diff mbox series

[v3,14/18] media: i2c: Add driver for DW9719 VCM

Message ID 20230705213010.390849-15-hdegoede@redhat.com
State New
Headers show
Series media: ipu-bridge: Shared with atomisp, rework VCM instantiation | expand

Commit Message

Hans de Goede July 5, 2023, 9:30 p.m. UTC
From: 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>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v3 (Hans de Goede)
- New patch in v3 of this series based on Dan Scally's initial
  DW9719 upstream submission:
  https://lore.kernel.org/all/20211128232115.38833-1-djrscally@gmail.com/
- Drop hack to enable "vsio" regulator, this is no longer necessary
  now that there is a device-link making the VCM a runtime-pm consumer
  of the sensor
- Add checking of device-properties for sac-mode and vcm-freq,
  as requested by Sakari, this is done similar to the dw9768:
  Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml
  Note no devicetree binding doc is added since currently only
  i2c_device_id enumeration (instantiated by IPU bridge) is
  supported
---
 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

Comments

Sakari Ailus July 6, 2023, 7:47 a.m. UTC | #1
Hi Hans,

Thanks for the update.

On Wed, Jul 05, 2023 at 11:30:06PM +0200, Hans de Goede wrote:
> From: 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>
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
> Changes in v3 (Hans de Goede)
> - New patch in v3 of this series based on Dan Scally's initial
>   DW9719 upstream submission:
>   https://lore.kernel.org/all/20211128232115.38833-1-djrscally@gmail.com/
> - Drop hack to enable "vsio" regulator, this is no longer necessary
>   now that there is a device-link making the VCM a runtime-pm consumer
>   of the sensor
> - Add checking of device-properties for sac-mode and vcm-freq,
>   as requested by Sakari, this is done similar to the dw9768:
>   Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml
>   Note no devicetree binding doc is added since currently only
>   i2c_device_id enumeration (instantiated by IPU bridge) is
>   supported
> ---
>  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 494682dd437f..cf8e799f6ea2 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6266,6 +6266,13 @@ T:	git git://linuxtv.org/media_tree.git
>  F:	Documentation/devicetree/bindings/media/i2c/dongwoon,dw9714.yaml
>  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
>  L:	linux-media@vger.kernel.org
>  S:	Orphan
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 26dc365365d8..4864f1df3c7a 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -875,6 +875,17 @@ 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_DEV
> +	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_DEV
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index d175a2e2fb19..745f8d07e649 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -32,6 +32,7 @@ obj-$(CONFIG_VIDEO_DS90UB913) += ds90ub913.o
>  obj-$(CONFIG_VIDEO_DS90UB953) += ds90ub953.o
>  obj-$(CONFIG_VIDEO_DS90UB960) += ds90ub960.o
>  obj-$(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_ET8EK8) += et8ek8/
> diff --git a/drivers/media/i2c/dw9719.c b/drivers/media/i2c/dw9719.c
> new file mode 100644
> index 000000000000..7b83ae102131
> --- /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_SAC_SHIFT		4
> +#define DW9719_MODE_SAC3		4
> +
> +#define DW9719_DEFAULT_VCM_FREQ		0x60
> +
> +#define DW9719_ENABLE_RINGING		0x02
> +
> +#define to_dw9719_device(x) container_of(x, struct dw9719_device, sd)
> +
> +struct dw9719_device {
> +	struct device *dev;
> +	struct i2c_client *client;
> +	struct regulator *regulator;
> +	struct v4l2_subdev sd;
> +	u32 sac_mode;
> +	u32 vcm_freq;
> +
> +	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;
> +}

Seems like a use case for the new CCI register access framework. :-)

Doesn't need to be on this set, though: there are lot of other drivers that
could be converted as well.

> +
> +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_disable(dw9719->regulator);
> +}
> +
> +static int dw9719_power_up(struct dw9719_device *dw9719)
> +{
> +	int ret;
> +
> +	ret = regulator_enable(dw9719->regulator);
> +	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->sac_mode << DW9719_MODE_SAC_SHIFT);
> +	if (ret < 0)
> +		goto fail_powerdown;
> +
> +	ret = dw9719_i2c_wr8(dw9719->client, DW9719_VCM_FREQ, dw9719->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;

This check can be dropped.

