Commit aad09e51 authored by Jaya Kumar's avatar Jaya Kumar Committed by Linus Torvalds
Browse files

fbdev: hecuba Framebuffer Driver 



This patch implements support for the E-Ink/hecuba display device.  It uses
deferred IO support.

[akpm@linux-foundation.org: linker section fixes]
Signed-off-by: default avatarJaya Kumar <jayakumar.lkml@gmail.com>
Signed-off-by: default avatarAntonino Daplas <adaplas@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 5e841b88

drivers/video/Kconfig

+14 −0
Original line number Diff line number Diff line
@@ -557,6 +557,20 @@ config FB_IMAC 
	help

	  This is the frame buffer device driver for the Intel-based Macintosh



config FB_HECUBA

       tristate "Hecuba board support"

       depends on FB && X86 && MMU

       select FB_CFB_FILLRECT

       select FB_CFB_COPYAREA

       select FB_CFB_IMAGEBLIT

       select FB_DEFERRED_IO

       help

         This enables support for the Hecuba board. This driver was tested

         with an E-Ink 800x600 display and x86 SBCs through a 16 bit GPIO

         interface (8 bit data, 4 bit control). If you anticpate using

         this driver, say Y or M; otherwise say N. You must specify the

         GPIO IO address to be used for setting control and data.



config FB_HGA

	tristate "Hercules mono graphics support"

	depends on FB && X86

drivers/video/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -67,6 +67,7 @@ obj-$(CONFIG_FB_ACORN) += acornfb.o 
obj-$(CONFIG_FB_ATARI)            += atafb.o c2p.o atafb_mfb.o \

                                     atafb_iplan2p2.o atafb_iplan2p4.o atafb_iplan2p8.o

obj-$(CONFIG_FB_MAC)              += macfb.o

obj-$(CONFIG_FB_HECUBA)           += hecubafb.o

obj-$(CONFIG_FB_HGA)              += hgafb.o

obj-$(CONFIG_FB_XVR500)           += sunxvr500.o

obj-$(CONFIG_FB_XVR2500)          += sunxvr2500.o

drivers/video/hecubafb.c

0 → 100644
+480 −0
Original line number Diff line number Diff line 
/*

 * linux/drivers/video/hecubafb.c -- FB driver for Hecuba 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 controller

 * board, and tested with the EInk 800x600 display in 1 bit mode.

 * The interface between Hecuba and the host is TTL based GPIO. The

 * GPIO requirements are 8 writable data lines and 6 lines for control.

 * Only 4 of the controls are actually used here but 6 for future use.

 * The driver requires the IO addresses for data and control GPIO at

 * load time. It is also possible to use this display with a standard

 * PC parallel port.

 *

 * General notes:

 * - User must set hecubafb_enable=1 to enable it

 * - User must set dio_addr=0xIOADDR cio_addr=0xIOADDR c2io_addr=0xIOADDR

 *

 */



#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/string.h>

#include <linux/mm.h>

#include <linux/slab.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 <asm/uaccess.h>



/* Apollo controller specific defines */

#define APOLLO_START_NEW_IMG	0xA0

#define APOLLO_STOP_IMG_DATA	0xA1

#define APOLLO_DISPLAY_IMG	0xA2

#define APOLLO_ERASE_DISPLAY	0xA3

#define APOLLO_INIT_DISPLAY	0xA4



/* Hecuba interface specific defines */

/* WUP is inverted, CD is inverted, DS is inverted */

#define HCB_NWUP_BIT	0x01

#define HCB_NDS_BIT 	0x02

#define HCB_RW_BIT 	0x04

#define HCB_NCD_BIT 	0x08

#define HCB_ACK_BIT 	0x80



/* Display specific information */

#define DPY_W 600

#define DPY_H 800



struct hecubafb_par {

	unsigned long dio_addr;

	unsigned long cio_addr;

	unsigned long c2io_addr;

	unsigned char ctl;

	struct fb_info *info;

	unsigned int irq;

};



static struct fb_fix_screeninfo hecubafb_fix __devinitdata = {

	.id =		"hecubafb",

	.type =		FB_TYPE_PACKED_PIXELS,

	.visual =	FB_VISUAL_MONO01,

	.xpanstep =	0,

	.ypanstep =	0,

	.ywrapstep =	0,

	.accel =	FB_ACCEL_NONE,

};



static struct fb_var_screeninfo hecubafb_var __devinitdata = {

	.xres		= DPY_W,

	.yres		= DPY_H,

	.xres_virtual	= DPY_W,

	.yres_virtual	= DPY_H,

	.bits_per_pixel	= 1,

	.nonstd		= 1,

};



static unsigned long dio_addr;

static unsigned long cio_addr;

static unsigned long c2io_addr;

static unsigned long splashval;

static unsigned int nosplash;

static unsigned int hecubafb_enable;

static unsigned int irq;



static DECLARE_WAIT_QUEUE_HEAD(hecubafb_waitq);



static void hcb_set_ctl(struct hecubafb_par *par)

