[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Tomi Valkeinen]

On 22/07/14 10:49, Thierry Reding wrote:

> But what I was trying to say is that if the Read IDs command isn't an
> official DCS command, maybe it would be a better idea to use the DDB
> instead. I assume that even if it isn't the same information it would
> at least be a superset and therefore a suitable replacement.

Only if DDB commands work on that panel =). Even if a panel supports
DCS, it doesn't mean it supports all the commands.

Also, does it really matter which one to use inside a panel driver? I
don't really see any pros nor cons with either option. Except, of
course, if using one of those makes the driver's code simpler.

 Tomi


-- next part --
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: 

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Tomi Valkeinen]

On 22/07/14 06:41, YoungJun Cho wrote:

> 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.

This is my understanding also. I think the whole MIPI DCS spec
originated from Nokia's command set.

 Tomi


-- next part --
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: 

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Thierry Reding]

On Wed, Jul 30, 2014 at 04:44:21PM +0300, Tomi Valkeinen wrote:
> On 22/07/14 10:49, Thierry Reding wrote:
> 
> > But what I was trying to say is that if the Read IDs command isn't an
> > official DCS command, maybe it would be a better idea to use the DDB
> > instead. I assume that even if it isn't the same information it would
> > at least be a superset and therefore a suitable replacement.
> 
> Only if DDB commands work on that panel =). Even if a panel supports
> DCS, it doesn't mean it supports all the commands.

Indeed. I was perhaps a little na?ve and assumed this was such a great
standard command that every panel simply had to support it. But so far
I haven't yet come across a single panel that does...

> Also, does it really matter which one to use inside a panel driver? I
> don't really see any pros nor cons with either option. Except, of
> course, if using one of those makes the driver's code simpler.

Yeah, at this point I don't see why the read IDs command shouldn't be
used. It's somewhat unfortunate that it isn't mentioned in the DCS
specification at all, but specifications are only as useful to the
degree that they get implemented...

My hope had been that we would be able to automatically probe for panels
using the DDB, but it seems like that's not a practicable idea given the
almost non-existent support for it.

So as long as we can standardize on common APIs rather than per-driver
implementations, I'm good.

Thierry
-- next part --
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: 

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[YoungJun Cho]

Hi Thierry,

Sorry for late reply.

I implemented common DSI helper functions and tested in s6e3fa0 panel
(I should test with other panels).

The helper function prototypes are like below:

int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
u16 size);

int mipi_dcs_enter_sleep_mode(struct mipi_dsi_device *dsi);
int mipi_dcs_exit_sleep_mode(struct mipi_dsi_device *dsi);
int mipi_dcs_set_display_off(struct mipi_dsi_device *dsi);
int mipi_dcs_set_display_on(struct mipi_dsi_device *dsi);
int mipi_dcs_set_tear_off(struct mipi_dsi_device *dsi);

enum mipi_dcs_tear_mode {
MIPI_DCS_TEAR_MODE_VBLANK,
MIPI_DCS_TEAR_MODE_HVBLANK,
};

int mipi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
enum mipi_dcs_tear_mode mode);

Last time you recommended to implement mipi_dcs_set_tear_on() unrelated 
with mipi_dsi_dcs_write().
As you know, the only difference between mipi_dcs_xxx() except 
mipi_dcs_set_tear_on() is data(dcs command).
So I think it's better to use mipi_dsi_dcs_write() instead.
Do you agree?

And one more thing.
 From my point of view there is no initialization sequence in simple 
panel driver, so this and s6e8aa0 panel couldn't use that interface.
The s6e3fa0 and s6e8aa0 are very similar so I think it is possible to 
combine together like simple panel driver.
I want to ask you for advice on this.

Thank you.
Best regards YJ

On 07/22/2014 12:56 PM, YoungJun Cho wrote:
> Hi Thierry,
>
> Now I understand what you mean.
>
> I'll implement common DSI helper functions.
>
> Thank you.
> Best regards YJ
>
> On 07/21/2014 06:35 PM, Thierry Reding wrote:
>> On Fri, Jul 18, 2014 at 10:49:35AM +0900, 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
>> [...]
> +static void s6e3fa0_set_maximum_return_packet_size(struct s6e3fa0
> *ctx,
> +unsigned int size)
> +{
> +struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
> +const struct mipi_dsi_host_ops *ops = dsi->host->ops;
> +
> +if (ops && ops->transfer) {
> +unsigned char buf[] = {size, 0};
> +struct mipi_dsi_msg msg = {
> +.channel = dsi->channel,
> +.type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE,
> +.tx_len = sizeof(buf),
> +.tx_buf = buf
> +};
> +
> +ops->transfer(dsi->host, &msg);
> +}
> +}

 The Set Maximum Return Packet Size command is a standard command, so
 please turn that into a generic function exposed by the DSI core.

