gpboot: Add rudimentary ST7585 LCD driver

Add a basic, bit-banged ST7585 LCD driver, useful for showing a boot logo on the Hero4's front panel display. Signed-off-by: evilwombat <evilwombat@server.fake>
evilwombat · Dec 30, 2015 · f967021 · f967021
1 parent f1ab838
commit f967021
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diff --git a/gp_lcd.c b/gp_lcd.c
@@ -0,0 +1,178 @@
+#include <libusb.h>
+#include "gp_api.h"
+
+#define GPIO_BIT(a)	(1 << (a & 0x1f))
+
+#define GPIO_AFSEL_OFFSET	0x18
+#define GPIO_DIR_OFFSET		0x04
+#define GPIO_DATA_OFFSET	0x00
+
+static unsigned int hero4_gpio_offsets[] = {
+	0x70009000,
+	0x7000a000,
+	0x7000e000,
+	0x70010000,
+	0x70011000,
+};
+
+struct lcd_hw_info {
+	int spi_clk_gpio;
+	int spi_mosi_gpio;
+	int spi_miso_gpio;
+	int spi_cs_gpio;
+	int enable_gpio;
+	int *gpio_offsets;
+	int last_addr, last_val;
+	int spi_all_cs_gpios[];
+};
+
+static struct lcd_hw_info hero4_lcd_hw_info = {
+	.spi_clk_gpio	= 2,
+	.spi_mosi_gpio	= 3,
+	.spi_miso_gpio	= 4,
+	.spi_cs_gpio	= 6,
+	.enable_gpio	= 31,
+	.gpio_offsets 	= hero4_gpio_offsets,
+	.spi_all_cs_gpios = {5, 6, -1},
+};
+
+static void gpio_write_bit(libusb_device_handle *dev, struct lcd_hw_info *hw_info,
+		    int gpio, int offset, int bit_value)
+{
+	unsigned int addr;
+	unsigned int val;
+
+	addr = hw_info->gpio_offsets[gpio / 32] + offset;
+
+	if (hw_info->last_addr == addr)
+		val = hw_info->last_val;
+	else
+		val = gp_read_reg(dev, addr);
+
+	val &= ~(GPIO_BIT(gpio));
+
+	if (bit_value)
+		val |= GPIO_BIT(gpio);
+
+	gp_write_reg(dev, addr, val);
+
+	hw_info->last_addr = addr;
+	hw_info->last_val = val;
+}
+
+static void st7585_spi_send_word(struct libusb_device_handle *dev, struct lcd_hw_info *hw_info,
+			  unsigned int w)
+{
+	int i;
+
+	gpio_write_bit(dev, hw_info, hw_info->spi_cs_gpio, GPIO_DATA_OFFSET, 0);
+	for (i = 0; i < 9; i++) {
+		gpio_write_bit(dev, hw_info, hw_info->spi_clk_gpio, GPIO_DATA_OFFSET, 0);
+		gpio_write_bit(dev, hw_info, hw_info->spi_mosi_gpio, GPIO_DATA_OFFSET, w & (1 << (8 - i)));
+		gpio_write_bit(dev, hw_info, hw_info->spi_clk_gpio, GPIO_DATA_OFFSET, 1);
+	}
+
+	gpio_write_bit(dev, hw_info, hw_info->spi_cs_gpio, 0, 1);
+}
+
+static int st7585_upload_bitmap(libusb_device_handle *dev, struct lcd_hw_info *hw_info,
+				const unsigned char *buffer)
+{
+	unsigned int row, col;
+
+	for (col = 0; col < 8; col++) {
+		st7585_spi_send_word(dev, hw_info, 0x40 | col);
+		st7585_spi_send_word(dev, hw_info, 0x8d);
+
+		for (row = 0; row < 75; row++)
+			st7585_spi_send_word(dev, hw_info, 0x100 | (buffer[col + row * 8]));
+	}
+
+}
+
+static int st7585_configure_panel(libusb_device_handle *dev, struct lcd_hw_info *hw_info)
+{
+	int i = 0;
+
+	/* MISO as input */
+	gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->spi_miso_gpio, GPIO_DIR_OFFSET, 0);
+
+
+	/* Initialize all chip selects */
+	while (hw_info->spi_all_cs_gpios[i] != -1) {
+		gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->spi_all_cs_gpios[i], GPIO_AFSEL_OFFSET, 0);
+		gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->spi_all_cs_gpios[i], GPIO_DIR_OFFSET, 1);
+		gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->spi_all_cs_gpios[i], GPIO_DATA_OFFSET, 1);
+		i++;
+	}
+
+	gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->spi_clk_gpio, GPIO_AFSEL_OFFSET, 0);
+	gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->spi_clk_gpio, GPIO_DIR_OFFSET, 1);
