Hi Dongchun,
On Sun, May 03, 2020 at 12:17:27AM +0800, Dongchun Zhu wrote:
> Add a V4L2 sub-device driver for DW9768 voice coil motor, providing
> control to set the desired focus via IIC serial interface.
>
> Signed-off-by: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx>
> ---
> MAINTAINERS | 1 +
> drivers/media/i2c/Kconfig | 11 ++
> drivers/media/i2c/Makefile | 1 +
> drivers/media/i2c/dw9768.c | 440 +++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 453 insertions(+)
> create mode 100644 drivers/media/i2c/dw9768.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 8d72c41..c92dc99 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -5157,6 +5157,7 @@ L: linux-media@xxxxxxxxxxxxxxx
> S: Maintained
> T: git git://linuxtv.org/media_tree.git
> F: Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml
> +F: drivers/media/i2c/dw9768.c
>
> DONGWOON DW9807 LENS VOICE COIL DRIVER
> M: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 125d596..6a3f9da 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -1040,6 +1040,17 @@ config VIDEO_DW9714
> capability. 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 && MEDIA_CONTROLLER
> + depends on VIDEO_V4L2_SUBDEV_API
Please check how this works in the media tree master branch now --- it's
largely select based.
In general the patch seems fine to me, but please see the other comments
below, too.
> + depends on PM
> + help
> + This is a driver for the DW9768 camera lens voice coil.
> + DW9768 is a 10 bit DAC with 100mA output current sink
> + capability. This is designed for linear control of
> + voice coil motors, controlled via I2C serial interface.
> +
> config VIDEO_DW9807_VCM
> tristate "DW9807 lens voice coil support"
> depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index 77bf7d0..4057476 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-$(CONFIG_VIDEO_DW9768) += dw9768.o
> obj-$(CONFIG_VIDEO_DW9807_VCM) += dw9807-vcm.o
> obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o
> obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o
> diff --git a/drivers/media/i2c/dw9768.c b/drivers/media/i2c/dw9768.c
> new file mode 100644
> index 0000000..dd68534
> --- /dev/null
> +++ b/drivers/media/i2c/dw9768.c
> @@ -0,0 +1,440 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2020 MediaTek Inc.
> +
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
> +#include <media/v4l2-async.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-subdev.h>
> +
> +#define DW9768_NAME "dw9768"
> +#define DW9768_MAX_FOCUS_POS (1024 - 1)
> +/*
> + * This sets the minimum granularity for the focus positions.
> + * A value of 1 gives maximum accuracy for a desired focus position
> + */
> +#define DW9768_FOCUS_STEPS 1
> +
> +/*
> + * 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
> + * DW9768 requires waiting time of Topr after PD reset takes place.
> + */
> +#define DW9768_RING_PD_CONTROL_REG 0x02
> +#define DW9768_PD_MODE_OFF 0x00
> +#define DW9768_PD_MODE_EN BIT(0)
> +#define DW9768_AAC_MODE_EN BIT(1)
> +
> +/*
> + * DW9768 separates two registers to control the VCM position.
> + * One for MSB value, another is LSB value.
> + * DAC_MSB: D[9:8] (ADD: 0x03)
> + * DAC_LSB: D[7:0] (ADD: 0x04)
> + * D[9:0] DAC data input: positive output current = D[9:0] / 1023 * 100[mA]
> + */
> +#define DW9768_MSB_ADDR 0x03
> +#define DW9768_LSB_ADDR 0x04
> +#define DW9768_STATUS_ADDR 0x05
> +
> +/*
> + * AAC mode control & prescale register
> + * Bit[7:5] Namely AC[2:0], decide the VCM mode and operation time.
> + * 000 Direct(default)
> + * 001 AAC2 0.48xTvib
> + * 010 AAC3 0.70xTvib
> + * 011 AAC4 0.75xTvib
> + * 100 Reserved
> + * 101 AAC8 1.13xTvib
> + * 110 Reserved
> + * 111 Reserved
> + * Bit[2:0] Namely PRESC[2:0], set the internal clock dividing rate as follow.
