Re: [PATCH RFC 10/10] drm/panel/sony-griffin-samsung: Add panel driver for Sony Xperia 1

From: Linus Walleij
Date: Wed Jun 28 2023 - 05:28:11 EST


On Sun, May 21, 2023 at 11:23 PM Marijn Suijten
<marijn.suijten@xxxxxxxxxxxxxx> wrote:

> The Sony Xperia 1 (codename kumano griffin) features an unnamed 4k OLED
> DSI cmd mode panel produced by Samsung. It can be driven in a
> 1644x3840@60 or 1096x2560@60 mode, and always has Display Stream
> Compression 1.1 enabled.
>
> Signed-off-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>
(...)

> +static int sony_griffin_samsung_on(struct sony_griffin_samsung *ctx)
> +{

> + ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
> + if (ret < 0) {
> + dev_err(dev, "Failed to exit sleep mode: %d\n", ret);
> + return ret;
> + }
> + usleep_range(10000, 11000);
> +
> + ret = mipi_dsi_dcs_set_tear_on(dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
> + if (ret < 0) {
> + dev_err(dev, "Failed to set tear on: %d\n", ret);
> + return ret;
> + }
> +
> + mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
> + mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x05);
> + mipi_dsi_dcs_write_seq(dsi, 0xd7, 0x07);
> + mipi_dsi_dcs_write_seq(dsi, 0xf0, 0xa5, 0xa5);
> + /* Enable backlight control */
> + mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY, BIT(5));
> + msleep(110);
> + mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
> + mipi_dsi_dcs_write_seq(dsi, 0xe2, enable_4k ? 0 : 1);
> + mipi_dsi_dcs_write_seq(dsi, 0xf0, 0xa5, 0xa5);
> +
> + ret = mipi_dsi_dcs_set_column_address(dsi, 0, hdisplay - 1);
> + if (ret < 0) {
> + dev_err(dev, "Failed to set column address: %d\n", ret);
> + return ret;
> + }
> +
> + ret = mipi_dsi_dcs_set_page_address(dsi, 0, vdisplay - 1);
> + if (ret < 0) {
> + dev_err(dev, "Failed to set page address: %d\n", ret);
> + return ret;
> + }
> +
> + mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
> + mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x70);
> + mipi_dsi_dcs_write_seq(dsi, 0xb9, 0x00, 0x60);
> + mipi_dsi_dcs_write_seq(dsi, 0xf0, 0xa5, 0xa5);
> + mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
> + mipi_dsi_dcs_write_seq(dsi, 0xc5, 0x2e, 0x21);
> + mipi_dsi_dcs_write_seq(dsi, 0xf0, 0xa5, 0xa5);
> +
> + ret = mipi_dsi_dcs_set_display_on(dsi);
> + if (ret < 0) {
> + dev_err(dev, "Failed to turn display on: %d\n", ret);
> + return ret;
> + }
> +
> + return 0;
> +}

This is eerily similar to the sequence in panel-samsung-sofef00.c:

static int sofef00_panel_on(struct sofef00_panel *ctx)
{
struct mipi_dsi_device *dsi = ctx->dsi;
struct device *dev = &dsi->dev;
int ret;

dsi->mode_flags |= MIPI_DSI_MODE_LPM;

ret = mipi_dsi_dcs_exit_sleep_mode(dsi);
if (ret < 0) {
dev_err(dev, "Failed to exit sleep mode: %d\n", ret);
return ret;
}
usleep_range(10000, 11000);

mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);

ret = mipi_dsi_dcs_set_tear_on(dsi, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
if (ret < 0) {
dev_err(dev, "Failed to set tear on: %d\n", ret);
return ret;
}

mipi_dsi_dcs_write_seq(dsi, 0xf0, 0xa5, 0xa5);
mipi_dsi_dcs_write_seq(dsi, 0xf0, 0x5a, 0x5a);
mipi_dsi_dcs_write_seq(dsi, 0xb0, 0x07);
mipi_dsi_dcs_write_seq(dsi, 0xb6, 0x12);
mipi_dsi_dcs_write_seq(dsi, 0xf0, 0xa5, 0xa5);
mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_WRITE_CONTROL_DISPLAY, 0x20);
mipi_dsi_dcs_write_seq(dsi, MIPI_DCS_WRITE_POWER_SAVE, 0x00);

ret = mipi_dsi_dcs_set_display_on(dsi);
if (ret < 0) {
dev_err(dev, "Failed to set display on: %d\n", ret);
return ret;
}

return 0;
}

Isn't this just the same display controller with a different configuration?
Especially the sleep ranges are even the same.

I almost feel like buying these phones just to pry them apart and put
under a microscope to figure out what these displays actually contain.

Yours,
Linus Walleij