>>>
>>> For this and below standard DCS commands, you want to use generic
>>> functions,
>>> but I have no idea for that.
>>> Could you explain more detail?
>>
>> The goal should be to make these standard DCS commands available to all
>> DSI peripherals, so the implementation should look something like this:
>>
>> static int mipi_dsi_set_maximum_return_packet_size(struct
>> mipi_dsi_device *dsi,
>>u16 size)
>> {
>> struct mipi_dsi_msg msg;
>>
>> if (!dsi->ops || !dsi->ops->transfer)
>> return -ENOSYS;
>>
>> memset(&msg, 0, sizeof(msg));
>> msg.channel = dsi->channel;
>> msg.type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE;
>> msg.tx_len = sizeof(size);
>> msg.tx_buf = &size;
>>
>> return dsi->ops->transfer(dsi->host, &msg);
>> }
>>
>> The above is somewhat special, since it isn't DCS. For DCS I'd suggest a
>> common prefix, like so:
>>
>> enum mipi_dcs_tear_mode {
>> MIPI_DCS_TEAR_VBLANK,
>> MIPI_DCS_TEAR_BLANK,
>> };
>>
>> static int mipi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
>> enum mipi_dcs_tear_mode mode)
>> {
>> u8 data[2] = { MIPI_DSI_DCS_SET_TEAR_ON, mode };
>> struct mipi_dsi_msg msg;
>>
>> if (!dsi->ops || !dsi->ops->transfer)
>> return -ENOSYS;
>>
>> memset(&msg, 0, sizeof(msg));
>> msg.channel = dsi->channel;
>> msg.type = MIPI_DSI_DCS_SHORT_WRITE_PARAM;
>> msg.tx_len = sizeof(data);
>> msg.tx_buf = data;
>>
>> return dsi->ops->transfer(dsi->host, &msg);
>> }
>>
>> Thierry
>>
>
> ___
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
>

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[YoungJun Cho]

Hi Thierry,

On 07/22/2014 04:49 PM, Thierry Reding wrote:
> On Tue, Jul 22, 2014 at 12:41:21PM +0900, YoungJun Cho wrote:
>> 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:
>> On 07/17/2014 07:36 PM, Thierry Reding wrote:
>>> On Thu, Jul 17, 2014 at 06:01:25PM +0900, YoungJun Cho wrote:
> [...]
 +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.
>
> Okay, that explains things a little better. Can you point me to the
> document that this is from?

Sorry, I forgot to write specification name.
This specification is s6e3fa0 data sheet and it is confidential.
So I quoted only that portion.

>
> But what I was trying to say is that if the Read IDs command isn't an
> official DCS command, maybe it would be a better idea to use the DDB
> instead. I assume that even if it isn't the same information it would
> at least be a superset and therefore a suitable replacement.

This panel has several versions and each should set specific tuning 
value especially for AID, ELVSS and etc.
(Current is suitable for id[2] == 0x23).

I'll check READ_DDB_START & READ_DDB_CONTINUE result and try to use them 
if it is possible.

Thank you.
Best regards YJ

>
> Thierry
>

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[YoungJun Cho]

Hi Thierry,

Now I understand what you mean.

I'll implement common DSI helper functions.

Thank you.
Best regards YJ

On 07/21/2014 06:35 PM, Thierry Reding wrote:
> On Fri, Jul 18, 2014 at 10:49:35AM +0900, 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
> [...]
 +static void s6e3fa0_set_maximum_return_packet_size(struct s6e3fa0 *ctx,
 +  unsigned int size)
 +{
 +  struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
 +  const struct mipi_dsi_host_ops *ops = dsi->host->ops;
 +
 +  if (ops && ops->transfer) {
 +  unsigned char buf[] = {size, 0};
 +  struct mipi_dsi_msg msg = {
 +  .channel = dsi->channel,
 +  .type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE,
 +  .tx_len = sizeof(buf),
 +  .tx_buf = buf
 +  };
 +
 +  ops->transfer(dsi->host, &msg);
 +  }
 +}
>>>
>>> The Set Maximum Return Packet Size command is a standard command, so
>>> please turn that into a generic function exposed by the DSI core.
>>>
>>
>> For this and below standard DCS commands, you want to use generic functions,
>> but I have no idea for that.
>> Could you explain more detail?
>
> The goal should be to make these standard DCS commands available to all
> DSI peripherals, so the implementation should look something like this:
>
> static int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device 
> *dsi,
>  u16 size)
> {
>   struct mipi_dsi_msg msg;
>
>   if (!dsi->ops || !dsi->ops->transfer)
>   return -ENOSYS;
>
>   memset(&msg, 0, sizeof(msg));
>   msg.channel = dsi->channel;
>   msg.type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE;
>   msg.tx_len = sizeof(size);
>   msg.tx_buf = &size;
>
>   return dsi->ops->transfer(dsi->host, &msg);
> }
>
> The above is somewhat special, since it isn't DCS. For DCS I'd suggest a
> common prefix, like so:
>
> enum mipi_dcs_tear_mode {
>   MIPI_DCS_TEAR_VBLANK,
>   MIPI_DCS_TEAR_BLANK,
> };
>
> static int mipi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
>   enum mipi_dcs_tear_mode mode)
> {
>   u8 data[2] = { MIPI_DSI_DCS_SET_TEAR_ON, mode };
>   struct mipi_dsi_msg msg;
>
>   if (!dsi->ops || !dsi->ops->transfer)
>   return -ENOSYS;
>
>   memset(&msg, 0, sizeof(msg));
>   msg.channel = dsi->channel;
>   msg.type = MIPI_DSI_DCS_SHORT_WRITE_PARAM;
>   msg.tx_len = sizeof(data);
>   msg.tx_buf = data;
>
>   return dsi->ops->transfer(dsi->host, &msg);
> }
>
> Thierry
>

