1/*
  2
  3MIT License
  4
  5Copyright (c) 2021 David Schramm
  6
  7Permission is hereby granted, free of charge, to any person obtaining a copy
  8of this software and associated documentation files (the "Software"), to deal
  9in the Software without restriction, including without limitation the rights
 10to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 11copies of the Software, and to permit persons to whom the Software is
 12furnished to do so, subject to the following conditions:
 13
 14The above copyright notice and this permission notice shall be included in all
 15copies or substantial portions of the Software.
 16
 17THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 18IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 19FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 20AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 21LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 22OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 23SOFTWARE.
 24*/
 25
 26#include <pico/stdlib.h>
 27#include <hardware/i2c.h>
 28#include <pico/binary_info.h>
 29#include <stdlib.h>
 30#include <string.h>
 31#include <stdio.h>
 32
 33#include "ssd1306.h"
 34#include "font.h"
 35
 36inline static void swap(uint32_t *a, uint32_t *b) {
 37    uint32_t *t=a;
 38    *a=*b;
 39    *b=*t;
 40}
 41
 42inline static void fancy_write(i2c_inst_t *i2c, uint8_t addr, const uint8_t *src, size_t len, char *name) {
 43    switch(i2c_write_blocking(i2c, addr, src, len, false)) {
 44    case PICO_ERROR_GENERIC:
 45        printf("[%s] addr not acknowledged!\n", name);
 46        break;
 47    case PICO_ERROR_TIMEOUT:
 48        printf("[%s] timeout!\n", name);
 49        break;
 50    default:
 51        //printf("[%s] wrote successfully %lu bytes!\n", name, len);
 52        break;
 53    }
 54}
 55
 56inline static void ssd1306_write(ssd1306_t *p, uint8_t val) {
 57    uint8_t d[2]= {0x00, val};
 58    fancy_write(p->i2c_i, p->address, d, 2, "ssd1306_write");
 59}
 60
 61bool ssd1306_init(ssd1306_t *p, uint16_t width, uint16_t height, uint8_t address, i2c_inst_t *i2c_instance) {
 62    p->width=width;
 63    p->height=height;
 64    p->pages=height/8;
 65    p->address=address;
 66
 67    p->i2c_i=i2c_instance;
 68
 69
 70    p->bufsize=(p->pages)*(p->width);
 71    if((p->buffer=malloc(p->bufsize+1))==NULL) {
 72        p->bufsize=0;
 73        return false;
 74    }
 75
 76    ++(p->buffer);
 77
 78    // from https://github.com/makerportal/rpi-pico-ssd1306
 79    int8_t cmds[]= {
 80        SET_DISP | 0x00,  // off
 81        // address setting
 82        SET_MEM_ADDR,
 83        0x00,  // horizontal
 84        // resolution and layout
 85        SET_DISP_START_LINE | 0x00,
 86        SET_SEG_REMAP | 0x01,  // column addr 127 mapped to SEG0
 87        SET_MUX_RATIO,
 88        height - 1,
 89        SET_COM_OUT_DIR | 0x08,  // scan from COM[N] to COM0
 90        SET_DISP_OFFSET,
 91        0x00,
 92        SET_COM_PIN_CFG,
 93        width>2*height?0x02:0x12,
 94        // timing and driving scheme
 95        SET_DISP_CLK_DIV,
 96        0x80,
 97        SET_PRECHARGE,
 98        p->external_vcc?0x22:0xF1,
 99        SET_VCOM_DESEL,
100        0x30,  // 0.83*Vcc
101        // display
102        SET_CONTRAST,
103        0xFF,  // maximum
104        SET_ENTIRE_ON,  // output follows RAM contents
105        SET_NORM_INV,  // not inverted
106        // charge pump
107        SET_CHARGE_PUMP,
108        p->external_vcc?0x10:0x14,
109        SET_DISP | 0x01
110    };
111
112    for(size_t i=0; i<sizeof(cmds); ++i)
113        ssd1306_write(p, cmds[i]);
114
115    return true;
116}
117
118inline void ssd1306_deinit(ssd1306_t *p) {
119    free(p->buffer-1);
120}
121
122inline void ssd1306_poweroff(ssd1306_t *p) {
123    ssd1306_write(p, SET_DISP|0x00);
124}
125
126inline void ssd1306_poweron(ssd1306_t *p) {
127    ssd1306_write(p, SET_DISP|0x01);
128}
129
130inline void ssd1306_contrast(ssd1306_t *p, uint8_t val) {
131    ssd1306_write(p, SET_CONTRAST);
132    ssd1306_write(p, val);
133}
134
135inline void ssd1306_invert(ssd1306_t *p, uint8_t inv) {
136    ssd1306_write(p, SET_NORM_INV | (inv & 1));
137}
138
139inline void ssd1306_clear(ssd1306_t *p) {
140    memset(p->buffer, 0, p->bufsize);
141}
142
143void ssd1306_draw_pixel(ssd1306_t *p, uint32_t x, uint32_t y) {
144    if(x>=p->width || y>=p->height) return;
145
146    p->buffer[x+p->width*(y>>3)]|=0x1<<(y&0x07); // y>>3==y/8 && y&0x7==y%8
147}
148
149void ssd1306_draw_line(ssd1306_t *p, int32_t x1, int32_t y1, int32_t x2, int32_t y2) {
150    if(x1>x2) {
151        swap(&x1, &x2);
152        swap(&y1, &y2);
153    }
154
155    if(x1==x2) {
156        if(y1>y2)
