Hi Marek, On Sun, Nov 20, 2022 at 02:55:22PM +0100, Marek Vasut wrote: > On 8/24/22 00:22, Marek Vasut wrote: > > The MT9P006 sensor driver sporadically fails to probe because the sensor > > responds with a NACK condition to I2C address on the bus during an attempt > > to read the sensor MT9P031_CHIP_VERSION register in mt9p031_registered(). > > > > Neither the MT9P006 nor MT9P031 datasheets are clear on reset signal timing. > > Older MT9M034 [1] datasheet provides those timing figures in Appendix-A and > > indicates it is necessary to wait 850000 EXTCLK cycles before starting any > > I2C communication. > > > > Add such a delay, which does make the sporadic I2C NACK go away, so it is > > likely similar constraint applies to this sensor. > > > > [1] https://www.onsemi.com/pdf/datasheet/mt9m034-d.pdf > > > > Signed-off-by: Marek Vasut <marex@xxxxxxx> > > --- > > Cc: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > > Cc: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> > > Cc: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> > > Cc: Stefan Riedmueller <s.riedmueller@xxxxxxxxx> > > --- > > V2: - In case clk_get_rate() returns 0, use slowest supported clock > > to avoid division by zero > > Any news on this patch ? Thanks for the ping. It's in my tree now. -- Kind regards, Sakari Ailus
