drm/panel: Add support for LG LG4573 480x800 4.3" panel

The LG4573 is used on the LG LCD LB043WV2-SD01, an industrial 4.3" TFT
panel with SPI control interface.

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Thierry Reding <treding@nvidia.com>

4 files changed, 326 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/panel/lg,lg4573.txt b/Documentation/devicetree/bindings/panel/lg,lg4573.txt
new file mode 100644
index 000000000000..824441f4e95a
--- /dev/null
+++ b/Documentation/devicetree/bindings/panel/lg,lg4573.txt
@@ -0,0 +1,19 @@
+LG LG4573 TFT Liquid Crystal Display with SPI control bus
+
+Required properties:
+  - compatible: "lg,lg4573"
+  - reg: address of the panel on the SPI bus
+
+The panel must obey rules for SPI slave device specified in document [1].
+
+[1]: Documentation/devicetree/bindings/spi/spi-bus.txt
+
+Example:
+
+        lcd_panel: display@0 {
+                #address-cells = <1>;
+                #size-cells = <1>;
+                compatible = "lg,lg4573";
+                spi-max-frequency = <10000000>;
+                reg = <0>;
+        };
diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index 5be25d9282e3..7d4704b1292b 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -23,6 +23,14 @@ config DRM_PANEL_SAMSUNG_LD9040
         depends on OF && SPI
         select VIDEOMODE_HELPERS
 
+config DRM_PANEL_LG_LG4573
+        tristate "LG4573 RGB/SPI panel"
+        depends on OF && SPI
+        select VIDEOMODE_HELPERS
+        help
+          Say Y here if you want to enable support for LG4573 RGB panel.
+          To compile this driver as a module, choose M here.
+
 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 8026ce5d18b5..d0f016dd7ddb 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -1,4 +1,5 @@
 obj-$(CONFIG_DRM_PANEL_SIMPLE) += panel-simple.o
+obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o
 obj-$(CONFIG_DRM_PANEL_SAMSUNG_LD9040) += panel-samsung-ld9040.o
 obj-$(CONFIG_DRM_PANEL_SAMSUNG_S6E8AA0) += panel-samsung-s6e8aa0.o
 obj-$(CONFIG_DRM_PANEL_SHARP_LQ101R1SX01) += panel-sharp-lq101r1sx01.o
diff --git a/drivers/gpu/drm/panel/panel-lg-lg4573.c b/drivers/gpu/drm/panel/panel-lg-lg4573.c
new file mode 100644
index 000000000000..a7b4939cee6d
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-lg-lg4573.c
@@ -0,0 +1,298 @@
+/*
+ * Copyright (C) 2015 Heiko Schocher <hs@denx.de>
+ *
+ * from:
+ * drivers/gpu/drm/panel/panel-ld9040.c
+ * ld9040 AMOLED LCD drm_panel driver.
