Hi On Mon, Feb 22, 2021 at 03:18:53AM +0200, Laurent Pinchart wrote: > 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, The address reprogramming was exactly why I refrained from adding a function to the max9271 library, as handling of the addresses there would introduce a precendece order in the function calls, ie the newly introduced function would require to be called first after a chip reset and that's something I considered better handled by the camera driver (even if it wouldn't be suprising a 'wake up' function to be called first). please also note that I will next try to make the max9271 a proper i2c driver so this might be even less relevant that what it is right now Thanks j > > 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
