2 * linux/drivers/video/arcfb.c -- FB driver for Arc monochrome LCD board
4 * Copyright (C) 2005, Jaya Kumar <jayalk@intworks.biz>
5 * http://www.intworks.biz/arclcd
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.
13 * This driver was written to be used with the Arc LCD board. Arc uses a
14 * set of KS108 chips that control individual 64x64 LCD matrices. The board
15 * can be paneled in a variety of setups such as 2x1=128x64, 4x4=256x256 and
16 * so on. The interface between the board and the host is TTL based GPIO. The
17 * GPIO requirements are 8 writable data lines and 4+n lines for control. On a
18 * GPIO-less system, the board can be tested by connecting the respective sigs
19 * up to a parallel port connector. The driver requires the IO addresses for
20 * data and control GPIO at load time. It is unable to probe for the
21 * existence of the LCD so it must be told at load time whether it should
26 * - testing with interrupt hw
29 * - User must set tuhold. It's in microseconds. According to the 108 spec,
30 * the hold time is supposed to be at least 1 microsecond.
31 * - User must set num_cols=x num_rows=y, eg: x=2 means 128
32 * - User must set arcfb_enable=1 to enable it
33 * - User must set dio_addr=0xIOADDR cio_addr=0xIOADDR
37 #include <linux/module.h>
38 #include <linux/kernel.h>
39 #include <linux/errno.h>
40 #include <linux/string.h>
42 #include <linux/vmalloc.h>
43 #include <linux/delay.h>
44 #include <linux/interrupt.h>
46 #include <linux/init.h>
47 #include <linux/arcfb.h>
48 #include <linux/platform_device.h>
50 #include <linux/uaccess.h>
52 #define floor8(a) (a&(~0x07))
53 #define floorXres(a,xres) (a&(~(xres - 1)))
54 #define iceil8(a) (((int)((a+7)/8))*8)
55 #define ceil64(a) (a|0x3F)
56 #define ceilXres(a,xres) (a|(xres - 1))
58 /* ks108 chipset specific defines and code */
60 #define KS_SET_DPY_START_LINE 0xC0
61 #define KS_SET_PAGE_NUM 0xB8
65 #define KS_SEL_CMD 0x08
66 #define KS_SEL_DATA 0x00
67 #define KS_DPY_ON 0x3F
68 #define KS_DPY_OFF 0x3E
69 #define KS_INTACK 0x40
70 #define KS_CLRINT 0x02
73 unsigned long dio_addr;
74 unsigned long cio_addr;
75 unsigned long c2io_addr;
77 unsigned char cslut[9];
83 static struct fb_fix_screeninfo arcfb_fix __devinitdata = {
85 .type = FB_TYPE_PACKED_PIXELS,
86 .visual = FB_VISUAL_MONO01,
90 .accel = FB_ACCEL_NONE,
93 static struct fb_var_screeninfo arcfb_var __devinitdata = {
102 static unsigned long num_cols;
103 static unsigned long num_rows;
104 static unsigned long dio_addr;
105 static unsigned long cio_addr;
106 static unsigned long c2io_addr;
107 static unsigned long splashval;
108 static unsigned long tuhold;
109 static unsigned int nosplash;
110 static unsigned int arcfb_enable;
111 static unsigned int irq;
113 static DECLARE_WAIT_QUEUE_HEAD(arcfb_waitq);
115 static void ks108_writeb_ctl(struct arcfb_par *par,
116 unsigned int chipindex, unsigned char value)
118 unsigned char chipselval = par->cslut[chipindex];
120 outb(chipselval|KS_CEHI|KS_SEL_CMD, par->cio_addr);
121 outb(value, par->dio_addr);
123 outb(chipselval|KS_CELO|KS_SEL_CMD, par->cio_addr);
126 static void ks108_writeb_mainctl(struct arcfb_par *par, unsigned char value)
129 outb(value, par->cio_addr);
133 static unsigned char ks108_readb_ctl2(struct arcfb_par *par)
135 return inb(par->c2io_addr);
138 static void ks108_writeb_data(struct arcfb_par *par,
139 unsigned int chipindex, unsigned char value)
141 unsigned char chipselval = par->cslut[chipindex];
143 outb(chipselval|KS_CEHI|KS_SEL_DATA, par->cio_addr);
144 outb(value, par->dio_addr);
146 outb(chipselval|KS_CELO|KS_SEL_DATA, par->cio_addr);
149 static void ks108_set_start_line(struct arcfb_par *par,
