blob: 3cf4cf6a6942c3f3e33f467efa22445fccbd6998 [file] [log] [blame]
* ld9040 AMOLED LCD drm_panel driver.
* Copyright (c) 2014 Samsung Electronics Co., Ltd
* Derived from drivers/video/backlight/ld9040.c
* Andrzej Hajda <>
* 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 <drm/drmP.h>
#include <drm/drm_panel.h>
#include <linux/gpio/consumer.h>
#include <linux/regulator/consumer.h>
#include <linux/spi/spi.h>
#include <video/mipi_display.h>
#include <video/of_videomode.h>
#include <video/videomode.h>
/* Manufacturer Command Set */
#define MCS_MANPWR 0xb0
#define MCS_ELVSS_ON 0xb1
#define MCS_USER_SETTING 0xf0
#define MCS_DISPCTL 0xf2
#define MCS_POWER_CTRL 0xf4
#define MCS_GTCON 0xf7
#define MCS_GAMMA_SET1 0xf9
#define MCS_GAMMA_CTRL 0xfb
/* array of gamma tables for gamma value 2.2 */
static u8 const ld9040_gammas[25][22] = {
{ 0xf9, 0x00, 0x13, 0xb2, 0xba, 0xd2, 0x00, 0x30, 0x00, 0xaf, 0xc0,
0xb8, 0xcd, 0x00, 0x3d, 0x00, 0xa8, 0xb8, 0xb7, 0xcd, 0x00, 0x44 },
{ 0xf9, 0x00, 0x13, 0xb9, 0xb9, 0xd0, 0x00, 0x3c, 0x00, 0xaf, 0xbf,
0xb6, 0xcb, 0x00, 0x4b, 0x00, 0xa8, 0xb9, 0xb5, 0xcc, 0x00, 0x52 },
{ 0xf9, 0x00, 0x13, 0xba, 0xb9, 0xcd, 0x00, 0x41, 0x00, 0xb0, 0xbe,
0xb5, 0xc9, 0x00, 0x51, 0x00, 0xa9, 0xb9, 0xb5, 0xca, 0x00, 0x57 },
{ 0xf9, 0x00, 0x13, 0xb9, 0xb8, 0xcd, 0x00, 0x46, 0x00, 0xb1, 0xbc,
0xb5, 0xc8, 0x00, 0x56, 0x00, 0xaa, 0xb8, 0xb4, 0xc9, 0x00, 0x5d },
{ 0xf9, 0x00, 0x13, 0xba, 0xb8, 0xcb, 0x00, 0x4b, 0x00, 0xb3, 0xbc,
0xb4, 0xc7, 0x00, 0x5c, 0x00, 0xac, 0xb8, 0xb4, 0xc8, 0x00, 0x62 },
{ 0xf9, 0x00, 0x13, 0xbb, 0xb7, 0xca, 0x00, 0x4f, 0x00, 0xb4, 0xbb,
0xb3, 0xc7, 0x00, 0x60, 0x00, 0xad, 0xb8, 0xb4, 0xc7, 0x00, 0x67 },
{ 0xf9, 0x00, 0x47, 0xba, 0xb6, 0xca, 0x00, 0x53, 0x00, 0xb5, 0xbb,
0xb3, 0xc6, 0x00, 0x65, 0x00, 0xae, 0xb8, 0xb3, 0xc7, 0x00, 0x6c },
{ 0xf9, 0x00, 0x71, 0xbb, 0xb5, 0xc8, 0x00, 0x57, 0x00, 0xb5, 0xbb,
0xb0, 0xc5, 0x00, 0x6a, 0x00, 0xae, 0xb9, 0xb1, 0xc6, 0x00, 0x70 },
{ 0xf9, 0x00, 0x7b, 0xbb, 0xb4, 0xc8, 0x00, 0x5b, 0x00, 0xb5, 0xba,
0xb1, 0xc4, 0x00, 0x6e, 0x00, 0xae, 0xb9, 0xb0, 0xc5, 0x00, 0x75 },
{ 0xf9, 0x00, 0x82, 0xba, 0xb4, 0xc7, 0x00, 0x5f, 0x00, 0xb5, 0xba,
0xb0, 0xc3, 0x00, 0x72, 0x00, 0xae, 0xb8, 0xb0, 0xc3, 0x00, 0x7a },
{ 0xf9, 0x00, 0x89, 0xba, 0xb3, 0xc8, 0x00, 0x62, 0x00, 0xb6, 0xba,
0xaf, 0xc3, 0x00, 0x76, 0x00, 0xaf, 0xb7, 0xae, 0xc4, 0x00, 0x7e },
