Merge branch 'linus' into x86/tracehook
[linux-2.6] / drivers / video / cobalt_lcdfb.c
1 /*
2  *  Cobalt server LCD frame buffer driver.
3  *
4  *  Copyright (C) 2008  Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 #include <linux/delay.h>
21 #include <linux/fb.h>
22 #include <linux/init.h>
23 #include <linux/io.h>
24 #include <linux/ioport.h>
25 #include <linux/uaccess.h>
26 #include <linux/platform_device.h>
27
28 /*
29  * Cursor position address
30  * \X  0    1    2  ...  14   15
31  * Y+----+----+----+---+----+----+
32  * 0|0x00|0x01|0x02|...|0x0e|0x0f|
33  *  +----+----+----+---+----+----+
34  * 1|0x40|0x41|0x42|...|0x4e|0x4f|
35  *  +----+----+----+---+----+----+
36  */
37 #define LCD_DATA_REG_OFFSET     0x10
38 #define LCD_XRES_MAX            16
39 #define LCD_YRES_MAX            2
40 #define LCD_CHARS_MAX           32
41
42 #define LCD_CLEAR               0x01
43 #define LCD_CURSOR_MOVE_HOME    0x02
44 #define LCD_RESET               0x06
45 #define LCD_OFF                 0x08
46 #define LCD_CURSOR_OFF          0x0c
47 #define LCD_CURSOR_BLINK_OFF    0x0e
48 #define LCD_CURSOR_ON           0x0f
49 #define LCD_ON                  LCD_CURSOR_ON
50 #define LCD_CURSOR_MOVE_LEFT    0x10
51 #define LCD_CURSOR_MOVE_RIGHT   0x14
52 #define LCD_DISPLAY_LEFT        0x18
53 #define LCD_DISPLAY_RIGHT       0x1c
54 #define LCD_PRERESET            0x3f    /* execute 4 times continuously */
55 #define LCD_BUSY                0x80
56
57 #define LCD_GRAPHIC_MODE        0x40
58 #define LCD_TEXT_MODE           0x80
59 #define LCD_CUR_POS_MASK        0x7f
60
61 #define LCD_CUR_POS(x)          ((x) & LCD_CUR_POS_MASK)
62 #define LCD_TEXT_POS(x)         ((x) | LCD_TEXT_MODE)
63
64 static inline void lcd_write_control(struct fb_info *info, u8 control)
65 {
66         writel((u32)control << 24, info->screen_base);
67 }
68
69 static inline u8 lcd_read_control(struct fb_info *info)
70 {
71         return readl(info->screen_base) >> 24;
72 }
73
74 static inline void lcd_write_data(struct fb_info *info, u8 data)
75 {
76         writel((u32)data << 24, info->screen_base + LCD_DATA_REG_OFFSET);
77 }
78
79 static inline u8 lcd_read_data(struct fb_info *info)
80 {
81         return readl(info->screen_base + LCD_DATA_REG_OFFSET) >> 24;
82 }
83
84 static int lcd_busy_wait(struct fb_info *info)
85 {
86         u8 val = 0;
87         int timeout = 10, retval = 0;
88
89         do {
90                 val = lcd_read_control(info);
91                 val &= LCD_BUSY;
92                 if (val != LCD_BUSY)
93                         break;
94
95                 if (msleep_interruptible(1))
96                         return -EINTR;
97
98                 timeout--;
99         } while (timeout);
100
101         if (val == LCD_BUSY)
102                 retval = -EBUSY;
103
104         return retval;
105 }
106
107 static void lcd_clear(struct fb_info *info)
108 {
109         int i;
110
111         for (i = 0; i < 4; i++) {
112                 udelay(150);
113
114                 lcd_write_control(info, LCD_PRERESET);
115         }
116
117         udelay(150);
118
119         lcd_write_control(info, LCD_CLEAR);
120
121         udelay(150);
122
123         lcd_write_control(info, LCD_RESET);
124 }
125
126 static struct fb_fix_screeninfo cobalt_lcdfb_fix __initdata = {
127         .id             = "cobalt-lcd",
128         .type           = FB_TYPE_TEXT,
129         .type_aux       = FB_AUX_TEXT_MDA,
130         .visual         = FB_VISUAL_MONO01,
131         .line_length    = LCD_XRES_MAX,
132         .accel          = FB_ACCEL_NONE,
133 };
134
135 static ssize_t cobalt_lcdfb_read(struct fb_info *info, char __user *buf,
136                                  size_t count, loff_t *ppos)
137 {
138         char src[LCD_CHARS_MAX];
139         unsigned long pos;
140         int len, retval = 0;
141
142         pos = *ppos;
143         if (pos >= LCD_CHARS_MAX || count == 0)
144                 return 0;
145
146         if (count > LCD_CHARS_MAX)
147                 count = LCD_CHARS_MAX;
148
149         if (pos + count > LCD_CHARS_MAX)
150                 count = LCD_CHARS_MAX - pos;
151
152         for (len = 0; len < count; len++) {
153                 retval = lcd_busy_wait(info);
154                 if (retval < 0)
155                         break;
156
157                 lcd_write_control(info, LCD_TEXT_POS(pos));
158
159                 retval = lcd_busy_wait(info);
160                 if (retval < 0)
161                         break;
162
163                 src[len] = lcd_read_data(info);
164                 if (pos == 0x0f)
165                         pos = 0x40;
166                 else
167                         pos++;
168         }
169
170         if (retval < 0 && signal_pending(current))
171                 return -ERESTARTSYS;
172
173         if (copy_to_user(buf, src, len))
174                 return -EFAULT;
175
176         *ppos += len;
177
178         return len;
179 }
180
181 static ssize_t cobalt_lcdfb_write(struct fb_info *info, const char __user *buf,
182                                   size_t count, loff_t *ppos)
183 {
184         char dst[LCD_CHARS_MAX];
185         unsigned long pos;
186         int len, retval = 0;
187
188         pos = *ppos;
189         if (pos >= LCD_CHARS_MAX || count == 0)
190                 return 0;
191
192         if (count > LCD_CHARS_MAX)
