hw/ssd0303.c

   1 /*
   2  * SSD0303 OLED controller with OSRAM Pictiva 96x16 display.
   3  *
   4  * Copyright (c) 2006-2007 CodeSourcery.
   5  * Written by Paul Brook
   6  *
   7  * This code is licenced under the GPL.
   8  */
   9
  10 /* The controller can support a variety of different displays, but we only
  11    implement one.  Most of the commends relating to brightness and geometry
  12    setup are ignored. */
  13 #include "hw.h"
  14 #include "i2c.h"
  15 #include "console.h"
  16
  17 //#define DEBUG_SSD0303 1
  18
  19 #ifdef DEBUG_SSD0303
  20 #define DPRINTF(fmt, args...) \
  21 do { printf("ssd0303: " fmt , ##args); } while (0)
  22 #define BADF(fmt, args...) \
  23 do { fprintf(stderr, "ssd0303: error: " fmt , ##args); exit(1);} while (0)
  24 #else
  25 #define DPRINTF(fmt, args...) do {} while(0)
  26 #define BADF(fmt, args...) \
  27 do { fprintf(stderr, "ssd0303: error: " fmt , ##args);} while (0)
  28 #endif
  29
  30 /* Scaling factor for pixels.  */
  31 #define MAGNIFY 4
  32
  33 enum ssd0303_mode
  34 {
  35     SSD0303_IDLE,
  36     SSD0303_DATA,
  37     SSD0303_CMD
  38 };
  39
  40 enum ssd0303_cmd {
  41     SSD0303_CMD_NONE,
  42     SSD0303_CMD_SKIP1
  43 };
  44
  45 typedef struct {
  46     i2c_slave i2c;
  47     DisplayState *ds;
  48     int row;
  49     int col;
  50     int start_line;
  51     int mirror;
  52     int flash;
  53     int enabled;
  54     int inverse;
  55     int redraw;
  56     enum ssd0303_mode mode;
  57     enum ssd0303_cmd cmd_state;
  58     uint8_t framebuffer[132*8];
  59 } ssd0303_state;
  60
  61 static int ssd0303_recv(i2c_slave *i2c)
  62 {
  63     BADF("Reads not implemented\n");
  64     return -1;
  65 }
  66
  67 static int ssd0303_send(i2c_slave *i2c, uint8_t data)
  68 {
  69     ssd0303_state *s = (ssd0303_state *)i2c;
  70     enum ssd0303_cmd old_cmd_state;
  71     switch (s->mode) {
  72     case SSD0303_IDLE:
  73         DPRINTF("byte 0x%02x\n", data);
  74         if (data == 0x80)
  75             s->mode = SSD0303_CMD;
  76         else if (data == 0x40)
  77             s->mode = SSD0303_DATA;
  78         else
  79             BADF("Unexpected byte 0x%x\n", data);
  80         break;
  81     case SSD0303_DATA:
  82         DPRINTF("data 0x%02x\n", data);
  83         if (s->col < 132) {
  84             s->framebuffer[s->col + s->row * 132] = data;
  85             s->col++;
  86             s->redraw = 1;
  87         }
  88         break;
  89     case SSD0303_CMD:
  90         old_cmd_state = s->cmd_state;
  91         s->cmd_state = SSD0303_CMD_NONE;
  92         switch (old_cmd_state) {
  93         case SSD0303_CMD_NONE:
  94             DPRINTF("cmd 0x%02x\n", data);
  95             s->mode = SSD0303_IDLE;
  96             switch (data) {
  97             case 0x00 ... 0x0f: /* Set lower colum address.  */
  98                 s->col = (s->col & 0xf0) | (data & 0xf);
  99                 break;
 100             case 0x10 ... 0x20: /* Set higher column address.  */
 101                 s->col = (s->col & 0x0f) | ((data & 0xf) << 4);
 102                 break;
 103             case 0x40 ... 0x7f: /* Set start line.  */
 104                 s->start_line = 0;
 105                 break;
 106             case 0x81: /* Set contrast (Ignored).  */
 107                 s->cmd_state = SSD0303_CMD_SKIP1;
 108                 break;
 109             case 0xa0: /* Mirror off.  */
 110                 s->mirror = 0;
 111                 break;
 112             case 0xa1: /* Mirror off.  */
 113                 s->mirror = 1;
 114                 break;
 115             case 0xa4: /* Entire display off.  */
 116                 s->flash = 0;
 117                 break;
 118             case 0xa5: /* Entire display on.  */
 119                 s->flash = 1;
 120                 break;
 121             case 0xa6: /* Inverse off.  */
 122                 s->inverse = 0;
 123                 break;
 124             case 0xa7: /* Inverse on.  */
 125                 s->inverse = 1;
 126                 break;
 127             case 0xa8: /* Set multipled ratio (Ignored).  */
 128                 s->cmd_state = SSD0303_CMD_SKIP1;
 129                 break;
 130             case 0xad: /* DC-DC power control.  */
 131                 s->cmd_state = SSD0303_CMD_SKIP1;
 132                 break;
 133             case 0xae: /* Display off.  */
 134                 s->enabled = 0;
 135                 break;
 136             case 0xaf: /* Display on.  */
 137                 s->enabled = 1;
 138                 break;
 139             case 0xb0 ... 0xbf: /* Set Page address.  */
