On 07/21/2014 11:19 AM, Thierry Reding wrote: > On Mon, Jul 21, 2014 at 10:56:08AM +0200, Andrzej Hajda wrote: >> On 07/18/2014 03:49 AM, YoungJun Cho wrote: >>> Hi Thierry, >>> >>> Thank you a lot for kind comments. >>> >>> On 07/17/2014 07:36 PM, Thierry Reding wrote: >>>> On Thu, Jul 17, 2014 at 06:01:25PM +0900, YoungJun Cho wrote: >>>> [...] >>>>> diff --git a/drivers/gpu/drm/panel/panel-s6e3fa0.c b/drivers/gpu/drm/panel/panel-s6e3fa0.c >>>> [...] >>>>> +/* Manufacturer Command Set */ >>>>> +#define MCS_GLOBAL_PARAMETER 0xb0 >>>>> +#define MCS_AID 0xb2 >>>>> +#define MCS_ELVSSOPT 0xb6 >>>>> +#define MCS_TEMPERATURE_SET 0xb8 >>>>> +#define MCS_PENTILE_CTRL 0xc0 >>>>> +#define MCS_GAMMA_MODE 0xca >>>>> +#define MCS_VDDM 0xd7 >>>>> +#define MCS_ALS 0xe3 >>>>> +#define MCS_ERR_FG 0xed >>>>> +#define MCS_KEY_LEV1 0xf0 >>>>> +#define MCS_GAMMA_UPDATE 0xf7 >>>>> +#define MCS_KEY_LEV2 0xfc >>>>> +#define MCS_RE 0xfe >>>>> +#define MCS_TOUT2_HSYNC 0xff >>>>> + >>>>> +/* Content Adaptive Brightness Control */ >>>>> +#define DCS_WRITE_CABC 0x55 >>>> Is this not a manufacturer specific command? I couldn't find it in the >>>> DSI or DCS specifications, but it sounds like something standard (also >>>> indicated by the DCS_ prefix). Can you point out the specification for >>>> this? >>>> >>> Andrzej commented before and decided it as DCS one because if the value >>> is less than 0xb0, it is DCS one and the others are MCS one. >>> But still I'm not sure it is correct. >> I would not say 'decided'. I have just stated that according to DCS >> specification >> it should be DCS command (below 0xb0), but it is not present in mipi dcs >> specs. >> On the other side many panels have it [1]: >> >> [1]: >> https://www.google.com/search?q=%22Write+Content+Adaptive+Brightness+Control%22 > > Yeah, my search yielded similar results. I wonder if this is perhaps > part of a draft future specification. I'll try to ask around some more > if anybody knows what the status of this is. > >>>>> +static void s6e3fa0_read_mtp_id(struct s6e3fa0 *ctx) >>>>> +{ >>>>> + unsigned char id[MTP_ID_LEN]; >>>>> + int ret; >>>>> + >>>>> + s6e3fa0_set_maximum_return_packet_size(ctx, MTP_ID_LEN); >>>>> + ret = s6e3fa0_dcs_read(ctx, MIPI_DCS_GET_DISPLAY_ID, id, MTP_ID_LEN); >>>> This also looks like a standard DCS command. I can't find it in either >>>> v1.01 nor v1.02 of the specification, though. Do you know where it's >>>> specified? >>>> >>> Yes, I also can't find it in DCS specification and there is no special >>> description in panel datasheet. >>> But as it is declared in "include/video/mipi_display.h", so I think it >>> is a standard one. >> >> On page 9 of the "Introduction of MIPI by Renesas" [2] there is info >> it is a part of "Nokia I/F command list", I guess it is kind of alpha >> version of MIPI DCS. >> >> [2]: http://wenku.baidu.com/view/658fab68af1ffc4ffe47acbe.html > > That link is the only one which contains "Nokia I/F command list" on the > internet (that is, according to Google). But since this is already part > of the mipi_display.h header file we may as well use it. > > I wonder if perhaps the READ_DDB_START and READ_DDB_CONTINUE commands > could be used as a replacement for this display ID. > > Adding Guennadi, Tomi, Paul and Imre on Cc since they were involved with > the original patch that added mipi_display.h. Perhaps they remember what > the origin of this command is. I guess it was PCF8833 used in Nokia 6100 [1][2]. [1]: http://www.vintagecomputercables.com/datasheet/PCF8833_1.pdf [2]: http://www.elecfreaks.com/store/download/datasheet/shield/6100_Display_Driver.pdf Regards Andrzej > > Thierry > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
