1/*
2 * FB driver for the ILI9320 LCD Controller
3 *
4 * Copyright (C) 2013 Noralf Tronnes
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20
21#include <linux/module.h>
22#include <linux/kernel.h>
23#include <linux/init.h>
24#include <linux/gpio.h>
25#include <linux/spi/spi.h>
26#include <linux/delay.h>
27
28#include "fbtft.h"
29
30#define DRVNAME		"fb_ili9320"
31#define WIDTH		240
32#define HEIGHT		320
33#define DEFAULT_GAMMA	"07 07 6 0 0 0 5 5 4 0\n" \
34			"07 08 4 7 5 1 2 0 7 7"
35
36
37static unsigned read_devicecode(struct fbtft_par *par)
38{
39	int ret;
40	u8 rxbuf[8] = {0, };
41
42	write_reg(par, 0x0000);
43	ret = par->fbtftops.read(par, rxbuf, 4);
44	return (rxbuf[2] << 8) | rxbuf[3];
45}
46
47static int init_display(struct fbtft_par *par)
48{
49	unsigned devcode;
50
51	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
52
53	par->fbtftops.reset(par);
54
55	devcode = read_devicecode(par);
56	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "Device code: 0x%04X\n",
57		devcode);
58	if ((devcode != 0x0000) && (devcode != 0x9320))
59		dev_warn(par->info->device,
60			"Unrecognized Device code: 0x%04X (expected 0x9320)\n",
61			devcode);
62
63	/* Initialization sequence from ILI9320 Application Notes */
64
65	/* *********** Start Initial Sequence ********* */
66	write_reg(par, 0x00E5, 0x8000); /* Set the Vcore voltage and this setting is must. */
67	write_reg(par, 0x0000, 0x0001); /* Start internal OSC. */
68	write_reg(par, 0x0001, 0x0100); /* set SS and SM bit */
69	write_reg(par, 0x0002, 0x0700); /* set 1 line inversion */
70	write_reg(par, 0x0004, 0x0000); /* Resize register */
71	write_reg(par, 0x0008, 0x0202); /* set the back and front porch */
72	write_reg(par, 0x0009, 0x0000); /* set non-display area refresh cycle */
73	write_reg(par, 0x000A, 0x0000); /* FMARK function */
74	write_reg(par, 0x000C, 0x0000); /* RGB interface setting */
75	write_reg(par, 0x000D, 0x0000); /* Frame marker Position */
76	write_reg(par, 0x000F, 0x0000); /* RGB interface polarity */
77
78	/* ***********Power On sequence *************** */
79	write_reg(par, 0x0010, 0x0000); /* SAP, BT[3:0], AP, DSTB, SLP, STB */
80	write_reg(par, 0x0011, 0x0007); /* DC1[2:0], DC0[2:0], VC[2:0] */
81	write_reg(par, 0x0012, 0x0000); /* VREG1OUT voltage */
82	write_reg(par, 0x0013, 0x0000); /* VDV[4:0] for VCOM amplitude */
83	mdelay(200); /* Dis-charge capacitor power voltage */
84	write_reg(par, 0x0010, 0x17B0); /* SAP, BT[3:0], AP, DSTB, SLP, STB */
85	write_reg(par, 0x0011, 0x0031); /* R11h=0x0031 at VCI=3.3V DC1[2:0], DC0[2:0], VC[2:0] */
86	mdelay(50);
87	write_reg(par, 0x0012, 0x0138); /* R12h=0x0138 at VCI=3.3V VREG1OUT voltage */
88	mdelay(50);
89	write_reg(par, 0x0013, 0x1800); /* R13h=0x1800 at VCI=3.3V VDV[4:0] for VCOM amplitude */
90	write_reg(par, 0x0029, 0x0008); /* R29h=0x0008 at VCI=3.3V VCM[4:0] for VCOMH */
91	mdelay(50);
92	write_reg(par, 0x0020, 0x0000); /* GRAM horizontal Address */
93	write_reg(par, 0x0021, 0x0000); /* GRAM Vertical Address */
94
95	/* ------------------ Set GRAM area --------------- */
96	write_reg(par, 0x0050, 0x0000); /* Horizontal GRAM Start Address */
97	write_reg(par, 0x0051, 0x00EF); /* Horizontal GRAM End Address */
98	write_reg(par, 0x0052, 0x0000); /* Vertical GRAM Start Address */
99	write_reg(par, 0x0053, 0x013F); /* Vertical GRAM Start Address */
100	write_reg(par, 0x0060, 0x2700); /* Gate Scan Line */
101	write_reg(par, 0x0061, 0x0001); /* NDL,VLE, REV */
102	write_reg(par, 0x006A, 0x0000); /* set scrolling line */
103
104	/* -------------- Partial Display Control --------- */
105	write_reg(par, 0x0080, 0x0000);
106	write_reg(par, 0x0081, 0x0000);
107	write_reg(par, 0x0082, 0x0000);
108	write_reg(par, 0x0083, 0x0000);
