panel: Add driver for Novatek NT37705 panel

Thomas Zimmermann Fri, 15 May 2026 07:49:36 -0700

Hi

Am 15.05.26 um 16:31 schrieb Luca Weiss:

On Fri May 8, 2026 at 10:06 AM CEST, Thomas Zimmermann wrote:

Hi


Am 01.05.26 um 15:52 schrieb Luca Weiss:

Add support for the 2484x1116 AMOLED panel from BOE (BJ631JHM-T71-D900)
bundled with a NT37705 driver IC, as found on the Fairphone (Gen. 6)
smartphone.

The panel can also be configured in 10-bit (RGB101010) mode, however
currently it's configured in 8-bit (RGB888) since there's some issues in
the Qualcomm DPU driver when driving this panel in 10-bit.

Signed-off-by: Luca Weiss <[email protected]>
---
   drivers/gpu/drm/panel/Kconfig                 |  11 +
   drivers/gpu/drm/panel/Makefile                |   1 +
   drivers/gpu/drm/panel/panel-novatek-nt37705.c | 413 
++++++++++++++++++++++++++
   3 files changed, 425 insertions(+)

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 979109c27b9b..59ab3f29d8ef 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -624,6 +624,17 @@ config DRM_PANEL_NOVATEK_NT37700F
          Say Y here if you want to enable support for Novatek NT37700F DSI
          panel module. The panel has a resolution of 1080x2160.

+config DRM_PANEL_NOVATEK_NT37705

+       tristate "Novatek NT37705-based DSI panel"
+       depends on OF
+       depends on DRM_MIPI_DSI
+       depends on BACKLIGHT_CLASS_DEVICE
+       select DRM_KMS_HELPER
+       help
+         Say Y here if you want to enable support for Novatek NT37705-based
+         display panels, such as the one found in the The Fairphone (Gen. 6)

Duplicate 'the'

Marketing really wanted to have it be "The Fairphone". Will change and
make it saner.


How about "as the one found in Gen. 6 of The Fairphone." ?

+         smartphone.
+
   config DRM_PANEL_NOVATEK_NT37801
        tristate "Novatek NT37801/NT37810 AMOLED DSI panel"
        depends on OF
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 0d694acbfbb6..94639bc58ca8 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -61,6 +61,7 @@ obj-$(CONFIG_DRM_PANEL_NOVATEK_NT36523) += 
panel-novatek-nt36523.o
   obj-$(CONFIG_DRM_PANEL_NOVATEK_NT36672A) += panel-novatek-nt36672a.o
   obj-$(CONFIG_DRM_PANEL_NOVATEK_NT36672E) += panel-novatek-nt36672e.o
   obj-$(CONFIG_DRM_PANEL_NOVATEK_NT37700F) += panel-novatek-nt37700f.o
+obj-$(CONFIG_DRM_PANEL_NOVATEK_NT37705) += panel-novatek-nt37705.o
   obj-$(CONFIG_DRM_PANEL_NOVATEK_NT37801) += panel-novatek-nt37801.o
   obj-$(CONFIG_DRM_PANEL_NOVATEK_NT39016) += panel-novatek-nt39016.o
   obj-$(CONFIG_DRM_PANEL_MANTIX_MLAF057WE51) += panel-mantix-mlaf057we51.o
diff --git a/drivers/gpu/drm/panel/panel-novatek-nt37705.c 
b/drivers/gpu/drm/panel/panel-novatek-nt37705.c
new file mode 100644
index 000000000000..27bd8072ccd1
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-novatek-nt37705.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Generated with linux-mdss-dsi-panel-driver-generator from vendor device 
tree.
+ * Copyright (c) 2026 Luca Weiss <[email protected]>
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+
+#include <video/mipi_display.h>
+
+#include <drm/display/drm_dsc.h>
+#include <drm/display/drm_dsc_helper.h>

IIRC this requires

   select DRM_DISPLAY_DSC_HELPER

in the Kconfig. Maybe double-check.

Will check. Always difficult to figure out the proper dependencies in a
fully-featured defconfig build.

+#include <drm/drm_mipi_dsi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_probe_helper.h>
+
+struct nt37705_panel {
+       struct drm_panel panel;
+       struct mipi_dsi_device *dsi;
+       struct drm_dsc_config dsc;
+       struct regulator_bulk_data *supplies;
+       struct gpio_desc *reset_gpio;
+};
+
+static const struct regulator_bulk_data nt37705_supplies[] = {
+       { .supply = "vddio" },
+       { .supply = "dvdd" },
+       { .supply = "vci" },
+};
+
+static inline struct nt37705_panel *to_nt37705_panel(struct drm_panel *panel)
+{
+       return container_of_const(panel, struct nt37705_panel, panel);

Either just use container_of or build something that respects the
input's const-ness.

I really don't get what you mean here? Why is container_of_const() bad
here?

Because nothing is const here. It looks like an oversight or as ifsomething should be const.