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[YoungJun Cho]

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_PARAMETER0xb0
>> +#define MCS_AID 0xb2
>> +#define MCS_ELVSSOPT0xb6
>> +#define MCS_TEMPERATURE_SET 0xb8
>> +#define MCS_PENTILE_CTRL0xc0
>> +#define MCS_GAMMA_MODE  0xca
>> +#define MCS_VDDM0xd7
>> +#define MCS_ALS 0xe3
>> +#define MCS_ERR_FG  0xed
>> +#define MCS_KEY_LEV10xf0
>> +#define MCS_GAMMA_UPDATE0xf7
>> +#define MCS_KEY_LEV20xfc
>> +#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 regard

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Thierry Reding]

On Tue, Jul 22, 2014 at 12:41:21PM +0900, YoungJun Cho wrote:
> 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:
> On 07/17/2014 07:36 PM, Thierry Reding wrote:
> >On Thu, Jul 17, 2014 at 06:01:25PM +0900, YoungJun Cho wrote:
[...]
> >>+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.

Okay, that explains things a little better. Can you point me to the
document that this is from?

But what I was trying to say is that if the Read IDs command isn't an
official DCS command, maybe it would be a better idea to use the DDB
instead. I assume that even if it isn't the same information it would
at least be a superset and therefore a suitable replacement.

Thierry
-- next part --
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: 

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Andrzej Hajda]

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
> 

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Thierry Reding]

On Fri, Jul 18, 2014 at 10:49:35AM +0900, 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
[...]
> > >+static void s6e3fa0_set_maximum_return_packet_size(struct s6e3fa0 *ctx,
> > >+  unsigned int size)
> > >+{
> > >+  struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
> > >+  const struct mipi_dsi_host_ops *ops = dsi->host->ops;
> > >+
> > >+  if (ops && ops->transfer) {
> > >+  unsigned char buf[] = {size, 0};
> > >+  struct mipi_dsi_msg msg = {
> > >+  .channel = dsi->channel,
> > >+  .type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE,
> > >+  .tx_len = sizeof(buf),
> > >+  .tx_buf = buf
> > >+  };
> > >+
> > >+  ops->transfer(dsi->host, &msg);
> > >+  }
> > >+}
> >
> > The Set Maximum Return Packet Size command is a standard command, so
> > please turn that into a generic function exposed by the DSI core.
> >
> 
> For this and below standard DCS commands, you want to use generic functions,
> but I have no idea for that.
> Could you explain more detail?

The goal should be to make these standard DCS commands available to all
DSI peripherals, so the implementation should look something like this:

static int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
   u16 size)
{
struct mipi_dsi_msg msg;

if (!dsi->ops || !dsi->ops->transfer)
return -ENOSYS;

memset(&msg, 0, sizeof(msg));
msg.channel = dsi->channel;
msg.type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE;
msg.tx_len = sizeof(size);
msg.tx_buf = &size;

return dsi->ops->transfer(dsi->host, &msg);
}

The above is somewhat special, since it isn't DCS. For DCS I'd suggest a
common prefix, like so:

enum mipi_dcs_tear_mode {
MIPI_DCS_TEAR_VBLANK,
MIPI_DCS_TEAR_BLANK,
};

static int mipi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
enum mipi_dcs_tear_mode mode)
{
u8 data[2] = { MIPI_DSI_DCS_SET_TEAR_ON, mode };
struct mipi_dsi_msg msg;

if (!dsi->ops || !dsi->ops->transfer)
return -ENOSYS;

memset(&msg, 0, sizeof(msg));
msg.channel = dsi->channel;
msg.type = MIPI_DSI_DCS_SHORT_WRITE_PARAM;
msg.tx_len = sizeof(data);
msg.tx_buf = data;

return dsi->ops->transfer(dsi->host, &msg);
}

Thierry
-- next part --
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: 

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Thierry Reding]

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.

