/* * linux/drivers/video/hecubafb.c -- FB driver for Hecuba/Apollo controller * * Copyright (C) 2006, Jaya Kumar * This work was sponsored by CIS(M) Sdn Bhd * * This file is subject to the terms and conditions of the GNU General Public * License. See the file COPYING in the main directory of this archive for * more details. * * Layout is based on skeletonfb.c by James Simmons and Geert Uytterhoeven. * This work was possible because of apollo display code from E-Ink's website * http://support.eink.com/community * All information used to write this code is from public material made * available by E-Ink on its support site. Some commands such as 0xA4 * were found by looping through cmd=0x00 thru 0xFF and supplying random * values. There are other commands that the display is capable of, * beyond the 5 used here but they are more complex. * * This driver is written to be used with the Hecuba display architecture. * The actual display chip is called Apollo and the interface electronics * it needs is called Hecuba. * * It is intended to be architecture independent. A board specific driver * must be used to perform all the physical IO interactions. An example * is provided as n411.c * */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/errno.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/vmalloc.h> #include <linux/delay.h> #include <linux/interrupt.h> #include <linux/fb.h> #include <linux/init.h> #include <linux/platform_device.h> #include <linux/list.h> #include <linux/uaccess.h> #include <video/hecubafb.h> /* Display specific information */ #define DPY_W 600 #define DPY_H 800 static struct fb_fix_screeninfo hecubafb_fix = { .id = "hecubafb", .type = FB_TYPE_PACKED_PIXELS, .visual = FB_VISUAL_MONO01, .xpanstep = 0, .ypanstep = 0, .ywrapstep = 0, .line_length = DPY_W, .accel = FB_ACCEL_NONE, }; static struct fb_var_screeninfo hecubafb_var = { .xres = DPY_W, .yres = DPY_H, .xres_virtual = DPY_W, .yres_virtual = DPY_H, .bits_per_pixel = 1, .nonstd = 1, }; /* main hecubafb functions */ static void apollo_send_data(struct hecubafb_par *par, unsigned char data) { /* set data */ par->board->set_data(par, data); /* set DS low */ par->board->set_ctl(par, HCB_DS_BIT, 0); /* wait for ack */ par->board->wait_for_ack(par, 0); /* set DS hi */ par->board->set_ctl(par, HCB_DS_BIT, 1); /* wait for ack to clear */ par->board->wait_for_ack(par, 1); } static void apollo_send_command(struct hecubafb_par *par, unsigned char data) { /* command so set CD to high */ par->board->set_ctl(par, HCB_CD_BIT, 1); /* actually strobe with command */ apollo_send_data(par, data); /* clear CD back to low */ par->board->set_ctl(par, HCB_CD_BIT, 0); } static void hecubafb_dpy_update(struct hecubafb_par *par) { int i; unsigned char *buf = (unsigned char __force *)par->info->screen_base; apollo_send_command(par, APOLLO_START_NEW_IMG); for (i=0; i < (DPY_W*DPY_H/8); i++) { apollo_send_data(par, *(buf++)); } apollo_send_command(par, APOLLO_STOP_IMG_DATA); apollo_send_command(par, APOLLO_DISPLAY_IMG); } /* this is called back from the deferred io workqueue */ static void hecubafb_dpy_deferred_io(struct fb_info *info, struct list_head *pagelist) { hecubafb_dpy_update(info->par); } static void hecubafb_fillrect(struct fb_info *info, const struct fb_fillrect *rect) { struct hecubafb_par *par = info->par; sys_fillrect(info, rect); hecubafb_dpy_update(par); } static void hecubafb_copyarea(struct fb_info *info, const struct fb_copyarea *area) { struct hecubafb_par *par = info->par; sys_copyarea(info, area); hecubafb_dpy_update(par); } static void hecubafb_imageblit(struct fb_info *info, const struct fb_image *image) { struct