Hi Hans, On 03/07/17 15:45, Kieran Bingham wrote: > Hi Hans, > > Thanks for your review, > > On 03/07/17 14:51, Hans Verkuil wrote: >> On 06/27/2017 05:03 PM, Kieran Bingham wrote: >>> From: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx> >>> >>> Provide support for the ADV7481 and ADV7482. ... >>> +/* ----------------------------------------------------------------------------- >>> + * HDMI and CP >>> + */ >>> + >>> +#define ADV748X_HDMI_MIN_WIDTH 640 >>> +#define ADV748X_HDMI_MAX_WIDTH 1920 >>> +#define ADV748X_HDMI_MIN_HEIGHT 480 >>> +#define ADV748X_HDMI_MAX_HEIGHT 1200 >>> +#define ADV748X_HDMI_MIN_PIXELCLOCK 0 /* unknown */ >> >> 0 makes no sense. Something like 13000000 would work better (pixelclock rate for >> V4L2_DV_BT_CEA_720X480I59_94 is 13500000). > > This is another one that must have got lost somehow - you'd already told me this > and I'm really sure I changed it to the value you suggested ... > > /me is confused at code loss - Must have been a rebase gone bad. :-( > > >>> +#define ADV748X_HDMI_MAX_PIXELCLOCK 162000000 >> >> You probably based that on the 1600x1200p60 format? > > No idea I'm afraid - it's the value that was set when I recieved the driver... > >> >> 162MHz is a bit low for an adv receiver. The adv7604 and adv8742 have a max rate >> of 225 MHz. >> This should be documented in the datasheet. > > Hrm ... haven't found it yet - I'll keep digging.... I've found this as the most relevant reference: ================================================================================ The ADV7481 HDMI capable receiver supports a maximum pixel clock frequency of 162 MHz, allowing HDTV formats up to 1080p, and display resolutions up to UXGA (1600 × 1200 at 60 Hz). The device integrates a consumer electronics control (CEC) controller that supports the capability discovery and control (CDC) feature. The HDMI input port has dedicated 5 V detect and Hot PlugTM assert pins. ================================================================================ So that certainly looks like 162 MHz is the correct value. >> Besides, you need a bit of margin since detected pixelclock rates can be a bit off. Does that mean you would you recommend adding 0.5 MHz to the 162 MHz in a similar way as the minimum, or keep at 162 MHz ? (I'm assuming stay at 162 MHz, as the 7604 is set at 225MHz) -- Regards Kieran
