Re: [PATCH v2 3/3] media: i2c: ak7375: Add regulator management
From: Umang Jain <hidden>
Date: 2022-11-28 06:48:09
Also in:
linux-media, lkml
Hi Yassine, I have tested this VCM with autofocus algorithm plumbed in libcamera [1] On 7/11/22 8:10 PM, Yassine Oudjana wrote:
From: Yassine Oudjana <y.oudjana@protonmail.com> Make the driver get needed regulators on probe and enable/disable them on runtime PM callbacks. Signed-off-by: Yassine Oudjana <y.oudjana@protonmail.com>
Tested-by: Umang Jain <redacted> [1] https://patchwork.libcamera.org/project/libcamera/list/?series=3174
quoted hunk ↗ jump to hunk
--- Changes since v1: - Reorganize variable declaration - Change the power-on delay range to 3000-3500 microseconds. drivers/media/i2c/ak7375.c | 39 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+)diff --git a/drivers/media/i2c/ak7375.c b/drivers/media/i2c/ak7375.c index 40b1a4aa846c..c2b2542a0056 100644 --- a/drivers/media/i2c/ak7375.c +++ b/drivers/media/i2c/ak7375.c@@ -6,6 +6,7 @@ #include <linux/i2c.h> #include <linux/module.h> #include <linux/pm_runtime.h> +#include <linux/regulator/consumer.h> #include <media/v4l2-ctrls.h> #include <media/v4l2-device.h>@@ -23,17 +24,32 @@ */ #define AK7375_CTRL_STEPS 64 #define AK7375_CTRL_DELAY_US 1000 +/* + * The vcm takes around 3 ms to power on and start taking + * I2C messages. This value was found experimentally due to + * lack of documentation. + */ +#define AK7375_POWER_DELAY_US 3000 #define AK7375_REG_POSITION 0x0 #define AK7375_REG_CONT 0x2 #define AK7375_MODE_ACTIVE 0x0 #define AK7375_MODE_STANDBY 0x40 +static const char * const ak7375_supply_names[] = { + "vdd", + "vio", +}; + +#define AK7375_NUM_SUPPLIES ARRAY_SIZE(ak7375_supply_names) + /* ak7375 device structure */ struct ak7375_device { struct v4l2_ctrl_handler ctrls_vcm; struct v4l2_subdev sd; struct v4l2_ctrl *focus; + struct regulator_bulk_data supplies[AK7375_NUM_SUPPLIES]; + /* active or standby mode */ bool active; };@@ -133,12 +149,24 @@ static int ak7375_probe(struct i2c_client *client) { struct ak7375_device *ak7375_dev; int ret; + int i; ak7375_dev = devm_kzalloc(&client->dev, sizeof(*ak7375_dev), GFP_KERNEL); if (!ak7375_dev) return -ENOMEM; + for (i = 0; i < AK7375_NUM_SUPPLIES; i++) + ak7375_dev->supplies[i].supply = ak7375_supply_names[i]; + + ret = devm_regulator_bulk_get(&client->dev, AK7375_NUM_SUPPLIES, + ak7375_dev->supplies); + if (ret) { + dev_err(&client->dev, "Failed to get regulators: %pe", + ERR_PTR(ret)); + return ret; + } + v4l2_i2c_subdev_init(&ak7375_dev->sd, client, &ak7375_ops); ak7375_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; ak7375_dev->sd.internal_ops = &ak7375_int_ops;@@ -210,6 +238,10 @@ static int __maybe_unused ak7375_vcm_suspend(struct device *dev) if (ret) dev_err(dev, "%s I2C failure: %d\n", __func__, ret); + ret = regulator_bulk_disable(AK7375_NUM_SUPPLIES, ak7375_dev->supplies); + if (ret) + return ret; + ak7375_dev->active = false; return 0;@@ -230,6 +262,13 @@ static int __maybe_unused ak7375_vcm_resume(struct device *dev) if (ak7375_dev->active) return 0; + ret = regulator_bulk_enable(AK7375_NUM_SUPPLIES, ak7375_dev->supplies); + if (ret) + return ret; + + /* Wait for vcm to become ready */ + usleep_range(AK7375_POWER_DELAY_US, AK7375_POWER_DELAY_US + 500); + ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_CONT, AK7375_MODE_ACTIVE, 1); if (ret) {