Re: [PATCH v3 2/2] drm/panel: Add driver for Samsung S6E63M0 panel

On 02.02.2019 15:27, Paweł Chmiel wrote:

This patch adds Samsung S6E63M0 AMOLED LCD panel driver, connected over spi. It's based on already removed, non dt s6e63m0 driver and panel-samsung-ld9040. It can be found for example in some of Samsung Aries based phones.

Signed-off-by: Paweł Chmiel pawel.mikolaj.chmiel@gmail.com Reviewed-by: Sam Ravnborg sam@ravnborg.org

---

Changes from v2:

• VIDEOMODE_HELPERS is not needed in Kconfig
• Added help text to Kconfig
• Remove unneeded videomode includes/fields
• Add sentinel comment in s6e63m0_of_match struct
• Handle errors during registration of backlight device. We shouldn't register panel if we fail to register backlight device
• Added Reviewed-by

Changes from v1:

• Correct order of Kconfig/Makefile entry
• Fix SPDX tag, so it matches value of MODULE_LICENSE
• Remove inclusion of drmP.h
• Fix code formatting
• Use DRM_DEV_ERROR/DEBUG
• Extract hardcoded values
• Remove possibility to change gamma through sysfs, leaving only one gamma table values
• Fix reset_gpio handling, so it'll be asserted in power_on and deasserted in power_off. Also do it before turning voltage on.
• Disable backlight and enter sleep mode in disable callback. Previously it was done in unprepare
• Enable display and backlight in enable callback. Previously it was done in prepare
• Hardcode display timings and delays. Previously they were readed from device tree
• We're using SPDX, so we don't need to have license body
• Use MIPI_DCS_EXIT_SLEEP_MODE and MIPI_DCS_SET_DISPLAY_ON
• Rename MAX_GAMMA_LEVEL to NUM_GAMMA_LEVELS
• Ommit get_brightness callback
• Use backlight_enable/disable API, like it's done in other panel drivers (for example panel-simple)
• Make set_brightness called only from backlight api, like it's done in other panel drivers (for example panel-simple).
• Reset gpio should be set to GPIOD_OUT_HIGH. It's declared as active low in device tree
• Don't call power_off in remove callback

---

drivers/gpu/drm/panel/Kconfig | 9 + drivers/gpu/drm/panel/Makefile | 1 + drivers/gpu/drm/panel/panel-samsung-s6e63m0.c | 517 ++++++++++++++++++ 3 files changed, 527 insertions(+) create mode 100644 drivers/gpu/drm/panel/panel-samsung-s6e63m0.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig index 3f3537719beb..45e9ab4b7857 100644 --- a/drivers/gpu/drm/panel/Kconfig +++ b/drivers/gpu/drm/panel/Kconfig @@ -158,6 +158,15 @@ config DRM_PANEL_SAMSUNG_S6E63J0X03 depends on BACKLIGHT_CLASS_DEVICE select VIDEOMODE_HELPERS

+config DRM_PANEL_SAMSUNG_S6E63M0

• tristate "Samsung S6E63M0 RGB/SPI panel"
• depends on OF
• depends on SPI
• depends on BACKLIGHT_CLASS_DEVICE
• help

•  Say Y here if you want to enable support for Samsung s6e63m0
  

•  AMOLED LCD panel.
  

config DRM_PANEL_SAMSUNG_S6E8AA0 tristate "Samsung S6E8AA0 DSI video mode panel" depends on OF diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile index 4396658a7996..4507a2d253ac 100644 --- a/drivers/gpu/drm/panel/Makefile +++ b/drivers/gpu/drm/panel/Makefile @@ -16,6 +16,7 @@ obj-$(CONFIG_DRM_PANEL_SAMSUNG_LD9040) += panel-samsung-ld9040.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6D16D0) += panel-samsung-s6d16d0.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E3HA2) += panel-samsung-s6e3ha2.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63J0X03) += panel-samsung-s6e63j0x03.o +obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E63M0) += panel-samsung-s6e63m0.o obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8AA0) += panel-samsung-s6e8aa0.o obj-$(CONFIG_DRM_PANEL_SEIKO_43WVF1G) += panel-seiko-43wvf1g.o obj-$(CONFIG_DRM_PANEL_SHARP_LQ101R1SX01) += panel-sharp-lq101r1sx01.o diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c new file mode 100644 index 000000000000..4312aa3e4386 --- /dev/null +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63m0.c @@ -0,0 +1,517 @@ +// SPDX-License-Identifier: GPL-2.0 +/*

