/*
* linux/drivers/video/arcfb.c -- FB driver for Arc monochrome LCD board
*
* Copyright (C) 2005, Jaya Kumar <jayalk@intworks.biz>
*
* 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 driver was written to be used with the Arc LCD board. Arc uses a
* set of KS108 chips that control individual 64x64 LCD matrices. The board
* can be paneled in a variety of setups such as 2x1=128x64, 4x4=256x256 and
* so on. The interface between the board and the host is TTL based GPIO. The
* GPIO requirements are 8 writable data lines and 4+n lines for control. On a
* GPIO-less system, the board can be tested by connecting the respective sigs
* up to a parallel port connector. The driver requires the IO addresses for
* data and control GPIO at load time. It is unable to probe for the
* existence of the LCD so it must be told at load time whether it should
* be enabled or not.
*
* Todo:
* - testing with 4x4
* - testing with interrupt hw
*
* General notes:
* - User must set tuhold. It's in microseconds. According to the 108 spec,
* the hold time is supposed to be at least 1 microsecond.
* - User must set num_cols=x num_rows=y, eg: x=2 means 128
* - User must set arcfb_enable=1 to enable it
* - User must set dio_addr=0xIOADDR cio_addr=0xIOADDR
*
*/
#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/arcfb.h>
#include <linux/platform_device.h>
#include <linux/uaccess.h>
#define floor8(a) (a&(~0x07))
#define floorXres(a,xres) (a&(~(xres - 1)))
#define iceil8(a) (((int)((a+7)/8))*8)
#define ceil64(a) (a|0x3F)
#define ceilXres(a,xres) (a|(xres - 1))
/* ks108 chipset specific defines and code */
#define KS_SET_DPY_START_LINE 0xC0
#define KS_SET_PAGE_NUM 0xB8
#define KS_SET_X 0x40
#define KS_CEHI 0x01
#define KS_CELO 0x00
#define KS_SEL_CMD 0x08
#define KS_SEL_DATA 0x00
#define KS_DPY_ON 0x3F
#define KS_DPY_OFF 0x3E
#define KS_INTACK 0x40
#define KS_CLRINT 0x02
struct arcfb_par {
unsigned long dio_addr;
unsigned long cio_addr;
unsigned long c2io_addr;
atomic_t ref_count;
unsigned char cslut[9];
struct fb_info *info;
unsigned int irq;
spinlock_t lock;
};
static struct fb_fix_screeninfo arcfb_fix __devinitdata = {
.id = "arcfb",
.type = FB_TYPE_PACKED_PIXELS,
.visual = FB_VISUAL_MONO01,
.xpanstep = 0,
.ypanstep = 1,
.ywrapstep = 0,
.accel = FB_ACCEL_NONE,
};
static struct fb_var_screeninfo arcfb_var __devinitdata = {
.xres = 128,
.yres = 64,
.xres_virtual = 128,
.yres_virtual = 64,
.bits_per_pixel = 1,
.nonstd = 1,
};
static unsigned long num_cols;
static unsigned long num_rows;
static unsigned long dio_addr;
static unsigned long cio_addr;
static unsigned long c2io_addr;
static unsigned long splashval;
static unsigned long tuhold;
static unsigned int nosplash;
static unsigned int arcfb_enable;
static unsigned int irq;
static DECLARE_WAIT_QUEUE_HEAD(arcfb_waitq);
static void ks108_writeb_ctl(struct arcfb_par *par,
unsigned int chipindex, unsigned char value)
{
unsigned char chipselval = par->cslut[chipindex];
outb(chipselval|KS_CEHI|KS_SEL_CMD, par->cio_addr);
outb(value, par->dio_addr);
udelay(tuhold);
outb(chipselval|KS_CELO|KS_SEL_CMD, par->cio_addr);
}
static void ks108_writeb_mainctl(struct arcfb_par *par, unsigned char value)
{
outb(value, par->cio_addr);
udelay(tuhold);
}
static unsigned char ks108_readb_ctl2(struct arcfb_par *par)
{
return inb(par->c2io_addr);
}
static void ks108_writeb_data(struct arcfb_par *par,
unsigned int chipindex, unsigned char value)
{
unsigned char chipselval = par->cslut[chipindex];
outb(chipselval|KS_CEHI|KS_SEL_DATA, par->cio_addr);
outb(value, par->dio_addr);
udelay(tuhold);
outb(chipselval|KS_CELO|KS_SEL_DATA, par->cio_addr);
}
static void ks108_set_start_line(struct arcfb_par *par,
unsigned int chipindex, unsigned char y)
{
ks108_writeb_ctl(par, chipindex, KS_SET_DPY_START_LINE|y);
}