Thierry
-- next part --
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: 

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Andrzej Hajda]

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_AID0xb2
>>> +#define MCS_ELVSSOPT   0xb6
>>> +#define MCS_TEMPERATURE_SET0xb8
>>> +#define MCS_PENTILE_CTRL   0xc0
>>> +#define MCS_GAMMA_MODE 0xca
>>> +#define MCS_VDDM   0xd7
>>> +#define MCS_ALS0xe3
>>> +#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_HSYNC0xff
>>> +
>>> +/* 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

>>> +#define MTP_ID_LEN 3
>>> +#define GAMMA_LEVEL_NUM30
>>> +
>>> +#define DEFAULT_VDDM_VAL   0x15
>>> +
>>> +struct s6e3fa0 {
>>> +   struct device   *dev;
>>> +   struct drm_panelpanel;
>>> +
>>> +   struct regulator_bulk_data  supplies[2];
>>> +   struct gpio_desc*reset_gpio;
>>> +   struct videomodevm;
>>> +
>>> +   unsigned intpower_on_delay;
>>> +   unsigned intreset_delay;
>>> +   unsigned intinit_delay;
>>> +   unsigned intwidth_mm;
>>> +   unsigned intheight_mm;
>>> +
>>> +   unsigned char   id;
>>> +   unsigned char   vddm;
>>> +   unsigned intbrightness;
>>> +};
>> Please don't use this kind of artificial padding. A simple space will
>> do.
>>
>>> +
>>> +#define panel_to_s6e3fa0(p) container_of(p, struct s6e3fa0, panel)
>> Please turn this into a function so we can get proper type checking.
>>
>>> +
>>> +/* VDD Memory Lookup Table contains pairs of {ReadValue, WriteValue} */
>>> +static const unsigned char s6e3fa0_vddm_lut[][2] = {
>>> +   {0x00, 0x0d}, {0x01, 0x0d}, {0x02, 0x0e}, {0x03, 0x0f}, {0x04, 0x10},
>>> +   {0x05, 0x11}, {0x06, 0x12}, {0x07, 0x13}, {0x08, 0x14}, {0x09, 0x15},
>>> +   {0x0a, 0x16}, {0x0b, 0x17}, {0x0c, 0x18}, {0x0d, 0x19}, {0x0e, 0x1a},
>>> +   {0x0f, 0x1b}, {0x10, 0x1c}, {0x11, 0x1d}, {0x12, 0x1e}, {0x13, 0x1f},
>>> +   {0x14, 0x20}, {0x15, 0x21}, {0x16, 0x22}, {0x17, 0x23}, {0x18, 0x24},
>>> +   {0x19, 0x25}, {0x1a, 0x26}, {0x1b, 0x27}, {0x1c, 0x28}, {0x1d, 0x29},
>>> +   {0x1e, 0x2a}, {0x1f, 0x2b}, {0x20, 0x2c}, {0x21, 0x2d}, {0x22, 0x2e},
>>> +   {0x23, 0x2f}, {0x24, 0x30}, {0x25, 0x31}, {0x26, 0x32}, {0x27, 0x33},
>>> +   {0x28, 0x34}, {0x29, 0x35}, {0x2a, 0x36}, {0x2b, 0x37}, {0x2c, 0x38},
>>> +   {0x2d, 0x39}, {0x2e, 0x3a}, {0x2f, 0x3b}, {0x30, 0x3c}, {0x31, 0x3d},
>>> +   {0x32, 0x3e}, {0x33, 0x3f}, {0x34, 0x3f}, {0x35, 0x3f}, {0x36, 0x3f},
>>> +   {0x37, 0x3f}, {0x38, 0x3f}, {0x39, 0x3f}, {0x3a, 0x3f}, {0x3b, 0x3f},
>>> +   {0x3c, 0x3f}, {0x3d, 0x3f}, {0x3e, 0x3f}, {0x3f, 0x3f}, {0x40, 0x0c},
>>> +   {0x41, 0x0b}, {0x42, 0x0a}, {0x43, 0x09}, {0x44, 0x08}, {0x45, 0x07},
>>> +   {0x46, 0x06}, {0x47, 0x05}, {0x48, 0x04}, {0x49, 0x03}, {0x4a, 0x02},
>>> +   {0x4b, 0x01}, {0x4c, 0x40}, {0x4d, 0x41}, {0x4e, 0x42}, {0x4f, 0x43},
>>> +   {0x50, 0x44}, {0x51, 0x45}, {0x52, 0x46}, {0x53, 0x47}, {0x54, 0x48},
>>> +   {0x55, 0x49}, {0x56, 0x4a}, {0x57, 0x4b}, {0x58, 0x4c}, {0x59, 0x4d},
>>> +   {0x5a, 0x4e}, {0x5b, 0x4f}, {0x5c, 0x50}, {0x5d, 0x51}, {0x5e, 0x52},
>>> +   {0x5f, 0x53}, {0x60, 0x54}, {0x61, 0x55}, {0x62, 0x56}, {0x63, 0x57},
>>> +   {0x64, 0x58}, {0x65, 0x59}, {0x66, 0x5a}, {0x67, 0x5b}, {0x68, 0x5c},
>>> +   {0x69, 0x5d}, {0x6a, 0x5e}, {0x6b, 0x5f}, {0x6c, 0x60}, {0x6d, 0x61},
>>> +   {0x6e, 0x62}, {0x6f, 0x63}, {0x70, 0x64}, {0x71, 0x65}, {0x72, 0x66},
>>> +   {0x73, 0x67}, {0x74, 0x68}, {0x75, 0x69}, {0x76, 0x6a}, {0x77, 0x6b},
>>> +   {0x78, 0x6c}, {0x79, 0x6d}, {0x7a, 0x6e}, {0x7b, 0x6f}, {0x7c, 0x70},
>>> +   {0x7d, 0x71}, {0x7e, 0x72}, {0x7f, 0x73},
>>> +};
>> What's this used for?
>>

