--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Panel driver for the WideChips WS2401 480x800 DPI RGB panel, used in
+ * the Samsung Mobile Display (SMD) LMS380KF01.
+ * Found in the Samsung Galaxy Ace 2 GT-I8160 mobile phone.
+ * Linus Walleij <linus.walleij@linaro.org>
+ * Inspired by code and know-how in the vendor driver by Gareth Phillips.
+ */
+#include <drm/drm_mipi_dbi.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/media-bus-format.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
+
+#include <video/mipi_display.h>
+
+#define WS2401_RESCTL 0xb8 /* Resolution select control */
+#define WS2401_PSMPS 0xbd /* SMPS positive control */
+#define WS2401_NSMPS 0xbe /* SMPS negative control */
+#define WS2401_SMPS 0xbf
+#define WS2401_BCMODE 0xc1 /* Backlight control mode */
+#define WS2401_WRBLCTL 0xc3 /* Backlight control */
+#define WS2401_WRDISBV 0xc4 /* Write manual brightness */
+#define WS2401_WRCTRLD 0xc6 /* Write BL control */
+#define WS2401_WRMIE 0xc7 /* Write MIE mode */
+#define WS2401_READ_ID1 0xda /* Read panel ID 1 */
+#define WS2401_READ_ID2 0xdb /* Read panel ID 2 */
+#define WS2401_READ_ID3 0xdc /* Read panel ID 3 */
+#define WS2401_GAMMA_R1 0xe7 /* Gamma red 1 */
+#define WS2401_GAMMA_G1 0xe8 /* Gamma green 1 */
+#define WS2401_GAMMA_B1 0xe9 /* Gamma blue 1 */
+#define WS2401_GAMMA_R2 0xea /* Gamma red 2 */
+#define WS2401_GAMMA_G2 0xeb /* Gamma green 2 */
+#define WS2401_GAMMA_B2 0xec /* Gamma blue 2 */
+#define WS2401_PASSWD1 0xf0 /* Password command for level 2 */
+#define WS2401_DISCTL 0xf2 /* Display control */
+#define WS2401_PWRCTL 0xf3 /* Power control */
+#define WS2401_VCOMCTL 0xf4 /* VCOM control */
+#define WS2401_SRCCTL 0xf5 /* Source control */
+#define WS2401_PANELCTL 0xf6 /* Panel control */
+
+static const u8 ws2401_dbi_read_commands[] = {
+ WS2401_READ_ID1,
+ WS2401_READ_ID2,
+ WS2401_READ_ID3,
+ 0, /* sentinel */
+};
+
+/**
+ * struct ws2401 - state container for a panel controlled by the WS2401
+ * controller
+ */
+struct ws2401 {
+ /** @dev: the container device */
+ struct device *dev;
+ /** @dbi: the DBI bus abstraction handle */
+ struct mipi_dbi dbi;
+ /** @panel: the DRM panel instance for this device */
+ struct drm_panel panel;
+ /** @width: the width of this panel in mm */
+ u32 width;
+ /** @height: the height of this panel in mm */
+ u32 height;
+ /** @reset: reset GPIO line */
+ struct gpio_desc *reset;
+ /** @regulators: VCCIO and VIO supply regulators */
+ struct regulator_bulk_data regulators[2];
+ /** @internal_bl: If using internal backlight */
+ bool internal_bl;
+};
+
+static const struct drm_display_mode lms380kf01_480_800_mode = {
+ /*
+ * The vendor driver states that the "SMD panel" has a clock
+ * frequency of 49920000 Hz / 2 = 24960000 Hz.