{ 0xf9, 0x00, 0x8b, 0xb9, 0xb3, 0xc7, 0x00, 0x65, 0x00, 0xb7, 0xb8,
0xaf, 0xc3, 0x00, 0x7a, 0x00, 0x80, 0xb6, 0xae, 0xc4, 0x00, 0x81 },
{ 0xf9, 0x00, 0x93, 0xba, 0xb3, 0xc5, 0x00, 0x69, 0x00, 0xb8, 0xb9,
0xae, 0xc1, 0x00, 0x7f, 0x00, 0xb0, 0xb6, 0xae, 0xc3, 0x00, 0x85 },
{ 0xf9, 0x00, 0x97, 0xba, 0xb2, 0xc5, 0x00, 0x6c, 0x00, 0xb8, 0xb8,
0xae, 0xc1, 0x00, 0x82, 0x00, 0xb0, 0xb6, 0xae, 0xc2, 0x00, 0x89 },
{ 0xf9, 0x00, 0x9a, 0xba, 0xb1, 0xc4, 0x00, 0x6f, 0x00, 0xb8, 0xb8,
0xad, 0xc0, 0x00, 0x86, 0x00, 0xb0, 0xb7, 0xad, 0xc0, 0x00, 0x8d },
{ 0xf9, 0x00, 0x9c, 0xb9, 0xb0, 0xc4, 0x00, 0x72, 0x00, 0xb8, 0xb8,
0xac, 0xbf, 0x00, 0x8a, 0x00, 0xb0, 0xb6, 0xac, 0xc0, 0x00, 0x91 },
{ 0xf9, 0x00, 0x9e, 0xba, 0xb0, 0xc2, 0x00, 0x75, 0x00, 0xb9, 0xb8,
0xab, 0xbe, 0x00, 0x8e, 0x00, 0xb0, 0xb6, 0xac, 0xbf, 0x00, 0x94 },
{ 0xf9, 0x00, 0xa0, 0xb9, 0xaf, 0xc3, 0x00, 0x77, 0x00, 0xb9, 0xb7,
0xab, 0xbe, 0x00, 0x90, 0x00, 0xb0, 0xb6, 0xab, 0xbf, 0x00, 0x97 },
{ 0xf9, 0x00, 0xa2, 0xb9, 0xaf, 0xc2, 0x00, 0x7a, 0x00, 0xb9, 0xb7,
0xaa, 0xbd, 0x00, 0x94, 0x00, 0xb0, 0xb5, 0xab, 0xbf, 0x00, 0x9a },
{ 0xf9, 0x00, 0xa4, 0xb9, 0xaf, 0xc1, 0x00, 0x7d, 0x00, 0xb9, 0xb6,
0xaa, 0xbb, 0x00, 0x97, 0x00, 0xb1, 0xb5, 0xaa, 0xbf, 0x00, 0x9d },
{ 0xf9, 0x00, 0xa4, 0xb8, 0xb0, 0xbf, 0x00, 0x80, 0x00, 0xb8, 0xb6,
0xaa, 0xbc, 0x00, 0x9a, 0x00, 0xb0, 0xb5, 0xab, 0xbd, 0x00, 0xa0 },
{ 0xf9, 0x00, 0xa8, 0xb8, 0xae, 0xbe, 0x00, 0x84, 0x00, 0xb9, 0xb7,
0xa8, 0xbc, 0x00, 0x9d, 0x00, 0xb2, 0xb5, 0xaa, 0xbc, 0x00, 0xa4 },
{ 0xf9, 0x00, 0xa9, 0xb6, 0xad, 0xbf, 0x00, 0x86, 0x00, 0xb8, 0xb5,
0xa8, 0xbc, 0x00, 0xa0, 0x00, 0xb3, 0xb3, 0xa9, 0xbc, 0x00, 0xa7 },
{ 0xf9, 0x00, 0xa9, 0xb7, 0xae, 0xbd, 0x00, 0x89, 0x00, 0xb7, 0xb6,
0xa8, 0xba, 0x00, 0xa4, 0x00, 0xb1, 0xb4, 0xaa, 0xbb, 0x00, 0xaa },
{ 0xf9, 0x00, 0xa7, 0xb4, 0xae, 0xbf, 0x00, 0x91, 0x00, 0xb2, 0xb4,
0xaa, 0xbb, 0x00, 0xac, 0x00, 0xb3, 0xb1, 0xaa, 0xbc, 0x00, 0xb3 },
struct ld9040 {
struct device *dev;
struct drm_panel panel;
struct regulator_bulk_data supplies[2];
struct gpio_desc *reset_gpio;
u32 power_on_delay;
u32 reset_delay;
struct videomode vm;
u32 width_mm;
u32 height_mm;
int brightness;
/* This field is tested by functions directly accessing bus before
* transfer, transfer is skipped if it is set. In case of transfer
* failure or unexpected response the field is set to error value.
