// SPDX-License-Identifier: GPL-2.0-only
// Copyright (c) 2024 Linaro Limited
#include <linux/backlight.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <drm/display/drm_dsc.h>
#include <drm/display/drm_dsc_helper.h>
#include <drm/drm_mipi_dsi.h>
#include <drm/drm_modes.h>
#include <drm/drm_panel.h>
#include <drm/drm_probe_helper.h>
#include <video/mipi_display.h>
struct novatek_nt37801 {
struct drm_panel panel;
struct mipi_dsi_device *dsi;
struct drm_dsc_config dsc;
struct gpio_desc *reset_gpio;
struct regulator_bulk_data *supplies;
};
static const struct regulator_bulk_data novatek_nt37801_supplies[] = {
{ .supply = "vddio" },
{ .supply = "vci" },
{ .supply = "vdd" },
};
static inline struct novatek_nt37801 *to_novatek_nt37801(struct drm_panel *panel)
{
return container_of(panel, struct novatek_nt37801, panel);
}
static void novatek_nt37801_reset(struct novatek_nt37801 *ctx)
{
gpiod_set_value_cansleep(ctx->reset_gpio, 0 );
usleep_range(10000 , 21000 );
gpiod_set_value_cansleep(ctx->reset_gpio, 1 );
usleep_range(10000 , 21000 );
gpiod_set_value_cansleep(ctx->reset_gpio, 0 );
usleep_range(10000 , 21000 );
}
#define NT37801_DCS_SWITCH_PAGE 0 xf0
#define novatek_nt37801_switch_page(dsi_ctx, page) \
mipi_dsi_dcs_write_seq_multi((dsi_ctx), NT37801_DCS_SWITCH_PAGE, \
0 x55, 0 xaa, 0 x52, 0 x08, (page))
static int novatek_nt37801_on(struct novatek_nt37801 *ctx)
{
struct mipi_dsi_device *dsi = ctx->dsi;
struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };
dsi->mode_flags |= MIPI_DSI_MODE_LPM;
novatek_nt37801_switch_page(&dsi_ctx, 0 x01);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x6f, 0 x01);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xc5, 0 x0b, 0 x0b, 0 x0b);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xff, 0 xaa, 0 x55, 0 xa5, 0 x80);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x6f, 0 x02);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xf5, 0 x10);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x6f, 0 x1b);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xf4, 0 x55);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x6f, 0 x18);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xf8, 0 x19);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x6f, 0 x0f);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xfc, 0 x00);
mipi_dsi_dcs_set_column_address_multi(&dsi_ctx, 0 x0000, 0 x059f);
mipi_dsi_dcs_set_page_address_multi(&dsi_ctx, 0 x0000, 0 x0c7f);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x90, 0 x03, 0 x03);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x91,
0 x89, 0 x28, 0 x00, 0 x28, 0 xc2, 0 x00, 0 x02,
0 x68, 0 x04, 0 x6c, 0 x00, 0 x0a, 0 x02, 0 x77,
0 x01, 0 xe9, 0 x10, 0 xf0);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xff, 0 xaa, 0 x55, 0 xa5, 0 x81);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x6f, 0 x23);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xfb,
0 x00, 0 x01, 0 x00, 0 x11, 0 x33, 0 x33, 0 x33,
0 x55, 0 x57, 0 xd0, 0 x00, 0 x00, 0 x44, 0 x56,
0 x77, 0 x78, 0 x9a, 0 xbc, 0 xdd, 0 xf0);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x6f, 0 x06);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xf3, 0 xdc);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_SET_GAMMA_CURVE, 0 x00);
