tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * linux/drivers/video/clps711xfb.c
3 *
4 * Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 * Framebuffer driver for the CLPS7111 and EP7212 processors.
21 */
22#include <linux/module.h>
23#include <linux/kernel.h>
24#include <linux/slab.h>
25#include <linux/fb.h>
26#include <linux/init.h>
27#include <linux/proc_fs.h>
28#include <linux/delay.h>
29
30#include <mach/hardware.h>
31#include <asm/mach-types.h>
32#include <linux/uaccess.h>
33
34#include <asm/hardware/clps7111.h>
35#include <mach/syspld.h>
36
37struct fb_info *cfb;
38
39#define CMAP_MAX_SIZE 16
40
41/* The /proc entry for the backlight. */
42static struct proc_dir_entry *clps7111fb_backlight_proc_entry = NULL;
43
44static int clps7111fb_proc_backlight_read(char *page, char **start, off_t off,
45 int count, int *eof, void *data);
46static int clps7111fb_proc_backlight_write(struct file *file,
47 const char *buffer, unsigned long count, void *data);
48
49/*
50 * LCD AC Prescale. This comes from the LCD panel manufacturers specifications.
51 * This determines how many clocks + 1 of CL1 before the M signal toggles.
52 * The number of lines on the display must not be divisible by this number.
53 */
54static unsigned int lcd_ac_prescale = 13;
55
56/*
57 * Set a single color register. Return != 0 for invalid regno.
58 */
59static int
60clps7111fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
61 u_int transp, struct fb_info *info)
62{
63 unsigned int level, mask, shift, pal;
64
65 if (regno >= (1 << info->var.bits_per_pixel))
66 return 1;
67
68 /* gray = 0.30*R + 0.58*G + 0.11*B */
69 level = (red * 77 + green * 151 + blue * 28) >> 20;
70
71 /*
72 * On an LCD, a high value is dark, while a low value is light.
73 * So we invert the level.
74 *
75 * This isn't true on all machines, so we only do it on EDB7211.
76 * --rmk
77 */
78 if (machine_is_edb7211()) {
79 level = 15 - level;
80 }
81
82 shift = 4 * (regno & 7);
83 level <<= shift;
84 mask = 15 << shift;
85 level &= mask;
86
87 regno = regno < 8 ? PALLSW : PALMSW;
88
89 pal = clps_readl(regno);
90 pal = (pal & ~mask) | level;
91 clps_writel(pal, regno);
92
93 return 0;
94}
95
96/*
97 * Validate the purposed mode.
98 */
99static int
100clps7111fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
101{
102 var->transp.msb_right = 0;
103 var->transp.offset = 0;
104 var->transp.length = 0;
105 var->red.msb_right = 0;
106 var->red.offset = 0;
107 var->red.length = var->bits_per_pixel;
108 var->green = var->red;
109 var->blue = var->red;
110
111 if (var->bits_per_pixel > 4)
112 return -EINVAL;
113
114 return 0;
115}
116
117/*
118 * Set the hardware state.
119 */
120static int
121clps7111fb_set_par(struct fb_info *info)
122{
123 unsigned int lcdcon, syscon, pixclock;
124
125 switch (info->var.bits_per_pixel) {
126 case 1:
127 info->fix.visual = FB_VISUAL_MONO01;
128 break;
129 case 2:
130 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
131 break;
132 case 4:
133 info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
134 break;
135 }
136
137 info->fix.line_length = info->var.xres_virtual * info->var.bits_per_pixel / 8;
138
139 lcdcon = (info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel) / 128 - 1;
140 lcdcon |= ((info->var.xres_virtual / 16) - 1) << 13;
141 lcdcon |= lcd_ac_prescale << 25;
142
143 /*
144 * Calculate pixel prescale value from the pixclock. This is:
145 * 36.864MHz / pixclock_mhz - 1.