• • S6E63M0 AMOLED LCD drm_panel driver.
• • Copyright (C) 2019 Paweł Chmiel pawel.mikolaj.chmiel@gmail.com
• • Derived from drivers/gpu/drm/panel-samsung-ld9040.c
• • Andrzej Hajda a.hajda@samsung.com
• */

+#include <drm/drm_modes.h> +#include <drm/drm_panel.h> +#include <drm/drm_print.h>

+#include <linux/backlight.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> +#include <linux/spi/spi.h>

+#include <video/mipi_display.h>

+/* Manufacturer Command Set */ +#define MCS_ELVSS_ON 0xb1 +#define MCS_ACL_CTRL 0xc0 +#define MCS_DISPLAY_CONDITION 0xf2 +#define MCS_ETC_CONDITION 0xf6 +#define MCS_PANEL_CONDITION 0xF8 +#define MCS_GAMMA_CTRL 0xfa

+#define NUM_GAMMA_LEVELS 11 +#define GAMMA_TABLE_COUNT 23

+#define DATA_MASK 0x100

+#define MAX_BRIGHTNESS (NUM_GAMMA_LEVELS - 1)

+/* array of gamma tables for gamma value 2.2 */ +static u8 const s6e63m0_gamma_22[NUM_GAMMA_LEVELS][GAMMA_TABLE_COUNT] = {

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x78, 0xEC, 0x3D, 0xC8,
  

•  0xC2, 0xB6, 0xC4, 0xC7, 0xB6, 0xD5, 0xD7,
  

•  0xCC, 0x00, 0x39, 0x00, 0x36, 0x00, 0x51 },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x73, 0x4A, 0x3D, 0xC0,
  

•  0xC2, 0xB1, 0xBB, 0xBE, 0xAC, 0xCE, 0xCF,
  

•  0xC5, 0x00, 0x5D, 0x00, 0x5E, 0x00, 0x82 },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x70, 0x51, 0x3E, 0xBF,
  

•  0xC1, 0xAF, 0xB9, 0xBC, 0xAB, 0xCC, 0xCC,
  

•  0xC2, 0x00, 0x65, 0x00, 0x67, 0x00, 0x8D },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x6C, 0x54, 0x3A, 0xBC,
  

•  0xBF, 0xAC, 0xB7, 0xBB, 0xA9, 0xC9, 0xC9,
  

•  0xBE, 0x00, 0x71, 0x00, 0x73, 0x00, 0x9E },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x69, 0x54, 0x37, 0xBB,
  

•  0xBE, 0xAC, 0xB4, 0xB7, 0xA6, 0xC7, 0xC8,
  

•  0xBC, 0x00, 0x7B, 0x00, 0x7E, 0x00, 0xAB },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x66, 0x55, 0x34, 0xBA,
  

•  0xBD, 0xAB, 0xB1, 0xB5, 0xA3, 0xC5, 0xC6,
  

•  0xB9, 0x00, 0x85, 0x00, 0x88, 0x00, 0xBA },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x63, 0x53, 0x31, 0xB8,
  

•  0xBC, 0xA9, 0xB0, 0xB5, 0xA2, 0xC4, 0xC4,
  

•  0xB8, 0x00, 0x8B, 0x00, 0x8E, 0x00, 0xC2 },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x62, 0x54, 0x30, 0xB9,
  

•  0xBB, 0xA9, 0xB0, 0xB3, 0xA1, 0xC1, 0xC3,
  

•  0xB7, 0x00, 0x91, 0x00, 0x95, 0x00, 0xDA },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x66, 0x58, 0x34, 0xB6,
  

