1/*
2 * auok190xfb.c -- FB driver for AUO-K1901 controllers
3 *
4 * Copyright (C) 2011, 2012 Heiko Stuebner <heiko@sntech.de>
5 *
6 * based on broadsheetfb.c
7 *
8 * Copyright (C) 2008, Jaya Kumar
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 *
14 * Layout is based on skeletonfb.c by James Simmons and Geert Uytterhoeven.
15 *
16 * This driver is written to be used with the AUO-K1901 display controller.
17 *
18 * It is intended to be architecture independent. A board specific driver
19 * must be used to perform all the physical IO interactions.
20 *
21 * The controller supports different update modes:
22 * mode0+1 16 step gray (4bit)
23 * mode2+3 4 step gray (2bit)
24 * mode4+5 2 step gray (1bit)
25 * - mode4 is described as "without LUT"
26 * mode7 automatic selection of update mode
27 *
28 * The most interesting difference to the K1900 is the ability to do screen
29 * updates in an asynchronous fashion. Where the K1900 needs to wait for the
30 * current update to complete, the K1901 can process later updates already.
31 */
32
33#include <linux/module.h>
34#include <linux/kernel.h>
35#include <linux/errno.h>
36#include <linux/string.h>
37#include <linux/mm.h>
38#include <linux/slab.h>
39#include <linux/delay.h>
40#include <linux/interrupt.h>
41#include <linux/fb.h>
42#include <linux/init.h>
43#include <linux/platform_device.h>
44#include <linux/list.h>
45#include <linux/firmware.h>
46#include <linux/gpio.h>
47#include <linux/pm_runtime.h>
48
49#include <video/auo_k190xfb.h>
50
51#include "auo_k190x.h"
52
53/*
54 * AUO-K1901 specific commands
55 */
56
57#define AUOK1901_CMD_LUT_INTERFACE	0x0005
58#define AUOK1901_CMD_DMA_START		0x1001
59#define AUOK1901_CMD_CURSOR_START	0x1007
60#define AUOK1901_CMD_CURSOR_STOP	AUOK190X_CMD_DATA_STOP
61#define AUOK1901_CMD_DDMA_START		0x1009
62
63#define AUOK1901_INIT_GATE_PULSE_LOW	(0 << 14)
64#define AUOK1901_INIT_GATE_PULSE_HIGH	(1 << 14)
65#define AUOK1901_INIT_SINGLE_GATE	(0 << 13)
66#define AUOK1901_INIT_DOUBLE_GATE	(1 << 13)
67
68/* Bits to pixels
69 *   Mode	15-12	11-8	7-4	3-0
70 *   format2	2	T	1	T
71 *   format3	1	T	2	T
72 *   format4	T	2	T	1
73 *   format5	T	1	T	2
74 *
75 *   halftone modes:
76 *   format6	2	2	1	1
77 *   format7	1	1	2	2
78 */
79#define AUOK1901_INIT_FORMAT2		(1 << 7)
80#define AUOK1901_INIT_FORMAT3		((1 << 7) | (1 << 6))
81#define AUOK1901_INIT_FORMAT4		(1 << 8)
82#define AUOK1901_INIT_FORMAT5		((1 << 8) | (1 << 6))
83#define AUOK1901_INIT_FORMAT6		((1 << 8) | (1 << 7))
84#define AUOK1901_INIT_FORMAT7		((1 << 8) | (1 << 7) | (1 << 6))
85
86/* res[4] to bit 10
87 * res[3-0] to bits 5-2
88 */
89#define AUOK1901_INIT_RESOLUTION(_res)	(((_res & (1 << 4)) << 6) \
90					 | ((_res & 0xf) << 2))
91
92/*
93 * portrait / landscape orientation in AUOK1901_CMD_DMA_START
94 */
95#define AUOK1901_DMA_ROTATE90(_rot)		((_rot & 1) << 13)
96
97/*
98 * equivalent to 1 << 11, needs the ~ to have same rotation like K1900
99 */
100#define AUOK1901_DDMA_ROTATE180(_rot)		((~_rot & 2) << 10)
101
102static void auok1901_init(struct auok190xfb_par *par)
103{
104	struct device *dev = par->info->device;
105	struct auok190x_board *board = par->board;
106	u16 init_param = 0;
107
108	pm_runtime_get_sync(dev);
109
110	init_param |= AUOK190X_INIT_INVERSE_WHITE;
111	init_param |= AUOK190X_INIT_FORMAT0;
112	init_param |= AUOK1901_INIT_RESOLUTION(par->resolution);
113	init_param |= AUOK190X_INIT_SHIFT_LEFT;
114
115	auok190x_send_cmdargs(par, AUOK190X_CMD_INIT, 1, &init_param);
116
117	/* let the controller finish */
118	board->wait_for_rdy(par);
119
120	pm_runtime_mark_last_busy(dev);
121	pm_runtime_put_autosuspend(dev);
122}
123
124static void auok1901_update_region(struct auok190xfb_par *par, int mode,