> + * 000 2
> + * 001 1(default)
> + * 010 1/2
> + * 011 1/4
> + * 100 8
> + * 101 4
> + * 110 Reserved
> + * 111 Reserved
> + */
> +#define DW9768_AAC_PRESC_REG 0x06
> +#define DW9768_AAC3_SELECT_DIVIDING_RATE_1 0x41
I guess we can start with these values. But I can't think of another option
than putting them into DT if there are differences between what hardware
platforms require.
> +
> +/*
> + * VCM period of vibration register
> + * Bit[5:0] Defined as VCM rising periodic time (Tvib) together with PRESC[2:0]
> + * Tvib = (6.3ms + AACT[5:0] * 0.1ms) * Dividing Rate
> + * Dividing Rate is the internal clock dividing rate that is defined at
> + * PRESCALE register (ADD: 0x06)
> + */
> +#define DW9768_AAC_TIME_REG 0x07
> +#define DW9768_AACT_CNT 0x39
> +
> +/*
> + * DW9768 requires waiting time (delay time) of t_OPR after power-up,
> + * or in the case of PD reset taking place.
> + */
> +#define DW9768_T_OPR_US 1000
> +
> +/*
> + * This acts as the minimum granularity of lens movement.
> + * Keep this value power of 2, so the control steps can be
> + * uniformly adjusted for gradual lens movement, with desired
> + * number of control steps.
> + */
> +#define DW9768_MOVE_STEPS 16
> +
> +/*
> + * DW9768_AAC_PRESC_REG & DW9768_AAC_TIME_REG determine VCM operation time.
> + * If DW9768_AAC_PRESC_REG is 0x41, and DW9768_AAC_TIME_REG is 0x39, VCM mode
> + * would be AAC3, Operation Time would be 0.70xTvib, that is 8.40ms.
> + */
> +#define DW9768_MOVE_DELAY_US 8400
> +#define DW9768_STABLE_TIME_US 20000
> +
> +static const char * const dw9768_supply_names[] = {
> + "vin", /* I2C I/O interface power */
> + "vdd", /* VCM power */
> +};
> +
> +/* dw9768 device structure */
> +struct dw9768 {
> + struct regulator_bulk_data supplies[ARRAY_SIZE(dw9768_supply_names)];
> + struct v4l2_ctrl_handler ctrls;
> + struct v4l2_ctrl *focus;
> + struct v4l2_subdev sd;
> +};
> +
> +static inline struct dw9768 *to_dw9768(struct v4l2_ctrl *ctrl)
> +{
> + return container_of(ctrl->handler, struct dw9768, ctrls);
> +}
This is used in a single place. I'd just use container_of() directly there.
> +
> +static inline struct dw9768 *sd_to_dw9768(struct v4l2_subdev *subdev)
> +{
> + return container_of(subdev, struct dw9768, sd);
> +}
> +
> +struct regval_list {
> + u8 reg_num;
> + u8 value;
> +};
> +
> +static const struct regval_list dw9768_init_regs[] = {
> + {DW9768_RING_PD_CONTROL_REG, DW9768_AAC_MODE_EN},
> + {DW9768_AAC_PRESC_REG, DW9768_AAC3_SELECT_DIVIDING_RATE_1},
> + {DW9768_AAC_TIME_REG, DW9768_AACT_CNT},
> +};
> +
> +static int dw9768_write_array(struct dw9768 *dw9768,
> + const struct regval_list *vals, size_t len)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> + unsigned int i;
> + int ret;
> +
> + for (i = 0; i < len; i++) {
> + ret = i2c_smbus_write_byte_data(client, vals[i].reg_num,
> + vals[i].value);
> + if (ret < 0)
> + return ret;
> + }
> + return 0;
> +}
> +
> +static int dw9768_set_dac(struct dw9768 *dw9768, u16 val)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +
> + /* Write VCM position to registers */
> + return i2c_smbus_write_word_swapped(client, DW9768_MSB_ADDR, val);
> +}
> +
> +static int dw9768_init(struct dw9768 *dw9768)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> + int ret, val;
> +
> + /* Reset DW9768_RING_PD_CONTROL_REG to default status 0x00 */
> + ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
> + DW9768_PD_MODE_OFF);
> + if (ret < 0)
> + return ret;
> +
> + /*
> + * DW9769 requires waiting delay time of t_OPR
> + * after PD reset takes place.
