Hi Jacopo, Thank you for the patch. On Wed, Feb 17, 2021 at 01:33:01PM +0000, Kieran Bingham wrote: > On 16/02/2021 17:41, Jacopo Mondi wrote: > > The MAX9271 chip manual prescribes a delay of 5 milliseconds > > after the chip exists from low power state. > > > > Adjust the required delay in the rdacm21 camera module and add it > > to the rdacm20 that currently doesn't implement one. > > This sounds to me like it should be a common function in the max9271 module: > > > /* Verify communication with the MAX9271: ping to wakeup. */ > > dev->serializer.client->addr = MAX9271_DEFAULT_ADDR; > > i2c_smbus_read_byte(dev->serializer.client); > > usleep_range(5000, 8000); > > Especially as that MAX9271_DEFAULT_ADDR should probably be handled > directly in the max9271.c file too, and the RDACM's shouldn't care about it. I think this is a good idea. With this addressed, Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > If we end up moving the max9271 'library' into more of a module/device > then this would have to be done in it's 'probe' anyway, so it's likely > better handled down there...? > > But ... it's not essential at this point in the series, so if you want > to keep this patch as is, > > Reviewed-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx> > > Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx> > > --- > > drivers/media/i2c/rdacm20.c | 1 + > > drivers/media/i2c/rdacm21.c | 2 +- > > 2 files changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/media/i2c/rdacm20.c b/drivers/media/i2c/rdacm20.c > > index ea30cc936531..39e4b4241870 100644 > > --- a/drivers/media/i2c/rdacm20.c > > +++ b/drivers/media/i2c/rdacm20.c > > @@ -460,6 +460,7 @@ static int rdacm20_initialize(struct rdacm20_device *dev) > > /* Verify communication with the MAX9271: ping to wakeup. */ > > dev->serializer.client->addr = MAX9271_DEFAULT_ADDR; > > i2c_smbus_read_byte(dev->serializer.client); > > + usleep_range(5000, 8000); > > > > /* Serial link disabled during config as it needs a valid pixel clock. */ > > ret = max9271_set_serial_link(&dev->serializer, false); > > diff --git a/drivers/media/i2c/rdacm21.c b/drivers/media/i2c/rdacm21.c > > index 179d107f494c..b22a2ca5340b 100644 > > --- a/drivers/media/i2c/rdacm21.c > > +++ b/drivers/media/i2c/rdacm21.c > > @@ -453,7 +453,7 @@ static int rdacm21_initialize(struct rdacm21_device *dev) > > /* Verify communication with the MAX9271: ping to wakeup. */ > > dev->serializer.client->addr = MAX9271_DEFAULT_ADDR; > > i2c_smbus_read_byte(dev->serializer.client); > > - usleep_range(3000, 5000); > > + usleep_range(5000, 8000); > > > > /* Enable reverse channel and disable the serial link. */ > > ret = max9271_set_serial_link(&dev->serializer, false); -- Regards, Laurent Pinchart