+ *
+ * Copyright (c) 2014 Samsung Electronics Co., Ltd
+ * Derived from drivers/video/backlight/ld9040.c
+ *
+ * Andrzej Hajda <a.hajda@samsung.com>
+ *
+ * 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>
+
+struct lg4573 {
+        struct drm_panel panel;
+        struct spi_device *spi;
+        struct videomode vm;
+};
+
+static inline struct lg4573 *panel_to_lg4573(struct drm_panel *panel)
+{
+        return container_of(panel, struct lg4573, panel);
+}
+
+static int lg4573_spi_write_u16(struct lg4573 *ctx, u16 data)
+{
+        struct spi_transfer xfer = {
+                .len = 2,
+        };
+        u16 temp = cpu_to_be16(data);
+        struct spi_message msg;
+
+        dev_dbg(ctx->panel.dev, "writing data: %x\n", data);
+        xfer.tx_buf = &temp;
+        spi_message_init(&msg);
+        spi_message_add_tail(&xfer, &msg);
+
+        return spi_sync(ctx->spi, &msg);
+}
+
+static int lg4573_spi_write_u16_array(struct lg4573 *ctx, const u16 *buffer,
+                                      unsigned int count)
+{
+        unsigned int i;
+        int ret;
+
+        for (i = 0; i < count; i++) {
+                ret = lg4573_spi_write_u16(ctx, buffer[i]);
+                if (ret)
+                        return ret;
+        }
+
+        return 0;
+}
+
+static int lg4573_spi_write_dcs(struct lg4573 *ctx, u8 dcs)
+{
+        return lg4573_spi_write_u16(ctx, (0x70 << 8 | dcs));
+}
+
+static int lg4573_display_on(struct lg4573 *ctx)
+{
+        int ret;
+
+        ret = lg4573_spi_write_dcs(ctx, MIPI_DCS_EXIT_SLEEP_MODE);
+        if (ret)
+                return ret;
+
+        msleep(5);
+
+        return lg4573_spi_write_dcs(ctx, MIPI_DCS_SET_DISPLAY_ON);
+}
+
+static int lg4573_display_off(struct lg4573 *ctx)
+{
+        int ret;
+
+        ret = lg4573_spi_write_dcs(ctx, MIPI_DCS_SET_DISPLAY_OFF);
+        if (ret)
+                return ret;
+
+        msleep(120);
+
+        return lg4573_spi_write_dcs(ctx, MIPI_DCS_ENTER_SLEEP_MODE);
+}
+
+static int lg4573_display_mode_settings(struct lg4573 *ctx)
+{
+        static const u16 display_mode_settings[] = {
+                0x703A, 0x7270, 0x70B1, 0x7208,
+                0x723B, 0x720F, 0x70B2, 0x7200,
+                0x72C8, 0x70B3, 0x7200, 0x70B4,
+                0x7200, 0x70B5, 0x7242, 0x7210,
+                0x7210, 0x7200, 0x7220, 0x70B6,
+                0x720B, 0x720F, 0x723C, 0x7213,
+                0x7213, 0x72E8, 0x70B7, 0x7246,
+                0x7206, 0x720C, 0x7200, 0x7200,
+        };
+
+        dev_dbg(ctx->panel.dev, "transfer display mode settings\n");
+        return lg4573_spi_write_u16_array(ctx, display_mode_settings,
+                                          ARRAY_SIZE(display_mode_settings));
+}
+
+static int lg4573_power_settings(struct lg4573 *ctx)
+{
+        static const u16 power_settings[] = {
+                0x70C0, 0x7201, 0x7211, 0x70C3,
+                0x7207, 0x7203, 0x7204, 0x7204,
+                0x7204, 0x70C4, 0x7212, 0x7224,
+                0x7218, 0x7218, 0x7202, 0x7249,
+                0x70C5, 0x726F, 0x70C6, 0x7241,
+                0x7263,
+        };
+
+        dev_dbg(ctx->panel.dev, "transfer power settings\n");
+        return lg4573_spi_write_u16_array(ctx, power_settings,
+                                          ARRAY_SIZE(power_settings));
+}
+
+static int lg4573_gamma_settings(struct lg4573 *ctx)
+{
+        static const u16 gamma_settings[] = {
+                0x70D0, 0x7203, 0x7207, 0x7273,
+                0x7235, 0x7200, 0x7201, 0x7220,
+                0x7200, 0x7203, 0x70D1, 0x7203,
+                0x7207, 0x7273, 0x7235, 0x7200,
+                0x7201, 0x7220, 0x7200, 0x7203,
+                0x70D2, 0x7203, 0x7207, 0x7273,