static void ks108_set_yaddr(struct arcfb_par *par,
unsigned int chipindex, unsigned char y)
{
ks108_writeb_ctl(par, chipindex, KS_SET_PAGE_NUM|y);
}
static void ks108_set_xaddr(struct arcfb_par *par,
unsigned int chipindex, unsigned char x)
{
ks108_writeb_ctl(par, chipindex, KS_SET_X|x);
}
static void ks108_clear_lcd(struct arcfb_par *par, unsigned int chipindex)
{
int i,j;
for (i = 0; i <= 8; i++) {
ks108_set_yaddr(par, chipindex, i);
ks108_set_xaddr(par, chipindex, 0);
for (j = 0; j < 64; j++) {
ks108_writeb_data(par, chipindex,
(unsigned char) splashval);
}
}
}
/* main arcfb functions */
static int arcfb_open(struct fb_info *info, int user)
{
struct arcfb_par *par = info->par;
atomic_inc(&par->ref_count);
return 0;
}
static int arcfb_release(struct fb_info *info, int user)
{
struct arcfb_par *par = info->par;
int count = atomic_read(&par->ref_count);
if (!count)
return -EINVAL;
atomic_dec(&par->ref_count);
return 0;
}
static int arcfb_pan_display(struct fb_var_screeninfo *var,
struct fb_info *info)
{
int i;
struct arcfb_par *par = info->par;
if ((var->vmode & FB_VMODE_YWRAP) && (var->yoffset < 64)
&& (info->var.yres <= 64)) {
for (i = 0; i < num_cols; i++) {
ks108_set_start_line(par, i, var->yoffset);
}
info->var.yoffset = var->yoffset;
return 0;
}
return -EINVAL;
}
static irqreturn_t arcfb_interrupt(int vec, void *dev_instance)
{
struct fb_info *info = dev_instance;
unsigned char ctl2status;
struct arcfb_par *par = info->par;
ctl2status = ks108_readb_ctl2(par);
if (!(ctl2status & KS_INTACK)) /* not arc generated interrupt */
return IRQ_NONE;
ks108_writeb_mainctl(par, KS_CLRINT);
spin_lock(&par->lock);
if (waitqueue_active(&arcfb_waitq)) {
wake_up(&arcfb_waitq);
}
spin_unlock(&par->lock);
return IRQ_HANDLED;
}
/*
* here we handle a specific page on the lcd. the complexity comes from
* the fact that the fb is laidout in 8xX vertical columns. we extract
* each write of 8 vertical pixels. then we shift out as we move along
* X. That's what rightshift does. bitmask selects the desired input bit.
*/
static void arcfb_lcd_update_page(struct arcfb_par *par, unsigned int upper,
unsigned int left, unsigned int right, unsigned int distance)
{
unsigned char *src;
unsigned int xindex, yindex, chipindex, linesize;
int i;
unsigned char val;
unsigned char bitmask, rightshift;
xindex = left >> 6;
yindex = upper >> 6;
chipindex = (xindex + (yindex*num_cols));
ks108_set_yaddr(par, chipindex, upper/8);
linesize = par->info->var.xres/8;
src = (unsigned char __force *) par->info->screen_base + (left/8) +
(upper * linesize);
ks108_set_xaddr(par, chipindex, left);
bitmask=1;
rightshift=0;
while (left <= right) {
val = 0;
for (i = 0; i < 8; i++) {
if ( i > rightshift) {
val |= (*(src + (i*linesize)) & bitmask)
<< (i - rightshift);
} else {
val |= (*(src + (i*linesize)) & bitmask)
>> (rightshift - i);
}
}
ks108_writeb_data(par, chipindex, val);
left++;
if (bitmask == 0x80) {
bitmask = 1;
src++;
rightshift=0;
} else {
bitmask <<= 1;
rightshift++;
}
}
}
/*
* here we handle the entire vertical page of the update. we write across
* lcd chips. update_page uses the upper/left values to decide which
* chip to select for the right. upper is needed for setting the page
* desired for the write.
*/
static void arcfb_lcd_update_vert(struct arcfb_par *par, unsigned int top,
unsigned int bottom, unsigned int left, unsigned int right)
{
unsigned int distance, upper, lower;
distance = (bottom - top) + 1;
upper = top;
lower = top + 7;
while (distance > 0) {
distance -= 8;
arcfb_lcd_update_page(par, upper, left, right, 8);
upper = lower + 1;
lower = upper + 7;
}
}
/*
* here we handle horizontal blocks for the update. update_vert will
* handle spaning multiple pages. we break out each horizontal
* block in to individual blocks no taller than 64 pixels.