> +
> +	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->sac_mode = DW9719_MODE_SAC3;
> +	dw9719->vcm_freq = DW9719_DEFAULT_VCM_FREQ;
> +
> +	/* Optional indication of SAC mode select */
> +	device_property_read_u32(&client->dev, "dongwoon,sac-mode",
> +				 &dw9719->sac_mode);
> +
> +	/* Optional indication of VCM frequency */
> +	device_property_read_u32(&client->dev, "dongwoon,vcm-freq",
> +				 &dw9719->vcm_freq);
> +
> +	dw9719->regulator = devm_regulator_get(&client->dev, "vdd");
> +	if (IS_ERR(dw9719->regulator))
> +		return dev_err_probe(&client->dev, PTR_ERR(dw9719->regulator),
> +				     "getting regulator\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 void 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);

No need for such a long line.

> +
> +	pm_runtime_disable(&client->dev);
> +	v4l2_async_unregister_subdev(sd);
> +	v4l2_ctrl_handler_free(&dw9719->ctrls.handler);
> +	media_entity_cleanup(&dw9719->sd.entity);

Missing call to dw9719_power_down().

I can address these while applying (assuming that's all in terms of changes
needed).

> +}
> +
> +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");
Andy Shevchenko July 6, 2023, 9:14 a.m. UTC | #2
On Thu, Jul 06, 2023 at 07:47:38AM +0000, Sakari Ailus wrote:
> On Wed, Jul 05, 2023 at 11:30:06PM +0200, Hans de Goede wrote:

...

> > +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;
> 
> This check can be dropped.

The obvious question why that API returns int instead of void?

> > +	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;

	return 0;

?

> > +err_free_handler:
> > +	v4l2_ctrl_handler_free(&dw9719->ctrls.handler);
> > +	return ret;
> > +}
Andy Shevchenko July 6, 2023, 10:06 a.m. UTC | #3
On Wed, Jul 05, 2023 at 11:30:06PM +0200, Hans de Goede wrote:
> From: 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.

...

> +/*
> + * Based on linux/modules/camera/drivers/media/i2c/imx/dw9719.c in this repo:

Sakari, also long line? :-)

> + * https://github.com/ZenfoneArea/android_kernel_asus_zenfone5
> + */

...

> +#include <asm/unaligned.h>

Usually we include headers from generic to particular / private,
hence asm/* usually goes after linux/*.

> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/types.h>

...

> +#define DW9719_CTRL_DELAY_US	1000

USEC_PER_MSEC ?

...

> +#define DELAY_MAX_PER_STEP_NS	(1000000 * 1023)

NSEC_PER_MSEC ?

...

> +#define DW9719_DEFAULT_VCM_FREQ		0x60

Any comment what this value means in Hz?

...

> +#define to_dw9719_device(x) container_of(x, struct dw9719_device, sd)

You can make this no-op at compile time by...

...

> +struct dw9719_device {
> +	struct device *dev;
> +	struct i2c_client *client;
> +	struct regulator *regulator;

> +	struct v4l2_subdev sd;

...having this to be the first member in the structure.

However bloat-o-meter can show grow of the code in case the dev is used more
often. The rule of thumb is to combine two aspects:
- frequency of usage (hence pointer arithmetics);
- hot path vs. slow path (hence importance of the lesser code).

> +	u32 sac_mode;
> +	u32 vcm_freq;
> +
> +	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;

	sizeof(buf[0])
	&buf[0]

looks more explicit.

> +	msg[1].addr = client->addr;
> +	msg[1].flags = I2C_M_RD;
> +	msg[1].len = 1;
> +	msg[1].buf = &buf[1];

Ditto.

> +	*val = 0;
> +
> +	ret = i2c_transfer(client->adapter, msg, 2);

ARRAY_SIZE()

> +	if (ret < 0)
> +		return ret;
> +
> +	*val = buf[1];
> +
> +	return 0;
> +}

But as Sakari said this perhaps could go into CCI library.

...

> +	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 -ENXIO;

> +	}
> +
> +	return 0;

...

> +	/* Need 100us to transit from SHUTDOWN to STANDBY*/

Missing space.

> +	usleep_range(100, 1000);

Perhaps fsleep() would be better, but I'm fine with either here.

...

> +static int dw9719_t_focus_abs(struct dw9719_device *dw9719, s32 value)
> +{
> +	int ret;

Redundant?

> +	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;

	return _wr16(...);

or can it return positive values?

> +}

...

> +static int __maybe_unused dw9719_suspend(struct device *dev)

Can we use new PM macros instead of __maybe_unused?

