1#include <linux/module.h> 2#include <linux/kernel.h> 3#include <linux/init.h> 4#include <linux/gpio.h> 5#include <linux/spi/spi.h> 6#include <linux/delay.h> 7 8#include "fbtft.h" 9 10#define DRVNAME "fb_ssd1331" 11#define WIDTH 96 12#define HEIGHT 64 13#define GAMMA_NUM 1 14#define GAMMA_LEN 63 15#define DEFAULT_GAMMA "0 2 2 2 2 2 2 2 " \ 16 "2 2 2 2 2 2 2 2 " \ 17 "2 2 2 2 2 2 2 2 " \ 18 "2 2 2 2 2 2 2 2 " \ 19 "2 2 2 2 2 2 2 2 " \ 20 "2 2 2 2 2 2 2 2 " \ 21 "2 2 2 2 2 2 2 2 " \ 22 "2 2 2 2 2 2 2" \ 23 24static int init_display(struct fbtft_par *par) 25{ 26 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); 27 28 par->fbtftops.reset(par); 29 30 write_reg(par, 0xae); /* Display Off */ 31 write_reg(par, 0xa0, 0x70 | (par->bgr << 2)); /* Set Colour Depth */ 32 write_reg(par, 0x72); /* RGB colour */ 33 write_reg(par, 0xa1, 0x00); /* Set Display Start Line */ 34 write_reg(par, 0xa2, 0x00); /* Set Display Offset */ 35 write_reg(par, 0xa4); /* NORMALDISPLAY */ 36 write_reg(par, 0xa8, 0x3f); /* Set multiplex */ 37 write_reg(par, 0xad, 0x8e); /* Set master */ 38 /* write_reg(par, 0xb0, 0x0b); Set power mode */ 39 write_reg(par, 0xb1, 0x31); /* Precharge */ 40 write_reg(par, 0xb3, 0xf0); /* Clock div */ 41 write_reg(par, 0x8a, 0x64); /* Precharge A */ 42 write_reg(par, 0x8b, 0x78); /* Precharge B */ 43 write_reg(par, 0x8c, 0x64); /* Precharge C */ 44 write_reg(par, 0xbb, 0x3a); /* Precharge level */ 45 write_reg(par, 0xbe, 0x3e); /* vcomh */ 46 write_reg(par, 0x87, 0x06); /* Master current */ 47 write_reg(par, 0x81, 0x91); /* Contrast A */ 48 write_reg(par, 0x82, 0x50); /* Contrast B */ 49 write_reg(par, 0x83, 0x7d); /* Contrast C */ 50 write_reg(par, 0xaf); /* Set Sleep Mode Display On */ 51 52 return 0; 53} 54 55static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) 56{ 57 fbtft_par_dbg(DEBUG_SET_ADDR_WIN, par, 58 "%s(xs=%d, ys=%d, xe=%d, ye=%d)\n", __func__, xs, ys, xe, ye); 59 60 write_reg(par, 0x15, xs, xe); 61 write_reg(par, 0x75, ys, ye); 62} 63 64static void write_reg8_bus8(struct fbtft_par *par, int len, ...) 65{ 66 va_list args; 67 int i, ret; 68 u8 *buf = (u8 *)par->buf; 69 70 if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) { 71 va_start(args, len); 72 for (i = 0; i < len; i++) 73 buf[i] = (u8)va_arg(args, unsigned int); 74 va_end(args); 75 fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, u8, buf, len, "%s: ", __func__); 76 } 77 78 va_start(args, len); 79 80 *buf = (u8)va_arg(args, unsigned int); 81 if (par->gpio.dc != -1) 82 gpio_set_value(par->gpio.dc, 0); 83 ret = par->fbtftops.write(par, par->buf, sizeof(u8)); 84 if (ret < 0) { 85 va_end(args); 86 dev_err(par->info->device, 87 "write() failed and returned %d\n", ret); 88 return; 89 } 90 len--; 91 92 if (len) { 93 i = len; 94 while (i--) 95 *buf++ = (u8)va_arg(args, unsigned int); 96 ret = par->fbtftops.write(par, par->buf, len * (sizeof(u8))); 97 if (ret < 0) { 98 va_end(args); 99 dev_err(par->info->device, 100 "write() failed and returned %d\n", ret); 101 return; 102 } 103 } 104 if (par->gpio.dc != -1) 105 gpio_set_value(par->gpio.dc, 1); 106 va_end(args); 107} 108 109/* 110 Grayscale Lookup Table 111 GS1 - GS63 112 The driver Gamma curve contains the relative values between the entries 113 in the Lookup table. 