mipi_dsi_dcs_set_tear_on_multi(&dsi_ctx, MIPI_DSI_DCS_TEAR_MODE_VBLANK);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x3b, 0 x00, 0 x18, 0 x00, 0 x10);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_WRITE_CONTROL_DISPLAY,
0 x20);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x51,
0 x07, 0 xff, 0 x07, 0 xff, 0 x0f, 0 xff);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x5a, 0 x01);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x5f, 0 x00);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x9c, 0 x01);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, MIPI_DCS_WRITE_MEMORY_START);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 x2f, 0 x00);
novatek_nt37801_switch_page(&dsi_ctx, 0 x01);
mipi_dsi_dcs_write_seq_multi(&dsi_ctx, 0 xb2, 0 x55, 0 x01, 0 xff, 0 x03);
mipi_dsi_dcs_exit_sleep_mode_multi(&dsi_ctx);
mipi_dsi_msleep(&dsi_ctx, 120 );
mipi_dsi_dcs_set_display_on_multi(&dsi_ctx);
mipi_dsi_msleep(&dsi_ctx, 20 );
return dsi_ctx.accum_err;
}
static int novatek_nt37801_off(struct novatek_nt37801 *ctx)
{
struct mipi_dsi_device *dsi = ctx->dsi;
struct mipi_dsi_multi_context dsi_ctx = { .dsi = dsi };
dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
mipi_dsi_dcs_set_display_off_multi(&dsi_ctx);
mipi_dsi_msleep(&dsi_ctx, 20 );
mipi_dsi_dcs_enter_sleep_mode_multi(&dsi_ctx);
mipi_dsi_msleep(&dsi_ctx, 120 );
return dsi_ctx.accum_err;
}
static int novatek_nt37801_prepare(struct drm_panel *panel)
{
struct novatek_nt37801 *ctx = to_novatek_nt37801(panel);
struct device *dev = &ctx->dsi->dev;
struct drm_dsc_picture_parameter_set pps;
int ret;
ret = regulator_bulk_enable(ARRAY_SIZE(novatek_nt37801_supplies),
ctx->supplies);
if (ret < 0 )
return ret;
novatek_nt37801_reset(ctx);
ret = novatek_nt37801_on(ctx);
if (ret < 0 )
goto err;
drm_dsc_pps_payload_pack(&pps, &ctx->dsc);
ret = mipi_dsi_picture_parameter_set(ctx->dsi, &pps);
if (ret < 0 ) {
dev_err(panel->dev, "failed to transmit PPS: %d\n" , ret);
goto err;
}
ret = mipi_dsi_compression_mode(ctx->dsi, true );
if (ret < 0 ) {
dev_err(dev, "failed to enable compression mode: %d\n" , ret);
goto err;
}
msleep(28 );
return 0 ;
err:
gpiod_set_value_cansleep(ctx->reset_gpio, 1 );
regulator_bulk_disable(ARRAY_SIZE(novatek_nt37801_supplies),
ctx->supplies);
return ret;
}
static int novatek_nt37801_unprepare(struct drm_panel *panel)
{
struct novatek_nt37801 *ctx = to_novatek_nt37801(panel);
struct device *dev = &ctx->dsi->dev;
int ret;
ret = novatek_nt37801_off(ctx);
if (ret < 0 )
dev_err(dev, "Failed to un-initialize panel: %d\n" , ret);
gpiod_set_value_cansleep(ctx->reset_gpio, 1 );
regulator_bulk_disable(ARRAY_SIZE(novatek_nt37801_supplies),
ctx->supplies);
return 0 ;
}
static const struct drm_display_mode novatek_nt37801_mode = {
.clock = (1440 + 20 + 4 + 20 ) * (3200 + 20 + 2 + 18 ) * 120 / 1000 ,
.hdisplay = 1440 ,
.hsync_start = 1440 + 20 ,
.hsync_end = 1440 + 20 + 4 ,
.htotal = 1440 + 20 + 4 + 20 ,
.vdisplay = 3200 ,
.vsync_start = 3200 + 20 ,
.vsync_end = 3200 + 20 + 2 ,
.vtotal = 3200 + 20 + 2 + 18 ,
.type = DRM_MODE_TYPE_DRIVER,
};
static int novatek_nt37801_get_modes(struct drm_panel *panel,
struct drm_connector *connector)
{
return drm_connector_helper_get_modes_fixed(connector,
&novatek_nt37801_mode);
}
static const struct drm_panel_funcs novatek_nt37801_panel_funcs = {
.prepare = novatek_nt37801_prepare,
.unprepare = novatek_nt37801_unprepare,
.get_modes = novatek_nt37801_get_modes,
};
