1 /* 2 * FB driver for the ST7735R LCD Controller 3 * 4 * Copyright (C) 2013 Noralf Tronnes 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 */ 16 17 #include <linux/module.h> 18 #include <linux/kernel.h> 19 #include <linux/init.h> 20 21 #include "fbtft.h" 22 23 #define DRVNAME "fb_st7735r" 24 #define DEFAULT_GAMMA "0F 1A 0F 18 2F 28 20 22 1F 1B 23 37 00 07 02 10\n" \ 25 "0F 1B 0F 17 33 2C 29 2E 30 30 39 3F 00 07 03 10" 26 27 static int default_init_sequence[] = { 28 /* SWRESET - Software reset */ 29 -1, 0x01, 30 -2, 150, /* delay */ 31 32 /* SLPOUT - Sleep out & booster on */ 33 -1, 0x11, 34 -2, 500, /* delay */ 35 36 /* FRMCTR1 - frame rate control: normal mode 37 frame rate = fosc / (1 x 2 + 40) * (LINE + 2C + 2D) */ 38 -1, 0xB1, 0x01, 0x2C, 0x2D, 39 40 /* FRMCTR2 - frame rate control: idle mode 41 frame rate = fosc / (1 x 2 + 40) * (LINE + 2C + 2D) */ 42 -1, 0xB2, 0x01, 0x2C, 0x2D, 43 44 /* FRMCTR3 - frame rate control - partial mode 45 dot inversion mode, line inversion mode */ 46 -1, 0xB3, 0x01, 0x2C, 0x2D, 0x01, 0x2C, 0x2D, 47 48 /* INVCTR - display inversion control 49 no inversion */ 50 -1, 0xB4, 0x07, 51 52 /* PWCTR1 - Power Control 53 -4.6V, AUTO mode */ 54 -1, 0xC0, 0xA2, 0x02, 0x84, 55 56 /* PWCTR2 - Power Control 57 VGH25 = 2.4C VGSEL = -10 VGH = 3 * AVDD */ 58 -1, 0xC1, 0xC5, 59 60 /* PWCTR3 - Power Control 61 Opamp current small, Boost frequency */ 62 -1, 0xC2, 0x0A, 0x00, 63 64 /* PWCTR4 - Power Control 65 BCLK/2, Opamp current small & Medium low */ 66 -1, 0xC3, 0x8A, 0x2A, 67 68 /* PWCTR5 - Power Control */ 69 -1, 0xC4, 0x8A, 0xEE, 70 71 /* VMCTR1 - Power Control */ 72 -1, 0xC5, 0x0E, 73 74 /* INVOFF - Display inversion off */ 75 -1, 0x20, 76 77 /* COLMOD - Interface pixel format */ 78 -1, 0x3A, 0x05, 79 80 /* DISPON - Display On */ 81 -1, 0x29, 82 -2, 100, /* delay */ 83 84 /* NORON - Partial off (Normal) */ 85 -1, 0x13, 86 -2, 10, /* delay */ 87 88 /* end marker */ 89 -3 90 }; 91 92 static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) 93 { 94 /* Column address */ 95 write_reg(par, 0x2A, xs >> 8, xs & 0xFF, xe >> 8, xe & 0xFF); 96 97 /* Row address */ 98 write_reg(par, 0x2B, ys >> 8, ys & 0xFF, ye >> 8, ye & 0xFF); 99 100 /* Memory write */ 101 write_reg(par, 0x2C); 102 } 103 104 #define MY BIT(7) 105 #define MX BIT(6) 106 #define MV BIT(5) 107 static int set_var(struct fbtft_par *par) 108 { 109 /* MADCTL - Memory data access control 110 RGB/BGR: 111 1. Mode selection pin SRGB 112 RGB H/W pin for color filter setting: 0=RGB, 1=BGR 113 2. MADCTL RGB bit 114 RGB-BGR ORDER color filter panel: 0=RGB, 1=BGR */ 115 switch (par->info->var.rotate) { 116 case 0: 117 write_reg(par, 0x36, MX | MY | (par->bgr << 3)); 118 break; 119 case 270: 120 write_reg(par, 0x36, MY | MV | (par->bgr << 3)); 121 break; 122 case 180: 123 write_reg(par, 0x36, par->bgr << 3); 124 break; 125 case 90: 126 write_reg(par, 0x36, MX | MV | (par->bgr << 3)); 127 break; 128 } 129 130 return 0; 131 } 132 133 /* 134 Gamma string format: 135 VRF0P VOS0P PK0P PK1P PK2P PK3P PK4P PK5P PK6P PK7P PK8P PK9P SELV0P SELV1P SELV62P SELV63P 136 VRF0N VOS0N PK0N PK1N PK2N PK3N PK4N PK5N PK6N PK7N PK8N PK9N SELV0N SELV1N SELV62N SELV63N 137 */ 138 #define CURVE(num, idx) curves[num * par->gamma.num_values + idx] 139 static int set_gamma(struct fbtft_par *par, unsigned long *curves) 140 { 141 int i, j; 142 143 /* apply mask */ 144 for (i = 0; i < par->gamma.num_curves; i++) 145 for (j = 0; j < par->gamma.num_values; j++) 146 CURVE(i, j) &= 0x3f; 147 148 for (i = 0; i < par->gamma.num_curves; i++) 149 write_reg(par, 0xE0 + i, 150 CURVE(i, 0), CURVE(i, 1), CURVE(i, 2), CURVE(i, 3), 151 CURVE(i, 4), CURVE(i, 5), CURVE(i, 6), CURVE(i, 7), 152 CURVE(i, 8), CURVE(i, 9), CURVE(i, 10), CURVE(i, 11), 153 CURVE(i, 12), CURVE(i, 13), CURVE(i, 14), CURVE(i, 15)); 154 155 return 0; 156 } 157 #undef CURVE 158 159 static struct fbtft_display display = { 160 .regwidth = 8, 161 .width = 128, 162 .height = 160, 163 .init_sequence = default_init_sequence, 164 .gamma_num = 2, 165 .gamma_len = 16, 166 .gamma = DEFAULT_GAMMA, 167 .fbtftops = { 168 .set_addr_win = set_addr_win, 169 .set_var = set_var, 170 .set_gamma = set_gamma, 171 }, 172 }; 173 174 FBTFT_REGISTER_DRIVER(DRVNAME, "sitronix,st7735r", &display); 175 176 MODULE_ALIAS("spi:" DRVNAME); 177 MODULE_ALIAS("platform:" DRVNAME); 178 MODULE_ALIAS("spi:st7735r"); 179 MODULE_ALIAS("platform:st7735r"); 180 181 MODULE_DESCRIPTION("FB driver for the ST7735R LCD Controller"); 182 MODULE_AUTHOR("Noralf Tronnes"); 183 MODULE_LICENSE("GPL"); 184