Re: [PATCH v3 4/8] drm/panel: Add Samsung S6E3FC2X01 DDIC with AMS641RW panel

[David Heidelberg <david@ixit.cz>]

On 16/10/2025 22:12, Dmitry Baryshkov wrote:
> On Thu, Oct 16, 2025 at 06:16:59PM +0200, David Heidelberg via B4 Relay wrote:
>> From: David Heidelberg <david@ixit.cz>
>>
>> Add panel driver used in the OnePlus 6T.
>>
>> No datasheet, based mostly on EDK2 init sequence and the downstream driver.
>>
>> Note: This driver doesn't use previously mentioned "samsung,s6e3fc2x01"
>> by OnePlus 6T device-tree.
>> The reason is because DDIC itself without knowing the panel type used
>> with it will not give the driver enough information about the panel used,
>> as the panel cannot be autodetected.
>> While would be more practical to support the original compatible,
>> I would like to avoid it, to prevent confusing devs upstreaming DDICs.
>>
>> Based on work of:
>>    Casey Connolly <casey@connolly.tech>
>>    Joel Selvaraj <foss@joelselvaraj.com>
>>    Nia Espera <a5b6@riseup.net>
>>
>> Signed-off-by: David Heidelberg <david@ixit.cz>
>> ---
>>   MAINTAINERS                                      |   1 +
>>   drivers/gpu/drm/panel/Kconfig                    |  13 +
>>   drivers/gpu/drm/panel/Makefile                   |   1 +
>>   drivers/gpu/drm/panel/panel-samsung-s6e3fc2x01.c | 399 +++++++++++++++++++++++
>>   4 files changed, 414 insertions(+)
>>
>> +
>> +static const struct drm_display_mode ams641rw_mode = {
>> +	.clock = (1080 + 72 + 16 + 36) * (2340 + 32 + 4 + 18) * 60 / 1000,
>> +	.hdisplay = 1080,
>> +	.hsync_start = 1080 + 72,
>> +	.hsync_end = 1080 + 72 + 16,
>> +	.htotal = 1080 + 72 + 16 + 36,
>> +	.vdisplay = 2340,
>> +	.vsync_start = 2340 + 32,
>> +	.vsync_end = 2340 + 32 + 4,
>> +	.vtotal = 2340 + 32 + 4 + 18,
>> +	.width_mm = 68,
>> +	.height_mm = 145,
>> +};
>> +
>> +static int s6e3fc2x01_get_modes(struct drm_panel *panel,
>> +					struct drm_connector *connector)
>> +{
>> +	struct drm_display_mode *mode;
>> +
>> +	mode = drm_mode_duplicate(connector->dev, &ams641rw_mode);
>> +	if (!mode)
>> +		return -ENOMEM;
>> +
>> +	drm_mode_set_name(mode);
>> +
>> +	mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
>> +	connector->display_info.width_mm = mode->width_mm;
>> +	connector->display_info.height_mm = mode->height_mm;
>> +	drm_mode_probed_add(connector, mode);
> 
> drm_connector_helper_get_modes_fixed()

Thanks, next version will have it.>
>> +
>> +	return 1;
>> +}
>> +
>> +
>> +static const struct of_device_id s6e3fc2x01_of_match[] = {
>> +	/* samsung,s6e3fc2x01 will default to the AMS641RW mode (legacy) */
>> +	{ .compatible = "samsung,s6e3fc2x01", .data = &ams641rw_mode },
> 
> Is there a need to probide this kind of legacy?

I don't know. I don't see the need to provide it, but I understood you 
may want to have it. If not, please tell me and I'll happily remove it 
from next version.

David

> 
>> +	{ .compatible = "samsung,s6e3fc2x01-ams641rw", .data = &ams641rw_mode },
>> +	{ /* sentinel */ }
>> +};
>> +MODULE_DEVICE_TABLE(of, s6e3fc2x01_of_match);
>> +
> 

-- 
David Heidelberg