1/* 2 * linux/drivers/video/hecubafb.c -- FB driver for Hecuba 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 controller 21 * board, and tested with the EInk 800x600 display in 1 bit mode. 22 * The interface between Hecuba and the host is TTL based GPIO. The 23 * GPIO requirements are 8 writable data lines and 6 lines for control. 24 * Only 4 of the controls are actually used here but 6 for future use. 25 * The driver requires the IO addresses for data and control GPIO at 26 * load time. It is also possible to use this display with a standard 27 * PC parallel port. 28 * 29 * General notes: 30 * - User must set hecubafb_enable=1 to enable it 31 * - User must set dio_addr=0xIOADDR cio_addr=0xIOADDR c2io_addr=0xIOADDR 32 * 33 */ 34 35#include <linux/module.h> 36#include <linux/kernel.h> 37#include <linux/errno.h> 38#include <linux/string.h> 39#include <linux/mm.h> 40#include <linux/slab.h> 41#include <linux/vmalloc.h> 42#include <linux/delay.h> 43#include <linux/interrupt.h> 44#include <linux/fb.h> 45#include <linux/init.h> 46#include <linux/platform_device.h> 47#include <linux/list.h> 48#include <asm/uaccess.h> 49 50/* Apollo controller specific defines */ 51#define APOLLO_START_NEW_IMG 0xA0 52#define APOLLO_STOP_IMG_DATA 0xA1 53#define APOLLO_DISPLAY_IMG 0xA2 54#define APOLLO_ERASE_DISPLAY 0xA3 55#define APOLLO_INIT_DISPLAY 0xA4 56 57/* Hecuba interface specific defines */ 58/* WUP is inverted, CD is inverted, DS is inverted */ 59#define HCB_NWUP_BIT 0x01 60#define HCB_NDS_BIT 0x02 61#define HCB_RW_BIT 0x04 62#define HCB_NCD_BIT 0x08 63#define HCB_ACK_BIT 0x80 64 65/* Display specific information */ 66#define DPY_W 600 67#define DPY_H 800 68 69struct hecubafb_par { 70 unsigned long dio_addr; 71 unsigned long cio_addr; 72 unsigned long c2io_addr; 73 unsigned char ctl; 74 struct fb_info *info; 75 unsigned int irq; 76}; 77 78static struct fb_fix_screeninfo hecubafb_fix __devinitdata = { 79 .id = "hecubafb", 80 .type = FB_TYPE_PACKED_PIXELS, 81 .visual = FB_VISUAL_MONO01, 82 .xpanstep = 0, 83 .ypanstep = 0, 84 .ywrapstep = 0, 85 .accel = FB_ACCEL_NONE, 86}; 87 88static struct fb_var_screeninfo hecubafb_var __devinitdata = { 89 .xres = DPY_W, 90 .yres = DPY_H, 91 .xres_virtual = DPY_W, 92 .yres_virtual = DPY_H, 93 .bits_per_pixel = 1, 94 .nonstd = 1, 95}; 96 97static unsigned long dio_addr; 98static unsigned long cio_addr; 99static unsigned long c2io_addr; 100static unsigned long splashval; 101static unsigned int nosplash; 102static unsigned int hecubafb_enable; 103static unsigned int irq; 104 105static DECLARE_WAIT_QUEUE_HEAD(hecubafb_waitq); 106 107static void hcb_set_ctl(struct hecubafb_par *par) 108{ 109 outb(par->ctl, par->cio_addr); 110} 111 112static unsigned char hcb_get_ctl(struct hecubafb_par *par) 113{ 114 return inb(par->c2io_addr); 115} 116 117static void hcb_set_data(struct hecubafb_par *par, unsigned char value) 118{ 119 outb(value, par->dio_addr); 120} 121 122static int __devinit apollo_init_control(struct hecubafb_par *par) 123{ 124 unsigned char ctl; 125 /* for init, we want the following setup to be set: 126 WUP = lo 127 ACK = hi 128 DS = hi 129 RW = hi 130 CD = lo 131 */ 132 133 /* write WUP to lo, DS to hi, RW to hi, CD to lo */ 134 par->ctl = HCB_NWUP_BIT | HCB_RW_BIT | HCB_NCD_BIT ; 135 par->ctl &= ~HCB_NDS_BIT; 136 hcb_set_ctl(par); 137 138 /* check ACK is not lo */ 139 ctl = hcb_get_ctl(par); 140 if ((ctl & HCB_ACK_BIT)) { 141 printk(KERN_ERR "Fail because ACK is already low\n"); 142 return -ENXIO; 143 } 144 145 return 0; 146} 147 148static void hcb_wait_for_ack(struct hecubafb_par *par) 149{ 150 151 int timeout; 152 unsigned char ctl; 153 154 timeout=500; 155 do { 156 ctl = hcb_get_ctl(par); 157 if ((ctl & HCB_ACK_BIT)) 158 return; 159 udelay(1); 160 } while (timeout--); 161 printk(KERN_ERR "timed out waiting for ack\n"); 162} 163 164static void hcb_wait_for_ack_clear(struct hecubafb_par *par) 165{ 166 167 int timeout; 168 unsigned char ctl; 169 170 timeout=500; 171 do { 172 ctl = hcb_get_ctl(par); 173 if (!