•  0xBA, 0xA7, 0xAF, 0xB3, 0xA0, 0xC1, 0xC2,
  

•  0xB7, 0x00, 0x97, 0x00, 0x9A, 0x00, 0xD1 },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x64, 0x56, 0x33, 0xB6,
  

•  0xBA, 0xA8, 0xAC, 0xB1, 0x9D, 0xC1, 0xC1,
  

•  0xB7, 0x00, 0x9C, 0x00, 0x9F, 0x00, 0xD6 },
  

• { MCS_GAMMA_CTRL, 0x00,

•  0x18, 0x08, 0x24, 0x5f, 0x50, 0x2d, 0xB6,
  

•  0xB9, 0xA7, 0xAd, 0xB1, 0x9f, 0xbe, 0xC0,
  

•  0xB5, 0x00, 0xa0, 0x00, 0xa4, 0x00, 0xdb },
  

+};

+struct s6e63m0 {

• struct device *dev;
• struct drm_panel panel;
• struct backlight_device *bl_dev;
• struct regulator_bulk_data supplies[2];
• struct gpio_desc *reset_gpio;
• bool prepared;
• bool enabled;
• /*

• * 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 const struct drm_display_mode default_mode = {

• .clock = 25628,
• .hdisplay = 480,
• .hsync_start = 480 + 16,
• .hsync_end = 480 + 16 + 2,
• .htotal = 480 + 16 + 2 + 16,
• .vdisplay = 800,
• .vsync_start = 800 + 28,
• .vsync_end = 800 + 28 + 2,
• .vtotal = 800 + 28 + 2 + 1,
• .vrefresh = 60,
• .width_mm = 53,
• .height_mm = 89,
• .flags = DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC,

+};

+static inline struct s6e63m0 *panel_to_s6e63m0(struct drm_panel *panel) +{

• return container_of(panel, struct s6e63m0, panel);

+}

+static int s6e63m0_clear_error(struct s6e63m0 *ctx) +{

• int ret = ctx->error;
• ctx->error = 0;
• return ret;

+}

+static int s6e63m0_spi_write_word(struct s6e63m0 *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_init(&msg);
• spi_message_add_tail(&xfer, &msg);
• return spi_sync(spi, &msg);

+}

+static void s6e63m0_dcs_write(struct s6e63m0 *ctx, const u8 *data, size_t len) +{

• int ret = 0;
• if (ctx->error < 0 || len == 0)

• return;
  

• DRM_DEV_DEBUG(ctx->dev, "writing dcs seq: %*ph\n", (int)len, data);
• ret = s6e63m0_spi_write_word(ctx, *data);
• while (!ret && --len) {

• ++data;
  

• ret = s6e63m0_spi_write_word(ctx, *data | DATA_MASK);
  

• }
• if (ret) {

• DRM_DEV_ERROR(ctx->dev, "error %d writing dcs seq: %*ph\n", ret,
  

• 	      (int)len, data);
  

• ctx->error = ret;
  

• }
• usleep_range(300, 310);

+}

+#define s6e63m0_dcs_write_seq_static(ctx, seq ...) \

• ({ \

• static const u8 d[] = { seq }; \
  

• s6e63m0_dcs_write(ctx, d, ARRAY_SIZE(d)); \
  

• })

+static void s6e63m0_brightness_set(struct s6e63m0 *ctx) +{

• int brightness = ctx->bl_dev->props.brightness;
• /* disable and set new gamma */
• s6e63m0_dcs_write(ctx, s6e63m0_gamma_22[brightness],

• 	  ARRAY_SIZE(s6e63m0_gamma_22[brightness]));
  

• /* update gamma table. */
• s6e63m0_dcs_write_seq_static(ctx, MCS_GAMMA_CTRL, 0x01);

+}

I guess you can squash this callback into s6e63m0_set_brightness. Moreover you performs transfer here unconditionally, regardless of panel power state, it will fail when drm device is disabled (using echo 255

/sys/class/backlight/...) - panel is also disabled - making transfer to

disabled panel by panel driver looks odd, moreover it could be little bit racy. But in practice it could work.