*/
static void arcfb_lcd_update_horiz(struct arcfb_par *par, unsigned int left,
unsigned int right, unsigned int top, unsigned int h)
{
unsigned int distance, upper, lower;
distance = h;
upper = floor8(top);
lower = min(upper + distance - 1, ceil64(upper));
while (distance > 0) {
distance -= ((lower - upper) + 1 );
arcfb_lcd_update_vert(par, upper, lower, left, right);
upper = lower + 1;
lower = min(upper + distance - 1, ceil64(upper));
}
}
/*
* here we start the process of spliting out the fb update into
* individual blocks of pixels. we end up spliting into 64x64 blocks
* and finally down to 64x8 pages.
*/
static void arcfb_lcd_update(struct arcfb_par *par, unsigned int dx,
unsigned int dy, unsigned int w, unsigned int h)
{
unsigned int left, right, distance, y;
/* align the request first */
y = floor8(dy);
h += dy - y;
h = iceil8(h);
distance = w;
left = dx;
right = min(left + w - 1, ceil64(left));
while (distance > 0) {
arcfb_lcd_update_horiz(par, left, right, y, h);
distance -= ((right - left) + 1);
left = right + 1;
right = min(left + distance - 1, ceil64(left));
}
}
static void arcfb_fillrect(struct fb_info *info,
const struct fb_fillrect *rect)
{
struct arcfb_par *par = info->par;
sys_fillrect(info, rect);
/* update the physical lcd */
arcfb_lcd_update(par, rect->dx, rect->dy, rect->width, rect->height);
}
static void arcfb_copyarea(struct fb_info *info,
const struct fb_copyarea *area)
{
struct arcfb_par *par = info->par;
sys_copyarea(info, area);
/* update the physical lcd */
arcfb_lcd_update(par, area->dx, area->dy, area->width, area->height);
}
static void arcfb_imageblit(struct fb_info *info, const struct fb_image *image)
{
struct arcfb_par *par = info->par;
sys_imageblit(info, image);
/* update the physical lcd */
arcfb_lcd_update(par, image->dx, image->dy, image->width,
image->height);
}
static int arcfb_ioctl(struct fb_info *info,
unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
struct arcfb_par *par = info->par;
unsigned long flags;
switch (cmd) {
case FBIO_WAITEVENT:
{
DEFINE_WAIT(wait);
/* illegal to wait on arc if no irq will occur */
if (!par->irq)
return -EINVAL;
/* wait until the Arc has generated an interrupt
* which will wake us up */
spin_lock_irqsave(&par->lock, flags);
prepare_to_wait(&arcfb_waitq, &wait,
TASK_INTERRUPTIBLE);
spin_unlock_irqrestore(&par->lock, flags);
schedule();
finish_wait(&arcfb_waitq, &wait);
}
case FBIO_GETCONTROL2:
{
unsigned char ctl2;
ctl2 = ks108_readb_ctl2(info->par);
if (copy_to_user(argp, &ctl2, sizeof(ctl2)))
return -EFAULT;
return 0;
}
default:
return -EINVAL;
}
}
/*
* this is the access path from userspace. they can seek and write to
* the fb. it's inefficient for them to do anything less than 64*8
* writes since we update the lcd in each write() anyway.
