1 /*
2 * linux/drivers/video/hecubafb.c -- FB driver for Hecuba/Apollo controller
3 *
4 * Copyright (C) 2006, Jaya Kumar
5 * This work was sponsored by CIS(M) Sdn Bhd
6 *
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License. See the file COPYING in the main directory of this archive for
9 * more details.
10 *
11 * Layout is based on skeletonfb.c by James Simmons and Geert Uytterhoeven.
12 * This work was possible because of apollo display code from E-Ink's website
13 * http://support.eink.com/community
14 * All information used to write this code is from public material made
15 * available by E-Ink on its support site. Some commands such as 0xA4
16 * were found by looping through cmd=0x00 thru 0xFF and supplying random
17 * values. There are other commands that the display is capable of,
18 * beyond the 5 used here but they are more complex.
19 *
20 * This driver is written to be used with the Hecuba display architecture.
21 * The actual display chip is called Apollo and the interface electronics
22 * it needs is called Hecuba.
23 *
24 * It is intended to be architecture independent. A board specific driver
25 * must be used to perform all the physical IO interactions. An example
26 * is provided as n411.c
27 *
28 */
29
30 #include <linux/module.h>
31 #include <linux/kernel.h>
32 #include <linux/errno.h>
33 #include <linux/string.h>
34 #include <linux/mm.h>
35 #include <linux/vmalloc.h>
36 #include <linux/delay.h>
37 #include <linux/interrupt.h>
38 #include <linux/fb.h>
39 #include <linux/init.h>
40 #include <linux/platform_device.h>
41 #include <linux/list.h>
42 #include <linux/uaccess.h>
43
44 #include <video/hecubafb.h>
45
46 /* Display specific information */
47 #define DPY_W 600
48 #define DPY_H 800
49
50 static const struct fb_fix_screeninfo hecubafb_fix = {
51 .id = "hecubafb",
52 .type = FB_TYPE_PACKED_PIXELS,
53 .visual = FB_VISUAL_MONO01,
54 .xpanstep = 0,
55 .ypanstep = 0,
56 .ywrapstep = 0,
57 .line_length = DPY_W,
58 .accel = FB_ACCEL_NONE,
59 };
60
61 static const struct fb_var_screeninfo hecubafb_var = {
62 .xres = DPY_W,
63 .yres = DPY_H,
64 .xres_virtual = DPY_W,
65 .yres_virtual = DPY_H,
66 .bits_per_pixel = 1,
67 .nonstd = 1,
68 };
69
70 /* main hecubafb functions */
71
apollo_send_data(struct hecubafb_par * par,unsigned char data)72 static void apollo_send_data(struct hecubafb_par *par, unsigned char data)
73 {
74 /* set data */
75 par->board->set_data(par, data);
76
77 /* set DS low */
78 par->board->set_ctl(par, HCB_DS_BIT, 0);
79
80 /* wait for ack */
81 par->board->wait_for_ack(par, 0);
82
83 /* set DS hi */
84 par->board->set_ctl(par, HCB_DS_BIT, 1);
85
86 /* wait for ack to clear */
87 par->board->wait_for_ack(par, 1);
88 }
89
apollo_send_command(struct hecubafb_par * par,unsigned char data)90 static void apollo_send_command(struct hecubafb_par *par, unsigned char data)
91 {
92 /* command so set CD to high */
93 par->board->set_ctl(par, HCB_CD_BIT, 1);
94
95 /* actually strobe with command */
96 apollo_send_data(par, data);
97
98 /* clear CD back to low */
99 par->board->set_ctl(par, HCB_CD_BIT, 0);
100 }
101
hecubafb_dpy_update(struct hecubafb_par * par)102 static void hecubafb_dpy_update(struct hecubafb_par *par)
103 {
104 int i;
105 unsigned char *buf = par->info->screen_buffer;
106
107 apollo_send_command(par, APOLLO_START_NEW_IMG);
108
109 for (i=0; i < (DPY_W*DPY_H/8); i++) {
110 apollo_send_data(par, *(buf++));
111 }
112
113 apollo_send_command(par, APOLLO_STOP_IMG_DATA);
114 apollo_send_command(par, APOLLO_DISPLAY_IMG);
115 }
116
117 /* this is called back from the deferred io workqueue */