> +{
> +	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);

fsleep() ?

> +	}
> +
> +	return dw9719_power_down(dw9719);
> +}

> +static int __maybe_unused dw9719_resume(struct device *dev)
> +{

As per above function.

...

> +err_power_down:

In one functions you use err_ in another fail_, be consistent.

> +	dw9719_power_down(dw9719);
> +	return ret;
> +}

...

> +	dw9719->regulator = devm_regulator_get(&client->dev, "vdd");
> +	if (IS_ERR(dw9719->regulator))
> +		return dev_err_probe(&client->dev, PTR_ERR(dw9719->regulator),

With

	struct device *dev = &client->dev;

code may look neater.

> +				     "getting regulator\n");
Hans de Goede July 6, 2023, 2:34 p.m. UTC | #4
Hi,

On 7/6/23 12:06, Andy Shevchenko wrote:
> On Wed, Jul 05, 2023 at 11:30:06PM +0200, Hans de Goede wrote:
>> From: 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.
> 
> ...
> 
>> +/*
>> + * Based on linux/modules/camera/drivers/media/i2c/imx/dw9719.c in this repo:
> 
> Sakari, also long line? :-)

Nope, this is 79 chars.

> 
>> + * https://github.com/ZenfoneArea/android_kernel_asus_zenfone5
>> + */
> 
> ...
> 
>> +#include <asm/unaligned.h>
> 
> Usually we include headers from generic to particular / private,
> hence asm/* usually goes after linux/*.

Ack (gone after switching to CCI helpers in next version).

>> +#include <linux/delay.h>
>> +#include <linux/i2c.h>
>> +#include <linux/pm_runtime.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <linux/types.h>
> 
> ...
> 
>> +#define DW9719_CTRL_DELAY_US	1000
> 
> USEC_PER_MSEC ?

I don't see how that helps readability.

> 
> ...
> 
>> +#define DELAY_MAX_PER_STEP_NS	(1000000 * 1023)
> 
> NSEC_PER_MSEC ?

This define is not used so I've dropped it for the next version.

> 
> ...
> 
>> +#define DW9719_DEFAULT_VCM_FREQ		0x60
> 
> Any comment what this value means in Hz?

This comes directly from the Android driver, no idea what this actually means (no datasheet).

> 
> ...
> 
>> +#define to_dw9719_device(x) container_of(x, struct dw9719_device, sd)
> 
> You can make this no-op at compile time by...
> 
> ...
> 
>> +struct dw9719_device {
>> +	struct device *dev;
>> +	struct i2c_client *client;
>> +	struct regulator *regulator;
> 
>> +	struct v4l2_subdev sd;
> 
> ...having this to be the first member in the structure.

Ack.

> However bloat-o-meter can show grow of the code in case the dev is used more
> often. The rule of thumb is to combine two aspects:
> - frequency of usage (hence pointer arithmetics);
> - hot path vs. slow path (hence importance of the lesser code).
> 
>> +	u32 sac_mode;
>> +	u32 vcm_freq;
>> +
>> +	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;
> 
> 	sizeof(buf[0])
> 	&buf[0]
> 
> looks more explicit.
> 
>> +	msg[1].addr = client->addr;
>> +	msg[1].flags = I2C_M_RD;
>> +	msg[1].len = 1;
>> +	msg[1].buf = &buf[1];
> 
> Ditto.
> 
>> +	*val = 0;
>> +
>> +	ret = i2c_transfer(client->adapter, msg, 2);
> 
> ARRAY_SIZE()
> 
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	*val = buf[1];
>> +
>> +	return 0;
>> +}
> 
> But as Sakari said this perhaps could go into CCI library.

Right, this is all gone after switching to the new CCI helpers.



> 
> ...
> 
>> +	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 -ENXIO;
> 
>> +	}
>> +
>> +	return 0;
> 
> ...
> 
>> +	/* Need 100us to transit from SHUTDOWN to STANDBY*/
> 
> Missing space.
> 
>> +	usleep_range(100, 1000);
> 
> Perhaps fsleep() would be better, but I'm fine with either here.

fsleep() indeed is better here.

> 
> ...
> 
>> +static int dw9719_t_focus_abs(struct dw9719_device *dw9719, s32 value)
>> +{
>> +	int ret;
> 
> Redundant?
> 
>> +	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;
> 
> 	return _wr16(...);
> 
> or can it return positive values?

Ack, fixed.

