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 | |
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 | |
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 | |
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, data: *(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 */ |
118 | static void hecubafb_dpy_deferred_io(struct fb_info *info, struct list_head *) |
119 | { |
120 | hecubafb_dpy_update(par: info->par); |
121 | } |
122 | |
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 | |
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 | |
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(module: board->owner)) |
168 | return -ENODEV; |
169 | |
170 | videomemorysize = (DPY_W*DPY_H)/8; |
171 | |
172 | videomemory = vzalloc(size: videomemorysize); |
173 | if (!videomemory) |
174 | goto err_videomem_alloc; |
175 | |
176 | info = framebuffer_alloc(size: sizeof(struct hecubafb_par), dev: &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(fb_info: info); |
198 | if (retval < 0) |
199 | goto err_fbreg; |
200 | platform_set_drvdata(pdev: dev, data: 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(addr: videomemory); |
215 | err_videomem_alloc: |
216 | module_put(module: board->owner); |
217 | return retval; |
218 | } |
219 | |
220 | static void hecubafb_remove(struct platform_device *dev) |
221 | { |
222 | struct fb_info *info = platform_get_drvdata(pdev: dev); |
223 | |
224 | if (info) { |
225 | struct hecubafb_par *par = info->par; |
226 | fb_deferred_io_cleanup(info); |
227 | unregister_framebuffer(fb_info: info); |
228 | vfree(addr: info->screen_buffer); |
229 | if (par->board->remove) |
230 | par->board->remove(par); |
231 | module_put(module: 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 | |