Moreover I do not see usage of backlight_properties.power, backlight_properties.state, but I do not understand how exactly backlight interface should work, if someone can point out to proper docs/usage of backlight API I will be glad.

+static void s6e63m0_init(struct s6e63m0 *ctx) +{

• s6e63m0_dcs_write_seq_static(ctx, MCS_PANEL_CONDITION,

• 		     0x01, 0x27, 0x27, 0x07, 0x07, 0x54, 0x9f,
  

• 		     0x63, 0x86, 0x1a, 0x33, 0x0d, 0x00, 0x00);
  

• s6e63m0_dcs_write_seq_static(ctx, MCS_DISPLAY_CONDITION,

• 		     0x02, 0x03, 0x1c, 0x10, 0x10);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xf7,

• 		     0x03, 0x00, 0x00);
  

• s6e63m0_dcs_write_seq_static(ctx, MCS_GAMMA_CTRL,

• 		     0x00, 0x18, 0x08, 0x24, 0x64, 0x56, 0x33,
  

• 		     0xb6, 0xba, 0xa8, 0xac, 0xb1, 0x9d, 0xc1,
  

• 		     0xc1, 0xb7, 0x00, 0x9c, 0x00, 0x9f, 0x00,
  

• 		     0xd6);
  

• s6e63m0_dcs_write_seq_static(ctx, MCS_GAMMA_CTRL,

• 		     0x01);
  

• s6e63m0_dcs_write_seq_static(ctx, MCS_ETC_CONDITION,

• 		     0x00, 0x8c, 0x07);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xb3,

• 		     0xc);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xb5,

• 		     0x2c, 0x12, 0x0c, 0x0a, 0x10, 0x0e, 0x17,
  

• 		     0x13, 0x1f, 0x1a, 0x2a, 0x24, 0x1f, 0x1b,
  

• 		     0x1a, 0x17, 0x2b, 0x26, 0x22, 0x20, 0x3a,
  

• 		     0x34, 0x30, 0x2c, 0x29, 0x26, 0x25, 0x23,
  

• 		     0x21, 0x20, 0x1e, 0x1e);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xb6,

• 		     0x00, 0x00, 0x11, 0x22, 0x33, 0x44, 0x44,
  

• 		     0x44, 0x55, 0x55, 0x66, 0x66, 0x66, 0x66,
  

• 		     0x66, 0x66);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xb7,

• 		     0x2c, 0x12, 0x0c, 0x0a, 0x10, 0x0e, 0x17,
  

• 		     0x13, 0x1f, 0x1a, 0x2a, 0x24, 0x1f, 0x1b,
  

• 		     0x1a, 0x17, 0x2b, 0x26, 0x22, 0x20, 0x3a,
  

• 		     0x34, 0x30, 0x2c, 0x29, 0x26, 0x25, 0x23,
  

• 		     0x21, 0x20, 0x1e, 0x1e, 0x00, 0x00, 0x11,
  

• 		     0x22, 0x33, 0x44, 0x44, 0x44, 0x55, 0x55,
  

• 		     0x66, 0x66, 0x66, 0x66, 0x66, 0x66);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xb9,

• 		     0x2c, 0x12, 0x0c, 0x0a, 0x10, 0x0e, 0x17,
  

• 		     0x13, 0x1f, 0x1a, 0x2a, 0x24, 0x1f, 0x1b,
  

• 		     0x1a, 0x17, 0x2b, 0x26, 0x22, 0x20, 0x3a,
  

• 		     0x34, 0x30, 0x2c, 0x29, 0x26, 0x25, 0x23,
  

• 		     0x21, 0x20, 0x1e, 0x1e);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xba,

• 		     0x00, 0x00, 0x11, 0x22, 0x33, 0x44, 0x44,
  

• 		     0x44, 0x55, 0x55, 0x66, 0x66, 0x66, 0x66,
  

• 		     0x66, 0x66);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xc1,

• 		     0x4d, 0x96, 0x1d, 0x00, 0x00, 0x01, 0xdf,
  

• 		     0x00, 0x00, 0x03, 0x1f, 0x00, 0x00, 0x00,
  

• 		     0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0x06,
  

• 		     0x09, 0x0d, 0x0f, 0x12, 0x15, 0x18);
  

