LXR uboot/drivers/video/hitachi_tx18d42vm

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Hitachi tx18d42vm LVDS LCD panel driver
   4 *
   5 * (C) Copyright 2015 Hans de Goede <hdegoede@redhat.com>
   6 */
   7
   8#include <common.h>
   9#include <malloc.h>
  10#include <linux/delay.h>
  11
  12#include <asm/gpio.h>
  13#include <errno.h>
  14
  15/*
  16 * Very simple write only SPI support, this does not use the generic SPI infra
  17 * because that assumes R/W SPI, requiring a MISO pin. Also the necessary glue
  18 * code alone would be larger then this minimal version.
  19 */
  20static void lcd_panel_spi_write(int cs, int clk, int mosi,
  21                                unsigned int data, int bits)
  22{
  23        int i, offset;
  24
  25        gpio_direction_output(cs, 0);
  26        for (i = 0; i < bits; i++) {
  27                gpio_direction_output(clk, 0);
  28                offset = (bits - 1) - i;
  29                gpio_direction_output(mosi, (data >> offset) & 1);
  30                udelay(2);
  31                gpio_direction_output(clk, 1);
  32                udelay(2);
  33        }
  34        gpio_direction_output(cs, 1);
  35        udelay(2);
  36}
  37
  38int hitachi_tx18d42vm_init(void)
  39{
  40        const u16 init_data[] = {
  41                0x0029,         /* reset */
  42                0x0025,         /* standby */
  43                0x0840,         /* enable normally black */
  44                0x0430,         /* enable FRC/dither */
  45                0x385f,         /* enter test mode(1) */
  46                0x3ca4,         /* enter test mode(2) */
  47                0x3409,         /* enable SDRRS, enlarge OE width */
  48                0x4041,         /* adopt 2 line / 1 dot */
  49        };
  50        int i, cs, clk, mosi, ret = 0;
  51
  52        cs = sunxi_name_to_gpio(CONFIG_VIDEO_LCD_SPI_CS);
  53        clk = sunxi_name_to_gpio(CONFIG_VIDEO_LCD_SPI_SCLK);
  54        mosi = sunxi_name_to_gpio(CONFIG_VIDEO_LCD_SPI_MOSI);
  55
  56        if (cs == -1 || clk == -1 || mosi == 1) {
  57                printf("Error tx18d42vm spi gpio config is invalid\n");
  58                return -EINVAL;
  59        }
  60
  61        if (gpio_request(cs, "tx18d42vm-spi-cs") != 0 ||
  62            gpio_request(clk, "tx18d42vm-spi-clk") != 0 ||
  63            gpio_request(mosi, "tx18d42vm-spi-mosi") != 0) {
  64                printf("Error cannot request tx18d42vm spi gpios\n");
  65                ret = -EBUSY;
  66                goto out;
  67        }
  68
  69        for (i = 0; i < ARRAY_SIZE(init_data); i++)
  70                lcd_panel_spi_write(cs, clk, mosi, init_data[i], 16);
  71
  72        mdelay(50); /* All the tx18d42vm drivers have a delay here ? */
  73
  74        lcd_panel_spi_write(cs, clk, mosi, 0x00ad, 16); /* display on */
  75
  76out:
  77        gpio_free(mosi);
  78        gpio_free(clk);
  79        gpio_free(cs);
  80
  81        return ret;
  82}
  83