Hi, On Thu, Sep 9, 2021 at 12:09 PM Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote: > > Quoting Philip Chen (2021-09-09 11:29:19) > > Hi, > > > > On Wed, Sep 8, 2021 at 2:54 PM Stephen Boyd <swboyd@xxxxxxxxxxxx> wrote: > > > > > > Quoting Philip Chen (2021-09-08 11:18:05) > > > > diff --git a/drivers/gpu/drm/bridge/parade-ps8640.c b/drivers/gpu/drm/bridge/parade-ps8640.c > > > > index 685e9c38b2db..a16725dbf912 100644 > > > > --- a/drivers/gpu/drm/bridge/parade-ps8640.c > > > > +++ b/drivers/gpu/drm/bridge/parade-ps8640.c > > > > @@ -64,12 +65,29 @@ struct ps8640 { > > > > struct drm_bridge *panel_bridge; > > > > struct mipi_dsi_device *dsi; > > > > struct i2c_client *page[MAX_DEVS]; > > > > + struct regmap *regmap[MAX_DEVS]; > > > > struct regulator_bulk_data supplies[2]; > > > > struct gpio_desc *gpio_reset; > > > > struct gpio_desc *gpio_powerdown; > > > > bool powered; > > > > }; > > > > > > > > +static const struct regmap_range ps8640_volatile_ranges[] = { > > > > + { .range_min = 0, .range_max = 0xff }, > > > > > > Is the plan to fill this out later or is 0xff the max register? If it's > > > the latter then I think adding the max register to regmap_config is > > > simpler. > > It's the former. > > The real accessible register range is different per page, E.g.: > > - For page0, the register range is 0x00 - 0xbf. > > - For page1, the register range is 0x00 - 0xff. > > - For page2, the register range is 0x80 - 0xff. > > Oh does this have register pages? regmap has support for pages where you > write some indirection register and then access the same i2c address for > the next page. This looks different though and has a different i2c > address for each page? I haven't looked in tons of detail, but I think the right solution here is a separate regmap config per page. -Doug