146 * However, pixclock is in picoseconds, so this ends up being:
147 * 36864000 * pixclock_ps / 10^12 - 1
148 * and this will overflow the 32-bit math. We perform this as
149 * (9 * 4096000 == 36864000):
150 * pixclock_ps * 9 * (4096000 / 10^12) - 1
151 */
152 pixclock = 9 * info->var.pixclock / 244140 - 1;
153 lcdcon |= pixclock << 19;
154
155 if (info->var.bits_per_pixel == 4)
156 lcdcon |= LCDCON_GSMD;
157 if (info->var.bits_per_pixel >= 2)
158 lcdcon |= LCDCON_GSEN;
159
160 /*
161 * LCDCON must only be changed while the LCD is disabled
162 */
163 syscon = clps_readl(SYSCON1);
164 clps_writel(syscon & ~SYSCON1_LCDEN, SYSCON1);
165 clps_writel(lcdcon, LCDCON);
166 clps_writel(syscon | SYSCON1_LCDEN, SYSCON1);
167 return 0;
168}
169
170static int clps7111fb_blank(int blank, struct fb_info *info)
171{
172 if (blank) {
173 if (machine_is_edb7211()) {
174 /* Turn off the LCD backlight. */
175 clps_writeb(clps_readb(PDDR) & ~EDB_PD3_LCDBL, PDDR);
176
177 /* Power off the LCD DC-DC converter. */
178 clps_writeb(clps_readb(PDDR) & ~EDB_PD1_LCD_DC_DC_EN, PDDR);
179
180 /* Delay for a little while (half a second). */
181 udelay(100);
182
183 /* Power off the LCD panel. */
184 clps_writeb(clps_readb(PDDR) & ~EDB_PD2_LCDEN, PDDR);
185
186 /* Power off the LCD controller. */
187 clps_writel(clps_readl(SYSCON1) & ~SYSCON1_LCDEN,
188 SYSCON1);
189 }
190 } else {
191 if (machine_is_edb7211()) {
192 /* Power up the LCD controller. */
193 clps_writel(clps_readl(SYSCON1) | SYSCON1_LCDEN,
194 SYSCON1);
195
196 /* Power up the LCD panel. */
197 clps_writeb(clps_readb(PDDR) | EDB_PD2_LCDEN, PDDR);
198
199 /* Delay for a little while. */
200 udelay(100);
201
202 /* Power up the LCD DC-DC converter. */
203 clps_writeb(clps_readb(PDDR) | EDB_PD1_LCD_DC_DC_EN,
204 PDDR);
205
206 /* Turn on the LCD backlight. */
207 clps_writeb(clps_readb(PDDR) | EDB_PD3_LCDBL, PDDR);
208 }
209 }
210 return 0;
211}
212
213static struct fb_ops clps7111fb_ops = {
214 .owner = THIS_MODULE,
215 .fb_check_var = clps7111fb_check_var,
216 .fb_set_par = clps7111fb_set_par,
217 .fb_setcolreg = clps7111fb_setcolreg,
218 .fb_blank = clps7111fb_blank,
219 .fb_fillrect = cfb_fillrect,
220 .fb_copyarea = cfb_copyarea,
221 .fb_imageblit = cfb_imageblit,
222};
223
224static int
225clps7111fb_proc_backlight_read(char *page, char **start, off_t off,
226 int count, int *eof, void *data)
227{
228 /* We need at least two characters, one for the digit, and one for
229 * the terminating NULL. */
230 if (count < 2)
231 return -EINVAL;
232
233 if (machine_is_edb7211()) {
234 return sprintf(page, "%d\n",
235 (clps_readb(PDDR) & EDB_PD3_LCDBL) ? 1 : 0);
236 }
237
238 return 0;
239}
240
241static int
242clps7111fb_proc_backlight_write(struct file *file, const char *buffer,
243 unsigned long count, void *data)
244{
245 unsigned char char_value;
246 int value;
247
248 if (count < 1) {
249 return -EINVAL;
250 }
251
252 if (copy_from_user(&char_value, buffer, 1))
253 return -EFAULT;
254
255 value = char_value - '0';
256
257 if (machine_is_edb7211()) {
258 unsigned char port_d;
259
260 port_d = clps_readb(PDDR);
261
262 if (value) {
263 port_d |= EDB_PD3_LCDBL;
264 } else {
265 port_d &= ~EDB_PD3_LCDBL;
266 }
267
268 clps_writeb(port_d, PDDR);
269 }
270
271 return count;
272}
273
274static void __init clps711x_guess_lcd_params(struct fb_info *info)
275{
276 unsigned int lcdcon, syscon, size;
277 unsigned long phys_base = PAGE_OFFSET;
278 void *virt_base = (void *)PAGE_OFFSET;
279
280 info->var.xres_virtual = 640;
281 info->var.yres_virtual = 240;
282 info->var.bits_per_pixel = 4;
283 info->var.activate = FB_ACTIVATE_NOW;
284 info->var.height = -1;
285 info->var.width = -1;
286 info->var.pixclock = 93006; /* 10.752MHz pixel clock */
287
288 /*
289 * If the LCD controller is already running, decode the values
290 * in LCDCON to xres/yres/bpp/pixclock/acprescale
291 */
292 syscon = clps_readl(SYSCON1);
293 if (syscon & SYSCON1_LCDEN) {
294 lcdcon = clps_readl(LCDCON);
295
296 /*
297 * Decode GSMD and GSEN bits to bits per pixel
298 */
299 switch (lcdcon & (LCDCON_GSMD | LCDCON_GSEN)) {
300 case LCDCON_GSMD | LCDCON_GSEN:
301 info->var.bits_per_pixel = 4;
302 break;
303
304 case LCDCON_GSEN:
305 info->var.bits_per_pixel = 2;
306 break;
307
308 default:
309 info->var.bits_per_pixel = 1;
310 break;
311 }
312
313 /*
314 * Decode xres/yres
315 */
316 info->var.xres_virtual = (((lcdcon >> 13) & 0x3f) + 1) * 16;
317 info->var.yres_virtual = (((lcdcon & 0x1fff) + 1) * 128) /
318 (info->var.xres_virtual *
319 info->var.bits_per_pixel);
320
321 /*
322 * Calculate pixclock
323 */
324 info->var.pixclock = (((lcdcon >> 19) & 0x3f) + 1) * 244140 / 9;
325
326 /*
327 * Grab AC prescale
328 */
329 lcd_ac_prescale = (lcdcon >> 25) & 0x1f;
330 }
331
332 info->var.xres = info->var.xres_virtual;
333 info->var.yres = info->var.yres_virtual;
334 info->var.grayscale = info->var.bits_per_pixel > 1;
335
336 size = info->var.xres * info->var.yres * info->var.bits_per_pixel / 8;
337
338 /*
339 * Might be worth checking to see if we can use the on-board
340 * RAM if size here...