* Such construct allows to eliminate many checks in higher level
* functions.
int error;
static inline struct ld9040 *panel_to_ld9040(struct drm_panel *panel)
return container_of(panel, struct ld9040, panel);
static int ld9040_clear_error(struct ld9040 *ctx)
int ret = ctx->error;
ctx->error = 0;
return ret;
static int ld9040_spi_write_word(struct ld9040 *ctx, u16 data)
struct spi_device *spi = to_spi_device(ctx->dev);
struct spi_transfer xfer = {
.len = 2,
.tx_buf = &data,
struct spi_message msg;
spi_message_add_tail(&xfer, &msg);
return spi_sync(spi, &msg);
static void ld9040_dcs_write(struct ld9040 *ctx, const u8 *data, size_t len)
int ret = 0;
if (ctx->error < 0 || len == 0)
dev_dbg(ctx->dev, "writing dcs seq: %*ph\n", (int)len, data);
ret = ld9040_spi_write_word(ctx, *data);
while (!ret && --len) {
ret = ld9040_spi_write_word(ctx, *data | 0x100);
if (ret) {
dev_err(ctx->dev, "error %d writing dcs seq: %*ph\n", ret,
(int)len, data);
ctx->error = ret;
usleep_range(300, 310);
#define ld9040_dcs_write_seq_static(ctx, seq...) \
static const u8 d[] = { seq };\
ld9040_dcs_write(ctx, d, ARRAY_SIZE(d));\
static void ld9040_brightness_set(struct ld9040 *ctx)
ld9040_dcs_write(ctx, ld9040_gammas[ctx->brightness],
ld9040_dcs_write_seq_static(ctx, MCS_GAMMA_CTRL, 0x02, 0x5a);
static void ld9040_init(struct ld9040 *ctx)
ld9040_dcs_write_seq_static(ctx, MCS_USER_SETTING, 0x5a, 0x5a);
ld9040_dcs_write_seq_static(ctx, MCS_PANEL_CONDITION,
0x05, 0x65, 0x96, 0x71, 0x7d, 0x19, 0x3b, 0x0d,
0x19, 0x7e, 0x0d, 0xe2, 0x00, 0x00, 0x7e, 0x7d,
0x07, 0x07, 0x20, 0x20, 0x20, 0x02, 0x02);
ld9040_dcs_write_seq_static(ctx, MCS_DISPCTL,
0x02, 0x08, 0x08, 0x10, 0x10);
ld9040_dcs_write_seq_static(ctx, MCS_MANPWR, 0x04);
ld9040_dcs_write_seq_static(ctx, MCS_POWER_CTRL,
0x0a, 0x87, 0x25, 0x6a, 0x44, 0x02, 0x88);
ld9040_dcs_write_seq_static(ctx, MCS_ELVSS_ON, 0x0d, 0x00, 0x16);
ld9040_dcs_write_seq_static(ctx, MCS_GTCON, 0x09, 0x00, 0x00);
ld9040_dcs_write_seq_static(ctx, MIPI_DCS_EXIT_SLEEP_MODE);
ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_ON);
static int ld9040_power_on(struct ld9040 *ctx)
int ret;
ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
if (ret < 0)
return ret;
gpiod_set_value(ctx->reset_gpio, 0);
gpiod_set_value(ctx->reset_gpio, 1);
return 0;
static int ld9040_power_off(struct ld9040 *ctx)
return regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
static int ld9040_disable(struct drm_panel *panel)
return 0;
static int ld9040_unprepare(struct drm_panel *panel)
struct ld9040 *ctx = panel_to_ld9040(panel);
ld9040_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_OFF);
ld9040_dcs_write_seq_static(ctx, MIPI_DCS_ENTER_SLEEP_MODE);
return ld9040_power_off(ctx);
static int ld9040_prepare(struct drm_panel *panel)
