248 lines · c
1/*2 * linux/drivers/video/hecubafb.c -- FB driver for Hecuba/Apollo controller3 *4 * Copyright (C) 2006, Jaya Kumar5 * This work was sponsored by CIS(M) Sdn Bhd6 *7 * This file is subject to the terms and conditions of the GNU General Public8 * License. See the file COPYING in the main directory of this archive for9 * 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 website13 * http://support.eink.com/community14 * All information used to write this code is from public material made15 * available by E-Ink on its support site. Some commands such as 0xA416 * were found by looping through cmd=0x00 thru 0xFF and supplying random17 * 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 architecture.21 * The actual display chip is called Apollo and the interface electronics22 * it needs is called Hecuba.23 *24 * It is intended to be architecture independent. A board specific driver25 * must be used to perform all the physical IO interactions. An example26 * is provided as n411.c27 *28 */29 30#include <linux/module.h>31#include <linux/kernel.h>32#include <linux/errno.h>33#include <linux/string.h>34#include <linux/mm.h>35#include <linux/vmalloc.h>36#include <linux/delay.h>37#include <linux/interrupt.h>38#include <linux/fb.h>39#include <linux/init.h>40#include <linux/platform_device.h>41#include <linux/list.h>42#include <linux/uaccess.h>43 44#include <video/hecubafb.h>45 46/* Display specific information */47#define DPY_W 60048#define DPY_H 80049 50static const struct fb_fix_screeninfo hecubafb_fix = {51 .id = "hecubafb",52 .type = FB_TYPE_PACKED_PIXELS,53 .visual = FB_VISUAL_MONO01,54 .xpanstep = 0,55 .ypanstep = 0,56 .ywrapstep = 0,57 .line_length = DPY_W,58 .accel = FB_ACCEL_NONE,59};60 61static const struct fb_var_screeninfo hecubafb_var = {62 .xres = DPY_W,63 .yres = DPY_H,64 .xres_virtual = DPY_W,65 .yres_virtual = DPY_H,66 .bits_per_pixel = 1,67 .nonstd = 1,68};69 70/* main hecubafb functions */71 72static void apollo_send_data(struct hecubafb_par *par, unsigned char data)73{74 /* set data */75 par->board->set_data(par, data);76 77 /* set DS low */78 par->board->set_ctl(par, HCB_DS_BIT, 0);79 80 /* wait for ack */81 par->board->wait_for_ack(par, 0);82 83 /* set DS hi */84 par->board->set_ctl(par, HCB_DS_BIT, 1);85 86 /* wait for ack to clear */87 par->board->wait_for_ack(par, 1);88}89 90static void apollo_send_command(struct hecubafb_par *par, unsigned char data)91{92 /* command so set CD to high */93 par->board->set_ctl(par, HCB_CD_BIT, 1);94 95 /* actually strobe with command */96 apollo_send_data(par, data);97 98 /* clear CD back to low */99 par->board->set_ctl(par, HCB_CD_BIT, 0);100}101 102static void hecubafb_dpy_update(struct hecubafb_par *par)103{104 int i;105 unsigned char *buf = par->info->screen_buffer;106 107 apollo_send_command(par, APOLLO_START_NEW_IMG);108 109 for (i=0; i < (DPY_W*DPY_H/8); i++) {110 apollo_send_data(par, *(buf++));111 }112 113 apollo_send_command(par, APOLLO_STOP_IMG_DATA);114 apollo_send_command(par, APOLLO_DISPLAY_IMG);115}116 117/* this is called back from the deferred io workqueue */118static void hecubafb_dpy_deferred_io(struct fb_info *info, struct list_head *pagereflist)119{120 hecubafb_dpy_update(info->par);121}122 123static void hecubafb_defio_damage_range(struct fb_info *info, off_t off, size_t len)124{125 struct hecubafb_par *par = info->par;126 127 hecubafb_dpy_update(par);128}129 130static void hecubafb_defio_damage_area(struct fb_info *info, u32 x, u32 y,131 u32 width, u32 height)132{133 struct hecubafb_par *par = info->par;134 135 hecubafb_dpy_update(par);136}137 138FB_GEN_DEFAULT_DEFERRED_SYSMEM_OPS(hecubafb,139 hecubafb_defio_damage_range,140 hecubafb_defio_damage_area)141 142static const struct fb_ops hecubafb_ops = {143 .owner = THIS_MODULE,144 FB_DEFAULT_DEFERRED_OPS(hecubafb),145};146 147static struct fb_deferred_io hecubafb_defio = {148 .delay = HZ,149 .deferred_io = hecubafb_dpy_deferred_io,150};151 152static int hecubafb_probe(struct platform_device *dev)153{154 struct fb_info *info;155 struct hecuba_board *board;156 int retval = -ENOMEM;157 int videomemorysize;158 unsigned char *videomemory;159 struct hecubafb_par *par;160 161 /* pick up board specific routines */162 board = dev->dev.platform_data;163 if (!board)164 return -EINVAL;165 166 /* try to count device specific driver, if can't, platform recalls */167 if (!try_module_get(board->owner))168 return -ENODEV;169 170 videomemorysize = (DPY_W*DPY_H)/8;171 172 videomemory = vzalloc(videomemorysize);173 if (!videomemory)174 goto err_videomem_alloc;175 176 info = framebuffer_alloc(sizeof(struct hecubafb_par), &dev->dev);177 if (!info)178 goto err_fballoc;179 180 info->screen_buffer = videomemory;181 info->fbops = &hecubafb_ops;182 183 info->var = hecubafb_var;184 info->fix = hecubafb_fix;185 info->fix.smem_len = videomemorysize;186 par = info->par;187 par->info = info;188 par->board = board;189 par->send_command = apollo_send_command;190 par->send_data = apollo_send_data;191 192 info->flags = FBINFO_VIRTFB;193 194 info->fbdefio = &hecubafb_defio;195 fb_deferred_io_init(info);196 197 retval = register_framebuffer(info);198 if (retval < 0)199 goto err_fbreg;200 platform_set_drvdata(dev, info);201 202 fb_info(info, "Hecuba frame buffer device, using %dK of video memory\n",203 videomemorysize >> 10);204 205 /* this inits the dpy */206 retval = par->board->init(par);207 if (retval < 0)208 goto err_fbreg;209 210 return 0;211err_fbreg:212 framebuffer_release(info);213err_fballoc:214 vfree(videomemory);215err_videomem_alloc:216 module_put(board->owner);217 return retval;218}219 220static void hecubafb_remove(struct platform_device *dev)221{222 struct fb_info *info = platform_get_drvdata(dev);223 224 if (info) {225 struct hecubafb_par *par = info->par;226 fb_deferred_io_cleanup(info);227 unregister_framebuffer(info);228 vfree(info->screen_buffer);229 if (par->board->remove)230 par->board->remove(par);231 module_put(par->board->owner);232 framebuffer_release(info);233 }234}235 236static struct platform_driver hecubafb_driver = {237 .probe = hecubafb_probe,238 .remove = hecubafb_remove,239 .driver = {240 .name = "hecubafb",241 },242};243module_platform_driver(hecubafb_driver);244 245MODULE_DESCRIPTION("fbdev driver for Hecuba/Apollo controller");246MODULE_AUTHOR("Jaya Kumar");247MODULE_LICENSE("GPL");248