(ctl & HCB_ACK_BIT)) 174 return; 175 udelay(1); 176 } while (timeout--); 177 printk(KERN_ERR "timed out waiting for clear\n"); 178} 179 180static void apollo_send_data(struct hecubafb_par *par, unsigned char data) 181{ 182 /* set data */ 183 hcb_set_data(par, data); 184 185 /* set DS low */ 186 par->ctl |= HCB_NDS_BIT; 187 hcb_set_ctl(par); 188 189 hcb_wait_for_ack(par); 190 191 /* set DS hi */ 192 par->ctl &= ~(HCB_NDS_BIT); 193 hcb_set_ctl(par); 194 195 hcb_wait_for_ack_clear(par); 196} 197 198static void apollo_send_command(struct hecubafb_par *par, unsigned char data) 199{ 200 /* command so set CD to high */ 201 par->ctl &= ~(HCB_NCD_BIT); 202 hcb_set_ctl(par); 203 204 /* actually strobe with command */ 205 apollo_send_data(par, data); 206 207 /* clear CD back to low */ 208 par->ctl |= (HCB_NCD_BIT); 209 hcb_set_ctl(par); 210} 211 212/* main hecubafb functions */ 213 214static void hecubafb_dpy_update(struct hecubafb_par *par) 215{ 216 int i; 217 unsigned char *buf = (unsigned char __force *)par->info->screen_base; 218 219 apollo_send_command(par, 0xA0); 220 221 for (i=0; i < (DPY_W*DPY_H/8); i++) { 222 apollo_send_data(par, *(buf++)); 223 } 224 225 apollo_send_command(par, 0xA1); 226 apollo_send_command(par, 0xA2); 227} 228 229/* this is called back from the deferred io workqueue */ 230static void hecubafb_dpy_deferred_io(struct fb_info *info, 231 struct list_head *pagelist) 232{ 233 hecubafb_dpy_update(info->par); 234} 235 236static void hecubafb_fillrect(struct fb_info *info, 237 const struct fb_fillrect *rect) 238{ 239 struct hecubafb_par *par = info->par; 240 241 sys_fillrect(info, rect); 242 243 hecubafb_dpy_update(par); 244} 245 246static void hecubafb_copyarea(struct fb_info *info, 247 const struct fb_copyarea *area) 248{ 249 struct hecubafb_par *par = info->par; 250 251 sys_copyarea(info, area); 252 253 hecubafb_dpy_update(par); 254} 255 256static void hecubafb_imageblit(struct fb_info *info, 257 const struct fb_image *image) 258{ 259 struct hecubafb_par *par = info->par; 260 261 sys_imageblit(info, image); 262 263 hecubafb_dpy_update(par); 264} 265 266/* 267 * this is the slow path from userspace. they can seek and write to 268 * the fb. it's inefficient to do anything less than a full screen draw 269 */ 270static ssize_t hecubafb_write(struct fb_info *info, const char __user *buf, 271 size_t count, loff_t *ppos) 272{ 273 unsigned long p; 274 int err=-EINVAL; 275 struct hecubafb_par *par; 276 unsigned int xres; 277 unsigned int fbmemlength; 278 279 p = *ppos; 280 par = info->par; 281 xres = info->var.xres; 282 fbmemlength = (xres * info->var.yres)/8; 283 284 if (p > fbmemlength) 285 return -ENOSPC; 286 287 err = 0; 288 if ((count + p) > fbmemlength) { 289 count = fbmemlength - p; 290 err = -ENOSPC; 291 } 292 293 if (count) { 294 char *base_addr; 295 296 base_addr = (char __force *)info->screen_base; 297 count -= copy_from_user(base_addr + p, buf, count); 298 *ppos += count; 299 err = -EFAULT; 300 } 301 302 hecubafb_dpy_update(par); 303 304 if (count) 305 return count; 306 307 return err; 308} 309 310static struct fb_ops hecubafb_ops = { 311 .owner = THIS_MODULE, 312 .fb_read = fb_sys_read, 313 .fb_write = hecubafb_write, 314 .fb_fillrect = hecubafb_fillrect, 315 .fb_copyarea = hecubafb_copyarea, 316 .fb_imageblit = hecubafb_imageblit, 317}; 318 319static struct fb_deferred_io hecubafb_defio = { 320 .delay = HZ, 321 .deferred_io = hecubafb_dpy_deferred_io, 322}; 323 324static int __devinit hecubafb_probe(struct platform_device *dev) 325{ 326 struct fb_info *info; 327 int retval = -ENOMEM; 328 int videomemorysize; 329 unsigned char *videomemory; 330 struct hecubafb_par *par; 331 332 videomemorysize = (DPY_W*DPY_H)/8; 333 334 if (!