114 115 From datasheet: 116 8.8 Gray Scale Decoder 117 118 there are total 180 Gamma Settings (Setting 0 to Setting 180) 119 available for the Gray Scale table. 120 121 The gray scale is defined in incremental way, with reference 122 to the length of previous table entry: 123 Setting of GS1 has to be >= 0 124 Setting of GS2 has to be > Setting of GS1 +1 125 Setting of GS3 has to be > Setting of GS2 +1 126 : 127 Setting of GS63 has to be > Setting of GS62 +1 128 129 130*/ 131static int set_gamma(struct fbtft_par *par, unsigned long *curves) 132{ 133 unsigned long tmp[GAMMA_NUM * GAMMA_LEN]; 134 int i, acc = 0; 135 136 fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__); 137 138 for (i = 0; i < 63; i++) { 139 if (i > 0 && curves[i] < 2) { 140 dev_err(par->info->device, 141 "Illegal value in Grayscale Lookup Table at index %d. " \ 142 "Must be greater than 1\n", i); 143 return -EINVAL; 144 } 145 acc += curves[i]; 146 tmp[i] = acc; 147 if (acc > 180) { 148 dev_err(par->info->device, 149 "Illegal value(s) in Grayscale Lookup Table. " \ 150 "At index=%d, the accumulated value has exceeded 180\n", i); 151 return -EINVAL; 152 } 153 } 154 155 write_reg(par, 0xB8, 156 tmp[0], tmp[1], tmp[2], tmp[3], tmp[4], tmp[5], tmp[6], tmp[7], 157 tmp[8], tmp[9], tmp[10], tmp[11], tmp[12], tmp[13], tmp[14], tmp[15], 158 tmp[16], tmp[17], tmp[18], tmp[19], tmp[20], tmp[21], tmp[22], tmp[23], 159 tmp[24], tmp[25], tmp[26], tmp[27], tmp[28], tmp[29], tmp[30], tmp[31], 160 tmp[32], tmp[33], tmp[34], tmp[35], tmp[36], tmp[37], tmp[38], tmp[39], 161 tmp[40], tmp[41], tmp[42], tmp[43], tmp[44], tmp[45], tmp[46], tmp[47], 162 tmp[48], tmp[49], tmp[50], tmp[51], tmp[52], tmp[53], tmp[54], tmp[55], 163 tmp[56], tmp[57], tmp[58], tmp[59], tmp[60], tmp[61], tmp[62]); 164 165 return 0; 166} 167 168static int blank(struct fbtft_par *par, bool on) 169{ 170 fbtft_par_dbg(DEBUG_BLANK, par, "%s(blank=%s)\n", 171 __func__, on ? "true" : "false"); 172 if (on) 173 write_reg(par, 0xAE); 174 else 175 write_reg(par, 0xAF); 176 return 0; 177} 178 179 180static struct fbtft_display display = { 181 .regwidth = 8, 182 .width = WIDTH, 183 .height = HEIGHT, 184 .gamma_num = GAMMA_NUM, 185 .gamma_len = GAMMA_LEN, 186 .gamma = DEFAULT_GAMMA, 187 .fbtftops = { 188 .write_register = write_reg8_bus8, 189 .init_display = init_display, 190 .set_addr_win = set_addr_win, 191 .set_gamma = set_gamma, 192 .blank = blank, 193 }, 194}; 195 196FBTFT_REGISTER_DRIVER(DRVNAME, "solomon,ssd1331", &display); 197 198MODULE_ALIAS("spi:" DRVNAME); 199MODULE_ALIAS("platform:" DRVNAME); 200MODULE_ALIAS("spi:ssd1331"); 201MODULE_ALIAS("platform:ssd1331"); 202 203MODULE_DESCRIPTION("SSD1331 OLED Driver"); 204MODULE_AUTHOR("Alec Smecher (adapted from SSD1351 by James Davies)"); 205MODULE_LICENSE("GPL"); 206