> 
>> +}
> 
> ...
> 
>> +static int __maybe_unused dw9719_suspend(struct device *dev)
> 
> Can we use new PM macros instead of __maybe_unused?

Ack, fixed.

>> +{
>> +	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);
> 
> fsleep() ?

fsleep would expand to:

		usleep_range(DW9719_CTRL_DELAY_US,  2 * DW9719_CTRL_DELAY_US);

making the loop take up to twice as long.


> 
>> +	}
>> +
>> +	return dw9719_power_down(dw9719);
>> +}
> 
>> +static int __maybe_unused dw9719_resume(struct device *dev)
>> +{
> 
> As per above function.
> 
> ...
> 
>> +err_power_down:
> 
> In one functions you use err_ in another fail_, be consistent.

Ack, fixed.

Regards,

Hans
Andy Shevchenko July 6, 2023, 2:47 p.m. UTC | #5
On Thu, Jul 06, 2023 at 04:34:41PM +0200, Hans de Goede wrote:
> On 7/6/23 12:06, Andy Shevchenko wrote:
> > On Wed, Jul 05, 2023 at 11:30:06PM +0200, Hans de Goede wrote:

...

> >> +		usleep_range(DW9719_CTRL_DELAY_US, DW9719_CTRL_DELAY_US + 10);
> > 
> > fsleep() ?
> 
> fsleep would expand to:
> 
> 		usleep_range(DW9719_CTRL_DELAY_US,  2 * DW9719_CTRL_DELAY_US);
> 
> making the loop take up to twice as long.

Is it a problem here? If so, perhaps one line to explain that?

> >> +	}
diff mbox series

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 494682dd437f..cf8e799f6ea2 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6266,6 +6266,13 @@  T:	git git://linuxtv.org/media_tree.git
 F:	Documentation/devicetree/bindings/media/i2c/dongwoon,dw9714.yaml
 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
 L:	linux-media@vger.kernel.org
 S:	Orphan
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 26dc365365d8..4864f1df3c7a 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -875,6 +875,17 @@  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_DEV
+	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_DEV
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index d175a2e2fb19..745f8d07e649 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -32,6 +32,7 @@  obj-$(CONFIG_VIDEO_DS90UB913) += ds90ub913.o
 obj-$(CONFIG_VIDEO_DS90UB953) += ds90ub953.o
 obj-$(CONFIG_VIDEO_DS90UB960) += ds90ub960.o
 obj-$(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_ET8EK8) += et8ek8/
diff --git a/drivers/media/i2c/dw9719.c b/drivers/media/i2c/dw9719.c
new file mode 100644
index 000000000000..7b83ae102131
--- /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_SAC_SHIFT		4
+#define DW9719_MODE_SAC3		4
+
+#define DW9719_DEFAULT_VCM_FREQ		0x60
+
+#define DW9719_ENABLE_RINGING		0x02
+
+#define to_dw9719_device(x) container_of(x, struct dw9719_device, sd)
+
+struct dw9719_device {
+	struct device *dev;
+	struct i2c_client *client;
+	struct regulator *regulator;
+	struct v4l2_subdev sd;
+	u32 sac_mode;
+	u32 vcm_freq;
+
+	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_disable(dw9719->regulator);
+}
+
+static int dw9719_power_up(struct dw9719_device *dw9719)
+{
+	int ret;
+
+	ret = regulator_enable(dw9719->regulator);
+	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->sac_mode << DW9719_MODE_SAC_SHIFT);
+	if (ret < 0)
+		goto fail_powerdown;
+
+	ret = dw9719_i2c_wr8(dw9719->client, DW9719_VCM_FREQ, dw9719->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->sac_mode = DW9719_MODE_SAC3;
+	dw9719->vcm_freq = DW9719_DEFAULT_VCM_FREQ;
+
+	/* Optional indication of SAC mode select */
+	device_property_read_u32(&client->dev, "dongwoon,sac-mode",
+				 &dw9719->sac_mode);
+
+	/* Optional indication of VCM frequency */
+	device_property_read_u32(&client->dev, "dongwoon,vcm-freq",
+				 &dw9719->vcm_freq);
+
+	dw9719->regulator = devm_regulator_get(&client->dev, "vdd");
+	if (IS_ERR(dw9719->regulator))
+		return dev_err_probe(&client->dev, PTR_ERR(dw9719->regulator),
+				     "getting regulator\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 void 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);
+}
+
+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");