drivers: video: Add Support for Himax HX8238D Panel

* SPI based initialization for HX8238D
* Resolution: 320x240
* Color-Mode: RGB

* Initial Work is done by Sjoerd Simons
  https://gitlab.apertis.org/packaging/u-boot/-/blob\
  /5f259720e3e64965d50da89a841ad6eb256a47df/debian/patches\
  /apertis/powertools/0005-video-Add-Himax-HX8238-D-driver.patch

* Tested on Bosch Guardian Board

Cc: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Signed-off-by: Moses Christopher <BollavarapuMoses.Christopher@in.bosch.com>

3 files changed, 208 insertions, 0 deletions

diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index bdacf67795..667157c2e9 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -160,6 +160,16 @@ config CONSOLE_TRUETYPE
 	  With this option you can adjust the text size and use a variety of
 	  fonts. Note that this is noticeably slower than with normal console.
 
+config DM_PANEL_HX8238D
+	bool "Enable Himax HX-8238D LCD driver"
+	depends on DM_VIDEO
+	help
+	  Support for HX-8238D LCD Panel
+	  The  HX8238-D is a single chip controller and driver LSI that
+	  integrates the power circuit.
+	  It can drive a maximum 960x240 dot graphics on a-TFT panel
+	  displays in 16M colors with dithering.
+
 config CONSOLE_TRUETYPE_SIZE
 	int "TrueType font size"
 	depends on CONSOLE_TRUETYPE
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index 832475c9a5..933f06e9d8 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_VIDEO_MIPI_DSI) += dsi-host-uclass.o
 obj-$(CONFIG_DM_VIDEO) += video-uclass.o vidconsole-uclass.o
 obj-$(CONFIG_DM_VIDEO) += video_bmp.o
 obj-$(CONFIG_PANEL) += panel-uclass.o
+obj-$(CONFIG_PANEL_HX8238D) += hx8238d.o
 obj-$(CONFIG_SIMPLE_PANEL) += simple_panel.o
 endif
 
