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 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 19 */ 20 21 #include <linux/module.h> 22 #include <linux/kernel.h> 23 #include <linux/init.h> 24 25 #include "fbtft.h" 26 27 #define DRVNAME "fb_st7735r" 28 #define DEFAULT_GAMMA "0F 1A 0F 18 2F 28 20 22 1F 1B 23 37 00 07 02 10\n" \ 29 "0F 1B 0F 17 33 2C 29 2E 30 30 39 3F 00 07 03 10" 30 31 32 static int default_init_sequence[] = { 33 /* SWRESET - Software reset */ 34 -1, 0x01, 35 -2, 150, /* delay */ 36 37 /* SLPOUT - Sleep out & booster on */ 38 -1, 0x11, 39 -2, 500, /* delay */ 40 41 /* FRMCTR1 - frame rate control: normal mode 42 frame rate = fosc / (1 x 2 + 40) * (LINE + 2C + 2D) */ 43 -1, 0xB1, 0x01, 0x2C, 0x2D, 44 45 /* FRMCTR2 - frame rate control: idle mode 46 frame rate = fosc / (1 x 2 + 40) * (LINE + 2C + 2D) */ 47 -1, 0xB2, 0x01, 0x2C, 0x2D, 48 49 /* FRMCTR3 - frame rate control - partial mode 50 dot inversion mode, line inversion mode */ 51 -1, 0xB3, 0x01, 0x2C, 0x2D, 0x01, 0x2C, 0x2D, 52 53 /* INVCTR - display inversion control 54 no inversion */ 55 -1, 0xB4, 0x07, 56 57 /* PWCTR1 - Power Control 58 -4.6V, AUTO mode */ 59 -1, 0xC0, 0xA2, 0x02, 0x84, 60 61 /* PWCTR2 - Power Control 62 VGH25 = 2.4C VGSEL = -10 VGH = 3 * AVDD */ 63 -1, 0xC1, 0xC5, 64 65 /* PWCTR3 - Power Control 66 Opamp current small, Boost frequency */ 67 -1, 0xC2, 0x0A, 0x00, 68 69 /* PWCTR4 - Power Control 70 BCLK/2, Opamp current small & Medium low */ 71 -1, 0xC3,0x8A,0x2A, 72 73 /* PWCTR5 - Power Control */ 74 -1, 0xC4, 0x8A, 0xEE, 75 76 /* VMCTR1 - Power Control */ 77 -1, 0xC5, 0x0E, 78 79 /* INVOFF - Display inversion off */ 80 -1, 0x20, 81 82 /* COLMOD - Interface pixel format */ 83 -1, 0x3A, 0x05, 84 85 /* DISPON - Display On */ 86 -1, 0x29, 87 -2, 100, /* delay */ 88 89 /* NORON - Partial off (Normal) */ 90 -1, 0x13, 91 -2, 10, /* delay */ 92 93 /* end marker */ 94 -3 95 }; 96 97 static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) 98 { 99 fbtft_par_dbg(DEBUG_SET_ADDR_WIN, par, 100 "%s(xs=%d, ys=%d, xe=%d, ye=%d)\n", __func__, xs, ys, xe, ye); 101 102 /* Column address */ 103 write_reg(par, 0x2A, xs >> 8, xs & 0xFF, xe >> 8, xe & 0xFF); 104 105 /* Row adress */ 106 write_reg(par, 0x2B, ys >> 8, ys & 0xFF, ye >> 8, ye & 0xFF); 107 108 /* Memory write */ 109 write_reg(par, 0x2C); 110 } 111 112 #define MY (1 << 7) 113 #define MX (1 << 6) 114 #define MV (1 << 5) 115 static int set_var(struct fbtft_par *par) 116 { 117 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); 118 119 /* MADCTL - Memory data access control 120 RGB/BGR: 121 1. Mode selection pin SRGB 122 RGB H/W pin for color filter setting: 0=RGB, 1=BGR 123 2. MADCTL RGB bit 124 RGB-BGR ORDER color filter panel: 0=RGB, 1=BGR */ 125 switch (par->info->var.rotate) { 126 case 0: 127 write_reg(par, 0x36, MX | MY | (par->bgr << 3)); 128 break; 129 case 270: 130 write_reg(par, 0x36, MY | MV | (par->bgr << 3)); 131 break; 132 case 180: 133 write_reg(par, 0x36, (par->bgr << 3)); 134 break; 135 case 90: 136 write_reg(par, 0x36, MX | MV | (par->bgr << 3)); 137 break; 138 } 139 140 return 0; 141 } 142 143 /* 144 Gamma string format: 145 VRF0P VOS0P PK0P PK1P PK2P PK3P PK4P PK5P PK6P PK7P PK8P PK9P SELV0P SELV1P SELV62P SELV63P 146 VRF0N VOS0N PK0N PK1N PK2N PK3N PK4N PK5N PK6N PK7N PK8N PK9N SELV0N SELV1N SELV62N SELV63N 147 */ 148 #define CURVE(num, idx) curves[num*par->gamma.num_values + idx] 149 static int set_gamma(struct fbtft_par *par, unsigned long *curves) 150 { 151 int i,j; 152 153 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); 154 155 /* apply mask */ 156 for (i = 0; i < par->gamma.num_curves; i++) 157 for (j = 0; j < par->gamma.num_values; j++) 158 CURVE(i,j) &= 0b111111; 159 160 for (i = 0; i < par->gamma.num_curves; i++) 161 write_reg(par, 0xE0 + i, 162 CURVE(i, 0), CURVE(i, 1), CURVE(i, 2), CURVE(i, 3), 163 CURVE(i, 4), CURVE(i, 5), CURVE(i, 6), CURVE(i, 7), 164 CURVE(i, 8), CURVE(i, 9), CURVE(i, 10), CURVE(i, 11), 165 CURVE(i, 12), CURVE(i, 13), CURVE(i, 14), CURVE(i,15)); 166 167 return 0; 168 } 169 #undef CURVE 170 171 172 static struct fbtft_display display = { 173 .regwidth = 8, 174 .width = 128, 175 .height = 160, 176 .init_sequence = default_init_sequence, 177 .gamma_num = 2, 178 .gamma_len = 16, 179 .gamma = DEFAULT_GAMMA, 180 .fbtftops = { 181 .set_addr_win = set_addr_win, 182 .set_var = set_var, 183 .set_gamma = set_gamma, 184 }, 185 }; 186 FBTFT_REGISTER_DRIVER(DRVNAME, "sitronix,st7735r", &display); 187 188 MODULE_ALIAS("spi:" DRVNAME); 189 MODULE_ALIAS("platform:" DRVNAME); 190 MODULE_ALIAS("spi:st7735r"); 191 MODULE_ALIAS("platform:st7735r"); 192 193 MODULE_DESCRIPTION("FB driver for the ST7735R LCD Controller"); 194 MODULE_AUTHOR("Noralf Tronnes"); 195 MODULE_LICENSE("GPL"); 196