150 unsigned int chipindex, unsigned char y)
152 ks108_writeb_ctl(par, chipindex, KS_SET_DPY_START_LINE|y);
155 static void ks108_set_yaddr(struct arcfb_par *par,
156 unsigned int chipindex, unsigned char y)
158 ks108_writeb_ctl(par, chipindex, KS_SET_PAGE_NUM|y);
161 static void ks108_set_xaddr(struct arcfb_par *par,
162 unsigned int chipindex, unsigned char x)
164 ks108_writeb_ctl(par, chipindex, KS_SET_X|x);
167 static void ks108_clear_lcd(struct arcfb_par *par, unsigned int chipindex)
171 for (i = 0; i <= 8; i++) {
172 ks108_set_yaddr(par, chipindex, i);
173 ks108_set_xaddr(par, chipindex, 0);
174 for (j = 0; j < 64; j++) {
175 ks108_writeb_data(par, chipindex,
176 (unsigned char) splashval);
181 /* main arcfb functions */
183 static int arcfb_open(struct fb_info *info, int user)
185 struct arcfb_par *par = info->par;
187 atomic_inc(&par->ref_count);
191 static int arcfb_release(struct fb_info *info, int user)
193 struct arcfb_par *par = info->par;
194 int count = atomic_read(&par->ref_count);
198 atomic_dec(&par->ref_count);
202 static int arcfb_pan_display(struct fb_var_screeninfo *var,
203 struct fb_info *info)
206 struct arcfb_par *par = info->par;
208 if ((var->vmode & FB_VMODE_YWRAP) && (var->yoffset < 64)
209 && (info->var.yres <= 64)) {
210 for (i = 0; i < num_cols; i++) {
211 ks108_set_start_line(par, i, var->yoffset);
213 info->var.yoffset = var->yoffset;
220 static irqreturn_t arcfb_interrupt(int vec, void *dev_instance)
222 struct fb_info *info = dev_instance;
223 unsigned char ctl2status;
224 struct arcfb_par *par = info->par;
226 ctl2status = ks108_readb_ctl2(par);
228 if (!(ctl2status & KS_INTACK)) /* not arc generated interrupt */
231 ks108_writeb_mainctl(par, KS_CLRINT);
233 spin_lock(&par->lock);
234 if (waitqueue_active(&arcfb_waitq)) {
235 wake_up(&arcfb_waitq);
237 spin_unlock(&par->lock);
243 * here we handle a specific page on the lcd. the complexity comes from
244 * the fact that the fb is laidout in 8xX vertical columns. we extract
245 * each write of 8 vertical pixels. then we shift out as we move along
246 * X. That's what rightshift does. bitmask selects the desired input bit.
248 static void arcfb_lcd_update_page(struct arcfb_par *par, unsigned int upper,
249 unsigned int left, unsigned int right, unsigned int distance)
252 unsigned int xindex, yindex, chipindex, linesize;
255 unsigned char bitmask, rightshift;
259 chipindex = (xindex + (yindex*num_cols));
261 ks108_set_yaddr(par, chipindex, upper/8);
263 linesize = par->info->var.xres/8;
264 src = (unsigned char __force *) par->info->screen_base + (left/8) +
266 ks108_set_xaddr(par, chipindex, left);
270 while (left <= right) {
272 for (i = 0; i < 8; i++) {
273 if ( i > rightshift) {
274 val |= (*(src + (i*linesize)) & bitmask)
277 val |= (*(src + (i*linesize)) & bitmask)
281 ks108_writeb_data(par, chipindex, val);
283 if (bitmask == 0x80) {
295 * here we handle the entire vertical page of the update. we write across
296 * lcd chips. update_page uses the upper/left values to decide which
297 * chip to select for the right. upper is needed for setting the page
298 * desired for the write.
300 static void arcfb_lcd_update_vert(struct arcfb_par *par, unsigned int top,
301 unsigned int bottom, unsigned int left, unsigned int right)
303 unsigned int distance, upper, lower;
305 distance = (bottom - top) + 1;
309 while (distance > 0) {
311 arcfb_lcd_update_page(par, upper, left, right, 8);
318 * here we handle horizontal blocks for the update. update_vert will
319 * handle spaning multiple pages. we break out each horizontal
320 * block in to individual blocks no taller than 64 pixels.