(videomemory = vmalloc(videomemorysize))) 335 return retval; 336 337 memset(videomemory, 0, videomemorysize); 338 339 info = framebuffer_alloc(sizeof(struct hecubafb_par), &dev->dev); 340 if (!info) 341 goto err; 342 343 info->screen_base = (char __iomem *) videomemory; 344 info->fbops = &hecubafb_ops; 345 346 info->var = hecubafb_var; 347 info->fix = hecubafb_fix; 348 info->fix.smem_len = videomemorysize; 349 par = info->par; 350 par->info = info; 351 352 if (!dio_addr || !cio_addr || !c2io_addr) { 353 printk(KERN_WARNING "no IO addresses supplied\n"); 354 goto err1; 355 } 356 par->dio_addr = dio_addr; 357 par->cio_addr = cio_addr; 358 par->c2io_addr = c2io_addr; 359 info->flags = FBINFO_FLAG_DEFAULT; 360 361 info->fbdefio = &hecubafb_defio; 362 fb_deferred_io_init(info); 363 364 retval = register_framebuffer(info); 365 if (retval < 0) 366 goto err1; 367 platform_set_drvdata(dev, info); 368 369 printk(KERN_INFO 370 "fb%d: Hecuba frame buffer device, using %dK of video memory\n", 371 info->node, videomemorysize >> 10); 372 373 /* this inits the dpy */ 374 apollo_init_control(par); 375 376 apollo_send_command(par, APOLLO_INIT_DISPLAY); 377 apollo_send_data(par, 0x81); 378 379 /* have to wait while display resets */ 380 udelay(1000); 381 382 /* if we were told to splash the screen, we just clear it */ 383 if (!nosplash) { 384 apollo_send_command(par, APOLLO_ERASE_DISPLAY); 385 apollo_send_data(par, splashval); 386 } 387 388 return 0; 389err1: 390 framebuffer_release(info); 391err: 392 vfree(videomemory); 393 return retval; 394} 395 396static int __devexit hecubafb_remove(struct platform_device *dev) 397{ 398 struct fb_info *info = platform_get_drvdata(dev); 399 400 if (info) { 401 fb_deferred_io_cleanup(info); 402 unregister_framebuffer(info); 403 vfree((void __force *)info->screen_base); 404 framebuffer_release(info); 405 } 406 return 0; 407} 408 409static struct platform_driver hecubafb_driver = { 410 .probe = hecubafb_probe, 411 .remove = hecubafb_remove, 412 .driver = { 413 .name = "hecubafb", 414 }, 415}; 416 417static struct platform_device *hecubafb_device; 418 419static int __init hecubafb_init(void) 420{ 421 int ret; 422 423 if (!hecubafb_enable) { 424 printk(KERN_ERR "Use hecubafb_enable to enable the device\n"); 425 return -ENXIO; 426 } 427 428 ret = platform_driver_register(&hecubafb_driver); 429 if (!ret) { 430 hecubafb_device = platform_device_alloc("hecubafb", 0); 431 if (hecubafb_device) 432 ret = platform_device_add(hecubafb_device); 433 else 434 ret = -ENOMEM; 435 436 if (ret) { 437 platform_device_put(hecubafb_device); 438 platform_driver_unregister(&hecubafb_driver); 439 } 440 } 441 return ret; 442 443} 444 445static void __exit hecubafb_exit(void) 446{ 447 platform_device_unregister(hecubafb_device); 448 platform_driver_unregister(&hecubafb_driver); 449} 450 451module_param(nosplash, uint, 0); 452MODULE_PARM_DESC(nosplash, "Disable doing the splash screen"); 453module_param(hecubafb_enable, uint, 0); 454MODULE_PARM_DESC(hecubafb_enable, "Enable communication with Hecuba board"); 455module_param(dio_addr, ulong, 0); 456MODULE_PARM_DESC(dio_addr, "IO address for data, eg: 0x480"); 457module_param(cio_addr, ulong, 0); 458MODULE_PARM_DESC(cio_addr, "IO address for control, eg: 0x400"); 459module_param(c2io_addr, ulong, 0); 460MODULE_PARM_DESC(c2io_addr, "IO address for secondary control, eg: 0x408"); 461module_param(splashval, ulong, 0); 462MODULE_PARM_DESC(splashval, "Splash pattern: 0x00 is black, 0x01 is white"); 463module_param(irq, uint, 0); 464MODULE_PARM_DESC(irq, "IRQ for the Hecuba board"); 465 466module_init(hecubafb_init); 467module_exit(hecubafb_exit); 468 469MODULE_DESCRIPTION("fbdev driver for Hecuba board"); 470MODULE_AUTHOR("Jaya Kumar"); 471MODULE_LICENSE("GPL"); 472