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[YoungJun Cho]

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_PARAMETER0xb0
>> +#define MCS_AID 0xb2
>> +#define MCS_ELVSSOPT0xb6
>> +#define MCS_TEMPERATURE_SET 0xb8
>> +#define MCS_PENTILE_CTRL0xc0
>> +#define MCS_GAMMA_MODE  0xca
>> +#define MCS_VDDM0xd7
>> +#define MCS_ALS 0xe3
>> +#define MCS_ERR_FG  0xed
>> +#define MCS_KEY_LEV10xf0
>> +#define MCS_GAMMA_UPDATE0xf7
>> +#define MCS_KEY_LEV20xfc
>> +#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.

>> +#define MTP_ID_LEN  3
>> +#define GAMMA_LEVEL_NUM 30
>> +
>> +#define DEFAULT_VDDM_VAL0x15
>> +
>> +struct s6e3fa0 {
>> +struct device   *dev;
>> +struct drm_panelpanel;
>> +
>> +struct regulator_bulk_data  supplies[2];
>> +struct gpio_desc*reset_gpio;
>> +struct videomodevm;
>> +
>> +unsigned intpower_on_delay;
>> +unsigned intreset_delay;
>> +unsigned intinit_delay;
>> +unsigned intwidth_mm;
>> +unsigned intheight_mm;
>> +
>> +unsigned char   id;
>> +unsigned char   vddm;
>> +unsigned intbrightness;
>> +};
>
> Please don't use this kind of artificial padding. A simple space will
> do.
>
>> +
>> +#define panel_to_s6e3fa0(p) container_of(p, struct s6e3fa0, panel)
>
> Please turn this into a function so we can get proper type checking.
>
>> +
>> +/* VDD Memory Lookup Table contains pairs of {ReadValue, WriteValue} */
>> +static const unsigned char s6e3fa0_vddm_lut[][2] = {
>> +{0x00, 0x0d}, {0x01, 0x0d}, {0x02, 0x0e}, {0x03, 0x0f}, {0x04, 0x10},
>> +{0x05, 0x11}, {0x06, 0x12}, {0x07, 0x13}, {0x08, 0x14}, {0x09, 0x15},
>> +{0x0a, 0x16}, {0x0b, 0x17}, {0x0c, 0x18}, {0x0d, 0x19}, {0x0e, 0x1a},
>> +{0x0f, 0x1b}, {0x10, 0x1c}, {0x11, 0x1d}, {0x12, 0x1e}, {0x13, 0x1f},
>> +{0x14, 0x20}, {0x15, 0x21}, {0x16, 0x22}, {0x17, 0x23}, {0x18, 0x24},
>> +{0x19, 0x25}, {0x1a, 0x26}, {0x1b, 0x27}, {0x1c, 0x28}, {0x1d, 0x29},
>> +{0x1e, 0x2a}, {0x1f, 0x2b}, {0x20, 0x2c}, {0x21, 0x2d}, {0x22, 0x2e},
>> +{0x23, 0x2f}, {0x24, 0x30}, {0x25, 0x31}, {0x26, 0x32}, {0x27, 0x33},
>> +{0x28, 0x34}, {0x29, 0x35}, {0x2a, 0x36}, {0x2b, 0x37}, {0x2c, 0x38},
>> +{0x2d, 0x39}, {0x2e, 0x3a}, {0x2f, 0x3b}, {0x30, 0x3c}, {0x31, 0x3d},
>> +{0x32, 0x3e}, {0x33, 0x3f}, {0x34, 0x3f}, {0x35, 0x3f}, {0x36, 0x3f},
>> +{0x37, 0x3f}, {0x38, 0x3f}, {0x39, 0x3f}, {0x3a, 0x3f}, {0x3b, 0x3f},
>> +{0x3c, 0x3f}, {0x3d, 0x3f}, {0x3e, 0x3f}, {0x3f, 0x3f}, {0x40, 0x0c},
>> +{0x41, 0x0b}, {0x42, 0x0a}, {0x43, 0x09}, {0x44, 0x08}, {0x45, 0x07},
>> +{0x46, 0x06}, {0x47, 0x05}, {0x48, 0x04}, {0x49, 0x03}, {0x4a, 0x02},
>> +{0x4b, 0x01}, {0x4c, 0x40}, {0x4d, 0x41}, {0x4e, 0x42}, {0x4f, 0x43},
>> +{0x50, 0x44}, {0x51, 0x45}, {0x52, 0x46}, {0x53, 0x47}, {0x54, 0x48},
>> +{0x55, 0x49}, {0x56, 0x4a}, {0x57, 0x4b}, {0x58, 0x4c}, {0x59, 0x4d},
>> +{0x5a, 0x4e}, {0x5b, 0x4f}, {0x5c, 0x50}, {0x5d, 0x51}, {0x5e, 0x52},
>> +{0x5f, 0x53}, {0x60, 0x54}, {0x61, 0x55}, {0x62, 0x56}, {0x63, 0x57},
>> +{0x64, 0x58}, {0x65, 0x59}, {0x66, 0x5a}, {0x67, 0x5b}, {0x68, 0x5c},
>> +{0x69, 0x5d}, {0x6a, 0x5e}, {0x6b, 0x5f}, {0x6c, 0x60}, {0x6d, 0x61},
>> +{0x6e, 0x62}, {0x6f, 0x63}, {0x70, 0x64}, {0x71, 0x65}, {0x72, 0x66},
>> +{0x73, 0x67}, {0x74, 0x68}, {0x75, 0x69}, {0x76, 0x6a}, {0x77, 0x6b},
>> +{0x78, 0x6c}, {0x79, 0x6d}, {0x7a, 0x6e}, {0x7b, 0x6f}, {0x7c, 0x70},
>> +{0x7d, 0x71}, {0x7e, 0x72}, {0x7f, 0x73},
>> +};
>
> What's this used for?
>

