1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * FB driver for the ST7735R LCD Controller
4 *
5 * Copyright (C) 2013 Noralf Tronnes
6 */
7
8#include <linux/module.h>
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <video/mipi_display.h>
12
13#include "fbtft.h"
14
15#define DRVNAME "fb_st7735r"
16#define DEFAULT_GAMMA   "0F 1A 0F 18 2F 28 20 22 1F 1B 23 37 00 07 02 10\n" \
17			"0F 1B 0F 17 33 2C 29 2E 30 30 39 3F 00 07 03 10"
18
19static const s16 default_init_sequence[] = {
20	-1, MIPI_DCS_SOFT_RESET,
21	-2, 150,                               /* delay */
22
23	-1, MIPI_DCS_EXIT_SLEEP_MODE,
24	-2, 500,                               /* delay */
25
26	/* FRMCTR1 - frame rate control: normal mode
27	 * frame rate = fosc / (1 x 2 + 40) * (LINE + 2C + 2D)
28	 */
29	-1, 0xB1, 0x01, 0x2C, 0x2D,
30
31	/* FRMCTR2 - frame rate control: idle mode
32	 * frame rate = fosc / (1 x 2 + 40) * (LINE + 2C + 2D)
33	 */
34	-1, 0xB2, 0x01, 0x2C, 0x2D,
35
36	/* FRMCTR3 - frame rate control - partial mode
37	 * dot inversion mode, line inversion mode
38	 */
39	-1, 0xB3, 0x01, 0x2C, 0x2D, 0x01, 0x2C, 0x2D,
40
41	/* INVCTR - display inversion control
42	 * no inversion
43	 */
44	-1, 0xB4, 0x07,
45
46	/* PWCTR1 - Power Control
47	 * -4.6V, AUTO mode
48	 */
49	-1, 0xC0, 0xA2, 0x02, 0x84,
50
51	/* PWCTR2 - Power Control
52	 * VGH25 = 2.4C VGSEL = -10 VGH = 3 * AVDD
53	 */
54	-1, 0xC1, 0xC5,
55
56	/* PWCTR3 - Power Control
57	 * Opamp current small, Boost frequency
58	 */
59	-1, 0xC2, 0x0A, 0x00,
60
61	/* PWCTR4 - Power Control
62	 * BCLK/2, Opamp current small & Medium low
63	 */
64	-1, 0xC3, 0x8A, 0x2A,
65
66	/* PWCTR5 - Power Control */
67	-1, 0xC4, 0x8A, 0xEE,
68
69	/* VMCTR1 - Power Control */
70	-1, 0xC5, 0x0E,
71
72	-1, MIPI_DCS_EXIT_INVERT_MODE,
73
74	-1, MIPI_DCS_SET_PIXEL_FORMAT, MIPI_DCS_PIXEL_FMT_16BIT,
75
76	-1, MIPI_DCS_SET_DISPLAY_ON,
77	-2, 100,                               /* delay */
78
79	-1, MIPI_DCS_ENTER_NORMAL_MODE,
80	-2, 10,                               /* delay */
81
82	/* end marker */
83	-3
84};
85
86static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
87{
88	write_reg(par, MIPI_DCS_SET_COLUMN_ADDRESS,
89		  xs >> 8, xs & 0xFF, xe >> 8, xe & 0xFF);
90
91	write_reg(par, MIPI_DCS_SET_PAGE_ADDRESS,
92		  ys >> 8, ys & 0xFF, ye >> 8, ye & 0xFF);
93
94	write_reg(par, MIPI_DCS_WRITE_MEMORY_START);
95}
96
97#define MY BIT(7)
98#define MX BIT(6)
99#define MV BIT(5)
100static int set_var(struct fbtft_par *par)
101{
102	/* MADCTL - Memory data access control
103	 * RGB/BGR:
104	 * 1. Mode selection pin SRGB
105	 *    RGB H/W pin for color filter setting: 0=RGB, 1=BGR
106	 * 2. MADCTL RGB bit
107	 *    RGB-BGR ORDER color filter panel: 0=RGB, 1=BGR
108	 */
109	switch (par->info->var.rotate) {
110	case 0:
111		write_reg(par, MIPI_DCS_SET_ADDRESS_MODE,
112			  MX | MY | (par->bgr << 3));
113		break;
114	case 270:
115		write_reg(par, MIPI_DCS_SET_ADDRESS_MODE,
116			  MY | MV | (par->bgr << 3));
117		break;
118	case 180:
119		write_reg(par, MIPI_DCS_SET_ADDRESS_MODE,
120			  par->bgr << 3);
121		break;
122	case 90:
123		write_reg(par, MIPI_DCS_SET_ADDRESS_MODE,
124			  MX | MV | (par->bgr << 3));
125		break;
126	}
127
128	return 0;
129}
130
131/*
132 * Gamma string format:
133 * VRF0P VOS0P PK0P PK1P PK2P PK3P PK4P PK5P PK6P PK7P PK8P PK9P SELV0P SELV1P SELV62P SELV63P
134 * VRF0N VOS0N PK0N PK1N PK2N PK3N PK4N PK5N PK6N PK7N PK8N PK9N SELV0N SELV1N SELV62N SELV63N
135 */
136#define CURVE(num, idx)  curves[(num) * par->gamma.num_values + (idx)]
137static int set_gamma(struct fbtft_par *par, u32 *curves)
138{
139	int i, j;
140
141	/* apply mask */
142	for (i = 0; i < par->gamma.num_curves; i++)
143		for (j = 0; j < par->gamma.num_values; j++)
144			CURVE(i, j) &= 0x3f;
145
146	for (i = 0; i < par->gamma.num_curves; i++)
147		write_reg(par, 0xE0 + i,
148			  CURVE(i, 0),  CURVE(i, 1),
149			  CURVE(i, 2),  CURVE(i, 3),
150			  CURVE(i, 4),  CURVE(i, 5),
151			  CURVE(i, 6),  CURVE(i, 7),
152			  CURVE(i, 8),  CURVE(i, 9),
153			  CURVE(i, 10), CURVE(i, 11),
154			  CURVE(i, 12), CURVE(i, 13),
155			  CURVE(i, 14), CURVE(i, 15));
156
157	return 0;
158}
159
160#undef CURVE
161
162static struct fbtft_display display = {
163	.regwidth = 8,
164	.width = 128,
165	.height = 160,
166	.init_sequence = default_init_sequence,
167	.gamma_num = 2,
168	.gamma_len = 16,
169	.gamma = DEFAULT_GAMMA,
170	.fbtftops = {
171		.set_addr_win = set_addr_win,
172		.set_var = set_var,
173		.set_gamma = set_gamma,
174	},
175};
176
177FBTFT_REGISTER_DRIVER(DRVNAME, "sitronix,st7735r", &display);
178
179MODULE_ALIAS("spi:" DRVNAME);
180MODULE_ALIAS("platform:" DRVNAME);
181MODULE_ALIAS("spi:st7735r");
182MODULE_ALIAS("platform:st7735r");
183
184MODULE_DESCRIPTION("FB driver for the ST7735R LCD Controller");
185MODULE_AUTHOR("Noralf Tronnes");
186MODULE_LICENSE("GPL");
187