diff --git a/drivers/video/hx8238d.c b/drivers/video/hx8238d.c
new file mode 100644
index 0000000000..f7e7753a53
--- /dev/null
+++ b/drivers/video/hx8238d.c
@@ -0,0 +1,197 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copied from simple-panel
+ * Copyright (c) 2016 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ * Copyright (c) 2018 Sjoerd Simons <sjoerd.simons@collabora.co.uk>
+ * Modified by Moses Christopher <BollavarapuMoses.Christopher@in.bosch.com>
+ *
+ * Panel Initialization for HX8238D panel from Himax
+ * Resolution: 320x240
+ * Color-Mode: RGB
+ *
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <panel.h>
+#include <spi.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Register Address */
+#define HX8238D_OUTPUT_CTRL_ADDR        0x01
+#define HX8238D_LCD_AC_CTRL_ADDR        0x02
+#define HX8238D_POWER_CTRL_1_ADDR       0x03
+#define HX8238D_DATA_CLR_CTRL_ADDR      0X04
+#define HX8238D_FUNCTION_CTRL_ADDR      0x05
+#define HX8238D_LED_CTRL_ADDR           0x08
+#define HX8238D_CONT_BRIGHT_CTRL_ADDR   0x0A
+#define HX8238D_FRAME_CYCLE_CTRL_ADDR   0x0B
+#define HX8238D_POWER_CTRL_2_ADDR       0x0D
+#define HX8238D_POWER_CTRL_3_ADDR       0x0E
+#define HX8238D_GATE_SCAN_POS_ADDR      0x0F
+#define HX8238D_HORIZONTAL_PORCH_ADDR   0x16
+#define HX8238D_VERTICAL_PORCH_ADDR     0x17
+#define HX8238D_POWER_CTRL_4_ADDR       0x1E
+#define HX8238D_GAMMA_CTRL_1_ADDR       0x30
+#define HX8238D_GAMMA_CTRL_2_ADDR       0x31
+#define HX8238D_GAMMA_CTRL_3_ADDR       0x32
+#define HX8238D_GAMMA_CTRL_4_ADDR       0x33
+#define HX8238D_GAMMA_CTRL_5_ADDR       0x34
+#define HX8238D_GAMMA_CTRL_6_ADDR       0x35
+#define HX8238D_GAMMA_CTRL_7_ADDR       0x36
+#define HX8238D_GAMMA_CTRL_8_ADDR       0x37
+#define HX8238D_GAMMA_CTRL_9_ADDR       0x3A
+#define HX8238D_GAMMA_CTRL_10_ADDR      0x3B
+
+/* Register Data */
+#define HX8238D_OUTPUT_CTRL             0x6300
+#define HX8238D_LCD_AC_CTRL             0x0200
+#define HX8238D_POWER_CTRL_1            0x6564
+#define HX8238D_DATA_CLR_CTRL           0x04C7
+#define HX8238D_FUNCTION_CTRL           0xA884
+#define HX8238D_LED_CTRL                0x00CE
+#define HX8238D_CONT_BRIGHT_CTRL        0x4008
+#define HX8238D_FRAME_CYCLE_CTRL        0xD400
+#define HX8238D_POWER_CTRL_2            0x3229
+#define HX8238D_POWER_CTRL_3            0x1200
+#define HX8238D_GATE_SCAN_POS           0x0000
+#define HX8238D_HORIZONTAL_PORCH        0x9F80
+#define HX8238D_VERTICAL_PORCH          0x3F02
+#define HX8238D_POWER_CTRL_4            0x005C
+
+/* Gamma Control */
+#define HX8238D_GAMMA_CTRL_1            0x0103
+#define HX8238D_GAMMA_CTRL_2            0x0407
+#define HX8238D_GAMMA_CTRL_3            0x0705
+#define HX8238D_GAMMA_CTRL_4            0x0002
+#define HX8238D_GAMMA_CTRL_5            0x0505
+#define HX8238D_GAMMA_CTRL_6            0x0303
+#define HX8238D_GAMMA_CTRL_7            0x0707
+#define HX8238D_GAMMA_CTRL_8            0x0100
+#define HX8238D_GAMMA_CTRL_9            0x1F00
+#define HX8238D_GAMMA_CTRL_10           0x000F
+
+/* Primary SPI register identification, 011100 */
+/* Select register, RS=0, RS=0 */
+/* Write  register, RS=1, RW=0 */
+#define HX8238D_PRIMARY_SELECT_REG 0x70
+#define HX8238D_PRIMARY_WRITE_REG  (HX8238D_PRIMARY_SELECT_REG | (0x1 << 1))
+
+#define HX8238D_REG_BIT_LEN        24
+
+struct hx8238d_priv {
+	struct spi_slave *spi;
+};
+
+static int hx8238d_ofdata_to_platdata(struct udevice *dev)
+{
+	struct hx8238d_priv *priv = dev_get_priv(dev);
+
+	priv->spi = dev_get_parent_priv(dev);
+
+	return 0;
+}
+
+/* data[0] => REGISTER ADDRESS */
+/* data[1] => REGISTER VALUE   */