125						u16 y1, u16 y2)
126{
127	struct device *dev = par->info->device;
128	unsigned char *buf = (unsigned char *)par->info->screen_base;
129	int xres = par->info->var.xres;
130	int line_length = par->info->fix.line_length;
131	u16 args[5];
132
133	pm_runtime_get_sync(dev);
134
135	mutex_lock(&(par->io_lock));
136
137	/* y1 and y2 must be a multiple of 2 so drop the lowest bit */
138	y1 &= 0xfffe;
139	y2 &= 0xfffe;
140
141	dev_dbg(dev, "update (x,y,w,h,mode)=(%d,%d,%d,%d,%d)\n",
142		1, y1+1, xres, y2-y1, mode);
143
144	/* K1901: first transfer the region data */
145	args[0] = AUOK1901_DMA_ROTATE90(par->rotation) | 1;
146	args[1] = y1 + 1;
147	args[2] = xres;
148	args[3] = y2 - y1;
149	buf += y1 * line_length;
150	auok190x_send_cmdargs_pixels_nowait(par, AUOK1901_CMD_DMA_START, 4,
151					    args, ((y2 - y1) * line_length)/2,
152					    (u16 *) buf);
153	auok190x_send_command_nowait(par, AUOK190X_CMD_DATA_STOP);
154
155	/* K1901: second tell the controller to update the region with mode */
156	args[0] = mode | AUOK1901_DDMA_ROTATE180(par->rotation);
157	args[1] = 1;
158	args[2] = y1 + 1;
159	args[3] = xres;
160	args[4] = y2 - y1;
161	auok190x_send_cmdargs_nowait(par, AUOK1901_CMD_DDMA_START, 5, args);
162
163	par->update_cnt++;
164
165	mutex_unlock(&(par->io_lock));
166
167	pm_runtime_mark_last_busy(dev);
168	pm_runtime_put_autosuspend(dev);
169}
170
171static void auok1901fb_dpy_update_pages(struct auok190xfb_par *par,
172						u16 y1, u16 y2)
173{
174	int mode;
175
176	if (par->update_mode < 0) {
177		mode = AUOK190X_UPDATE_MODE(1);
178		par->last_mode = -1;
179	} else {
180		mode = AUOK190X_UPDATE_MODE(par->update_mode);
181		par->last_mode = par->update_mode;
182	}
183
184	if (par->flash)
185		mode |= AUOK190X_UPDATE_NONFLASH;
186
187	auok1901_update_region(par, mode, y1, y2);
188}
189
190static void auok1901fb_dpy_update(struct auok190xfb_par *par)
191{
192	int mode;
193
194	/* When doing full updates, wait for the controller to be ready
195	 * This will hopefully catch some hangs of the K1901
196	 */
197	par->board->wait_for_rdy(par);
198
199	if (par->update_mode < 0) {
200		mode = AUOK190X_UPDATE_MODE(0);
201		par->last_mode = -1;
202	} else {
203		mode = AUOK190X_UPDATE_MODE(par->update_mode);
204		par->last_mode = par->update_mode;
205	}
206
207	if (par->flash)
208		mode |= AUOK190X_UPDATE_NONFLASH;
209
210	auok1901_update_region(par, mode, 0, par->info->var.yres);
211	par->update_cnt = 0;
212}
213
214static bool auok1901fb_need_refresh(struct auok190xfb_par *par)
215{
216	return (par->update_cnt > 10);
217}
218
219static int auok1901fb_probe(struct platform_device *pdev)
220{
221	struct auok190x_init_data init;
222	struct auok190x_board *board;
223
224	/* pick up board specific routines */
225	board = pdev->dev.platform_data;
226	if (!board)
227		return -EINVAL;
228
229	/* fill temporary init struct for common init */
230	init.id = "auo_k1901fb";
231	init.board = board;
232	init.update_partial = auok1901fb_dpy_update_pages;
233	init.update_all = auok1901fb_dpy_update;
234	init.need_refresh = auok1901fb_need_refresh;
235	init.init = auok1901_init;
236
237	return auok190x_common_probe(pdev, &init);
238}
239
240static int auok1901fb_remove(struct platform_device *pdev)
241{
242	return auok190x_common_remove(pdev);
243}
244
245static struct platform_driver auok1901fb_driver = {
246	.probe	= auok1901fb_probe,
247	.remove = auok1901fb_remove,
248	.driver	= {
249		.name	= "auo_k1901fb",
250		.pm = &auok190x_pm,
251	},
252};
253module_platform_driver(auok1901fb_driver);
254
255MODULE_DESCRIPTION("framebuffer driver for the AUO-K1901 EPD controller");
256MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
257MODULE_LICENSE("GPL");
258