hecubafb_dpy_deferred_io(struct fb_info * info,struct list_head * pagereflist)118 static void hecubafb_dpy_deferred_io(struct fb_info *info, struct list_head *pagereflist)
119 {
120 hecubafb_dpy_update(info->par);
121 }
122
hecubafb_defio_damage_range(struct fb_info * info,off_t off,size_t len)123 static void hecubafb_defio_damage_range(struct fb_info *info, off_t off, size_t len)
124 {
125 struct hecubafb_par *par = info->par;
126
127 hecubafb_dpy_update(par);
128 }
129
hecubafb_defio_damage_area(struct fb_info * info,u32 x,u32 y,u32 width,u32 height)130 static void hecubafb_defio_damage_area(struct fb_info *info, u32 x, u32 y,
131 u32 width, u32 height)
132 {
133 struct hecubafb_par *par = info->par;
134
135 hecubafb_dpy_update(par);
136 }
137
138 FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(hecubafb,
139 hecubafb_defio_damage_range,
140 hecubafb_defio_damage_area)
141
142 static const struct fb_ops hecubafb_ops = {
143 .owner = THIS_MODULE,
144 FB_DEFAULT_DEFERRED_OPS(hecubafb),
145 };
146
147 static struct fb_deferred_io hecubafb_defio = {
148 .delay = HZ,
149 .deferred_io = hecubafb_dpy_deferred_io,
150 };
151
hecubafb_probe(struct platform_device * dev)152 static int hecubafb_probe(struct platform_device *dev)
153 {
154 struct fb_info *info;
155 struct hecuba_board *board;
156 int retval = -ENOMEM;
157 int videomemorysize;
158 unsigned char *videomemory;
159 struct hecubafb_par *par;
160
161 /* pick up board specific routines */
162 board = dev->dev.platform_data;
163 if (!board)
164 return -EINVAL;
165
166 /* try to count device specific driver, if can't, platform recalls */
167 if (!try_module_get(board->owner))
168 return -ENODEV;
169
170 videomemorysize = (DPY_W*DPY_H)/8;
171
172 videomemory = vzalloc(videomemorysize);
173 if (!videomemory)
174 goto err_videomem_alloc;
175
176 info = framebuffer_alloc(sizeof(struct hecubafb_par), &dev->dev);
177 if (!info)
178 goto err_fballoc;
179
180 info->screen_buffer = videomemory;
181 info->fbops = &hecubafb_ops;
182
183 info->var = hecubafb_var;
184 info->fix = hecubafb_fix;
185 info->fix.smem_len = videomemorysize;
186 par = info->par;
187 par->info = info;
188 par->board = board;
189 par->send_command = apollo_send_command;
190 par->send_data = apollo_send_data;
191
192 info->flags = FBINFO_VIRTFB;
193
194 info->fbdefio = &hecubafb_defio;
195 fb_deferred_io_init(info);
196
197 retval = register_framebuffer(info);
198 if (retval < 0)
199 goto err_fbreg;
200 platform_set_drvdata(dev, info);
201
202 fb_info(info, "Hecuba frame buffer device, using %dK of video memory\n",
203 videomemorysize >> 10);
204
205 /* this inits the dpy */
206 retval = par->board->init(par);
207 if (retval < 0)
208 goto err_fbreg;
209
210 return 0;
211 err_fbreg:
212 framebuffer_release(info);
213 err_fballoc:
214 vfree(videomemory);
215 err_videomem_alloc:
216 module_put(board->owner);
217 return retval;
218 }
219
hecubafb_remove(struct platform_device * dev)220 static void hecubafb_remove(struct platform_device *dev)
221 {
222 struct fb_info *info = platform_get_drvdata(dev);
223
224 if (info) {
225 struct hecubafb_par *par = info->par;
226 fb_deferred_io_cleanup(info);
227 unregister_framebuffer(info);
228 vfree(info->screen_buffer);
229 if (par->board->remove)
230 par->board->remove(par);
231 module_put(par->board->owner);
232 framebuffer_release(info);
233 }
234 }
235
236 static struct platform_driver hecubafb_driver = {
237 .probe = hecubafb_probe,
238 .remove_new = hecubafb_remove,
239 .driver = {
240 .name = "hecubafb",
241 },
242 };
243 module_platform_driver(hecubafb_driver);
244
245 MODULE_DESCRIPTION("fbdev driver for Hecuba/Apollo controller");
246 MODULE_AUTHOR("Jaya Kumar");
247 MODULE_LICENSE("GPL");
248