Hi,
On 07/21/2014 08:18 PM, Andrzej Hajda wrote:
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.
There is a simple description for "Read DDB Start(A1H)" like below.
- This command returns supplier identification and display module model
/ revision information.
- NOTE: This information is not the same what Read IDs(04H) command is
returning.
For reference, Read IDs(04H) description is like below.
- This read command returns 24-bit display identification information.
- The first read byte identifies the OLED module's manufacturer.
- The Second read byte is used to track the OLED module/driver version.
- The third read byte identifies the OLED module/driver.
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
Yes, this command is related with Nokia.
Last Friday, I met panel vendor guy for some issues.
At the break time, I asked him for about this Read IDs(04H), why it is
not included in DCS specification.
He said that this command was originated by Nokia.
In feature phone times, most of panel vendors wanted their panels to be
used by Nokia and Nokia wanted this command, so most of panel vendors
still provide this command traditionally.
Thank you.
Best regards YJ
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