{

	outb(par->ctl, par->cio_addr);

}



static unsigned char hcb_get_ctl(struct hecubafb_par *par)

{

	return inb(par->c2io_addr);

}



static void hcb_set_data(struct hecubafb_par *par, unsigned char value)

{

	outb(value, par->dio_addr);

}



static int __devinit apollo_init_control(struct hecubafb_par *par)

{

	unsigned char ctl;

	/* for init, we want the following setup to be set:

	WUP = lo

	ACK = hi

	DS = hi

	RW = hi

	CD = lo

	*/



	/* write WUP to lo, DS to hi, RW to hi, CD to lo */

	par->ctl = HCB_NWUP_BIT | HCB_RW_BIT | HCB_NCD_BIT ;

	par->ctl &= ~HCB_NDS_BIT;

	hcb_set_ctl(par);



	/* check ACK is not lo */

	ctl = hcb_get_ctl(par);

	if ((ctl & HCB_ACK_BIT)) {

		printk(KERN_ERR "Fail because ACK is already low\n");

		return -ENXIO;

	}



	return 0;

}



void hcb_wait_for_ack(struct hecubafb_par *par)

{



	int timeout;

	unsigned char ctl;



	timeout=500;

	do {

		ctl = hcb_get_ctl(par);

		if ((ctl & HCB_ACK_BIT))

			return;

		udelay(1);

	} while (timeout--);

	printk(KERN_ERR "timed out waiting for ack\n");

}



void hcb_wait_for_ack_clear(struct hecubafb_par *par)

{



	int timeout;

	unsigned char ctl;



	timeout=500;

	do {

		ctl = hcb_get_ctl(par);

		if (!(ctl & HCB_ACK_BIT))

			return;

		udelay(1);

	} while (timeout--);

	printk(KERN_ERR "timed out waiting for clear\n");

}



void apollo_send_data(struct hecubafb_par *par, unsigned char data)

{

	/* set data */

	hcb_set_data(par, data);



	/* set DS low */

	par->ctl |= HCB_NDS_BIT;

	hcb_set_ctl(par);



	hcb_wait_for_ack(par);



	/* set DS hi */

	par->ctl &= ~(HCB_NDS_BIT);

	hcb_set_ctl(par);



	hcb_wait_for_ack_clear(par);

}



void apollo_send_command(struct hecubafb_par *par, unsigned char data)

{

	/* command so set CD to high */

	par->ctl &= ~(HCB_NCD_BIT);

	hcb_set_ctl(par);



	/* actually strobe with command */

	apollo_send_data(par, data);



	/* clear CD back to low */

	par->ctl |= (HCB_NCD_BIT);

	hcb_set_ctl(par);

}



/* main hecubafb functions */



static void hecubafb_dpy_update(struct hecubafb_par *par)

{

	int i;

	unsigned char *buf = par->info->screen_base;



	apollo_send_command(par, 0xA0);



	for (i=0; i < (DPY_W*DPY_H/8); i++) {

		apollo_send_data(par, *(buf++));

	}



	apollo_send_command(par, 0xA1);

	apollo_send_command(par, 0xA2);

}



/* 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;



	cfb_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;



	cfb_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;



	cfb_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 file *file, const char __user *buf,

				size_t count, loff_t *ppos)

{

	struct inode *inode;

	int fbidx;

	struct fb_info *info;

	unsigned long p;

	int err=-EINVAL;

	struct hecubafb_par *par;

	unsigned int xres;

	unsigned int fbmemlength;



	p = *ppos;

	inode = file->f_dentry->d_inode;

	fbidx = iminor(inode);

	info = registered_fb[fbidx];



	if (!info || !info->screen_base)

		return -ENODEV;



	par = info->par;

	xres = info->var.xres;

	fbmemlength = (xres * info->var.yres)/8;



	if (p > fbmemlength)

		return -ENOSPC;



	err = 0;

	if ((count + p) > fbmemlength) {

		count = fbmemlength - p;

		err = -ENOSPC;