This ldi contains an internal memory and requires an appropriate VDD.
Each panel stores OTP value for this vddm, so reads this value, finds 
matching value with vddm_lut and writes the final value to avoid noise 
issues from an inappropriate VDD.

>> +static int s6e3fa0_dcs_read(struct s6e3fa0 *ctx, unsigned char cmd,
>> +voi

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[YoungJun Cho]

This patch adds MIPI DSI command mode based
S6E3FA0 AMOLED LCD Panel driver.

Signed-off-by: YoungJun Cho 
Acked-by: Inki Dae 
Acked-by: Kyungmin Park 
---
 drivers/gpu/drm/panel/Kconfig |   7 +
 drivers/gpu/drm/panel/Makefile|   1 +
 drivers/gpu/drm/panel/panel-s6e3fa0.c | 541 ++
 3 files changed, 549 insertions(+)
 create mode 100644 drivers/gpu/drm/panel/panel-s6e3fa0.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 4ec874d..be1392e 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -30,4 +30,11 @@ config DRM_PANEL_S6E8AA0
select DRM_MIPI_DSI
select VIDEOMODE_HELPERS

+config DRM_PANEL_S6E3FA0
+   tristate "S6E3FA0 DSI command mode panel"
+   depends on DRM && DRM_PANEL
+   depends on OF
+   select DRM_MIPI_DSI
+   select VIDEOMODE_HELPERS
+
 endmenu
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 8b92921..85c6738 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -1,3 +1,4 @@
 obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o
 obj-$(CONFIG_DRM_PANEL_LD9040) += panel-ld9040.o
 obj-$(CONFIG_DRM_PANEL_S6E8AA0) += panel-s6e8aa0.o
+obj-$(CONFIG_DRM_PANEL_S6E3FA0) += panel-s6e3fa0.o
diff --git a/drivers/gpu/drm/panel/panel-s6e3fa0.c 
b/drivers/gpu/drm/panel/panel-s6e3fa0.c
new file mode 100644
index 000..811ec92
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-s6e3fa0.c
@@ -0,0 +1,541 @@
+/*
+ * MIPI DSI command mode based s6e3fa0 AMOLED LCD 5.7 inch drm panel driver.
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd
+ *
+ * YoungJun Cho 
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include 
+#include 
+#include 
+
+#include 
+#include 
+#include 
+
+#include 
+#include 
+#include 
+
+/* Manufacturer Command Set */
+#define MCS_GLOBAL_PARAMETER   0xb0
+#define MCS_AID0xb2
+#define MCS_ELVSSOPT   0xb6
+#define MCS_TEMPERATURE_SET0xb8
+#define MCS_PENTILE_CTRL   0xc0
+#define MCS_GAMMA_MODE 0xca
+#define MCS_VDDM   0xd7
+#define MCS_ALS0xe3
+#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_HSYNC0xff
+
+/* Content Adaptive Brightness Control */
+#define DCS_WRITE_CABC 0x55
+
+#define MTP_ID_LEN 3
+#define GAMMA_LEVEL_NUM30
+
+#define DEFAULT_VDDM_VAL   0x15
+
+struct s6e3fa0 {
+   struct device   *dev;
+   struct drm_panelpanel;
+
+   struct regulator_bulk_data  supplies[2];
