1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/module.h> |
3 | #include <linux/kernel.h> |
4 | #include <linux/init.h> |
5 | #include <linux/gpio/consumer.h> |
6 | #include <linux/spi/spi.h> |
7 | #include <linux/delay.h> |
8 | |
9 | #include "fbtft.h" |
10 | |
11 | #define DRVNAME "fb_ssd1331" |
12 | #define WIDTH 96 |
13 | #define HEIGHT 64 |
14 | #define GAMMA_NUM 1 |
15 | #define GAMMA_LEN 63 |
16 | #define DEFAULT_GAMMA "0 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 2 " \ |
23 | "2 2 2 2 2 2 2" \ |
24 | |
25 | static int init_display(struct fbtft_par *par) |
26 | { |
27 | par->fbtftops.reset(par); |
28 | |
29 | write_reg(par, 0xae); /* Display Off */ |
30 | |
31 | /* Set Column Address Mapping, COM Scan Direction and Colour Depth */ |
32 | if (par->info->var.rotate == 180) |
33 | write_reg(par, 0xa0, 0x60 | (par->bgr << 2)); |
34 | else |
35 | write_reg(par, 0xa0, 0x72 | (par->bgr << 2)); |
36 | |
37 | write_reg(par, 0x72); /* RGB colour */ |
38 | write_reg(par, 0xa1, 0x00); /* Set Display Start Line */ |
39 | write_reg(par, 0xa2, 0x00); /* Set Display Offset */ |
40 | write_reg(par, 0xa4); /* NORMALDISPLAY */ |
41 | write_reg(par, 0xa8, 0x3f); /* Set multiplex */ |
42 | write_reg(par, 0xad, 0x8e); /* Set master */ |
43 | /* write_reg(par, 0xb0, 0x0b); Set power mode */ |
44 | write_reg(par, 0xb1, 0x31); /* Precharge */ |
45 | write_reg(par, 0xb3, 0xf0); /* Clock div */ |
46 | write_reg(par, 0x8a, 0x64); /* Precharge A */ |
47 | write_reg(par, 0x8b, 0x78); /* Precharge B */ |
48 | write_reg(par, 0x8c, 0x64); /* Precharge C */ |
49 | write_reg(par, 0xbb, 0x3a); /* Precharge level */ |
50 | write_reg(par, 0xbe, 0x3e); /* vcomh */ |
51 | write_reg(par, 0x87, 0x06); /* Master current */ |
52 | write_reg(par, 0x81, 0x91); /* Contrast A */ |
53 | write_reg(par, 0x82, 0x50); /* Contrast B */ |
54 | write_reg(par, 0x83, 0x7d); /* Contrast C */ |
55 | write_reg(par, 0xaf); /* Set Sleep Mode Display On */ |
56 | |
57 | return 0; |
58 | } |
59 | |
60 | static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye) |
61 | { |
62 | write_reg(par, 0x15, xs, xe); |
63 | write_reg(par, 0x75, ys, ye); |
64 | } |
65 | |
66 | static void write_reg8_bus8(struct fbtft_par *par, int len, ...) |
67 | { |
68 | va_list args; |
69 | int i, ret; |
70 | u8 *buf = par->buf; |
71 | |
72 | if (unlikely(par->debug & DEBUG_WRITE_REGISTER)) { |
73 | va_start(args, len); |
74 | for (i = 0; i < len; i++) |
75 | buf[i] = (u8)va_arg(args, unsigned int); |
76 | va_end(args); |
77 | fbtft_par_dbg_hex(DEBUG_WRITE_REGISTER, par, par->info->device, |
78 | u8, buf, len, "%s: " , __func__); |
79 | } |
80 | |
81 | va_start(args, len); |
82 | |
83 | *buf = (u8)va_arg(args, unsigned int); |
84 | gpiod_set_value(desc: par->gpio.dc, value: 0); |
85 | ret = par->fbtftops.write(par, par->buf, sizeof(u8)); |
86 | if (ret < 0) { |
87 | va_end(args); |
88 | dev_err(par->info->device, |
89 | "write() failed and returned %d\n" , ret); |
90 | return; |
91 | } |
92 | len--; |
93 | |
94 | if (len) { |
95 | i = len; |
96 | while (i--) |
97 | *buf++ = (u8)va_arg(args, unsigned int); |
98 | ret = par->fbtftops.write(par, par->buf, len * (sizeof(u8))); |
99 | if (ret < 0) { |
100 | va_end(args); |
101 | dev_err(par->info->device, |
102 | "write() failed and returned %d\n" , ret); |