	}



	if (count) {

		char *base_addr;



		base_addr = info->screen_base;

		count -= copy_from_user(base_addr + p, buf, count);

		*ppos += count;

		err = -EFAULT;

	}



	hecubafb_dpy_update(par);



	if (count)

		return count;



	return err;

}



static struct fb_ops hecubafb_ops = {

	.owner		= THIS_MODULE,

	.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 __devinit hecubafb_probe(struct platform_device *dev)

{

	struct fb_info *info;

	int retval = -ENOMEM;

	int videomemorysize;

	unsigned char *videomemory;

	struct hecubafb_par *par;



	videomemorysize = (DPY_W*DPY_H)/8;



	if (!(videomemory = vmalloc(videomemorysize)))

		return retval;



	memset(videomemory, 0, videomemorysize);



	info = framebuffer_alloc(sizeof(struct hecubafb_par), &dev->dev);

	if (!info)

		goto err;



	info->screen_base = (char __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;



	if (!dio_addr || !cio_addr || !c2io_addr) {

		printk(KERN_WARNING "no IO addresses supplied\n");

		goto err1;

	}

	par->dio_addr = dio_addr;

	par->cio_addr = cio_addr;

	par->c2io_addr = c2io_addr;

	info->flags = FBINFO_FLAG_DEFAULT;



	info->fbdefio = &hecubafb_defio;

	fb_deferred_io_init(info);



	retval = register_framebuffer(info);

	if (retval < 0)

		goto err1;

	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 */

	apollo_init_control(par);



	apollo_send_command(par, APOLLO_INIT_DISPLAY);

	apollo_send_data(par, 0x81);



	/* have to wait while display resets */

	udelay(1000);



	/* if we were told to splash the screen, we just clear it */

	if (!nosplash) {

		apollo_send_command(par, APOLLO_ERASE_DISPLAY);

		apollo_send_data(par, splashval);

	}



	return 0;

err1:

	framebuffer_release(info);

err:

	vfree(videomemory);

	return retval;

}



static int __devexit hecubafb_remove(struct platform_device *dev)

{

	struct fb_info *info = platform_get_drvdata(dev);



	if (info) {

		fb_deferred_io_cleanup(info);

		unregister_framebuffer(info);

		vfree(info->screen_base);

		framebuffer_release(info);

	}

	return 0;

}



static struct platform_driver hecubafb_driver = {

	.probe	= hecubafb_probe,

	.remove = hecubafb_remove,

	.driver	= {

		.name	= "hecubafb",

	},

};



static struct platform_device *hecubafb_device;



static int __init hecubafb_init(void)

{

	int ret;



	if (!hecubafb_enable) {

		printk(KERN_ERR "Use hecubafb_enable to enable the device\n");

		return -ENXIO;

	}



	ret = platform_driver_register(&hecubafb_driver);

	if (!ret) {

		hecubafb_device = platform_device_alloc("hecubafb", 0);

		if (hecubafb_device)

			ret = platform_device_add(hecubafb_device);

		else

			ret = -ENOMEM;



		if (ret) {

			platform_device_put(hecubafb_device);

			platform_driver_unregister(&hecubafb_driver);

		}

	}

	return ret;



}



static void __exit hecubafb_exit(void)

{

	platform_device_unregister(hecubafb_device);

	platform_driver_unregister(&hecubafb_driver);

}



module_param(nosplash, uint, 0);

MODULE_PARM_DESC(nosplash, "Disable doing the splash screen");

module_param(hecubafb_enable, uint, 0);

MODULE_PARM_DESC(hecubafb_enable, "Enable communication with Hecuba board");

module_param(dio_addr, ulong, 0);

MODULE_PARM_DESC(dio_addr, "IO address for data, eg: 0x480");

module_param(cio_addr, ulong, 0);

MODULE_PARM_DESC(cio_addr, "IO address for control, eg: 0x400");

module_param(c2io_addr, ulong, 0);

MODULE_PARM_DESC(c2io_addr, "IO address for secondary control, eg: 0x408");

module_param(splashval, ulong, 0);

MODULE_PARM_DESC(splashval, "Splash pattern: 0x00 is black, 0x01 is white");

module_param(irq, uint, 0);

MODULE_PARM_DESC(irq, "IRQ for the Hecuba board");



module_init(hecubafb_init);

module_exit(hecubafb_exit);



MODULE_DESCRIPTION("fbdev driver for Hecuba board");

MODULE_AUTHOR("Jaya Kumar");

MODULE_LICENSE("GPL");

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