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
init_display(struct fbtft_par * par)24 static 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
set_addr_win(struct fbtft_par * par,int xs,int ys,int xe,int ye)55 static 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
write_reg8_bus8(struct fbtft_par * par,int len,...)64 static 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 */
set_gamma(struct fbtft_par * par,unsigned long * curves)131 static 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
blank(struct fbtft_par * par,bool on)168 static 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
180 static 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
196 FBTFT_REGISTER_DRIVER(DRVNAME, "solomon,ssd1331", &display);
197
198 MODULE_ALIAS("spi:" DRVNAME);
199 MODULE_ALIAS("platform:" DRVNAME);
200 MODULE_ALIAS("spi:ssd1331");
201 MODULE_ALIAS("platform:ssd1331");
202
203 MODULE_DESCRIPTION("SSD1331 OLED Driver");
204 MODULE_AUTHOR("Alec Smecher (adapted from SSD1351 by James Davies)");
205 MODULE_LICENSE("GPL");
206