+ */
+ .clock = 24960,
+ .hdisplay = 480,
+ .hsync_start = 480 + 8,
+ .hsync_end = 480 + 8 + 10,
+ .htotal = 480 + 8 + 10 + 8,
+ .vdisplay = 800,
+ .vsync_start = 800 + 8,
+ .vsync_end = 800 + 8 + 2,
+ .vtotal = 800 + 8 + 2 + 18,
+ .width_mm = 50,
+ .height_mm = 84,
+ .flags = DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC,
+};
+
+static inline struct ws2401 *to_ws2401(struct drm_panel *panel)
+{
+ return container_of(panel, struct ws2401, panel);
+}
+
+static void ws2401_read_mtp_id(struct ws2401 *ws)
+{
+ struct mipi_dbi *dbi = &ws->dbi;
+ u8 id1, id2, id3;
+ int ret;
+
+ ret = mipi_dbi_command_read(dbi, WS2401_READ_ID1, &id1);
+ if (ret) {
+ dev_err(ws->dev, "unable to read MTP ID 1\n");
+ return;
+ }
+ ret = mipi_dbi_command_read(dbi, WS2401_READ_ID2, &id2);
+ if (ret) {
+ dev_err(ws->dev, "unable to read MTP ID 2\n");
+ return;
+ }
+ ret = mipi_dbi_command_read(dbi, WS2401_READ_ID3, &id3);
+ if (ret) {
+ dev_err(ws->dev, "unable to read MTP ID 3\n");
+ return;
+ }
+ dev_info(ws->dev, "MTP ID: %02x %02x %02x\n", id1, id2, id3);
+}
+
+static int ws2401_power_on(struct ws2401 *ws)
+{
+ struct mipi_dbi *dbi = &ws->dbi;
+ int ret;
+
+ /* Power up */
+ ret = regulator_bulk_enable(ARRAY_SIZE(ws->regulators),
+ ws->regulators);
+ if (ret) {
+ dev_err(ws->dev, "failed to enable regulators: %d\n", ret);
+ return ret;
+ }
+ msleep(10);
+
+ /* Assert reset >=1 ms */
+ gpiod_set_value_cansleep(ws->reset, 1);
+ usleep_range(1000, 5000);
+ /* De-assert reset */
+ gpiod_set_value_cansleep(ws->reset, 0);
+ /* Wait >= 10 ms */
+ msleep(10);
+ dev_dbg(ws->dev, "de-asserted RESET\n");
+
+ /*
+ * Exit sleep mode and initialize display - some hammering is
+ * necessary.
+ */
+ mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
+ mipi_dbi_command(dbi, MIPI_DCS_EXIT_SLEEP_MODE);
+ msleep(50);
+
+ /* Magic to unlock level 2 control of the display */
+ mipi_dbi_command(dbi, WS2401_PASSWD1, 0x5a, 0x5a);
+ /* Configure resolution to 480RGBx800 */
+ mipi_dbi_command(dbi, WS2401_RESCTL, 0x12);
+ /* Set addressing mode Flip V(d0), Flip H(d1) RGB/BGR(d3) */
+ mipi_dbi_command(dbi, MIPI_DCS_SET_ADDRESS_MODE, 0x01);
+ /* Set pixel format: 24 bpp */
+ mipi_dbi_command(dbi, MIPI_DCS_SET_PIXEL_FORMAT, 0x70);
+ mipi_dbi_command(dbi, WS2401_SMPS, 0x00, 0x0f);
+ mipi_dbi_command(dbi, WS2401_PSMPS, 0x06, 0x03, /* DDVDH: 4.6v */
+ 0x7e, 0x03, 0x12, 0x37);
+ mipi_dbi_command(dbi, WS2401_NSMPS, 0x06, 0x03, /* DDVDH: -4.6v */
+ 0x7e, 0x02, 0x15, 0x37);
+ mipi_dbi_command(dbi, WS2401_SMPS, 0x02, 0x0f);
+ mipi_dbi_command(dbi, WS2401_PWRCTL, 0x10, 0xA9, 0x00, 0x01, 0x44,
+ 0xb4, /* VGH:16.1v, VGL:-13.8v */
+ 0x50, /* GREFP:4.2v (default) */
+ 0x50, /* GREFN:-4.2v (default) */
+ 0x00,
+ 0x44); /* VOUTL:-10v (default) */
+ mipi_dbi_command(dbi, WS2401_DISCTL, 0x01, 0x00, 0x00, 0x00, 0x14,
+ 0x16);
+ mipi_dbi_command(dbi, WS2401_VCOMCTL, 0x30, 0x53, 0x53);
+ mipi_dbi_command(dbi, WS2401_SRCCTL, 0x03, 0x0C, 0x00, 0x00, 0x00,
+ 0x01, /* 2 dot inversion */
+ 0x01, 0x06, 0x03);
+ mipi_dbi_command(dbi, WS2401_PANELCTL, 0x14, 0x00, 0x80, 0x00);
+ mipi_dbi_command(dbi, WS2401_WRMIE, 0x01);
+