157            swap(&y1, &y2);
158        for(int32_t i=y1; i<=y2; ++i)
159            ssd1306_draw_pixel(p, x1, i);
160        return;
161    }
162
163    float m=(float) (y2-y1) / (float) (x2-x1);
164
165    for(int32_t i=x1; i<=x2; ++i) {
166        float y=m*(float) (i-x1)+(float) y1;
167        ssd1306_draw_pixel(p, i, (uint32_t) y);
168    }
169}
170
171void ssd1306_draw_square(ssd1306_t *p, uint32_t x, uint32_t y, uint32_t width, uint32_t height) {
172    for(uint32_t i=0; i<width; ++i)
173        for(uint32_t j=0; j<height; ++j)
174            ssd1306_draw_pixel(p, x+i, y+j);
175
176}
177
178void ssd13606_draw_empty_square(ssd1306_t *p, uint32_t x, uint32_t y, uint32_t width, uint32_t height) {
179    ssd1306_draw_line(p, x, y, x+width, y);
180    ssd1306_draw_line(p, x, y+height, x+width, y+height);
181    ssd1306_draw_line(p, x, y, x, y+height);
182    ssd1306_draw_line(p, x+width, y, x+width, y+height);
183}
184
185void ssd1306_draw_char_with_font(ssd1306_t *p, uint32_t x, uint32_t y, uint32_t scale, const uint8_t *font, char c) {
186    if(c > '~')
187        return;
188
189    for(uint8_t i=0; i<font[1]; ++i) {
190        uint8_t line=(uint8_t)(font[(c-0x20)*font[1]+i+2]);
191
192        for(int8_t j=0; j<font[0]; ++j, line>>=1) {
193            if(line & 1 ==1)
194                ssd1306_draw_square(p, x+i*scale, y+j*scale, scale, scale);
195        }
196    }
197}
198
199void ssd1306_draw_string_with_font(ssd1306_t *p, uint32_t x, uint32_t y, uint32_t scale, const uint8_t *font, char *s) {
200    for(int32_t x_n=x; *s; x_n+=font[0]*scale) {
201        ssd1306_draw_char_with_font(p, x_n, y, scale, font, *(s++));
202    }
203}
204
205void ssd1306_draw_char(ssd1306_t *p, uint32_t x, uint32_t y, uint32_t scale, char c) {
206    ssd1306_draw_char_with_font(p, x, y, scale, font_8x5, c);
207}
208
209void ssd1306_draw_string(ssd1306_t *p, uint32_t x, uint32_t y, uint32_t scale, char *s) {
210    ssd1306_draw_string_with_font(p, x, y, scale, font_8x5, s);
211}
212
213static inline uint32_t ssd1306_bmp_get_val(const uint8_t *data, const size_t offset, uint8_t size) {
214    switch(size) {
215    case 1:
216        return data[offset];
217    case 2:
218        return data[offset]|(data[offset+1]<<8);
219    case 4:
220        return data[offset]|(data[offset+1]<<8)|(data[offset+2]<<16)|(data[offset+3]<<24);
221    default:
222        __builtin_unreachable();
223    }
224    __builtin_unreachable();
225}
226
227void ssd1306_bmp_show_image_with_offset(ssd1306_t *p, const uint8_t *data, const long size, uint32_t x_offset, uint32_t y_offset) {
228    if(size<54) // data smaller than header
229        return;
230
231    const uint32_t bfOffBits=ssd1306_bmp_get_val(data, 10, 4);
232    const uint32_t biSize=ssd1306_bmp_get_val(data, 14, 4);
233    const int32_t biWidth=(int32_t) ssd1306_bmp_get_val(data, 18, 4);
234    const int32_t biHeight=(int32_t) ssd1306_bmp_get_val(data, 22, 4);
235    const uint16_t biBitCount=(uint16_t) ssd1306_bmp_get_val(data, 28, 2);
236    const uint32_t biCompression=ssd1306_bmp_get_val(data, 30, 4);
237
238    if(biBitCount!=1) // image not monochrome
239        return;
240
241    if(biCompression!=0) // image compressed
242        return;
243
244    const int table_start=14+biSize;
245    uint8_t color_val;
246
247    for(uint8_t i=0; i<2; ++i) {
248        if(!((data[table_start+i*4]<<16)|(data[table_start+i*4+1]<<8)|data[table_start+i*4+2])) {
249            color_val=i;
250            break;
251        }
252    }
253
254    uint32_t bytes_per_line=(biWidth/8)+(biWidth&7?1:0);
255    if(bytes_per_line&3)
256        bytes_per_line=(bytes_per_line^(bytes_per_line&3))+4;
257
258    const uint8_t *img_data=data+bfOffBits;
259
260    int step=biHeight>0?-1:1;
261    int border=biHeight>0?-1:biHeight;
262    for(uint32_t y=biHeight>0?biHeight-1:0; y!=border; y+=step) {
263        for(uint32_t x=0; x<biWidth; ++x) {
264            if(((img_data[x>>3]>>(7-(x&7)))&1)==color_val)
265                ssd1306_draw_pixel(p, x_offset+x, y_offset+y);
266        }
267        img_data+=bytes_per_line;
268    }
269}
270
271inline void ssd1306_bmp_show_image(ssd1306_t *p, const uint8_t *data, const long size) {
272    ssd1306_bmp_show_image_with_offset(p, data, size, 0, 0);
273}
274
275void ssd1306_show(ssd1306_t *p) {
276    uint8_t payload[]= {SET_COL_ADDR, 0, p->width-1, SET_PAGE_ADDR, 0, p->pages-1};
277    if(p->width==64) {
278        payload[1]+=32;
279        payload[2]+=32;
280    }
281
282    for(size_t i=0; i<sizeof(payload); ++i)
283        ssd1306_write(p, payload[i]);
284
285    *(p->buffer-1)=0x40;
286
287    fancy_write(p->i2c_i, p->address, p->buffer-1, p->bufsize+1, "ssd1306_show");
288}