+}
+
+static void nt37705_reset(struct nt37705_panel *ctx)
+{
+       gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+       usleep_range(10000, 11000);
+       gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+       usleep_range(5000, 6000);
+       gpiod_set_value_cansleep(ctx->reset_gpio, 0);
+       usleep_range(10000, 11000);
+}
+
+static int nt37705_on(struct nt37705_panel *ctx)
+{
+       struct mipi_dsi_multi_context dsi_ctx = { .dsi = ctx->dsi };
+
+       ctx->dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0,
+                                    0x55, 0xaa, 0x52, 0x08, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x1b);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba, 0x18);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x1c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x01, 0x01, 0x01, 0x01, 0x00, 0x00, 0x00,
+                                    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                                    0x00, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x2c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x00, 0x01, 0x01, 0x01, 0x00, 0x05, 0x05,
+                                    0x05, 0x00, 0x05, 0x05, 0x05, 0x00, 0x00,
+                                    0x00, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x3c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x0b,
+                                    0x0b, 0x00, 0x00, 0x0b, 0x0b, 0x00, 0x00,
+                                    0x00, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x4c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00,
+                                    0x1d, 0x00, 0x00, 0x00, 0x1d, 0x00, 0x00,
+                                    0x00, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x5c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+                                    0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+                                    0x01, 0x01);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x6c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x0b,
+                                    0x77, 0x77, 0x00, 0x00, 0x0b, 0x00, 0x1d,
+                                    0x00, 0x1d);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x7c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x0b,
+                                    0x77, 0x77, 0x00, 0x00, 0x0b, 0x00, 0x1d,
+                                    0x00, 0x1d);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x8c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                                    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                                    0x00, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x9c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x11, 0x11, 0x20, 0x02, 0x00, 0x03, 0x00,
+                                    0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0xa4);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba, 0x00, 0xc0, 0x40, 0x08);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0xa8);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,
+                                    0x22);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0xb0);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xba,
+                                    0x22, 0x22, 0x22, 0x22, 0x22, 0x22, 0x22,
+                                    0x22);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0,
+                                    0x55, 0xaa, 0x52, 0x08, 0x01);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x05);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xc5, 0x15, 0x15, 0x15, 0xdd);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0,
+                                    0x55, 0xaa, 0x52, 0x08, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x0e);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xb5, 0x32);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf0,
+                                    0x55, 0xaa, 0x52, 0x00, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xff, 0xaa, 0x55, 0xa5, 0x80);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x19);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf2, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x1a);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf4, 0x55);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x11);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf8, 0x01, 0x7f);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x2d);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf8, 0x01, 0x20);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xff, 0xaa, 0x55, 0xa5, 0x81);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x05);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfe, 0x3c);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x02);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf9, 0x04);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x1e);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfb, 0x0f);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x0f);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xf5, 0x20);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x0d);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfb, 0x80);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xff, 0xaa, 0x55, 0xa5, 0x83);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x12);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfe, 0x41);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x13);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xfd, 0x21);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0xff, 0xaa, 0x55, 0xa5, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x35);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_WRITE_CONTROL_DISPLAY,
+                                    0x20);
+       mipi_dsi_dcs_set_column_address_multi(&dsi_ctx, 0x0000, 0x045b);
+       mipi_dsi_dcs_set_page_address_multi(&dsi_ctx, 0x0000, 0x09b3);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_SET_GAMMA_CURVE, 0x00);
+       mipi_dsi_dcs_set_display_brightness_multi(&dsi_ctx, 0xbb0d);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6f, 0x04);
+       mipi_dsi_dcs_set_display_brightness_multi(&dsi_ctx, 0xfe0f);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x81, 0x01, 0x19);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x03, 0x01);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x90, 0x03, 0x03);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x91,
+                                    0x89, 0x28, 0x00, 0x0c, 0xd2, 0x00, 0x02,
+                                    0x2f, 0x01, 0x18, 0x00, 0x07, 0x09, 0x75,
+                                    0x08, 0x34, 0x10, 0xf0);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x2f, 0x02);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x5a, 0x01);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x2f, 0x30);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x6d, 0x00);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x11, 0x00);
+       mipi_dsi_msleep(&dsi_ctx, 120);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x29, 0x00);
+       mipi_dsi_msleep(&dsi_ctx, 22);
+
+       return dsi_ctx.accum_err;
+}
+
+static int nt37705_off(struct nt37705_panel *ctx)
+{
+       struct mipi_dsi_multi_context dsi_ctx = { .dsi = ctx->dsi };
+
+       ctx->dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
+
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x28, 0x00);
+       mipi_dsi_msleep(&dsi_ctx, 20);
+       mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0x10, 0x00);
+       mipi_dsi_msleep(&dsi_ctx, 120);
+
+       return dsi_ctx.accum_err;
+}
+
+static int nt37705_prepare(struct drm_panel *panel)
+{
+       struct nt37705_panel *ctx = to_nt37705_panel(panel);
+       struct device *dev = &ctx->dsi->dev;
+       struct drm_dsc_picture_parameter_set pps;
+       int ret;
+
+       ret = regulator_bulk_enable(ARRAY_SIZE(nt37705_supplies), 
ctx->supplies);
+       if (ret < 0) {

Common style is to check for errors with

    if (ret)

Here and everywhere else.

At least for regulator_bulk_enable() "ret < 0" is actually more popular
than just "ret".

Kernel doc says "Return: 0 on success or a negative error number on
failure." so a positive integer should in theory never happen so they're
equivalent.

(git grep -h -A2 regulator_bulk_enable | grep if | sed 's|^[ \t]\+||' | sed 's| 
{$||' | sort | uniq -c)


It's just nitpicking, not a blocker.

Best regards
Thomas


Thanks for the review!

Regards
Luca


--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, Werner Knoblich, (HRB 36809, AG Nürnberg)

Re: [PATCH 2/4] drm/panel: Add driver for Novatek NT37705 panel

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