struct ld9040 *ctx = panel_to_ld9040(panel);
int ret;
ret = ld9040_power_on(ctx);
if (ret < 0)
return ret;
ret = ld9040_clear_error(ctx);
if (ret < 0)
return ret;
static int ld9040_enable(struct drm_panel *panel)
return 0;
static int ld9040_get_modes(struct drm_panel *panel)
struct drm_connector *connector = panel->connector;
struct ld9040 *ctx = panel_to_ld9040(panel);
struct drm_display_mode *mode;
mode = drm_mode_create(connector->dev);
if (!mode) {
DRM_ERROR("failed to create a new display mode\n");
return 0;
drm_display_mode_from_videomode(&ctx->vm, mode);
mode->width_mm = ctx->width_mm;
mode->height_mm = ctx->height_mm;
connector->display_info.width_mm = mode->width_mm;
connector->display_info.height_mm = mode->height_mm;
drm_mode_probed_add(connector, mode);
return 1;
static const struct drm_panel_funcs ld9040_drm_funcs = {
.disable = ld9040_disable,
.unprepare = ld9040_unprepare,
.prepare = ld9040_prepare,
.enable = ld9040_enable,
.get_modes = ld9040_get_modes,
static int ld9040_parse_dt(struct ld9040 *ctx)
struct device *dev = ctx->dev;
struct device_node *np = dev->of_node;
int ret;
ret = of_get_videomode(np, &ctx->vm, 0);
if (ret < 0)
return ret;
of_property_read_u32(np, "power-on-delay", &ctx->power_on_delay);
of_property_read_u32(np, "reset-delay", &ctx->reset_delay);
of_property_read_u32(np, "panel-width-mm", &ctx->width_mm);
of_property_read_u32(np, "panel-height-mm", &ctx->height_mm);
return 0;
static int ld9040_probe(struct spi_device *spi)
struct device *dev = &spi->dev;
struct ld9040 *ctx;
int ret;
ctx = devm_kzalloc(dev, sizeof(struct ld9040), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
spi_set_drvdata(spi, ctx);
ctx->dev = dev;
ctx->brightness = ARRAY_SIZE(ld9040_gammas) - 1;
ret = ld9040_parse_dt(ctx);
if (ret < 0)
return ret;
ctx->supplies[0].supply = "vdd3";
ctx->supplies[1].supply = "vci";
ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ctx->supplies),
if (ret < 0)
return ret;
ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
if (IS_ERR(ctx->reset_gpio)) {
dev_err(dev, "cannot get reset-gpios %ld\n",
return PTR_ERR(ctx->reset_gpio);
spi->bits_per_word = 9;
ret = spi_setup(spi);
if (ret < 0) {
dev_err(dev, "spi setup failed.\n");
return ret;
ctx-> = dev;
ctx->panel.funcs = &ld9040_drm_funcs;
return drm_panel_add(&ctx->panel);
static int ld9040_remove(struct spi_device *spi)
struct ld9040 *ctx = spi_get_drvdata(spi);
return 0;
static const struct of_device_id ld9040_of_match[] = {
{ .compatible = "samsung,ld9040" },
{ }
MODULE_DEVICE_TABLE(of, ld9040_of_match);
static struct spi_driver ld9040_driver = {
.probe = ld9040_probe,
.remove = ld9040_remove,
.driver = {
.name = "panel-samsung-ld9040",
.of_match_table = ld9040_of_match,
MODULE_AUTHOR("Andrzej Hajda <>");