+ /* Set up gamma, probably these are P-gamma and N-gamma for each color */
+ mipi_dbi_command(dbi, WS2401_GAMMA_R1, 0x00,
+ 0x5b, 0x42, 0x41, 0x3f, 0x42, 0x3d, 0x38, 0x2e,
+ 0x2b, 0x2a, 0x27, 0x22, 0x27, 0x0f, 0x00, 0x00);
+ mipi_dbi_command(dbi, WS2401_GAMMA_R2, 0x00,
+ 0x5b, 0x42, 0x41, 0x3f, 0x42, 0x3d, 0x38, 0x2e,
+ 0x2b, 0x2a, 0x27, 0x22, 0x27, 0x0f, 0x00, 0x00);
+ mipi_dbi_command(dbi, WS2401_GAMMA_G1, 0x00,
+ 0x59, 0x40, 0x3f, 0x3e, 0x41, 0x3d, 0x39, 0x2f,
+ 0x2c, 0x2b, 0x29, 0x25, 0x29, 0x19, 0x08, 0x00);
+ mipi_dbi_command(dbi, WS2401_GAMMA_G2, 0x00,
+ 0x59, 0x40, 0x3f, 0x3e, 0x41, 0x3d, 0x39, 0x2f,
+ 0x2c, 0x2b, 0x29, 0x25, 0x29, 0x19, 0x08, 0x00);
+ mipi_dbi_command(dbi, WS2401_GAMMA_B1, 0x00,
+ 0x57, 0x3b, 0x3a, 0x3b, 0x3f, 0x3b, 0x38, 0x27,
+ 0x38, 0x2a, 0x26, 0x22, 0x34, 0x0c, 0x09, 0x00);
+ mipi_dbi_command(dbi, WS2401_GAMMA_B2, 0x00,
+ 0x57, 0x3b, 0x3a, 0x3b, 0x3f, 0x3b, 0x38, 0x27,
+ 0x38, 0x2a, 0x26, 0x22, 0x34, 0x0c, 0x09, 0x00);
+
+ if (ws->internal_bl) {
+ mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x2c);
+ } else {
+ mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x00);
+ /*
+ * When not using internal backlight we do not need any further
+ * L2 accesses to the panel so we close the door on our way out.
+ * Otherwise we need to leave the L2 door open.
+ */
+ mipi_dbi_command(dbi, WS2401_PASSWD1, 0xa5, 0xa5);
+ }
+
+ return 0;
+}
+
+static int ws2401_power_off(struct ws2401 *ws)
+{
+ /* Go into RESET and disable regulators */
+ gpiod_set_value_cansleep(ws->reset, 1);
+ return regulator_bulk_disable(ARRAY_SIZE(ws->regulators),
+ ws->regulators);
+}
+
+static int ws2401_unprepare(struct drm_panel *panel)
+{
+ struct ws2401 *ws = to_ws2401(panel);
+ struct mipi_dbi *dbi = &ws->dbi;
+
+ /* Make sure we disable backlight, if any */
+ if (ws->internal_bl)
+ mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x00);
+ mipi_dbi_command(dbi, MIPI_DCS_ENTER_SLEEP_MODE);
+ msleep(120);
+ return ws2401_power_off(to_ws2401(panel));
+}
+
+static int ws2401_disable(struct drm_panel *panel)
+{
+ struct ws2401 *ws = to_ws2401(panel);
+ struct mipi_dbi *dbi = &ws->dbi;
+
+ mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_OFF);
+ msleep(25);
+
+ return 0;
+}
+
+static int ws2401_prepare(struct drm_panel *panel)
+{
+ return ws2401_power_on(to_ws2401(panel));
+}
+
+static int ws2401_enable(struct drm_panel *panel)
+{
+ struct ws2401 *ws = to_ws2401(panel);
+ struct mipi_dbi *dbi = &ws->dbi;
+
+ mipi_dbi_command(dbi, MIPI_DCS_SET_DISPLAY_ON);
+
+ return 0;
+}
+
+/**
+ * ws2401_get_modes() - return the mode
+ * @panel: the panel to get the mode for
+ * @connector: reference to the central DRM connector control structure
+ */
+static int ws2401_get_modes(struct drm_panel *panel,
+ struct drm_connector *connector)
+{
+ struct ws2401 *ws = to_ws2401(panel);
+ struct drm_display_mode *mode;
+ static const u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+
+ /*
+ * We just support the LMS380KF01 so far, if we implement more panels
+ * this mode, the following connector display_info settings and
+ * probably the custom DCS sequences needs to selected based on what
+ * the target panel needs.
