[PATCH v2 4/9] drm/panel: Add driver for the LG Philips LB035Q02 panel

Laurent Pinchart
2019-08-10T23:11:01Z

This panel is used on the Gumstix Overo Palo35.

The code is based on the omapdrm-specific panel-lgphilips-lb035q02
driver.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
---
Changes since v1:

- Comments updates
- Store width_mm and height_mm in drm_display_mode
- Use drm_panel_disable() in .remove() handler
---
drivers/gpu/drm/panel/Kconfig | 8 +
drivers/gpu/drm/panel/Makefile | 1 +
drivers/gpu/drm/panel/panel-lg-lb035q02.c | 237 ++++++++++++++++++++++
3 files changed, 246 insertions(+)
create mode 100644 drivers/gpu/drm/panel/panel-lg-lb035q02.c

diff --git a/drivers/gpu/drm/panel/Kconfig b/drivers/gpu/drm/panel/Kconfig
index eaecd40cc32e..87cdc330672b 100644
--- a/drivers/gpu/drm/panel/Kconfig
+++ b/drivers/gpu/drm/panel/Kconfig
@@ -103,6 +103,14 @@ config DRM_PANEL_SAMSUNG_LD9040
depends on OF && SPI
select VIDEOMODE_HELPERS

+config DRM_PANEL_LG_LB035Q02
+ tristate "LG LB035Q024573 RGB panel"
+ depends on GPIOLIB && OF && SPI
+ help
+ Say Y here if you want to enable support for the LB035Q02 RGB panel
+ (found on the Gumstix Overo Palo35 board). To compile this driver as
+ a module, choose M here.
+
config DRM_PANEL_LG_LG4573
tristate "LG4573 RGB/SPI panel"
depends on OF && SPI
diff --git a/drivers/gpu/drm/panel/Makefile b/drivers/gpu/drm/panel/Makefile
index 62dae45f8f74..9bc6f3c5bf96 100644
--- a/drivers/gpu/drm/panel/Makefile
+++ b/drivers/gpu/drm/panel/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_DRM_PANEL_ILITEK_ILI9881C) += panel-ilitek-ili9881c.o
obj-$(CONFIG_DRM_PANEL_INNOLUX_P079ZCA) += panel-innolux-p079zca.o
obj-$(CONFIG_DRM_PANEL_JDI_LT070ME05000) += panel-jdi-lt070me05000.o
obj-$(CONFIG_DRM_PANEL_KINGDISPLAY_KD097D04) += panel-kingdisplay-kd097d04.o
+obj-$(CONFIG_DRM_PANEL_LG_LB035Q02) += panel-lg-lb035q02.o
obj-$(CONFIG_DRM_PANEL_LG_LG4573) += panel-lg-lg4573.o
obj-$(CONFIG_DRM_PANEL_NOVATEK_NT39016) += panel-novatek-nt39016.o
obj-$(CONFIG_DRM_PANEL_OLIMEX_LCD_OLINUXINO) += panel-olimex-lcd-olinuxino.o
diff --git a/drivers/gpu/drm/panel/panel-lg-lb035q02.c b/drivers/gpu/drm/panel/panel-lg-lb035q02.c
new file mode 100644
index 000000000000..694489fb91b2
--- /dev/null
+++ b/drivers/gpu/drm/panel/panel-lg-lb035q02.c
@@ -0,0 +1,237 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * LG.Philips LB035Q02 LCD Panel Driver
+ *
+ * Copyright (C) 2019 Texas Instruments Incorporated
+ *
+ * Based on the omapdrm-specific panel-lgphilips-lb035q02 driver
+ *
+ * Copyright (C) 2013 Texas Instruments Incorporated
+ * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>
+ *
+ * Based on a driver by: Steve Sakoman <steve@sakoman.com>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+
+#include <drm/drm_connector.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_panel.h>
+
+struct lb035q02_device {
+ struct drm_panel panel;
+
+ struct spi_device *spi;
+ struct gpio_desc *enable_gpio;
+};
+
+#define to_lb035q02_device(p) container_of(p, struct lb035q02_device, panel)
+
+static int lb035q02_write(struct lb035q02_device *lcd, u16 reg, u16 val)
+{
+ struct spi_message msg;
+ struct spi_transfer index_xfer = {
+ .len = 3,
+ .cs_change = 1,
+ };
+ struct spi_transfer value_xfer = {
+ .len = 3,
+ };
+ u8 buffer[16];
+
+ spi_message_init(&msg);
+
+ /* register index */
+ buffer[0] = 0x70;
+ buffer[1] = 0x00;
+ buffer[2] = reg & 0x7f;
+ index_xfer.tx_buf = buffer;
+ spi_message_add_tail(&index_xfer, &msg);
+
+ /* register value */
+ buffer[4] = 0x72;
+ buffer[5] = val >> 8;
+ buffer[6] = val;
+ value_xfer.tx_buf = buffer + 4;
+ spi_message_add_tail(&value_xfer, &msg);
+
+ return spi_sync(lcd->spi, &msg);
+}
+
+static int lb035q02_init(struct lb035q02_device *lcd)
+{
+ /* Init sequence from page 28 of the lb035q02 spec. */
+ static const struct {
+ u16 index;
+ u16 value;
+ } init_data[] = {
+ { 0x01, 0x6300 },
+ { 0x02, 0x0200 },
