2 * linux/drivers/video/hecubafb.c -- FB driver for Hecuba/Apollo controller
4 * Copyright (C) 2006, Jaya Kumar
5 * This work was sponsored by CIS(M) Sdn Bhd
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
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.
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.
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
30 #include <linux/module.h>
31 #include <linux/kernel.h>
32 #include <linux/errno.h>
33 #include <linux/string.h>
35 #include <linux/slab.h>
36 #include <linux/vmalloc.h>
37 #include <linux/delay.h>
38 #include <linux/interrupt.h>
40 #include <linux/init.h>
41 #include <linux/platform_device.h>
42 #include <linux/list.h>
43 #include <linux/uaccess.h>
45 #include <video/hecubafb.h>
47 /* Display specific information */
51 static struct fb_fix_screeninfo hecubafb_fix __devinitdata = {
53 .type = FB_TYPE_PACKED_PIXELS,
54 .visual = FB_VISUAL_MONO01,
59 .accel = FB_ACCEL_NONE,
62 static struct fb_var_screeninfo hecubafb_var __devinitdata = {
65 .xres_virtual = DPY_W,
66 .yres_virtual = DPY_H,
71 /* main hecubafb functions */
73 static void apollo_send_data(struct hecubafb_par *par, unsigned char data)
76 par->board->set_data(par, data);
79 par->board->set_ctl(par, HCB_DS_BIT, 0);
82 par->board->wait_for_ack(par, 0);
85 par->board->set_ctl(par, HCB_DS_BIT, 1);
87 /* wait for ack to clear */
88 par->board->wait_for_ack(par, 1);
91 static void apollo_send_command(struct hecubafb_par *par, unsigned char data)
93 /* command so set CD to high */
94 par->board->set_ctl(par, HCB_CD_BIT, 1);
96 /* actually strobe with command */
97 apollo_send_data(par, data);
99 /* clear CD back to low */
100 par->board->set_ctl(par, HCB_CD_BIT, 0);
103 static void hecubafb_dpy_update(struct hecubafb_par *par)
106 unsigned char *buf = (unsigned char __force *)par->info->screen_base;
108 apollo_send_command(par, APOLLO_START_NEW_IMG);
110 for (i=0; i < (DPY_W*DPY_H/8); i++) {
111 apollo_send_data(par, *(buf++));
114 apollo_send_command(par, APOLLO_STOP_IMG_DATA);
115 apollo_send_command(par, APOLLO_DISPLAY_IMG);
118 /* this is called back from the deferred io workqueue */
119 static void hecubafb_dpy_deferred_io(struct fb_info *info,
120 struct list_head *pagelist)
122 hecubafb_dpy_update(info->par);
125 static void hecubafb_fillrect(struct fb_info *info,
126 const struct fb_fillrect *rect)
128 struct hecubafb_par *par = info->par;
130 sys_fillrect(info, rect);
132 hecubafb_dpy_update(par);
135 static void hecubafb_copyarea(struct fb_info *info,
136 const struct fb_copyarea *area)
138 struct hecubafb_par *par = info->par;
140 sys_copyarea(info, area);
142 hecubafb_dpy_update(par);
145 static void hecubafb_imageblit(struct fb_info *info,
146 const struct fb_image *image)
148 struct hecubafb_par *par = info->par;
150 sys_imageblit(info, image);
152 hecubafb_dpy_update(par);
156 * this is the slow path from userspace. they can seek and write to
157 * the fb. it's inefficient to do anything less than a full screen draw
159 static ssize_t hecubafb_write(struct fb_info *info, const char __user *buf,
160 size_t count, loff_t *ppos)
162 struct hecubafb_par *par = info->par;
163 unsigned long p = *ppos;
166 unsigned long total_size;
168 if (info->state != FBINFO_STATE_RUNNING)
171 total_size = info->fix.smem_len;
176 if (count > total_size) {
181 if (count + p > total_size) {
185 count = total_size - p;
188 dst = (void __force *) (info->screen_base + p);
190 if (copy_from_user(dst, buf, count))
196 hecubafb_dpy_update(par);
198 return (err) ? err : count;
201 static struct fb_ops hecubafb_ops = {
202 .owner = THIS_MODULE,
203 .fb_read = fb_sys_read,
204 .fb_write = hecubafb_write,
205 .fb_fillrect = hecubafb_fillrect,
206 .fb_copyarea = hecubafb_copyarea,
207 .fb_imageblit = hecubafb_imageblit,
210 static struct fb_deferred_io hecubafb_defio = {
212 .deferred_io = hecubafb_dpy_deferred_io,
215 static int __devinit hecubafb_probe(struct platform_device *dev)
217 struct fb_info *info;
218 struct hecuba_board *board;
219 int retval = -ENOMEM;
221 unsigned char *videomemory;
222 struct hecubafb_par *par;
224 /* pick up board specific routines */
225 board = dev->dev.platform_data;
229 /* try to count device specific driver, if can't, platform recalls */
230 if (!try_module_get(board->owner))
233 videomemorysize = (DPY_W*DPY_H)/8;
235 if (!(videomemory = vmalloc(videomemorysize)))
238 memset(videomemory, 0, videomemorysize);
240 info = framebuffer_alloc(sizeof(struct hecubafb_par), &dev->dev);
244 info->screen_base = (char __force __iomem *)videomemory;
245 info->fbops = &hecubafb_ops;
247 info->var = hecubafb_var;
248 info->fix = hecubafb_fix;
249 info->fix.smem_len = videomemorysize;
253 par->send_command = apollo_send_command;
254 par->send_data = apollo_send_data;
256 info->flags = FBINFO_FLAG_DEFAULT;
258 info->fbdefio = &hecubafb_defio;
259 fb_deferred_io_init(info);
261 retval = register_framebuffer(info);
264 platform_set_drvdata(dev, info);
267 "fb%d: Hecuba frame buffer device, using %dK of video memory\n",
268 info->node, videomemorysize >> 10);
270 /* this inits the dpy */
271 retval = par->board->init(par);
277 framebuffer_release(info);
280 module_put(board->owner);
284 static int __devexit hecubafb_remove(struct platform_device *dev)
286 struct fb_info *info = platform_get_drvdata(dev);
289 struct hecubafb_par *par = info->par;
290 fb_deferred_io_cleanup(info);
291 unregister_framebuffer(info);
292 vfree((void __force *)info->screen_base);
293 if (par->board->remove)
294 par->board->remove(par);
295 module_put(par->board->owner);
296 framebuffer_release(info);
301 static struct platform_driver hecubafb_driver = {
302 .probe = hecubafb_probe,
303 .remove = hecubafb_remove,
305 .owner = THIS_MODULE,
310 static int __init hecubafb_init(void)
312 return platform_driver_register(&hecubafb_driver);
315 static void __exit hecubafb_exit(void)
317 platform_driver_unregister(&hecubafb_driver);
320 module_init(hecubafb_init);
321 module_exit(hecubafb_exit);
323 MODULE_DESCRIPTION("fbdev driver for Hecuba/Apollo controller");
324 MODULE_AUTHOR("Jaya Kumar");
325 MODULE_LICENSE("GPL");