hecubafb_par *par = info->par; sys_imageblit(info, image); hecubafb_dpy_update(par); } /* * this is the slow path from userspace. they can seek and write to * the fb. it's inefficient to do anything less than a full screen draw */ static ssize_t hecubafb_write(struct fb_info *info, const char __user *buf, size_t count, loff_t *ppos) { struct hecubafb_par *par = info->par; unsigned long p = *ppos; void *dst; int err = 0; unsigned long total_size; if (info->state != FBINFO_STATE_RUNNING) return -EPERM; total_size = info->fix.smem_len; if (p > total_size) return -EFBIG; if (count > total_size) { err = -EFBIG; count = total_size; } if (count + p > total_size) { if (!err) err = -ENOSPC; count = total_size - p; } dst = (void __force *) (info->screen_base + p); if (copy_from_user(dst, buf, count)) err = -EFAULT; if (!err) *ppos += count; hecubafb_dpy_update(par); return (err) ? err : count; } static struct fb_ops hecubafb_ops = { .owner = THIS_MODULE, .fb_read = fb_sys_read, .fb_write = hecubafb_write, .fb_fillrect = hecubafb_fillrect, .fb_copyarea = hecubafb_copyarea, .fb_imageblit = hecubafb_imageblit, }; static struct fb_deferred_io hecubafb_defio = { .delay = HZ, .deferred_io = hecubafb_dpy_deferred_io, }; static int hecubafb_probe(struct platform_device *dev) { struct fb_info *info; struct hecuba_board *board; int retval = -ENOMEM; int videomemorysize; unsigned char *videomemory; struct hecubafb_par *par; /* pick up board specific routines */ board = dev->dev.platform_data; if (!board) return -EINVAL; /* try to count device specific driver, if can't, platform recalls */ if (!try_module_get(board->owner)) return -ENODEV; videomemorysize = (DPY_W*DPY_H)/8; videomemory = vzalloc(videomemorysize); if (!videomemory) goto err_videomem_alloc; info = framebuffer_alloc(sizeof(struct hecubafb_par), &dev->dev); if (!info) goto err_fballoc; info->screen_base = (char __force __iomem *)videomemory; info->fbops = &hecubafb_ops; info->var = hecubafb_var; info->fix = hecubafb_fix; info->fix.smem_len = videomemorysize; par = info->par; par->info = info; par->board = board; par->send_command = apollo_send_command; par->send_data = apollo_send_data; info->flags = FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB; info->fbdefio = &hecubafb_defio; fb_deferred_io_init(info); retval = register_framebuffer(info); if (retval < 0) goto err_fbreg; platform_set_drvdata(dev, info); printk(KERN_INFO "fb%d: Hecuba frame buffer device, using %dK of video memory\n", info->node, videomemorysize >> 10); /* this inits the dpy */ retval = par->board->init(par); if (retval < 0) goto err_fbreg; return 0; err_fbreg: framebuffer_release(info); err_fballoc: vfree(videomemory); err_videomem_alloc: module_put(board->owner); return retval; } static int hecubafb_remove(struct platform_device *dev) { struct fb_info *info = platform_get_drvdata(dev); if (info) { struct hecubafb_par *par = info->par; fb_deferred_io_cleanup(info); unregister_framebuffer(info); vfree((void __force *)info->screen_base); if (par->board->remove) par->board->remove(par); module_put(par->board->owner); framebuffer_release(info); } return 0; } static struct platform_driver hecubafb_driver = { .probe = hecubafb_probe, .remove = hecubafb_remove, .driver = { .owner = THIS_MODULE, .name = "hecubafb", }, }; static int __init hecubafb_init(void) { return platform_driver_register(&hecubafb_driver); } static void __exit hecubafb_exit(void) { platform_driver_unregister(&hecubafb_driver); } module_init(hecubafb_init); module_exit(hecubafb_exit); MODULE_DESCRIPTION("fbdev driver for Hecuba/Apollo controller"); MODULE_AUTHOR("Jaya Kumar"); MODULE_LICENSE("GPL");