+
+	gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->spi_mosi_gpio, GPIO_AFSEL_OFFSET, 0);
+	gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->spi_mosi_gpio, GPIO_DIR_OFFSET, 1);
+
+	if (hw_info->enable_gpio >= 0) {
+		gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->enable_gpio, GPIO_AFSEL_OFFSET, 0);
+		gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->enable_gpio, GPIO_DIR_OFFSET, 1);
+		gpio_write_bit(dev, &hero4_lcd_hw_info, hw_info->enable_gpio, GPIO_DATA_OFFSET, 1);
+	}
+
+	/* Initialize panel */
+	st7585_spi_send_word(dev, hw_info, 0x21);
+	st7585_spi_send_word(dev, hw_info, 0x9c);
+	st7585_spi_send_word(dev, hw_info, 0x20);
+	st7585_spi_send_word(dev, hw_info, 0x08);
+}
+
+const unsigned char boot_logo[] = {
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x10,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x38,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x3c,0x00,0x60,0x00,0x00,0x00,
+	0x00,0x00,0x66,0x00,0xf0,0x00,0x00,0x00,0x00,0x00,0x43,0xc1,0xb0,0x00,0x00,0x00,
+	0x00,0x00,0xcf,0xff,0x10,0x00,0x00,0x00,0x00,0x00,0xc4,0x0f,0x30,0x00,0x00,0x00,
+	0x00,0x00,0x40,0x02,0x18,0x00,0x00,0x00,0x00,0x00,0xc0,0x02,0x18,0x00,0x00,0x00,
+	0x00,0x01,0x80,0x00,0x1c,0x00,0x00,0x00,0x00,0x03,0x80,0x00,0x06,0x00,0x00,0x00,
+	0x00,0x03,0x00,0x00,0x06,0x00,0x00,0x00,0x00,0x03,0x80,0x00,0x03,0xc0,0x00,0x00,
+	0x00,0x07,0xc0,0x00,0x00,0xe0,0x00,0x00,0x00,0x04,0x40,0x78,0x00,0x30,0x00,0x00,
+	0x00,0x04,0x00,0x60,0x06,0x38,0x00,0x00,0x00,0x0c,0x00,0x00,0x77,0x7c,0x00,0x00,
+	0x00,0x0c,0x00,0x00,0x7c,0xf6,0x00,0x00,0x00,0x0c,0x00,0x01,0xe4,0xf2,0x00,0x00,
+	0x00,0x3c,0x00,0x01,0xe0,0xe3,0x00,0x00,0x01,0xbc,0x00,0x03,0x80,0x21,0x00,0x00,
+	0x01,0xfc,0x00,0x06,0xc0,0x31,0x00,0x00,0x0f,0xe4,0x00,0x18,0x80,0x71,0x80,0x00,
+	0x07,0xc7,0x20,0x71,0xff,0xf1,0x80,0x00,0x0e,0x03,0xf0,0xc1,0xd8,0x61,0x80,0x00,
+	0x1c,0x01,0xe7,0x00,0x0c,0xc1,0x80,0x00,0x1c,0x07,0xf8,0x00,0x07,0x00,0xc0,0x00,
+	0x07,0x0e,0x08,0x00,0x00,0x00,0x60,0x00,0x01,0xf0,0x08,0x00,0x00,0x00,0x30,0x00,
+	0x00,0x00,0x0c,0x00,0x02,0x00,0x30,0x00,0x00,0x00,0x07,0x00,0x06,0x00,0x10,0x00,
+	0x00,0x00,0x07,0xe0,0x1f,0x00,0x18,0x00,0x00,0x00,0x06,0x3f,0xf1,0x80,0x1c,0x00,
+	0x00,0x00,0x06,0x01,0xc0,0xe0,0x04,0x00,0x00,0x00,0x06,0x00,0xc0,0x7e,0x06,0x00,
+	0x00,0x00,0x02,0x00,0x40,0x1c,0x1e,0x00,0x00,0x00,0x03,0x00,0x60,0x18,0x7f,0x00,
+	0x00,0x00,0x01,0x80,0x70,0x0d,0xbe,0x00,0x00,0x00,0x00,0xe0,0x10,0x07,0xf8,0x00,
+	0x00,0x00,0x00,0x7c,0x10,0x01,0xe0,0x00,0x00,0x00,0x00,0x10,0x18,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x18,0xf8,0x00,0x00,0x00,0x00,0x00,0x00,0x0f,0xfc,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x07,0xf8,0x00,0x00,0x00,0x00,0x00,0x00,0x03,0xf0,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0xf0,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+	0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
+};
+
+int st7585_show_logo(libusb_device_handle *dev)
+{
+	st7585_configure_panel(dev, &hero4_lcd_hw_info);
+	st7585_upload_bitmap(dev, &hero4_lcd_hw_info, boot_logo);
+
+	/* Turn on panel */
+	st7585_spi_send_word(dev, &hero4_lcd_hw_info, 0x20);
+	st7585_spi_send_word(dev, &hero4_lcd_hw_info, 0x0c);
+	st7585_spi_send_word(dev, &hero4_lcd_hw_info, 0x8d);
+}
diff --git a/gp_lcd.h b/gp_lcd.h
@@ -0,0 +1,3 @@
+/* Short and to the point */
+
+int st7585_show_logo(libusb_device_handle *dev);