Commit 69d2a734 authored by Akinobu Mita's avatar Akinobu Mita Committed by Mauro Carvalho Chehab
Browse files

media: video-i2c: support runtime PM 

AMG88xx has a register for setting operating mode.  This adds support
runtime PM by changing the operating mode.

The instruction for changing sleep mode to normal mode is from the
reference specifications.

https://docid81hrs3j1.cloudfront.net/medialibrary/2017/11/PANA-S-A0002141979-1.pdf



Reviewed-by: default avatarMatt Ranostay <matt.ranostay@konsulko.com>
Acked-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: default avatarAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+samsung@kernel.org>
parent e0fe5c7b

drivers/media/i2c/video-i2c.c

+139 −2
Original line number Diff line number Diff line
@@ -17,6 +17,7 @@ 
#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/of_device.h>

#include <linux/pm_runtime.h>

#include <linux/regmap.h>

#include <linux/sched.h>

#include <linux/slab.h>
@@ -94,10 +95,23 @@ struct video_i2c_chip { 
	/* xfer function */

	int (*xfer)(struct video_i2c_data *data, char *buf);



	/* power control function */

	int (*set_power)(struct video_i2c_data *data, bool on);



	/* hwmon init function */

	int (*hwmon_init)(struct video_i2c_data *data);

};



/* Power control register */

#define AMG88XX_REG_PCTL	0x00

#define AMG88XX_PCTL_NORMAL		0x00

#define AMG88XX_PCTL_SLEEP		0x10



/* Reset register */

#define AMG88XX_REG_RST		0x01

#define AMG88XX_RST_FLAG		0x30

#define AMG88XX_RST_INIT		0x3f



/* Frame rate register */

#define AMG88XX_REG_FPSC	0x02

#define AMG88XX_FPSC_1FPS		BIT(0)
@@ -127,6 +141,59 @@ static int amg88xx_setup(struct video_i2c_data *data) 
	return regmap_update_bits(data->regmap, AMG88XX_REG_FPSC, mask, val);

}



static int amg88xx_set_power_on(struct video_i2c_data *data)

{

	int ret;



	ret = regmap_write(data->regmap, AMG88XX_REG_PCTL, AMG88XX_PCTL_NORMAL);

	if (ret)

		return ret;



	msleep(50);



	ret = regmap_write(data->regmap, AMG88XX_REG_RST, AMG88XX_RST_INIT);

	if (ret)

		return ret;



	usleep_range(2000, 3000);



	ret = regmap_write(data->regmap, AMG88XX_REG_RST, AMG88XX_RST_FLAG);

	if (ret)

		return ret;



	/*

	 * Wait two frames before reading thermistor and temperature registers

	 */

	msleep(200);



	return 0;

}



static int amg88xx_set_power_off(struct video_i2c_data *data)

{

	int ret;



	ret = regmap_write(data->regmap, AMG88XX_REG_PCTL, AMG88XX_PCTL_SLEEP);

	if (ret)

		return ret;

	/*

	 * Wait for a while to avoid resuming normal mode immediately after

	 * entering sleep mode, otherwise the device occasionally goes wrong

	 * (thermistor and temperature registers are not updated at all)

	 */

	msleep(100);



	return 0;

}



static int amg88xx_set_power(struct video_i2c_data *data, bool on)

{

	if (on)

		return amg88xx_set_power_on(data);



	return amg88xx_set_power_off(data);

}



#if IS_ENABLED(CONFIG_HWMON)



static const u32 amg88xx_temp_config[] = {
@@ -158,7 +225,15 @@ static int amg88xx_read(struct device *dev, enum hwmon_sensor_types type, 
	__le16 buf;

	int tmp;



	tmp = pm_runtime_get_sync(regmap_get_device(data->regmap));

	if (tmp < 0) {

		pm_runtime_put_noidle(regmap_get_device(data->regmap));

		return tmp;

	}



	tmp = regmap_bulk_read(data->regmap, AMG88XX_REG_TTHL, &buf, 2);

	pm_runtime_mark_last_busy(regmap_get_device(data->regmap));

	pm_runtime_put_autosuspend(regmap_get_device(data->regmap));

	if (tmp)

		return tmp;
@@ -217,6 +292,7 @@ static const struct video_i2c_chip video_i2c_chip[] = { 
		.regmap_config	= &amg88xx_regmap_config,

		.setup		= &amg88xx_setup,

		.xfer		= &amg88xx_xfer,

		.set_power	= amg88xx_set_power,

		.hwmon_init	= amg88xx_hwmon_init,

	},

};
@@ -343,14 +419,21 @@ static void video_i2c_del_list(struct vb2_queue *vq, enum vb2_buffer_state state 
static int start_streaming(struct vb2_queue *vq, unsigned int count)