 140                 s->row = data & 7;
 141                 break;
 142             case 0xc0 ... 0xc8: /* Set COM output direction (Ignored).  */
 143                 break;
 144             case 0xd3: /* Set display offset (Ignored).  */
 145                 s->cmd_state = SSD0303_CMD_SKIP1;
 146                 break;
 147             case 0xd5: /* Set display clock (Ignored).  */
 148                 s->cmd_state = SSD0303_CMD_SKIP1;
 149                 break;
 150             case 0xd8: /* Set color and power mode (Ignored).  */
 151                 s->cmd_state = SSD0303_CMD_SKIP1;
 152                 break;
 153             case 0xd9: /* Set pre-charge period (Ignored).  */
 154                 s->cmd_state = SSD0303_CMD_SKIP1;
 155                 break;
 156             case 0xda: /* Set COM pin configuration (Ignored).  */
 157                 s->cmd_state = SSD0303_CMD_SKIP1;
 158                 break;
 159             case 0xdb: /* Set VCOM dselect level (Ignored).  */
 160                 s->cmd_state = SSD0303_CMD_SKIP1;
 161                 break;
 162             case 0xe3: /* no-op.  */
 163                 break;
 164             default:
 165                 BADF("Unknown command: 0x%x\n", data);
 166             }
 167             break;
 168         case SSD0303_CMD_SKIP1:
 169             DPRINTF("skip 0x%02x\n", data);
 170             break;
 171         }
 172         break;
 173     }
 174     return 0;
 175 }
 176
 177 static void ssd0303_event(i2c_slave *i2c, enum i2c_event event)
 178 {
 179     ssd0303_state *s = (ssd0303_state *)i2c;
 180     switch (event) {
 181     case I2C_FINISH:
 182         s->mode = SSD0303_IDLE;
 183         break;
 184     case I2C_START_RECV:
 185     case I2C_START_SEND:
 186     case I2C_NACK:
 187         /* Nothing to do.  */
 188         break;
 189     }
 190 }
 191
 192 static void ssd0303_update_display(void *opaque)
 193 {
 194     ssd0303_state *s = (ssd0303_state *)opaque;
 195     uint8_t *dest;
 196     uint8_t *src;
 197     int x;
 198     int y;
 199     int line;
 200     char *colors[2];
 201     char colortab[MAGNIFY * 8];
 202     int dest_width;
 203     uint8_t mask;
 204
 205     if (s->redraw) {
 206         switch (s->ds->depth) {
 207         case 0:
 208             return;
 209         case 15:
 210             dest_width = 2;
 211             break;
 212         case 16:
 213             dest_width = 2;
 214             break;
 215         case 24:
 216             dest_width = 3;
 217             break;
 218         case 32:
 219             dest_width = 4;
 220             break;
 221         default:
 222             BADF("Bad color depth\n");
 223             return;
 224         }
 225         dest_width *= MAGNIFY;
 226         memset(colortab, 0xff, dest_width);
 227         memset(colortab + dest_width, 0, dest_width);
 228         if (s->flash) {
 229             colors[0] = colortab;
 230             colors[1] = colortab;
 231         } else if (s->inverse) {
 232             colors[0] = colortab;
 233             colors[1] = colortab + dest_width;
 234         } else {
 235             colors[0] = colortab + dest_width;
 236             colors[1] = colortab;
 237         }
 238         dest = s->ds->data;
 239         for (y = 0; y < 16; y++) {
 240             line = (y + s->start_line) & 63;
 241             src = s->framebuffer + 132 * (line >> 3) + 36;
 242             mask = 1 << (line & 7);
 243             for (x = 0; x < 96; x++) {
 244                 memcpy(dest, colors[(*src & mask) != 0], dest_width);
 245                 dest += dest_width;
 246                 src++;
 247             }
 248             for (x = 1; x < MAGNIFY; x++) {
 249                 memcpy(dest, dest - dest_width * 96, dest_width * 96);
 250                 dest += dest_width * 96;
 251             }
 252         }
 253     }
 254     dpy_update(s->ds, 0, 0, 96 * MAGNIFY, 16 * MAGNIFY);
 255 }
 256
 257 static void ssd0303_invalidate_display(void * opaque)
 258 {
 259     ssd0303_state *s = (ssd0303_state *)opaque;
 260     s->redraw = 1;
 261 }
 262
 263 void ssd0303_init(DisplayState *ds, i2c_bus *bus, int address)
 264 {
 265     ssd0303_state *s;
 266
 267     s = (ssd0303_state *)i2c_slave_init(bus, address, sizeof(ssd0303_state));
 268     s->ds = ds;
 269     s->i2c.event = ssd0303_event;
 270     s->i2c.recv = ssd0303_recv;
 271     s->i2c.send = ssd0303_send;
 272     graphic_console_init(ds, ssd0303_update_display, ssd0303_invalidate_display,
 273                          NULL, s);
 274     dpy_resize(s->ds, 96 * MAGNIFY, 16 * MAGNIFY);
 275 }