*/
static ssize_t arcfb_write(struct fb_info *info, const char __user *buf,
size_t count, loff_t *ppos)
{
/* modded from epson 1355 */
unsigned long p;
int err=-EINVAL;
unsigned int fbmemlength,x,y,w,h, bitppos, startpos, endpos, bitcount;
struct arcfb_par *par;
unsigned int xres;
p = *ppos;
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 = (char __force *)info->screen_base;
count -= copy_from_user(base_addr + p, buf, count);
*ppos += count;
err = -EFAULT;
}
bitppos = p*8;
startpos = floorXres(bitppos, xres);
endpos = ceilXres((bitppos + (count*8)), xres);
bitcount = endpos - startpos;
x = startpos % xres;
y = startpos / xres;
w = xres;
h = bitcount / xres;
arcfb_lcd_update(par, x, y, w, h);
if (count)
return count;
return err;
}
static struct fb_ops arcfb_ops = {
.owner = THIS_MODULE,
.fb_open = arcfb_open,
.fb_read = fb_sys_read,
.fb_write = arcfb_write,
.fb_release = arcfb_release,
.fb_pan_display = arcfb_pan_display,
.fb_fillrect = arcfb_fillrect,
.fb_copyarea = arcfb_copyarea,
.fb_imageblit = arcfb_imageblit,
.fb_ioctl = arcfb_ioctl,
};
static int __devinit arcfb_probe(struct platform_device *dev)
{
struct fb_info *info;
int retval = -ENOMEM;
int videomemorysize;
unsigned char *videomemory;
struct arcfb_par *par;
int i;
videomemorysize = (((64*64)*num_cols)*num_rows)/8;
/* We need a flat backing store for the Arc's
less-flat actual paged framebuffer */
videomemory = vzalloc(videomemorysize);
if (!videomemory)
return retval;
info = framebuffer_alloc(sizeof(struct arcfb_par), &dev->dev);
if (!info)
goto err;
info->screen_base = (char __iomem *)videomemory;
info->fbops = &arcfb_ops;
info->var = arcfb_var;
info->fix = arcfb_fix;
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;
par->cslut[0] = 0x00;
par->cslut[1] = 0x06;
info->flags = FBINFO_FLAG_DEFAULT;
spin_lock_init(&par->lock);
retval = register_framebuffer(info);
if (retval < 0)
goto err1;
platform_set_drvdata(dev, info);
if (irq) {
par->irq = irq;
if (request_irq(par->irq, &arcfb_interrupt, IRQF_SHARED,
"arcfb", info)) {
printk(KERN_INFO
"arcfb: Failed req IRQ %d\n", par->irq);
goto err1;
}
}
printk(KERN_INFO
"fb%d: Arc frame buffer device, using %dK of video memory\n",
info->node, videomemorysize >> 10);
/* this inits the lcd but doesn't clear dirty pixels */
for (i = 0; i < num_cols * num_rows; i++) {
ks108_writeb_ctl(par, i, KS_DPY_OFF);
ks108_set_start_line(par, i, 0);
ks108_set_yaddr(par, i, 0);
ks108_set_xaddr(par, i, 0);
ks108_writeb_ctl(par, i, KS_DPY_ON);
}
/* if we were told to splash the screen, we just clear it */
if (!nosplash) {
for (i = 0; i < num_cols * num_rows; i++) {
printk(KERN_INFO "fb%d: splashing lcd %d\n",
info->node, i);
ks108_set_start_line(par, i, 0);
ks108_clear_lcd(par, i);
}
}
return 0;
err1:
framebuffer_release(info);
err:
vfree(videomemory);
return retval;
}
static int __devexit arcfb_remove(struct platform_device *dev)
{
struct fb_info *info = platform_get_drvdata(dev);
if (info) {
unregister_framebuffer(info);
vfree((void __force *)info->screen_base);
framebuffer_release(info);
}
return 0;
}
static struct platform_driver arcfb_driver = {
.probe = arcfb_probe,
.remove = __devexit_p(arcfb_remove),
.driver = {
.name = "arcfb",
},
};
static struct platform_device *arcfb_device;
static int __init arcfb_init(void)
{
int ret;
if (!arcfb_enable)
return -ENXIO;
ret = platform_driver_register(&arcfb_driver);
if (!ret) {
arcfb_device = platform_device_alloc("arcfb", 0);
if (arcfb_device) {
ret = platform_device_add(arcfb_device);
} else {
ret = -ENOMEM;
}
if (ret) {
platform_device_put(arcfb_device);
platform_driver_unregister(&arcfb_driver);
}
}
return ret;
}
static void __exit arcfb_exit(void)
{
platform_device_unregister(arcfb_device);
platform_driver_unregister(&arcfb_driver);
}
module_param(num_cols, ulong, 0);
MODULE_PARM_DESC(num_cols, "Num horiz panels, eg: 2 = 128 bit wide");
module_param(num_rows, ulong, 0);
MODULE_PARM_DESC(num_rows, "Num vert panels, eg: 1 = 64 bit high");
module_param(nosplash, uint, 0);
MODULE_PARM_DESC(nosplash, "Disable doing the splash screen");
module_param(arcfb_enable, uint, 0);
MODULE_PARM_DESC(arcfb_enable, "Enable communication with Arc 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: 0xFF is black, 0x00 is green");
module_param(tuhold, ulong, 0);
MODULE_PARM_DESC(tuhold, "Time to hold between strobing data to Arc board");
module_param(irq, uint, 0);
MODULE_PARM_DESC(irq, "IRQ for the Arc board");
module_init(arcfb_init);
module_exit(arcfb_exit);
MODULE_DESCRIPTION("fbdev driver for Arc monochrome LCD board");
MODULE_AUTHOR("Jaya Kumar");
MODULE_LICENSE("GPL");