+                0x7235, 0x7200, 0x7201, 0x7220,
+                0x7200, 0x7203, 0x70D3, 0x7203,
+                0x7207, 0x7273, 0x7235, 0x7200,
+                0x7201, 0x7220, 0x7200, 0x7203,
+                0x70D4, 0x7203, 0x7207, 0x7273,
+                0x7235, 0x7200, 0x7201, 0x7220,
+                0x7200, 0x7203, 0x70D5, 0x7203,
+                0x7207, 0x7273, 0x7235, 0x7200,
+                0x7201, 0x7220, 0x7200, 0x7203,
+        };
+
+        dev_dbg(ctx->panel.dev, "transfer gamma settings\n");
+        return lg4573_spi_write_u16_array(ctx, gamma_settings,
+                                          ARRAY_SIZE(gamma_settings));
+}
+
+static int lg4573_init(struct lg4573 *ctx)
+{
+        int ret;
+
+        dev_dbg(ctx->panel.dev, "initializing LCD\n");
+
+        ret = lg4573_display_mode_settings(ctx);
+        if (ret)
+                return ret;
+
+        ret = lg4573_power_settings(ctx);
+        if (ret)
+                return ret;
+
+        return lg4573_gamma_settings(ctx);
+}
+
+static int lg4573_power_on(struct lg4573 *ctx)
+{
+        return lg4573_display_on(ctx);
+}
+
+static int lg4573_disable(struct drm_panel *panel)
+{
+        struct lg4573 *ctx = panel_to_lg4573(panel);
+
+        return lg4573_display_off(ctx);
+}
+
+static int lg4573_enable(struct drm_panel *panel)
+{
+        struct lg4573 *ctx = panel_to_lg4573(panel);
+
+        lg4573_init(ctx);
+
+        return lg4573_power_on(ctx);
+}
+
+static const struct drm_display_mode default_mode = {
+        .clock = 27000,
+        .hdisplay = 480,
+        .hsync_start = 480 + 10,
+        .hsync_end = 480 + 10 + 59,
+        .htotal = 480 + 10 + 59 + 10,
+        .vdisplay = 800,
+        .vsync_start = 800 + 15,
+        .vsync_end = 800 + 15 + 15,
+        .vtotal = 800 + 15 + 15 + 15,
+        .vrefresh = 60,
+};
+
+static int lg4573_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) {
+                dev_err(panel->drm->dev, "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);
+
+        panel->connector->display_info.width_mm = 61;
+        panel->connector->display_info.height_mm = 103;
+
+        return 1;
+}
+
+static const struct drm_panel_funcs lg4573_drm_funcs = {
+        .disable = lg4573_disable,
+        .enable = lg4573_enable,
+        .get_modes = lg4573_get_modes,
+};
+
+static int lg4573_probe(struct spi_device *spi)
+{
+        struct lg4573 *ctx;
+        int ret;
+
+        ctx = devm_kzalloc(&spi->dev, sizeof(*ctx), GFP_KERNEL);
+        if (!ctx)
+                return -ENOMEM;
+
+        ctx->spi = spi;
+
+        spi_set_drvdata(spi, ctx);
+        spi->bits_per_word = 8;
+
+        ret = spi_setup(spi);
+        if (ret < 0) {
+                dev_err(&spi->dev, "SPI setup failed: %d\n", ret);
+                return ret;
+        }
+
+        drm_panel_init(&ctx->panel);
+        ctx->panel.dev = &spi->dev;
+        ctx->panel.funcs = &lg4573_drm_funcs;
+
+        return drm_panel_add(&ctx->panel);
+}
+
+static int lg4573_remove(struct spi_device *spi)
+{
+        struct lg4573 *ctx = spi_get_drvdata(spi);
+
+        lg4573_display_off(ctx);
+        drm_panel_remove(&ctx->panel);
+
+        return 0;
+}
+
+static const struct of_device_id lg4573_of_match[] = {
+        { .compatible = "lg,lg4573" },
+        { }
+};
+MODULE_DEVICE_TABLE(of, lg4573_of_match);
+
+static struct spi_driver lg4573_driver = {
+        .probe = lg4573_probe,
+        .remove = lg4573_remove,
+        .driver = {
+                .name = "lg4573",
+                .owner = THIS_MODULE,
+                .of_match_table = lg4573_of_match,
+        },
+};
+module_spi_driver(lg4573_driver);
+
+MODULE_AUTHOR("Heiko Schocher <hs@denx.de>");
+MODULE_DESCRIPTION("lg4573 LCD Driver");
+MODULE_LICENSE("GPL v2");