+   struct gpio_desc*reset_gpio;
+   struct videomodevm;
+
+   unsigned intpower_on_delay;
+   unsigned intreset_delay;
+   unsigned intinit_delay;
+   unsigned intwidth_mm;
+   unsigned intheight_mm;
+
+   unsigned char   id;
+   unsigned char   vddm;
+   unsigned intbrightness;
+};
+
+#define panel_to_s6e3fa0(p) container_of(p, struct s6e3fa0, panel)
+
+/* VDD Memory Lookup Table contains pairs of {ReadValue, WriteValue} */
+static const unsigned char s6e3fa0_vddm_lut[][2] = {
+   {0x00, 0x0d}, {0x01, 0x0d}, {0x02, 0x0e}, {0x03, 0x0f}, {0x04, 0x10},
+   {0x05, 0x11}, {0x06, 0x12}, {0x07, 0x13}, {0x08, 0x14}, {0x09, 0x15},
+   {0x0a, 0x16}, {0x0b, 0x17}, {0x0c, 0x18}, {0x0d, 0x19}, {0x0e, 0x1a},
+   {0x0f, 0x1b}, {0x10, 0x1c}, {0x11, 0x1d}, {0x12, 0x1e}, {0x13, 0x1f},
+   {0x14, 0x20}, {0x15, 0x21}, {0x16, 0x22}, {0x17, 0x23}, {0x18, 0x24},
+   {0x19, 0x25}, {0x1a, 0x26}, {0x1b, 0x27}, {0x1c, 0x28}, {0x1d, 0x29},
+   {0x1e, 0x2a}, {0x1f, 0x2b}, {0x20, 0x2c}, {0x21, 0x2d}, {0x22, 0x2e},
+   {0x23, 0x2f}, {0x24, 0x30}, {0x25, 0x31}, {0x26, 0x32}, {0x27, 0x33},
+   {0x28, 0x34}, {0x29, 0x35}, {0x2a, 0x36}, {0x2b, 0x37}, {0x2c, 0x38},
+   {0x2d, 0x39}, {0x2e, 0x3a}, {0x2f, 0x3b}, {0x30, 0x3c}, {0x31, 0x3d},
+   {0x32, 0x3e}, {0x33, 0x3f}, {0x34, 0x3f}, {0x35, 0x3f}, {0x36, 0x3f},
+   {0x37, 0x3f}, {0x38, 0x3f}, {0x39, 0x3f}, {0x3a, 0x3f}, {0x3b, 0x3f},
+   {0x3c, 0x3f}, {0x3d, 0x3f}, {0x3e, 0x3f}, {0x3f, 0x3f}, {0x40, 0x0c},
+   {0x41, 0x0b}, {0x42, 0x0a}, {0x43, 0x09}, {0x44, 0x08}, {0x45, 0x07},
+   {0x46, 0x06}, {0x47, 0x05}, {0x48, 0x04}, {0x49, 0x03}, {0x4a, 0x02},
+   {0x4b, 0x01}, {0x4c, 0x40}, {0x4d, 0x41}, {0x4e, 0x42}, {0x4f, 0x43},
+   {0x50, 0x44}, {0x51, 0x45}, {0x52, 0x46}, {0x53, 0x47}, {0x54, 0x48},
+   {0x55, 0x49}, {0x56, 0

[PATCH v6 10/14] drm/panel: add S6E3FA0 driver

[Thierry Reding]

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?

> +#define MTP_ID_LEN   3
> +#define GAMMA_LEVEL_NUM  30
> +
> +#define DEFAULT_VDDM_VAL 0x15
> +
> +struct s6e3fa0 {
> + struct device   *dev;
> + struct drm_panelpanel;
> +
> + struct regulator_bulk_data  supplies[2];
> + struct gpio_desc*reset_gpio;
> + struct videomodevm;
> +
> + unsigned intpower_on_delay;
> + unsigned intreset_delay;
> + unsigned intinit_delay;
> + unsigned intwidth_mm;
> + unsigned intheight_mm;
> +
> + unsigned char   id;
> + unsigned char   vddm;
> + unsigned intbrightness;
> +};

Please don't use this kind of artificial padding. A simple space will
do.

> +
> +#define panel_to_s6e3fa0(p) container_of(p, struct s6e3fa0, panel)

Please turn this into a function so we can get proper type checking.