109	write_reg(par, 0x0084, 0x0000);
110	write_reg(par, 0x0085, 0x0000);
111
112	/* -------------- Panel Control ------------------- */
113	write_reg(par, 0x0090, 0x0010);
114	write_reg(par, 0x0092, 0x0000);
115	write_reg(par, 0x0093, 0x0003);
116	write_reg(par, 0x0095, 0x0110);
117	write_reg(par, 0x0097, 0x0000);
118	write_reg(par, 0x0098, 0x0000);
119	write_reg(par, 0x0007, 0x0173); /* 262K color and display ON */
120
121	return 0;
122}
123
124static void set_addr_win(struct fbtft_par *par, int xs, int ys, int xe, int ye)
125{
126	fbtft_par_dbg(DEBUG_SET_ADDR_WIN, par,
127		"%s(xs=%d, ys=%d, xe=%d, ye=%d)\n", __func__, xs, ys, xe, ye);
128
129	switch (par->info->var.rotate) {
130	/* R20h = Horizontal GRAM Start Address */
131	/* R21h = Vertical GRAM Start Address */
132	case 0:
133		write_reg(par, 0x0020, xs);
134		write_reg(par, 0x0021, ys);
135		break;
136	case 180:
137		write_reg(par, 0x0020, WIDTH - 1 - xs);
138		write_reg(par, 0x0021, HEIGHT - 1 - ys);
139		break;
140	case 270:
141		write_reg(par, 0x0020, WIDTH - 1 - ys);
142		write_reg(par, 0x0021, xs);
143		break;
144	case 90:
145		write_reg(par, 0x0020, ys);
146		write_reg(par, 0x0021, HEIGHT - 1 - xs);
147		break;
148	}
149	write_reg(par, 0x0022); /* Write Data to GRAM */
150}
151
152static int set_var(struct fbtft_par *par)
153{
154	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
155
156	switch (par->info->var.rotate) {
157	case 0:
158		write_reg(par, 0x3, (par->bgr << 12) | 0x30);
159		break;
160	case 270:
161		write_reg(par, 0x3, (par->bgr << 12) | 0x28);
162		break;
163	case 180:
164		write_reg(par, 0x3, (par->bgr << 12) | 0x00);
165		break;
166	case 90:
167		write_reg(par, 0x3, (par->bgr << 12) | 0x18);
168		break;
169	}
170	return 0;
171}
172
173/*
174  Gamma string format:
175    VRP0 VRP1 RP0 RP1 KP0 KP1 KP2 KP3 KP4 KP5
176    VRN0 VRN1 RN0 RN1 KN0 KN1 KN2 KN3 KN4 KN5
177*/
178#define CURVE(num, idx)  curves[num*par->gamma.num_values + idx]
179static int set_gamma(struct fbtft_par *par, unsigned long *curves)
180{
181	unsigned long mask[] = {
182		0x1f, 0x1f, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
183		0x1f, 0x1f, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
184	};
185	int i, j;
186
187	fbtft_par_dbg(DEBUG_INIT_DISPLAY, par, "%s()\n", __func__);
188
189	/* apply mask */
190	for (i = 0; i < 2; i++)
191		for (j = 0; j < 10; j++)
192			CURVE(i, j) &= mask[i*par->gamma.num_values + j];
193
194	write_reg(par, 0x0030, CURVE(0, 5) << 8 | CURVE(0, 4));
195	write_reg(par, 0x0031, CURVE(0, 7) << 8 | CURVE(0, 6));
196	write_reg(par, 0x0032, CURVE(0, 9) << 8 | CURVE(0, 8));
197	write_reg(par, 0x0035, CURVE(0, 3) << 8 | CURVE(0, 2));
198	write_reg(par, 0x0036, CURVE(0, 1) << 8 | CURVE(0, 0));
199
200	write_reg(par, 0x0037, CURVE(1, 5) << 8 | CURVE(1, 4));
201	write_reg(par, 0x0038, CURVE(1, 7) << 8 | CURVE(1, 6));
202	write_reg(par, 0x0039, CURVE(1, 9) << 8 | CURVE(1, 8));
203	write_reg(par, 0x003C, CURVE(1, 3) << 8 | CURVE(1, 2));
204	write_reg(par, 0x003D, CURVE(1, 1) << 8 | CURVE(1, 0));
205
206	return 0;
207}
208#undef CURVE
209
210
211static struct fbtft_display display = {
212	.regwidth = 16,
213	.width = WIDTH,
214	.height = HEIGHT,
215	.gamma_num = 2,
216	.gamma_len = 10,
217	.gamma = DEFAULT_GAMMA,
218	.fbtftops = {
219		.init_display = init_display,
220		.set_addr_win = set_addr_win,
221		.set_var = set_var,
222		.set_gamma = set_gamma,
223	},
224};
225FBTFT_REGISTER_DRIVER(DRVNAME, "ilitek,ili9320", &display);
226
227MODULE_ALIAS("spi:" DRVNAME);
228MODULE_ALIAS("platform:" DRVNAME);
229MODULE_ALIAS("spi:ili9320");
230MODULE_ALIAS("platform:ili9320");
231
232MODULE_DESCRIPTION("FB driver for the ILI9320 LCD Controller");
233MODULE_AUTHOR("Noralf Tronnes");
234MODULE_LICENSE("GPL");
235