+struct hx8238d_command {
+	u16 data[2];
+};
+
+static struct hx8238d_command hx8238d_init_commands[] = {
+	{ .data = { HX8238D_OUTPUT_CTRL_ADDR,      HX8238D_OUTPUT_CTRL } },
+	{ .data = { HX8238D_LCD_AC_CTRL_ADDR,      HX8238D_LCD_AC_CTRL } },
+	{ .data = { HX8238D_POWER_CTRL_1_ADDR,     HX8238D_POWER_CTRL_1 } },
+	{ .data = { HX8238D_DATA_CLR_CTRL_ADDR,    HX8238D_DATA_CLR_CTRL } },
+	{ .data = { HX8238D_FUNCTION_CTRL_ADDR,    HX8238D_FUNCTION_CTRL } },
+	{ .data = { HX8238D_LED_CTRL_ADDR,         HX8238D_LED_CTRL } },
+	{ .data = { HX8238D_CONT_BRIGHT_CTRL_ADDR, HX8238D_CONT_BRIGHT_CTRL } },
+	{ .data = { HX8238D_FRAME_CYCLE_CTRL_ADDR, HX8238D_FRAME_CYCLE_CTRL } },
+	{ .data = { HX8238D_POWER_CTRL_2_ADDR,     HX8238D_POWER_CTRL_2 } },
+	{ .data = { HX8238D_POWER_CTRL_3_ADDR,     HX8238D_POWER_CTRL_3 } },
+	{ .data = { HX8238D_GATE_SCAN_POS_ADDR,    HX8238D_GATE_SCAN_POS } },
+	{ .data = { HX8238D_HORIZONTAL_PORCH_ADDR, HX8238D_HORIZONTAL_PORCH } },
+	{ .data = { HX8238D_VERTICAL_PORCH_ADDR,   HX8238D_VERTICAL_PORCH } },
+	{ .data = { HX8238D_POWER_CTRL_4_ADDR,     HX8238D_POWER_CTRL_4 } },
+	{ .data = { HX8238D_GAMMA_CTRL_1_ADDR,     HX8238D_GAMMA_CTRL_1 } },
+	{ .data = { HX8238D_GAMMA_CTRL_2_ADDR,     HX8238D_GAMMA_CTRL_2 } },
+	{ .data = { HX8238D_GAMMA_CTRL_3_ADDR,     HX8238D_GAMMA_CTRL_3 } },
+	{ .data = { HX8238D_GAMMA_CTRL_4_ADDR,     HX8238D_GAMMA_CTRL_4 } },
+	{ .data = { HX8238D_GAMMA_CTRL_5_ADDR,     HX8238D_GAMMA_CTRL_5 } },
+	{ .data = { HX8238D_GAMMA_CTRL_6_ADDR,     HX8238D_GAMMA_CTRL_6 } },
+	{ .data = { HX8238D_GAMMA_CTRL_7_ADDR,     HX8238D_GAMMA_CTRL_7 } },
+	{ .data = { HX8238D_GAMMA_CTRL_8_ADDR,     HX8238D_GAMMA_CTRL_8 } },
+	{ .data = { HX8238D_GAMMA_CTRL_9_ADDR,     HX8238D_GAMMA_CTRL_9 } },
+	{ .data = { HX8238D_GAMMA_CTRL_10_ADDR,    HX8238D_GAMMA_CTRL_10 } },
+};
+
+/*
+ * Generate Primary Register Buffer for Register Select and Register Write
+ * First 6 MSB bits of Primary Register is represented with 011100
+ *
+ */
+static void hx8238d_generate_reg_buffers(struct hx8238d_command command,
+					 u8 *sr_buf, uint8_t *wr_buf)
+{
+	struct hx8238d_command cmd = command;
+
+	sr_buf[0] = HX8238D_PRIMARY_SELECT_REG;
+	sr_buf[1] = (cmd.data[0] >> 8) & 0xff;
+	sr_buf[2] = (cmd.data[0]) & 0xff;
+
+	wr_buf[0] = HX8238D_PRIMARY_WRITE_REG;
+	wr_buf[1] = (cmd.data[1] >> 8) & 0xff;
+	wr_buf[2] = (cmd.data[1]) & 0xff;
+}
+
+static int hx8238d_probe(struct udevice *dev)
+{
+	struct hx8238d_priv *priv = dev_get_priv(dev);
+	int ret;
+
+	ret = spi_claim_bus(priv->spi);
+	if (ret) {
+		debug("Failed to claim bus: %d\n", ret);
+		return ret;
+	}
+
+	for (int i = 0; i < ARRAY_SIZE(hx8238d_init_commands); i++) {
+		u8 sr_buf[3], wr_buf[3];
+		const struct hx8238d_command cmd = hx8238d_init_commands[i];
+
+		hx8238d_generate_reg_buffers(cmd, sr_buf, wr_buf);
+		ret = spi_xfer(priv->spi, HX8238D_REG_BIT_LEN, sr_buf, NULL,
+			       SPI_XFER_BEGIN | SPI_XFER_END);
+		if (ret) {
+			debug("Failed to select register %d\n", ret);
+			goto free;
+		}
+
+		ret = spi_xfer(priv->spi, HX8238D_REG_BIT_LEN, wr_buf, NULL,
+			       SPI_XFER_BEGIN | SPI_XFER_END);
+		if (ret) {
+			debug("Failed to write value %d\n", ret);
+			goto free;
+		}
+	}
+
+free:
+	spi_release_bus(priv->spi);
+	return ret;
+}
+
+static const struct udevice_id hx8238d_ids[] = {
+	{ .compatible = "himax,hx8238d" },
+	{ }
+};
+
+U_BOOT_DRIVER(hx8238d) = {
+	.name = "hx8238d",
+	.id = UCLASS_PANEL,
+	.of_match = hx8238d_ids,
+	.ofdata_to_platdata = hx8238d_ofdata_to_platdata,
+	.probe = hx8238d_probe,
+	.priv_auto_alloc_size = sizeof(struct hx8238d_priv),
+};