[PATCH v3 04/14] media: ov7670: control clock along with power
From: Lubomir Rintel <lkundrak@v3.sk>
Date: 2018-11-20 10:04:47
Also in:
linux-media, lkml
Subsystem:
media input infrastructure (v4l/dvb), omnivision ov7670 sensor driver, the rest, v4l2 camera sensor drivers · Maintainers:
Mauro Carvalho Chehab, Linus Torvalds, Sakari Ailus
This provides more power saving when the sensor is off. While at that, do the delay on power/clock enable even if the sensor driver itself doesn't control the GPIOs. This is required for the OLPC XO-1 platform, that lacks the proper power/reset properties in its DT, but needs the delay after the sensor is clocked up. Signed-off-by: Lubomir Rintel <lkundrak@v3.sk> --- drivers/media/i2c/ov7670.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-)
diff --git a/drivers/media/i2c/ov7670.c b/drivers/media/i2c/ov7670.c
index cbaab60aaaac..d7635fb2d713 100644
--- a/drivers/media/i2c/ov7670.c
+++ b/drivers/media/i2c/ov7670.c@@ -1623,14 +1623,17 @@ static void ov7670_power_on(struct v4l2_subdev *sd) if (info->on) return; + clk_prepare_enable(info->clk); + if (info->pwdn_gpio) gpiod_set_value(info->pwdn_gpio, 0); if (info->resetb_gpio) { gpiod_set_value(info->resetb_gpio, 1); usleep_range(500, 1000); gpiod_set_value(info->resetb_gpio, 0); - usleep_range(3000, 5000); } + if (info->pwdn_gpio || info->resetb_gpio || info->clk) + usleep_range(3000, 5000); info->on = true; }
@@ -1642,6 +1645,8 @@ static void ov7670_power_off(struct v4l2_subdev *sd) if (!info->on) return; + clk_disable_unprepare(info->clk); + if (info->pwdn_gpio) gpiod_set_value(info->pwdn_gpio, 1);
@@ -1863,24 +1868,20 @@ static int ov7670_probe(struct i2c_client *client, return ret; } - if (info->clk) { - ret = clk_prepare_enable(info->clk); - if (ret) - return ret; + ret = ov7670_init_gpio(client, info); + if (ret) + return ret; + ov7670_power_on(sd); + + if (info->clk) { info->clock_speed = clk_get_rate(info->clk) / 1000000; if (info->clock_speed < 10 || info->clock_speed > 48) { ret = -EINVAL; - goto clk_disable; + goto power_off; } } - ret = ov7670_init_gpio(client, info); - if (ret) - goto clk_disable; - - ov7670_power_on(sd); - /* Make sure it's an ov7670 */ ret = ov7670_detect(sd); if (ret) {
@@ -1960,6 +1961,7 @@ static int ov7670_probe(struct i2c_client *client, if (ret < 0) goto entity_cleanup; + ov7670_power_off(sd); return 0; entity_cleanup:
@@ -1968,12 +1970,9 @@ static int ov7670_probe(struct i2c_client *client, v4l2_ctrl_handler_free(&info->hdl); power_off: ov7670_power_off(sd); -clk_disable: - clk_disable_unprepare(info->clk); return ret; } - static int ov7670_remove(struct i2c_client *client) { struct v4l2_subdev *sd = i2c_get_clientdata(client);
@@ -1981,7 +1980,6 @@ static int ov7670_remove(struct i2c_client *client) v4l2_async_unregister_subdev(sd); v4l2_ctrl_handler_free(&info->hdl); - clk_disable_unprepare(info->clk); media_entity_cleanup(&info->sd.entity); ov7670_power_off(sd); return 0;
--
2.19.1