322 static void arcfb_lcd_update_horiz(struct arcfb_par *par, unsigned int left,
323 unsigned int right, unsigned int top, unsigned int h)
325 unsigned int distance, upper, lower;
329 lower = min(upper + distance - 1, ceil64(upper));
331 while (distance > 0) {
332 distance -= ((lower - upper) + 1 );
333 arcfb_lcd_update_vert(par, upper, lower, left, right);
335 lower = min(upper + distance - 1, ceil64(upper));
340 * here we start the process of spliting out the fb update into
341 * individual blocks of pixels. we end up spliting into 64x64 blocks
342 * and finally down to 64x8 pages.
344 static void arcfb_lcd_update(struct arcfb_par *par, unsigned int dx,
345 unsigned int dy, unsigned int w, unsigned int h)
347 unsigned int left, right, distance, y;
349 /* align the request first */
356 right = min(left + w - 1, ceil64(left));
358 while (distance > 0) {
359 arcfb_lcd_update_horiz(par, left, right, y, h);
360 distance -= ((right - left) + 1);
362 right = min(left + distance - 1, ceil64(left));
366 static void arcfb_fillrect(struct fb_info *info,
367 const struct fb_fillrect *rect)
369 struct arcfb_par *par = info->par;
371 sys_fillrect(info, rect);
373 /* update the physical lcd */
374 arcfb_lcd_update(par, rect->dx, rect->dy, rect->width, rect->height);
377 static void arcfb_copyarea(struct fb_info *info,
378 const struct fb_copyarea *area)
380 struct arcfb_par *par = info->par;
382 sys_copyarea(info, area);
384 /* update the physical lcd */
385 arcfb_lcd_update(par, area->dx, area->dy, area->width, area->height);
388 static void arcfb_imageblit(struct fb_info *info, const struct fb_image *image)
390 struct arcfb_par *par = info->par;
392 sys_imageblit(info, image);
394 /* update the physical lcd */
395 arcfb_lcd_update(par, image->dx, image->dy, image->width,
399 static int arcfb_ioctl(struct fb_info *info,
400 unsigned int cmd, unsigned long arg)
402 void __user *argp = (void __user *)arg;
403 struct arcfb_par *par = info->par;
410 /* illegal to wait on arc if no irq will occur */
414 /* wait until the Arc has generated an interrupt
415 * which will wake us up */
416 spin_lock_irqsave(&par->lock, flags);
417 prepare_to_wait(&arcfb_waitq, &wait,
419 spin_unlock_irqrestore(&par->lock, flags);
421 finish_wait(&arcfb_waitq, &wait);
423 case FBIO_GETCONTROL2:
427 ctl2 = ks108_readb_ctl2(info->par);
428 if (copy_to_user(argp, &ctl2, sizeof(ctl2)))
438 * this is the access path from userspace. they can seek and write to
439 * the fb. it's inefficient for them to do anything less than 64*8
440 * writes since we update the lcd in each write() anyway.
442 static ssize_t arcfb_write(struct fb_info *info, const char __user *buf,
443 size_t count, loff_t *ppos)
445 /* modded from epson 1355 */
449 unsigned int fbmemlength,x,y,w,h, bitppos, startpos, endpos, bitcount;
450 struct arcfb_par *par;
455 xres = info->var.xres;
456 fbmemlength = (xres * info->var.yres)/8;
462 if ((count + p) > fbmemlength) {
463 count = fbmemlength - p;
470 base_addr = (char __force *)info->screen_base;
471 count -= copy_from_user(base_addr + p, buf, count);
478 startpos = floorXres(bitppos, xres);
479 endpos = ceilXres((bitppos + (count*8)), xres);
480 bitcount = endpos - startpos;
486 arcfb_lcd_update(par, x, y, w, h);
493 static struct fb_ops arcfb_ops = {
494 .owner = THIS_MODULE,
495 .fb_open = arcfb_open,
496 .fb_read = fb_sys_read,
497 .fb_write = arcfb_write,
498 .fb_release = arcfb_release,
499 .fb_pan_display = arcfb_pan_display,
500 .fb_fillrect = arcfb_fillrect,
501 .fb_copyarea = arcfb_copyarea,
502 .fb_imageblit = arcfb_imageblit,
503 .fb_ioctl = arcfb_ioctl,
506 static int __devinit arcfb_probe(struct platform_device *dev)
508 struct fb_info *info;
509 int retval = -ENOMEM;