> +
> +/* VDD Memory Lookup Table contains pairs of {ReadValue, WriteValue} */
> +static const unsigned char s6e3fa0_vddm_lut[][2] = {
> + {0x00, 0x0d}, {0x01, 0x0d}, {0x02, 0x0e}, {0x03, 0x0f}, {0x04, 0x10},
> + {0x05, 0x11}, {0x06, 0x12}, {0x07, 0x13}, {0x08, 0x14}, {0x09, 0x15},
> + {0x0a, 0x16}, {0x0b, 0x17}, {0x0c, 0x18}, {0x0d, 0x19}, {0x0e, 0x1a},
> + {0x0f, 0x1b}, {0x10, 0x1c}, {0x11, 0x1d}, {0x12, 0x1e}, {0x13, 0x1f},
> + {0x14, 0x20}, {0x15, 0x21}, {0x16, 0x22}, {0x17, 0x23}, {0x18, 0x24},
> + {0x19, 0x25}, {0x1a, 0x26}, {0x1b, 0x27}, {0x1c, 0x28}, {0x1d, 0x29},
> + {0x1e, 0x2a}, {0x1f, 0x2b}, {0x20, 0x2c}, {0x21, 0x2d}, {0x22, 0x2e},
> + {0x23, 0x2f}, {0x24, 0x30}, {0x25, 0x31}, {0x26, 0x32}, {0x27, 0x33},
> + {0x28, 0x34}, {0x29, 0x35}, {0x2a, 0x36}, {0x2b, 0x37}, {0x2c, 0x38},
> + {0x2d, 0x39}, {0x2e, 0x3a}, {0x2f, 0x3b}, {0x30, 0x3c}, {0x31, 0x3d},
> + {0x32, 0x3e}, {0x33, 0x3f}, {0x34, 0x3f}, {0x35, 0x3f}, {0x36, 0x3f},
> + {0x37, 0x3f}, {0x38, 0x3f}, {0x39, 0x3f}, {0x3a, 0x3f}, {0x3b, 0x3f},
> + {0x3c, 0x3f}, {0x3d, 0x3f}, {0x3e, 0x3f}, {0x3f, 0x3f}, {0x40, 0x0c},
> + {0x41, 0x0b}, {0x42, 0x0a}, {0x43, 0x09}, {0x44, 0x08}, {0x45, 0x07},
> + {0x46, 0x06}, {0x47, 0x05}, {0x48, 0x04}, {0x49, 0x03}, {0x4a, 0x02},
> + {0x4b, 0x01}, {0x4c, 0x40}, {0x4d, 0x41}, {0x4e, 0x42}, {0x4f, 0x43},
> + {0x50, 0x44}, {0x51, 0x45}, {0x52, 0x46}, {0x53, 0x47}, {0x54, 0x48},
> + {0x55, 0x49}, {0x56, 0x4a}, {0x57, 0x4b}, {0x58, 0x4c}, {0x59, 0x4d},
> + {0x5a, 0x4e}, {0x5b, 0x4f}, {0x5c, 0x50}, {0x5d, 0x51}, {0x5e, 0x52},
> + {0x5f, 0x53}, {0x60, 0x54}, {0x61, 0x55}, {0x62, 0x56}, {0x63, 0x57},
> + {0x64, 0x58}, {0x65, 0x59}, {0x66, 0x5a}, {0x67, 0x5b}, {0x68, 0x5c},
> + {0x69, 0x5d}, {0x6a, 0x5e}, {0x6b, 0x5f}, {0x6c, 0x60}, {0x6d, 0x61},
> + {0x6e, 0x62}, {0x6f, 0x63}, {0x70, 0x64}, {0x71, 0x65}, {0x72, 0x66},
> + {0x73, 0x67}, {0x74, 0x68}, {0x75, 0x69}, {0x76, 0x6a}, {0x77, 0x6b},
> + {0x78, 0x6c}, {0x79, 0x6d}, {0x7a, 0x6e}, {0x7b, 0x6f}, {0x7c, 0x70},
> + {0x7d, 0x71}, {0x7e, 0x72}, {0x7f, 0x73},
> +};

What's this used for?

> +static int s6e3fa0_dcs_read(struct s6e3fa0 *ctx, unsigned char cmd,
> + void *data, size_t len)
> +{
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
> +
> + return mipi_dsi_dcs_read(dsi, dsi->channel, cmd, data, len);
> +}
> +
> +static void s6e3fa0_dcs_write(struct s6e3fa0 *ctx, const void *data, size_t 
> len)
> +{
> + struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev);
> +
> + mipi_dsi_dcs_write(dsi, dsi->channel, data, len);
> +}

Both mipi_dsi_dcs_read() and mipi_dsi_dcs_write() return error codes on
failure. Why are you silently ignoring them?

> +#define s6e3fa0_dcs_write_seq(ctx, seq...)   \
> +