {
+		dev_err_probe(dev, ret, "failed to register V4L2 subdev\n");
+		goto err_power_off;
+	}
+
+	return 0;
+
+err_power_off:
+	pm_runtime_disable(dev);
+err_clean_entity:
+	media_entity_cleanup(&gt97xx->sd.entity);
+err_free_handler:
+	v4l2_ctrl_handler_free(&gt97xx->ctrls);
+
+	return ret;
+}
+
+static void gt97xx_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct gt97xx *gt97xx = sd_to_gt97xx(sd);
+
+	v4l2_async_unregister_subdev(&gt97xx->sd);
+	v4l2_ctrl_handler_free(&gt97xx->ctrls);
+	media_entity_cleanup(&gt97xx->sd.entity);
+	pm_runtime_disable(&client->dev);
+	if (!pm_runtime_status_suspended(&client->dev))
+		gt97xx_runtime_suspend(&client->dev);
+	pm_runtime_set_suspended(&client->dev);
+}
+
+static DEFINE_RUNTIME_DEV_PM_OPS(gt97xx_pm_ops,
+				 gt97xx_runtime_suspend,
+				 gt97xx_runtime_resume,
+				 NULL);
+
+static const struct vcm_giantec_of_data gt9768_data = {
+	.id = GT9768_ID,
+	.regs[GT_IC_INFO_REG] = GT97XX_IC_INFO_REG,
+	.regs[GT_RING_PD_CONTROL_REG] = GT97XX_RING_PD_CONTROL_REG,
+	.regs[GT_DAC_ADDR_REG] = GT97XX_DAC_ADDR_REG,
+};
+
+static const struct vcm_giantec_of_data gt9769_data = {
+	.id = GT9769_ID,
+	.regs[GT_IC_INFO_REG] = GT97XX_IC_INFO_REG,
+	.regs[GT_RING_PD_CONTROL_REG] = GT97XX_RING_PD_CONTROL_REG,
+	.regs[GT_DAC_ADDR_REG] = GT97XX_DAC_ADDR_REG,
+};
+
+static const struct of_device_id gt97xx_of_table[] = {
+	{ .compatible = "giantec,gt9768", .data = &gt9768_data },
+	{ .compatible = "giantec,gt9769", .data = &gt9769_data },
+	{}
+};
+MODULE_DEVICE_TABLE(of, gt97xx_of_table);
+
+static struct i2c_driver gt97xx_i2c_driver = {
+	.driver = {
+		.name = GT97XX_NAME,
+		.pm = pm_ptr(&gt97xx_pm_ops),
+		.of_match_table = gt97xx_of_table,
+	},
+	.probe = gt97xx_probe,
+	.remove = gt97xx_remove,
+};
+module_i2c_driver(gt97xx_i2c_driver);
+
+MODULE_AUTHOR("Zhi Mao <zhi.mao@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("GT97xx VCM driver");
+MODULE_LICENSE("GPL");
-- 
2.25.1