static int novatek_nt37801_bl_update_status(struct backlight_device *bl)
{
struct mipi_dsi_device *dsi = bl_get_data(bl);
u16 brightness = backlight_get_brightness(bl);
int ret;
dsi->mode_flags &= ~MIPI_DSI_MODE_LPM;
ret = mipi_dsi_dcs_set_display_brightness_large(dsi, brightness);
if (ret < 0 )
return ret;
dsi->mode_flags |= MIPI_DSI_MODE_LPM;
return 0 ;
}
static const struct backlight_ops novatek_nt37801_bl_ops = {
.update_status = novatek_nt37801_bl_update_status,
};
static struct backlight_device *
novatek_nt37801_create_backlight(struct mipi_dsi_device *dsi)
{
struct device *dev = &dsi->dev;
const struct backlight_properties props = {
.type = BACKLIGHT_RAW,
.brightness = 4095 ,
.max_brightness = 4095 ,
};
return devm_backlight_device_register(dev, dev_name(dev), dev, dsi,
&novatek_nt37801_bl_ops, &props);
}
static int novatek_nt37801_probe(struct mipi_dsi_device *dsi)
{
struct device *dev = &dsi->dev;
struct novatek_nt37801 *ctx;
int ret;
ctx = devm_drm_panel_alloc(dev, struct novatek_nt37801, panel,
&novatek_nt37801_panel_funcs,
DRM_MODE_CONNECTOR_DSI);
if (IS_ERR(ctx))
return PTR_ERR(ctx);
ret = devm_regulator_bulk_get_const(dev,
ARRAY_SIZE(novatek_nt37801_supplies),
novatek_nt37801_supplies,
&ctx->supplies);
if (ret < 0 )
return ret;
ctx->reset_gpio = devm_gpiod_get(dev, "reset" , GPIOD_OUT_LOW);
if (IS_ERR(ctx->reset_gpio))
return dev_err_probe(dev, PTR_ERR(ctx->reset_gpio),
"Failed to get reset-gpios\n" );
ctx->dsi = dsi;
mipi_dsi_set_drvdata(dsi, ctx);
dsi->lanes = 4 ;
dsi->format = MIPI_DSI_FMT_RGB888;
dsi->mode_flags = MIPI_DSI_MODE_NO_EOT_PACKET | MIPI_DSI_CLOCK_NON_CONTINUOUS;
ctx->panel.prepare_prev_first = true ;
ctx->panel.backlight = novatek_nt37801_create_backlight(dsi);
if (IS_ERR(ctx->panel.backlight))
return dev_err_probe(dev, PTR_ERR(ctx->panel.backlight),
"Failed to create backlight\n" );
drm_panel_add(&ctx->panel);
/* This panel only supports DSC; unconditionally enable it */
dsi->dsc = &ctx->dsc;
ctx->dsc.dsc_version_major = 1 ;
ctx->dsc.dsc_version_minor = 1 ;
ctx->dsc.slice_height = 40 ;
ctx->dsc.slice_width = 720 ;
ctx->dsc.slice_count = 1440 / ctx->dsc.slice_width;
ctx->dsc.bits_per_component = 8 ;
ctx->dsc.bits_per_pixel = 8 << 4 ; /* 4 fractional bits */
ctx->dsc.block_pred_enable = true ;
ret = mipi_dsi_attach(dsi);
if (ret < 0 ) {
drm_panel_remove(&ctx->panel);
return dev_err_probe(dev, ret, "Failed to attach to DSI host\n" );
}
return 0 ;
}
static void novatek_nt37801_remove(struct mipi_dsi_device *dsi)
{
struct novatek_nt37801 *ctx = mipi_dsi_get_drvdata(dsi);
int ret;
ret = mipi_dsi_detach(dsi);
if (ret < 0 )
dev_err(&dsi->dev, "Failed to detach from DSI host: %d\n" , ret);
drm_panel_remove(&ctx->panel);
}
static const struct of_device_id novatek_nt37801_of_match[] = {
{ .compatible = "novatek,nt37801" },
{}
};
MODULE_DEVICE_TABLE(of, novatek_nt37801_of_match);
static struct mipi_dsi_driver novatek_nt37801_driver = {
.probe = novatek_nt37801_probe,
.remove = novatek_nt37801_remove,
.driver = {
.name = "panel-novatek-nt37801" ,
.of_match_table = novatek_nt37801_of_match,
},
};
module_mipi_dsi_driver(novatek_nt37801_driver);
MODULE_AUTHOR("Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>" );
MODULE_DESCRIPTION("Panel driver for the Novatek NT37801/NT37810 AMOLED DSI panel" );
MODULE_LICENSE("GPL" );
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