{

	struct video_i2c_data *data = vb2_get_drv_priv(vq);

	struct device *dev = regmap_get_device(data->regmap);

	int ret;



	if (data->kthread_vid_cap)

		return 0;



	ret = pm_runtime_get_sync(dev);

	if (ret < 0) {

		pm_runtime_put_noidle(dev);

		goto error_del_list;

	}



	ret = data->chip->setup(data);

	if (ret)

		goto error_del_list;

		goto error_rpm_put;



	data->sequence = 0;

	data->kthread_vid_cap = kthread_run(video_i2c_thread_vid_cap, data,
@@ -359,6 +442,9 @@ static int start_streaming(struct vb2_queue *vq, unsigned int count) 
	if (!ret)

		return 0;



error_rpm_put:

	pm_runtime_mark_last_busy(dev);

	pm_runtime_put_autosuspend(dev);

error_del_list:

	video_i2c_del_list(vq, VB2_BUF_STATE_QUEUED);
@@ -374,6 +460,8 @@ static void stop_streaming(struct vb2_queue *vq) 


	kthread_stop(data->kthread_vid_cap);

	data->kthread_vid_cap = NULL;

	pm_runtime_mark_last_busy(regmap_get_device(data->regmap));

	pm_runtime_put_autosuspend(regmap_get_device(data->regmap));



	video_i2c_del_list(vq, VB2_BUF_STATE_ERROR);

}
@@ -648,6 +736,16 @@ static int video_i2c_probe(struct i2c_client *client, 
	video_set_drvdata(&data->vdev, data);

	i2c_set_clientdata(client, data);



	ret = data->chip->set_power(data, true);

	if (ret)

		goto error_unregister_device;



	pm_runtime_get_noresume(&client->dev);

	pm_runtime_set_active(&client->dev);

	pm_runtime_enable(&client->dev);

	pm_runtime_set_autosuspend_delay(&client->dev, 2000);

	pm_runtime_use_autosuspend(&client->dev);



	if (data->chip->hwmon_init) {

		ret = data->chip->hwmon_init(data);

		if (ret < 0) {
@@ -658,10 +756,19 @@ static int video_i2c_probe(struct i2c_client *client, 


	ret = video_register_device(&data->vdev, VFL_TYPE_GRABBER, -1);

	if (ret < 0)

		goto error_unregister_device;

		goto error_pm_disable;



	pm_runtime_mark_last_busy(&client->dev);

	pm_runtime_put_autosuspend(&client->dev);



	return 0;



error_pm_disable:

	pm_runtime_disable(&client->dev);

	pm_runtime_set_suspended(&client->dev);

	pm_runtime_put_noidle(&client->dev);

	data->chip->set_power(data, false);



error_unregister_device:

	v4l2_device_unregister(v4l2_dev);

	mutex_destroy(&data->lock);
@@ -680,11 +787,40 @@ static int video_i2c_remove(struct i2c_client *client) 
{

	struct video_i2c_data *data = i2c_get_clientdata(client);



	pm_runtime_get_sync(&client->dev);

	pm_runtime_disable(&client->dev);

	pm_runtime_set_suspended(&client->dev);

	pm_runtime_put_noidle(&client->dev);

	data->chip->set_power(data, false);



	video_unregister_device(&data->vdev);



	return 0;

}



#ifdef CONFIG_PM



static int video_i2c_pm_runtime_suspend(struct device *dev)

{

	struct video_i2c_data *data = i2c_get_clientdata(to_i2c_client(dev));



	return data->chip->set_power(data, false);

}



static int video_i2c_pm_runtime_resume(struct device *dev)

{

	struct video_i2c_data *data = i2c_get_clientdata(to_i2c_client(dev));



	return data->chip->set_power(data, true);

}



#endif



static const struct dev_pm_ops video_i2c_pm_ops = {

	SET_RUNTIME_PM_OPS(video_i2c_pm_runtime_suspend,

			   video_i2c_pm_runtime_resume, NULL)

};



static const struct i2c_device_id video_i2c_id_table[] = {

	{ "amg88xx", AMG88XX },

	{}
@@ -701,6 +837,7 @@ static struct i2c_driver video_i2c_driver = { 
	.driver = {

		.name	= VIDEO_I2C_DRIVER,

		.of_match_table = video_i2c_of_match,

		.pm	= &video_i2c_pm_ops,

	},

	.probe		= video_i2c_probe,

	.remove		= video_i2c_remove,

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