On Mon, Sep 17, 2018 at 6:03 PM Akinobu Mita <akinobu.mita@xxxxxxxxx> wrote: > > 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> > Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> > --- > drivers/media/i2c/video-i2c.c | 140 +++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 138 insertions(+), 2 deletions(-) > > diff --git a/drivers/media/i2c/video-i2c.c b/drivers/media/i2c/video-i2c.c > index 916f36e..93822f4 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> > @@ -94,6 +95,9 @@ 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); > }; > @@ -104,6 +108,14 @@ static int amg88xx_xfer(struct video_i2c_data *data, char *buf) > data->chip->buffer_size); > } > > +#define AMG88XX_REG_PCTL 0x00 > +#define AMG88XX_PCTL_NORMAL 0x00 > +#define AMG88XX_PCTL_SLEEP 0x10 > + > +#define AMG88XX_REG_RST 0x01 > +#define AMG88XX_RST_FLAG 0x30 > +#define AMG88XX_RST_INIT 0x3f > + > #define AMG88XX_REG_FPSC 0x02 > #define AMG88XX_FPSC_1FPS BIT(0) > > @@ -120,6 +132,59 @@ 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[] = { > @@ -151,7 +216,15 @@ 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, 0x0e, &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; > > @@ -210,6 +283,7 @@ 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, > }, > }; > @@ -336,14 +410,21 @@ 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, > @@ -352,6 +433,9 @@ 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); > > @@ -367,6 +451,8 @@ 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); > } > @@ -627,6 +713,18 @@ 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); 2 seconds arbitrary for runtime suspending? I could be blind (or that I can't read the part English + Japanese datasheet) but not sure how much power is saved in low-power mode. In any case looks fine to me. - Matt Reviewed-by: Matt Ranostay <matt.ranostay@xxxxxxxxxxxx> > + 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) { > @@ -637,10 +735,17 @@ 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); > @@ -654,6 +759,13 @@ 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); > @@ -662,6 +774,29 @@ 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 }, > {} > @@ -678,6 +813,7 @@ 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 >