511 unsigned char *videomemory;
512 struct arcfb_par *par;
515 videomemorysize = (((64*64)*num_cols)*num_rows)/8;
517 /* We need a flat backing store for the Arc's
518 less-flat actual paged framebuffer */
519 if (!(videomemory = vmalloc(videomemorysize)))
522 memset(videomemory, 0, videomemorysize);
524 info = framebuffer_alloc(sizeof(struct arcfb_par), &dev->dev);
528 info->screen_base = (char __iomem *)videomemory;
529 info->fbops = &arcfb_ops;
531 info->var = arcfb_var;
532 info->fix = arcfb_fix;
536 if (!dio_addr || !cio_addr || !c2io_addr) {
537 printk(KERN_WARNING "no IO addresses supplied\n");
540 par->dio_addr = dio_addr;
541 par->cio_addr = cio_addr;
542 par->c2io_addr = c2io_addr;
543 par->cslut[0] = 0x00;
544 par->cslut[1] = 0x06;
545 info->flags = FBINFO_FLAG_DEFAULT;
546 spin_lock_init(&par->lock);
547 retval = register_framebuffer(info);
550 platform_set_drvdata(dev, info);
553 if (request_irq(par->irq, &arcfb_interrupt, IRQF_SHARED,
556 "arcfb: Failed req IRQ %d\n", par->irq);
561 "fb%d: Arc frame buffer device, using %dK of video memory\n",
562 info->node, videomemorysize >> 10);
564 /* this inits the lcd but doesn't clear dirty pixels */
565 for (i = 0; i < num_cols * num_rows; i++) {
566 ks108_writeb_ctl(par, i, KS_DPY_OFF);
567 ks108_set_start_line(par, i, 0);
568 ks108_set_yaddr(par, i, 0);
569 ks108_set_xaddr(par, i, 0);
570 ks108_writeb_ctl(par, i, KS_DPY_ON);
573 /* if we were told to splash the screen, we just clear it */
575 for (i = 0; i < num_cols * num_rows; i++) {
576 printk(KERN_INFO "fb%d: splashing lcd %d\n",
578 ks108_set_start_line(par, i, 0);
579 ks108_clear_lcd(par, i);
585 framebuffer_release(info);
591 static int __devexit arcfb_remove(struct platform_device *dev)
593 struct fb_info *info = platform_get_drvdata(dev);
596 unregister_framebuffer(info);
597 vfree((void __force *)info->screen_base);
598 framebuffer_release(info);
603 static struct platform_driver arcfb_driver = {
604 .probe = arcfb_probe,
605 .remove = __devexit_p(arcfb_remove),
611 static struct platform_device *arcfb_device;
613 static int __init arcfb_init(void)
620 ret = platform_driver_register(&arcfb_driver);
622 arcfb_device = platform_device_alloc("arcfb", 0);
624 ret = platform_device_add(arcfb_device);
629 platform_device_put(arcfb_device);
630 platform_driver_unregister(&arcfb_driver);
637 static void __exit arcfb_exit(void)
639 platform_device_unregister(arcfb_device);
640 platform_driver_unregister(&arcfb_driver);
643 module_param(num_cols, ulong, 0);
644 MODULE_PARM_DESC(num_cols, "Num horiz panels, eg: 2 = 128 bit wide");
645 module_param(num_rows, ulong, 0);
646 MODULE_PARM_DESC(num_rows, "Num vert panels, eg: 1 = 64 bit high");
647 module_param(nosplash, uint, 0);
648 MODULE_PARM_DESC(nosplash, "Disable doing the splash screen");
649 module_param(arcfb_enable, uint, 0);
650 MODULE_PARM_DESC(arcfb_enable, "Enable communication with Arc board");
651 module_param(dio_addr, ulong, 0);
652 MODULE_PARM_DESC(dio_addr, "IO address for data, eg: 0x480");
653 module_param(cio_addr, ulong, 0);
654 MODULE_PARM_DESC(cio_addr, "IO address for control, eg: 0x400");
655 module_param(c2io_addr, ulong, 0);
656 MODULE_PARM_DESC(c2io_addr, "IO address for secondary control, eg: 0x408");
657 module_param(splashval, ulong, 0);
658 MODULE_PARM_DESC(splashval, "Splash pattern: 0xFF is black, 0x00 is green");
659 module_param(tuhold, ulong, 0);
660 MODULE_PARM_DESC(tuhold, "Time to hold between strobing data to Arc board");
661 module_param(irq, uint, 0);
662 MODULE_PARM_DESC(irq, "IRQ for the Arc board");
664 module_init(arcfb_init);
665 module_exit(arcfb_exit);
667 MODULE_DESCRIPTION("fbdev driver for Arc monochrome LCD board");
668 MODULE_AUTHOR("Jaya Kumar");
669 MODULE_LICENSE("GPL");