+ */
+ mode = drm_mode_duplicate(connector->dev, &lms380kf01_480_800_mode);
+ if (!mode) {
+ dev_err(ws->dev, "failed to add mode\n");
+ return -ENOMEM;
+ }
+
+ connector->display_info.bpc = 8;
+ connector->display_info.width_mm = mode->width_mm;
+ connector->display_info.height_mm = mode->height_mm;
+ connector->display_info.bus_flags =
+ DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE;
+ drm_display_info_set_bus_formats(&connector->display_info,
+ &bus_format, 1);
+
+ 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 ws2401_drm_funcs = {
+ .disable = ws2401_disable,
+ .unprepare = ws2401_unprepare,
+ .prepare = ws2401_prepare,
+ .enable = ws2401_enable,
+ .get_modes = ws2401_get_modes,
+};
+
+static int ws2401_set_brightness(struct backlight_device *bl)
+{
+ struct ws2401 *ws = bl_get_data(bl);
+ struct mipi_dbi *dbi = &ws->dbi;
+ u8 brightness = backlight_get_brightness(bl);
+
+ if (backlight_is_blank(bl)) {
+ mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x00);
+ } else {
+ mipi_dbi_command(dbi, WS2401_WRCTRLD, 0x2c);
+ mipi_dbi_command(dbi, WS2401_WRDISBV, brightness);
+ }
+
+ return 0;
+}
+
+static const struct backlight_ops ws2401_bl_ops = {
+ .update_status = ws2401_set_brightness,
+};
+
+static const struct backlight_properties ws2401_bl_props = {
+ .type = BACKLIGHT_PLATFORM,
+ .brightness = 120,
+ .max_brightness = U8_MAX,
+};
+
+static int ws2401_probe(struct spi_device *spi)
+{
+ struct device *dev = &spi->dev;
+ struct ws2401 *ws;
+ int ret;
+
+ ws = devm_kzalloc(dev, sizeof(*ws), GFP_KERNEL);
+ if (!ws)
+ return -ENOMEM;
+ ws->dev = dev;
+
+ /*
+ * VCI is the analog voltage supply
+ * VCCIO is the digital I/O voltage supply
+ */
+ ws->regulators[0].supply = "vci";
+ ws->regulators[1].supply = "vccio";
+ ret = devm_regulator_bulk_get(dev,
+ ARRAY_SIZE(ws->regulators),
+ ws->regulators);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to get regulators\n");
+
+ ws->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(ws->reset)) {
+ ret = PTR_ERR(ws->reset);
+ return dev_err_probe(dev, ret, "no RESET GPIO\n");
+ }
+
+ ret = mipi_dbi_spi_init(spi, &ws->dbi, NULL);
+ if (ret)
+ return dev_err_probe(dev, ret, "MIPI DBI init failed\n");
+ ws->dbi.read_commands = ws2401_dbi_read_commands;
+
+ ws2401_power_on(ws);
+ ws2401_read_mtp_id(ws);
+ ws2401_power_off(ws);
+
+ drm_panel_init(&ws->panel, dev, &ws2401_drm_funcs,
+ DRM_MODE_CONNECTOR_DPI);
+
+ ret = drm_panel_of_backlight(&ws->panel);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "failed to get external backlight device\n");
+
+ if (!ws->panel.backlight) {
+ dev_dbg(dev, "no external backlight, using internal backlight\n");
+ ws->panel.backlight =
+ devm_backlight_device_register(dev, "ws2401", dev, ws,
+ &ws2401_bl_ops, &ws2401_bl_props);
+ if (IS_ERR(ws->panel.backlight))
+ return dev_err_probe(dev, PTR_ERR(ws->panel.backlight),
+ "failed to register backlight device\n");
+ } else {
+ dev_dbg(dev, "using external backlight\n");
+ }
+
+ spi_set_drvdata(spi, ws);
+
+ drm_panel_add(&ws->panel);
+ dev_dbg(dev, "added panel\n");
+
+ return 0;
+}
+
+static int ws2401_remove(struct spi_device *spi)
+{
+ struct ws2401 *ws = spi_get_drvdata(spi);
+
+ drm_panel_remove(&ws->panel);
+ return 0;
+}
+
+/*
+ * Samsung LMS380KF01 is the one instance of this display controller that we
+ * know about, but if more are found, the controller can be parameterized
+ * here and used for other configurations.
+ */
+static const struct of_device_id ws2401_match[] = {
+ { .compatible = "samsung,lms380kf01", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ws2401_match);
+
+static struct spi_driver ws2401_driver = {
+ .probe = ws2401_probe,
+ .remove = ws2401_remove,
+ .driver = {
+ .name = "ws2401-panel",
+ .of_match_table = ws2401_match,
+ },
+};
+module_spi_driver(ws2401_driver);
+
+MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
+MODULE_DESCRIPTION("Samsung WS2401 panel driver");
+MODULE_LICENSE("GPL v2");
projects / platform / kernel / linux-rpi.git / commitdiff