+ { 0x03, 0x0177 },
+ { 0x04, 0x04c7 },
+ { 0x05, 0xffc0 },
+ { 0x06, 0xe806 },
+ { 0x0a, 0x4008 },
+ { 0x0b, 0x0000 },
+ { 0x0d, 0x0030 },
+ { 0x0e, 0x2800 },
+ { 0x0f, 0x0000 },
+ { 0x16, 0x9f80 },
+ { 0x17, 0x0a0f },
+ { 0x1e, 0x00c1 },
+ { 0x30, 0x0300 },
+ { 0x31, 0x0007 },
+ { 0x32, 0x0000 },
+ { 0x33, 0x0000 },
+ { 0x34, 0x0707 },
+ { 0x35, 0x0004 },
+ { 0x36, 0x0302 },
+ { 0x37, 0x0202 },
+ { 0x3a, 0x0a0d },
+ { 0x3b, 0x0806 },
+ };
+
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < ARRAY_SIZE(init_data); ++i) {
+ ret = lb035q02_write(lcd, init_data[i].index,
+ init_data[i].value);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int lb035q02_disable(struct drm_panel *panel)
+{
+ struct lb035q02_device *lcd = to_lb035q02_device(panel);
+
+ gpiod_set_value_cansleep(lcd->enable_gpio, 0);
+
+ return 0;
+}
+
+static int lb035q02_enable(struct drm_panel *panel)
+{
+ struct lb035q02_device *lcd = to_lb035q02_device(panel);
+
+ gpiod_set_value_cansleep(lcd->enable_gpio, 1);
+
+ return 0;
+}
+
+static const struct drm_display_mode lb035q02_mode = {
+ .clock = 6500,
+ .hdisplay = 320,
+ .hsync_start = 320 + 20,
+ .hsync_end = 320 + 20 + 2,
+ .htotal = 320 + 20 + 2 + 68,
+ .vdisplay = 240,
+ .vsync_start = 240 + 4,
+ .vsync_end = 240 + 4 + 2,
+ .vtotal = 240 + 4 + 2 + 18,
+ .vrefresh = 60,
+ .type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
+ .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+ .width_mm = 70,
+ .height_mm = 53,
+};
+
+static int lb035q02_get_modes(struct drm_panel *panel)
+{
+ struct drm_connector *connector = panel->connector;
+ struct drm_display_mode *mode;
+
+ mode = drm_mode_duplicate(panel->drm, &lb035q02_mode);
+ if (!mode)
+ return -ENOMEM;
+
+ drm_mode_set_name(mode);
+ drm_mode_probed_add(connector, mode);
+
+ connector->display_info.width_mm = lb035q02_mode.width_mm;
+ connector->display_info.height_mm = lb035q02_mode.height_mm;
+ /*
+ * FIXME: According to the datasheet pixel data is sampled on the
+ * rising edge of the clock, but the code running on the Gumstix Overo
+ * Palo35 indicates sampling on the negative edge. This should be
+ * tested on a real device.
+ */
+ connector->display_info.bus_flags = DRM_BUS_FLAG_DE_HIGH
+ | DRM_BUS_FLAG_SYNC_SAMPLE_POSEDGE
+ | DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE;
+
+ return 1;
+}
+
+static const struct drm_panel_funcs lb035q02_funcs = {
+ .disable = lb035q02_disable,
+ .enable = lb035q02_enable,
+ .get_modes = lb035q02_get_modes,
+};
+
+static int lb035q02_probe(struct spi_device *spi)
+{
+ struct lb035q02_device *lcd;
+ int ret;
+
+ lcd = devm_kzalloc(&spi->dev, sizeof(*lcd), GFP_KERNEL);
+ if (lcd == NULL)
+ return -ENOMEM;
+
+ spi_set_drvdata(spi, lcd);
+ lcd->spi = spi;
+
+ lcd->enable_gpio = devm_gpiod_get(&spi->dev, "enable", GPIOD_OUT_LOW);
+ if (IS_ERR(lcd->enable_gpio)) {
+ dev_err(&spi->dev, "failed to parse enable gpio\n");
+ return PTR_ERR(lcd->enable_gpio);
+ }
+
+ ret = lb035q02_init(lcd);
+ if (ret < 0)
+ return ret;
+
+ drm_panel_init(&lcd->panel);
+ lcd->panel.dev = &lcd->spi->dev;
+ lcd->panel.funcs = &lb035q02_funcs;
+
+ return drm_panel_add(&lcd->panel);
+}
+
+static int lb035q02_remove(struct spi_device *spi)
+{
+ struct lb035q02_device *lcd = spi_get_drvdata(spi);
+
+ drm_panel_remove(&lcd->panel);
+ drm_panel_disable(&lcd->panel);
+
+ return 0;
+}
+
+static const struct of_device_id lb035q02_of_match[] = {
+ { .compatible = "lgphilips,lb035q02", },
+ { /* sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, lb035q02_of_match);
+
+static struct spi_driver lb035q02_driver = {
+ .probe = lb035q02_probe,
+ .remove = lb035q02_remove,
+ .driver = {
+ .name = "panel-lg-lb035q02",
+ .of_match_table = lb035q02_of_match,
+ },
+};
+
+module_spi_driver(lb035q02_driver);
+
+MODULE_ALIAS("spi:lgphilips,lb035q02");
+MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
+MODULE_DESCRIPTION("LG.Philips LB035Q02 LCD Panel driver");
+MODULE_LICENSE("GPL");