> + */
> + usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
> +
> + ret = dw9768_write_array(dw9768, dw9768_init_regs,
> + ARRAY_SIZE(dw9768_init_regs));
> + if (ret)
> + return ret;
> +
> + for (val = dw9768->focus->val % DW9768_MOVE_STEPS;
> + val <= dw9768->focus->val;
> + val += DW9768_MOVE_STEPS) {
> + ret = dw9768_set_dac(dw9768, val);
> + if (ret) {
> + dev_err(&client->dev, "%s I2C failure: %d",
> + __func__, ret);
> + return ret;
> + }
> + usleep_range(DW9768_MOVE_DELAY_US,
> + DW9768_MOVE_DELAY_US + 1000);
> + }
> +
> + return 0;
> +}
> +
> +static int dw9768_release(struct dw9768 *dw9768)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> + int ret, val;
> +
> + val = round_down(dw9768->focus->val, DW9768_MOVE_STEPS);
> + for ( ; val >= 0; val -= DW9768_MOVE_STEPS) {
> + ret = dw9768_set_dac(dw9768, val);
> + if (ret) {
> + dev_err(&client->dev, "I2C write fail: %d", ret);
> + return ret;
> + }
> + usleep_range(DW9768_MOVE_DELAY_US, DW9768_MOVE_DELAY_US + 1000);
> + }
> +
> + /*
> + * Wait for the motor to stabilize after the last movement
> + * to prevent the motor from shaking.
> + */
> + usleep_range(DW9768_STABLE_TIME_US - DW9768_MOVE_DELAY_US,
> + DW9768_STABLE_TIME_US - DW9768_MOVE_DELAY_US + 1000);
> +
> + ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
> + DW9768_PD_MODE_EN);
> + if (ret < 0)
> + return ret;
> +
> + /*
> + * DW9769 requires waiting delay time of t_OPR
> + * after PD reset takes place.
> + */
> + usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused dw9768_runtime_suspend(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct dw9768 *dw9768 = sd_to_dw9768(sd);
> +
> + dw9768_release(dw9768);
> + regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
> + dw9768->supplies);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused dw9768_runtime_resume(struct device *dev)
> +{
> + struct i2c_client *client = to_i2c_client(dev);
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct dw9768 *dw9768 = sd_to_dw9768(sd);
> + int ret;
> +
> + ret = regulator_bulk_enable(ARRAY_SIZE(dw9768_supply_names),
> + dw9768->supplies);
> + if (ret < 0) {
> + dev_err(dev, "failed to enable regulators\n");
> + return ret;
> + }
> +
> + /*
> + * The datasheet refers to t_OPR that needs to be waited before sending
> + * I2C commands after power-up.