341 * CLPS7110 - no on-board SRAM
342 * EP7212 - 38400 bytes
343 */
344 if (size <= 38400) {
345 printk(KERN_INFO "CLPS711xFB: could use on-board SRAM?\n");
346 }
347
348 if ((syscon & SYSCON1_LCDEN) == 0) {
349 /*
350 * The display isn't running. Ensure that
351 * the display memory is empty.
352 */
353 memset(virt_base, 0, size);
354 }
355
356 info->screen_base = virt_base;
357 info->fix.smem_start = phys_base;
358 info->fix.smem_len = PAGE_ALIGN(size);
359 info->fix.type = FB_TYPE_PACKED_PIXELS;
360}
361
362int __init clps711xfb_init(void)
363{
364 int err = -ENOMEM;
365
366 if (fb_get_options("clps711xfb", NULL))
367 return -ENODEV;
368
369 cfb = kzalloc(sizeof(*cfb), GFP_KERNEL);
370 if (!cfb)
371 goto out;
372
373 strcpy(cfb->fix.id, "clps711x");
374
375 cfb->fbops = &clps7111fb_ops;
376 cfb->flags = FBINFO_DEFAULT;
377
378 clps711x_guess_lcd_params(cfb);
379
380 fb_alloc_cmap(&cfb->cmap, CMAP_MAX_SIZE, 0);
381
382 /* Register the /proc entries. */
383 clps7111fb_backlight_proc_entry = create_proc_entry("backlight", 0444,
384 NULL);
385 if (clps7111fb_backlight_proc_entry == NULL) {
386 printk("Couldn't create the /proc entry for the backlight.\n");
387 return -EINVAL;
388 }
389
390 clps7111fb_backlight_proc_entry->read_proc =
391 &clps7111fb_proc_backlight_read;
392 clps7111fb_backlight_proc_entry->write_proc =
393 &clps7111fb_proc_backlight_write;
394
395 /*
396 * Power up the LCD
397 */
398 if (machine_is_p720t()) {
399 PLD_LCDEN = PLD_LCDEN_EN;
400 PLD_PWR |= (PLD_S4_ON|PLD_S3_ON|PLD_S2_ON|PLD_S1_ON);
401 }
402
403 if (machine_is_edb7211()) {
404 /* Power up the LCD panel. */
405 clps_writeb(clps_readb(PDDR) | EDB_PD2_LCDEN, PDDR);
406
407 /* Delay for a little while. */
408 udelay(100);
409
410 /* Power up the LCD DC-DC converter. */
411 clps_writeb(clps_readb(PDDR) | EDB_PD1_LCD_DC_DC_EN, PDDR);
412
413 /* Turn on the LCD backlight. */
414 clps_writeb(clps_readb(PDDR) | EDB_PD3_LCDBL, PDDR);
415 }
416
417 err = register_framebuffer(cfb);
418
419out: return err;
420}
421
422static void __exit clps711xfb_exit(void)
423{
424 unregister_framebuffer(cfb);
425 kfree(cfb);
426
427 /*
428 * Power down the LCD
429 */
430 if (machine_is_p720t()) {
431 PLD_LCDEN = 0;
432 PLD_PWR &= ~(PLD_S4_ON|PLD_S3_ON|PLD_S2_ON|PLD_S1_ON);
433 }
434}
435
436module_init(clps711xfb_init);
437module_exit(clps711xfb_exit);
438
439MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
440MODULE_DESCRIPTION("CLPS711x framebuffer driver");
441MODULE_LICENSE("GPL");