• s6e63m0_dcs_write_seq_static(ctx, 0xb2,

• 		     0x10, 0x10, 0x0b, 0x05);
  

• s6e63m0_dcs_write_seq_static(ctx, MCS_ACL_CTRL,

• 		     0x01);
  

• s6e63m0_dcs_write_seq_static(ctx, MCS_ELVSS_ON,

• 		     0x0b);
  

• s6e63m0_dcs_write_seq_static(ctx, MIPI_DCS_EXIT_SLEEP_MODE);

+}

+static int s6e63m0_power_on(struct s6e63m0 *ctx) +{

• int ret;
• gpiod_set_value(ctx->reset_gpio, 0);
• msleep(120);
• ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
• if (ret < 0)

• return ret;
  

Are you sure gpios before regulators, from my experience usually it is reverse.

• msleep(25);
• return 0;

+}

+static int s6e63m0_power_off(struct s6e63m0 *ctx) +{

• int ret;
• ret = regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
• if (ret < 0)

• return ret;
  

• gpiod_set_value(ctx->reset_gpio, 1);

Ditto.

• msleep(120);

What is the point of this msleep?

I guess, the answer for above comments can be difficult, since datasheet is not available, so if you just followed vendor code please feel free to add:

Reviewed-by: Andrzej Hajda a.hajda@samsung.com

--

Regards Andrzej

• return 0;

+}

+static int s6e63m0_disable(struct drm_panel *panel) +{

• struct s6e63m0 *ctx = panel_to_s6e63m0(panel);
• if (!ctx->enabled)

• return 0;
  

• backlight_disable(ctx->bl_dev);
• s6e63m0_dcs_write_seq_static(ctx, MIPI_DCS_ENTER_SLEEP_MODE);
• msleep(200);
• ctx->enabled = false;
• return 0;

+}

+static int s6e63m0_unprepare(struct drm_panel *panel) +{

• struct s6e63m0 *ctx = panel_to_s6e63m0(panel);
• int ret;
• if (!ctx->prepared)

• return 0;
  

• s6e63m0_clear_error(ctx);
• ret = s6e63m0_power_off(ctx);
• if (ret < 0)

• return ret;
  

• ctx->prepared = false;
• return 0;

+}

+static int s6e63m0_prepare(struct drm_panel *panel) +{

• struct s6e63m0 *ctx = panel_to_s6e63m0(panel);
• int ret;
• if (ctx->prepared)

• return 0;
  

• ret = s6e63m0_power_on(ctx);
• if (ret < 0)

• return ret;
  

• s6e63m0_init(ctx);
• ret = s6e63m0_clear_error(ctx);
• if (ret < 0)

• s6e63m0_unprepare(panel);
  

• ctx->prepared = true;
• return ret;

+}

+static int s6e63m0_enable(struct drm_panel *panel) +{

• struct s6e63m0 *ctx = panel_to_s6e63m0(panel);
• if (ctx->enabled)

• return 0;
  

• s6e63m0_dcs_write_seq_static(ctx, MIPI_DCS_SET_DISPLAY_ON);
• backlight_enable(ctx->bl_dev);
• ctx->enabled = true;
• return 0;

+}

+static int s6e63m0_get_modes(struct drm_panel *panel) +{

• struct drm_connector *connector = panel->connector;
• struct drm_display_mode *mode;
• mode = drm_mode_duplicate(panel->drm, &default_mode);
• if (!mode) {

• DRM_ERROR("failed to add mode %ux%ux@%u\n",
  

• 	  default_mode.hdisplay, default_mode.vdisplay,
  

• 	  default_mode.vrefresh);
  

• return -ENOMEM;
  

• }
• drm_mode_set_name(mode);
• mode->type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
• drm_mode_probed_add(connector, mode);
• return 1;

