Hello All, This is Lee Jackson from Arducam, please check the reply following. On Thu, 14 Jul 2022 17:58:31 +0200 Jacopo Mondi <jacopo@xxxxxxxxxx> wrote: > Hello Yassine > > On Thu, Jul 14, 2022 at 06:06:32PM +0400, Yassine Oudjana wrote: > > > > On Wed, Jul 13 2022 at 09:39:51 +0200, Jacopo Mondi > > <jacopo@xxxxxxxxxx> wrote: > > > Hi Yassine > > > > > > On Mon, Jul 11, 2022 at 06:40:39PM +0400, Yassine Oudjana wrote: > > > > From: Yassine Oudjana <y.oudjana@xxxxxxxxxxxxxx> > > > > > > > > Make the driver get needed regulators on probe and > > > > enable/disable them on runtime PM callbacks. > > > > > > > > Signed-off-by: Yassine Oudjana <y.oudjana@xxxxxxxxxxxxxx> > > > > > > Have you seen this ? > > > https://github.com/ArduCAM/IMX519_AK7375/blob/main/AK7375/0002-media-i2c-ak7375-driver-add-optional-regulator-suppo.patch#L172 > > > > > > It claims > > > + * Initialisation delay between VDD low->high and the > > > moment > > > + * when the i2c command is available. > > > + * From the datasheet, it should be 10ms + 2ms (max power > > > + * up sequence duration) > > > > > > 10ms seems like a long time, it would be nice to have the > > > datasheet to cross-check. > > > > It does seem quite long. I couldn't find a datasheet anywhere > > so the value I discovered is the best I have. I've added the > > author of that patch to CC; maybe they have some info to > > contribute. > > > > I have now tested these patches with an Arducam IMX519 camera. > Using a 3msec delay I get failures in the establishing i2c > communications (I only tested 2 times though). > > With 10milliseconds (which I concur is a lot) I get stable results. > Let's see if we can get more info from who has the manual. > > Thanks > j > We have the datasheet for the ak7371 and as far as we know they are not much different, here is the power up sequence for the ak7371: https://www.arducam.com/wp-content/uploads/2022/07/ak7371-power-sequence.png (We're not very familiar with working on the linux kernel mailing list yet, that's one reason we didn't submit ak7375patch, please let me know if I'm doing something wrong.) > > > > > > Thanks > > > j > > > > > > > --- > > > > 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) { > > > > -- > > > > 2.37.0 > > > > > > > >
