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 Cc: Matt Ranostay <matt.ranostay@xxxxxxxxxxxx> Cc: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> Cc: Hans Verkuil <hansverk@xxxxxxxxx> Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> Reviewed-by: Matt Ranostay <matt.ranostay@xxxxxxxxxxxx> Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> --- * v2 - Add Reviewed-by tag - Add comment for register address definisions drivers/media/i2c/video-i2c.c | 142 +++++++++++++++++++++++++++++++++++++++++- 1 file changed, 140 insertions(+), 2 deletions(-) diff --git a/drivers/media/i2c/video-i2c.c b/drivers/media/i2c/video-i2c.c index 6dd1929..f7058cf 100644 --- a/drivers/media/i2c/video-i2c.c +++ b/drivers/media/i2c/video-i2c.c @@ -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; + + msleep(2); + + 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); } @@ -635,6 +723,18 @@ 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); + pm_runtime_mark_last_busy(&client->dev); + pm_runtime_put_autosuspend(&client->dev); + if (data->chip->hwmon_init) { ret = data->chip->hwmon_init(data); if (ret < 0) { @@ -645,10 +745,17 @@ 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; return 0; +error_pm_disable: + 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); + error_unregister_device: v4l2_device_unregister(v4l2_dev); mutex_destroy(&data->lock); @@ -662,6 +769,13 @@ static int video_i2c_remove(struct i2c_client *client) struct video_i2c_data *data = i2c_get_clientdata(client); video_unregister_device(&data->vdev); + + 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); + v4l2_device_unregister(&data->v4l2_dev); mutex_destroy(&data->lock); @@ -670,6 +784,29 @@ static int video_i2c_remove(struct i2c_client *client) 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 }, {} @@ -686,6 +823,7 @@ 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, -- 2.7.4