+}

+static const struct drm_panel_funcs s6e63m0_drm_funcs = {

• .disable = s6e63m0_disable,
• .unprepare = s6e63m0_unprepare,
• .prepare = s6e63m0_prepare,
• .enable = s6e63m0_enable,
• .get_modes = s6e63m0_get_modes,

+};

+static int s6e63m0_set_brightness(struct backlight_device *bd) +{

• struct s6e63m0 *ctx = bl_get_data(bd);
• s6e63m0_brightness_set(ctx);
• return s6e63m0_clear_error(ctx);

+}

+static const struct backlight_ops s6e63m0_backlight_ops = {

• .update_status = s6e63m0_set_brightness,

+};

+static int s6e63m0_backlight_register(struct s6e63m0 *ctx) +{

• struct backlight_properties props = {

• .type		= BACKLIGHT_RAW,
  

• .brightness	= MAX_BRIGHTNESS,
  

• .max_brightness = MAX_BRIGHTNESS
  

• };
• struct device *dev = ctx->dev;
• int ret = 0;
• ctx->bl_dev = devm_backlight_device_register(dev, "panel", dev, ctx,

• 				     &s6e63m0_backlight_ops,
  

• 				     &props);
  

• if (IS_ERR(ctx->bl_dev)) {

• ret = PTR_ERR(ctx->bl_dev);
  

• DRM_DEV_ERROR(dev, "error registering backlight device (%d)\n",
  

• 	      ret);
  

• }
• return ret;

+}

+static int s6e63m0_probe(struct spi_device *spi) +{

• struct device *dev = &spi->dev;
• struct s6e63m0 *ctx;
• int ret;
• ctx = devm_kzalloc(dev, sizeof(struct s6e63m0), GFP_KERNEL);
• if (!ctx)

• return -ENOMEM;
  

• spi_set_drvdata(spi, ctx);
• ctx->dev = dev;
• ctx->enabled = false;
• ctx->prepared = false;
• ctx->supplies[0].supply = "vdd3";
• ctx->supplies[1].supply = "vci";
• ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ctx->supplies),

• 		      ctx->supplies);
  

• if (ret < 0) {

• DRM_DEV_ERROR(dev, "failed to get regulators: %d\n", ret);
  

• return ret;
  

• }
• ctx->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
• if (IS_ERR(ctx->reset_gpio)) {

• DRM_DEV_ERROR(dev, "cannot get reset-gpios %ld\n",
  

• 	      PTR_ERR(ctx->reset_gpio));
  

• return PTR_ERR(ctx->reset_gpio);
  

• }
• spi->bits_per_word = 9;
• spi->mode = SPI_MODE_3;
• ret = spi_setup(spi);
• if (ret < 0) {

• DRM_DEV_ERROR(dev, "spi setup failed.\n");
  

• return ret;
  

• }
• drm_panel_init(&ctx->panel);
• ctx->panel.dev = dev;
• ctx->panel.funcs = &s6e63m0_drm_funcs;
• ret = s6e63m0_backlight_register(ctx);
• if (ret < 0)

• return ret;
  

• return drm_panel_add(&ctx->panel);

+}

+static int s6e63m0_remove(struct spi_device *spi) +{

• struct s6e63m0 *ctx = spi_get_drvdata(spi);
• drm_panel_remove(&ctx->panel);
• return 0;

+}

+static const struct of_device_id s6e63m0_of_match[] = {

• { .compatible = "samsung,s6e63m0" },
• { /* sentinel */ }

+}; +MODULE_DEVICE_TABLE(of, s6e63m0_of_match);

+static struct spi_driver s6e63m0_driver = {

• .probe = s6e63m0_probe,
• .remove = s6e63m0_remove,
• .driver = {

• .name		= "panel-samsung-s6e63m0",
  

• .of_match_table = s6e63m0_of_match,
  

• },

+}; +module_spi_driver(s6e63m0_driver);

+MODULE_AUTHOR("Paweł Chmiel pawel.mikolaj.chmiel@gmail.com"); +MODULE_DESCRIPTION("s6e63m0 LCD Driver"); +MODULE_LICENSE("GPL v2");