193                 count = LCD_CHARS_MAX;
194
195         if (pos + count > LCD_CHARS_MAX)
196                 count = LCD_CHARS_MAX - pos;
197
198         if (copy_from_user(dst, buf, count))
199                 return -EFAULT;
200
201         for (len = 0; len < count; len++) {
202                 retval = lcd_busy_wait(info);
203                 if (retval < 0)
204                         break;
205
206                 lcd_write_control(info, LCD_TEXT_POS(pos));
207
208                 retval = lcd_busy_wait(info);
209                 if (retval < 0)
210                         break;
211
212                 lcd_write_data(info, dst[len]);
213                 if (pos == 0x0f)
214                         pos = 0x40;
215                 else
216                         pos++;
217         }
218
219         if (retval < 0 && signal_pending(current))
220                 return -ERESTARTSYS;
221
222         *ppos += len;
223
224         return len;
225 }
226
227 static int cobalt_lcdfb_blank(int blank_mode, struct fb_info *info)
228 {
229         int retval;
230
231         retval = lcd_busy_wait(info);
232         if (retval < 0)
233                 return retval;
234
235         switch (blank_mode) {
236         case FB_BLANK_UNBLANK:
237                 lcd_write_control(info, LCD_ON);
238                 break;
239         default:
240                 lcd_write_control(info, LCD_OFF);
241                 break;
242         }
243
244         return 0;
245 }
246
247 static int cobalt_lcdfb_cursor(struct fb_info *info, struct fb_cursor *cursor)
248 {
249         u32 x, y;
250         int retval;
251
252         switch (cursor->set) {
253         case FB_CUR_SETPOS:
254                 x = cursor->image.dx;
255                 y = cursor->image.dy;
256                 if (x >= LCD_XRES_MAX || y >= LCD_YRES_MAX)
257                         return -EINVAL;
258
259                 retval = lcd_busy_wait(info);
260                 if (retval < 0)
261                         return retval;
262
263                 lcd_write_control(info,
264                                   LCD_TEXT_POS(info->fix.line_length * y + x));
265                 break;
266         default:
267                 return -EINVAL;
268         }
269
270         retval = lcd_busy_wait(info);
271         if (retval < 0)
272                 return retval;
273
274         if (cursor->enable)
275                 lcd_write_control(info, LCD_CURSOR_ON);
276         else
277                 lcd_write_control(info, LCD_CURSOR_OFF);
278
279         return 0;
280 }
281
282 static struct fb_ops cobalt_lcd_fbops = {
283         .owner          = THIS_MODULE,
284         .fb_read        = cobalt_lcdfb_read,
285         .fb_write       = cobalt_lcdfb_write,
286         .fb_blank       = cobalt_lcdfb_blank,
287         .fb_cursor      = cobalt_lcdfb_cursor,
288 };
289
290 static int __init cobalt_lcdfb_probe(struct platform_device *dev)
291 {
292         struct fb_info *info;
293         struct resource *res;
294         int retval;
295
296         info = framebuffer_alloc(0, &dev->dev);
297         if (!info)
298                 return -ENOMEM;
299
300         res = platform_get_resource(dev, IORESOURCE_MEM, 0);
301         if (!res) {
302                 framebuffer_release(info);
303                 return -EBUSY;
304         }
305
306         info->screen_size = res->end - res->start + 1;
307         info->screen_base = ioremap(res->start, info->screen_size);
308         info->fbops = &cobalt_lcd_fbops;
309         info->fix = cobalt_lcdfb_fix;
310         info->fix.smem_start = res->start;
311         info->fix.smem_len = info->screen_size;
312         info->pseudo_palette = NULL;
313         info->par = NULL;
314         info->flags = FBINFO_DEFAULT;
315
316         retval = register_framebuffer(info);
317         if (retval < 0) {
318                 iounmap(info->screen_base);
319                 framebuffer_release(info);
320                 return retval;
321         }
322
323         platform_set_drvdata(dev, info);
324
325         lcd_clear(info);
326
327         printk(KERN_INFO "fb%d: Cobalt server LCD frame buffer device\n",
328                 info->node);
329
330         return 0;
331 }
332
333 static int __devexit cobalt_lcdfb_remove(struct platform_device *dev)
334 {
335         struct fb_info *info;
336
337         info = platform_get_drvdata(dev);
338         if (info) {
339                 iounmap(info->screen_base);
340                 unregister_framebuffer(info);
341                 framebuffer_release(info);
342         }
343
344         return 0;
345 }
346
347 static struct platform_driver cobalt_lcdfb_driver = {
348         .probe  = cobalt_lcdfb_probe,
349         .remove = __devexit_p(cobalt_lcdfb_remove),
350         .driver = {
351                 .name   = "cobalt-lcd",
352                 .owner  = THIS_MODULE,
353         },
354 };
355
356 static int __init cobalt_lcdfb_init(void)
357 {
358         return platform_driver_register(&cobalt_lcdfb_driver);
359 }
360
361 static void __exit cobalt_lcdfb_exit(void)
362 {
363         platform_driver_unregister(&cobalt_lcdfb_driver);
364 }
365
366 module_init(cobalt_lcdfb_init);
367 module_exit(cobalt_lcdfb_exit);
368
369 MODULE_LICENSE("GPL v2");
370 MODULE_AUTHOR("Yoichi Yuasa");
371 MODULE_DESCRIPTION("Cobalt server LCD frame buffer driver");