103 | return; |
104 | } |
105 | } |
106 | gpiod_set_value(desc: par->gpio.dc, value: 1); |
107 | va_end(args); |
108 | } |
109 | |
110 | /* |
111 | * Grayscale Lookup Table |
112 | * GS1 - GS63 |
113 | * The driver Gamma curve contains the relative values between the entries |
114 | * in the Lookup table. |
115 | * |
116 | * From datasheet: |
117 | * 8.8 Gray Scale Decoder |
118 | * |
119 | * there are total 180 Gamma Settings (Setting 0 to Setting 180) |
120 | * available for the Gray Scale table. |
121 | * |
122 | * The gray scale is defined in incremental way, with reference |
123 | * to the length of previous table entry: |
124 | * Setting of GS1 has to be >= 0 |
125 | * Setting of GS2 has to be > Setting of GS1 +1 |
126 | * Setting of GS3 has to be > Setting of GS2 +1 |
127 | * : |
128 | * Setting of GS63 has to be > Setting of GS62 +1 |
129 | * |
130 | */ |
131 | static int set_gamma(struct fbtft_par *par, u32 *curves) |
132 | { |
133 | unsigned long tmp[GAMMA_NUM * GAMMA_LEN]; |
134 | int i, acc = 0; |
135 | |
136 | for (i = 0; i < 63; i++) { |
137 | if (i > 0 && curves[i] < 2) { |
138 | dev_err(par->info->device, |
139 | "Illegal value in Grayscale Lookup Table at index %d. Must be greater than 1\n" , |
140 | i); |
141 | return -EINVAL; |
142 | } |
143 | acc += curves[i]; |
144 | tmp[i] = acc; |
145 | if (acc > 180) { |
146 | dev_err(par->info->device, |
147 | "Illegal value(s) in Grayscale Lookup Table. At index=%d, the accumulated value has exceeded 180\n" , |
148 | i); |
149 | return -EINVAL; |
150 | } |
151 | } |
152 | |
153 | write_reg(par, 0xB8, |
154 | tmp[0], tmp[1], tmp[2], tmp[3], tmp[4], tmp[5], tmp[6], |
155 | tmp[7], tmp[8], tmp[9], tmp[10], tmp[11], tmp[12], tmp[13], |
156 | tmp[14], tmp[15], tmp[16], tmp[17], tmp[18], tmp[19], tmp[20], |
157 | tmp[21], tmp[22], tmp[23], tmp[24], tmp[25], tmp[26], tmp[27], |
158 | tmp[28], tmp[29], tmp[30], tmp[31], tmp[32], tmp[33], tmp[34], |
159 | tmp[35], tmp[36], tmp[37], tmp[38], tmp[39], tmp[40], tmp[41], |
160 | tmp[42], tmp[43], tmp[44], tmp[45], tmp[46], tmp[47], tmp[48], |
161 | tmp[49], tmp[50], tmp[51], tmp[52], tmp[53], tmp[54], tmp[55], |
162 | tmp[56], tmp[57], tmp[58], tmp[59], tmp[60], tmp[61], |
163 | tmp[62]); |
164 | |
165 | return 0; |
166 | } |
167 | |
168 | static int blank(struct fbtft_par *par, bool on) |
169 | { |
170 | fbtft_par_dbg(DEBUG_BLANK, par, "(%s=%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 | static struct fbtft_display display = { |
180 | .regwidth = 8, |
181 | .width = WIDTH, |
182 | .height = HEIGHT, |
183 | .gamma_num = GAMMA_NUM, |
184 | .gamma_len = GAMMA_LEN, |
185 | .gamma = DEFAULT_GAMMA, |
186 | .fbtftops = { |
187 | .write_register = write_reg8_bus8, |
188 | .init_display = init_display, |
189 | .set_addr_win = set_addr_win, |
190 | .set_gamma = set_gamma, |
191 | .blank = blank, |
192 | }, |
193 | }; |
194 | |
195 | FBTFT_REGISTER_DRIVER(DRVNAME, "solomon,ssd1331" , &display); |
196 | |
197 | MODULE_ALIAS("spi:" DRVNAME); |
198 | MODULE_ALIAS("platform:" DRVNAME); |
199 | MODULE_ALIAS("spi:ssd1331" ); |
200 | MODULE_ALIAS("platform:ssd1331" ); |
201 | |
202 | MODULE_DESCRIPTION("SSD1331 OLED Driver" ); |
203 | MODULE_AUTHOR("Alec Smecher (adapted from SSD1351 by James Davies)" ); |
204 | MODULE_LICENSE("GPL" ); |
205 | |