> + */
> + usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
> +
> + ret = dw9768_init(dw9768);
> + if (ret < 0)
> + goto disable_regulator;
> +
> + return 0;
> +
> +disable_regulator:
> + regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
> + dw9768->supplies);
> +
> + return ret;
> +}
> +
> +static int dw9768_set_ctrl(struct v4l2_ctrl *ctrl)
> +{
> + struct dw9768 *dw9768 = to_dw9768(ctrl);
> +
> + if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
> + return dw9768_set_dac(dw9768, ctrl->val);
> +
> + return 0;
> +}
> +
> +static const struct v4l2_ctrl_ops dw9768_ctrl_ops = {
> + .s_ctrl = dw9768_set_ctrl,
> +};
> +
> +static int dw9768_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> + int ret;
> +
> + ret = pm_runtime_get_sync(sd->dev);
> + if (ret < 0) {
> + pm_runtime_put_noidle(sd->dev);
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static int dw9768_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> + pm_runtime_put(sd->dev);
> +
> + return 0;
> +}
> +
> +static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
> + .open = dw9768_open,
> + .close = dw9768_close,
> +};
> +
> +static const struct v4l2_subdev_ops dw9768_ops = { };
> +
> +static int dw9768_init_controls(struct dw9768 *dw9768)
> +{
> + struct v4l2_ctrl_handler *hdl = &dw9768->ctrls;
> + const struct v4l2_ctrl_ops *ops = &dw9768_ctrl_ops;
> +
> + v4l2_ctrl_handler_init(hdl, 1);
> +
> + dw9768->focus = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, 0,
> + DW9768_MAX_FOCUS_POS,
> + DW9768_FOCUS_STEPS, 0);
> +
> + if (hdl->error)
> + return hdl->error;
> +
> + dw9768->sd.ctrl_handler = hdl;
> +
> + return 0;
> +}
> +
> +static int dw9768_probe(struct i2c_client *client)
> +{
> + struct device *dev = &client->dev;
> + struct dw9768 *dw9768;
> + unsigned int i;
> + int ret;
> +
> + dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
> + if (!dw9768)
> + return -ENOMEM;
> +
> + v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
> +
> + for (i = 0; i < ARRAY_SIZE(dw9768_supply_names); i++)
> + dw9768->supplies[i].supply = dw9768_supply_names[i];
> +
> + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(dw9768_supply_names),
> + dw9768->supplies);
> + if (ret) {
> + dev_err(dev, "failed to get regulators\n");
> + return ret;
> + }
> +
> + ret = dw9768_init_controls(dw9768);
> + if (ret)
> + goto entity_cleanup;
> +
> + dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> + dw9768->sd.internal_ops = &dw9768_int_ops;
> +
> + ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
> + if (ret < 0)
> + goto entity_cleanup;
> +
> + dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
> +
> + pm_runtime_enable(dev);
> + if (!pm_runtime_enabled(dev)) {
> + ret = dw9768_runtime_resume(dev);
> + if (ret < 0) {
> + dev_err(dev, "failed to power on: %d\n", ret);
> + goto entity_cleanup;
> + }
> + }
> +
> + ret = v4l2_async_register_subdev(&dw9768->sd);
> + if (ret < 0)
> + goto entity_cleanup;
> +
> + return 0;
> +
> +entity_cleanup:
> + v4l2_ctrl_handler_free(&dw9768->ctrls);
> + media_entity_cleanup(&dw9768->sd.entity);
> + return ret;
> +}
> +
> +static int dw9768_remove(struct i2c_client *client)
> +{
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct dw9768 *dw9768 = sd_to_dw9768(sd);
> +
> + pm_runtime_disable(&client->dev);
> + v4l2_async_unregister_subdev(&dw9768->sd);
> + v4l2_ctrl_handler_free(&dw9768->ctrls);
> + media_entity_cleanup(&dw9768->sd.entity);
> + if (!pm_runtime_status_suspended(&client->dev))
> + dw9768_runtime_suspend(&client->dev);
> + pm_runtime_set_suspended(&client->dev);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id dw9768_of_table[] = {
> + { .compatible = "dongwoon,dw9768" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, dw9768_of_table);
> +
> +static const struct dev_pm_ops dw9768_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> + pm_runtime_force_resume)
> + SET_RUNTIME_PM_OPS(dw9768_runtime_suspend, dw9768_runtime_resume, NULL)
> +};
> +
> +static struct i2c_driver dw9768_i2c_driver = {
> + .driver = {
> + .name = DW9768_NAME,
> + .pm = &dw9768_pm_ops,
> + .of_match_table = dw9768_of_table,
> + },
> + .probe_new = dw9768_probe,
> + .remove = dw9768_remove,
> +};
> +module_i2c_driver(dw9768_i2c_driver);
> +
> +MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx>");
> +MODULE_DESCRIPTION("DW9768 VCM driver");
> +MODULE_LICENSE("GPL v2");
--
Kind regards,
Sakari Ailus
