- 根目录:
- drivers
- video
- clps711xfb.c
/*
* linux/drivers/video/clps711xfb.c
*
* Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Framebuffer driver for the CLPS7111 and EP7212 processors.
*/
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <mach/hardware.h>
#include <asm/mach-types.h>
#include <linux/uaccess.h>
struct fb_info *cfb;
#define CMAP_MAX_SIZE 16
/*
* LCD AC Prescale. This comes from the LCD panel manufacturers specifications.
* This determines how many clocks + 1 of CL1 before the M signal toggles.
* The number of lines on the display must not be divisible by this number.
*/
static unsigned int lcd_ac_prescale = 13;
/*
* Set a single color register. Return != 0 for invalid regno.
*/
static int
clps7111fb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
u_int transp, struct fb_info *info)
{
unsigned int level, mask, shift, pal;
if (regno >= (1 << info->var.bits_per_pixel))
return 1;
/* gray = 0.30*R + 0.58*G + 0.11*B */
level = (red * 77 + green * 151 + blue * 28) >> 20;
/*
* On an LCD, a high value is dark, while a low value is light.
* So we invert the level.
*
* This isn't true on all machines, so we only do it on EDB7211.
* --rmk
*/
if (machine_is_edb7211()) {
level = 15 - level;
}
shift = 4 * (regno & 7);
level <<= shift;
mask = 15 << shift;
level &= mask;
regno = regno < 8 ? PALLSW : PALMSW;
pal = clps_readl(regno);
pal = (pal & ~mask) | level;
clps_writel(pal, regno);
return 0;
}
/*
* Validate the purposed mode.
*/
static int
clps7111fb_check_var(struct fb_var_screeninfo *var, struct fb_info *info)
{
var->transp.msb_right = 0;
var->transp.offset = 0;
var->transp.length = 0;
var->red.msb_right = 0;
var->red.offset = 0;
var->red.length = var->bits_per_pixel;
var->green = var->red;
var->blue = var->red;
if (var->bits_per_pixel > 4)
return -EINVAL;
return 0;
}
/*
* Set the hardware state.
*/
static int
clps7111fb_set_par(struct fb_info *info)
{
unsigned int lcdcon, syscon, pixclock;
switch (info->var.bits_per_pixel) {
case 1:
info->fix.visual = FB_VISUAL_MONO01;
break;
case 2:
info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
break;
case 4:
info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
break;
}
info->fix.line_length = info->var.xres_virtual * info->var.bits_per_pixel / 8;
lcdcon = (info->var.xres_virtual * info->var.yres_virtual * info->var.bits_per_pixel) / 128 - 1;
lcdcon |= ((info->var.xres_virtual / 16) - 1) << 13;
lcdcon |= lcd_ac_prescale << 25;
/*
* Calculate pixel prescale value from the pixclock. This is:
* 36.864MHz / pixclock_mhz - 1.
* However, pixclock is in picoseconds, so this ends up being:
* 36864000 * pixclock_ps / 10^12 - 1
* and this will overflow the 32-bit math. We perform this as
* (9 * 4096000 == 36864000):
* pixclock_ps * 9 * (4096000 / 10^12) - 1
*/
pixclock = 9 * info->var.pixclock / 244140 - 1;
lcdcon |= pixclock << 19;
if (info->var.bits_per_pixel == 4)
lcdcon |= LCDCON_GSMD;
if (info->var.bits_per_pixel >= 2)
lcdcon |= LCDCON_GSEN;
/*
* LCDCON must only be changed while the LCD is disabled
*/
syscon = clps_readl(SYSCON1);
clps_writel(syscon & ~SYSCON1_LCDEN, SYSCON1);
clps_writel(lcdcon, LCDCON);
clps_writel(syscon | SYSCON1_LCDEN, SYSCON1);
return 0;
}
static int clps7111fb_blank(int blank, struct fb_info *info)
{
/* Enable/Disable LCD controller. */
if (blank)
clps_writel(clps_readl(SYSCON1) & ~SYSCON1_LCDEN, SYSCON1);
else
clps_writel(clps_readl(SYSCON1) | SYSCON1_LCDEN, SYSCON1);
return 0;
}
static struct fb_ops clps7111fb_ops = {
.owner = THIS_MODULE,
.fb_check_var = clps7111fb_check_var,
.fb_set_par = clps7111fb_set_par,
.fb_setcolreg = clps7111fb_setcolreg,
.fb_blank = clps7111fb_blank,
.fb_fillrect = cfb_fillrect,
.fb_copyarea = cfb_copyarea,
.fb_imageblit = cfb_imageblit,
};
static void clps711x_guess_lcd_params(struct fb_info *info)
{
unsigned int lcdcon, syscon, size;
unsigned long phys_base = PAGE_OFFSET;
void *virt_base = (void *)PAGE_OFFSET;
info->var.xres_virtual = 640;
info->var.yres_virtual = 240;
info->var.bits_per_pixel = 4;
info->var.activate = FB_ACTIVATE_NOW;
info->var.height = -1;
info->var.width = -1;
info->var.pixclock = 93006; /* 10.752MHz pixel clock */
/*
* If the LCD controller is already running, decode the values
* in LCDCON to xres/yres/bpp/pixclock/acprescale
*/
syscon = clps_readl(SYSCON1);
if (syscon & SYSCON1_LCDEN) {
lcdcon = clps_readl(LCDCON);
/*
* Decode GSMD and GSEN bits to bits per pixel
*/
switch (lcdcon & (LCDCON_GSMD | LCDCON_GSEN)) {
case LCDCON_GSMD | LCDCON_GSEN:
info->var.bits_per_pixel = 4;
break;
case LCDCON_GSEN:
info->var.bits_per_pixel = 2;
break;
default:
info->var.bits_per_pixel = 1;
break;
}
/*
* Decode xres/yres
*/
info->var.xres_virtual = (((lcdcon >> 13) & 0x3f) + 1) * 16;
info->var.yres_virtual = (((lcdcon & 0x1fff) + 1) * 128) /
(info->var.xres_virtual *
info->var.bits_per_pixel);
/*
* Calculate pixclock
*/
info->var.pixclock = (((lcdcon >> 19) & 0x3f) + 1) * 244140 / 9;
/*
* Grab AC prescale
*/
lcd_ac_prescale = (lcdcon >> 25) & 0x1f;
}
info->var.xres = info->var.xres_virtual;
info->var.yres = info->var.yres_virtual;
info->var.grayscale = info->var.bits_per_pixel > 1;
size = info->var.xres * info->var.yres * info->var.bits_per_pixel / 8;
/*
* Might be worth checking to see if we can use the on-board
* RAM if size here...
* CLPS7110 - no on-board SRAM
* EP7212 - 38400 bytes
*/
if (size <= 38400) {
printk(KERN_INFO "CLPS711xFB: could use on-board SRAM?\n");
}
if ((syscon & SYSCON1_LCDEN) == 0) {
/*
* The display isn't running. Ensure that
* the display memory is empty.
*/
memset(virt_base, 0, size);
}
info->screen_base = virt_base;
info->fix.smem_start = phys_base;
info->fix.smem_len = PAGE_ALIGN(size);
info->fix.type = FB_TYPE_PACKED_PIXELS;
}
static int clps711x_fb_probe(struct platform_device *pdev)
{
int err = -ENOMEM;
if (fb_get_options("clps711xfb", NULL))
return -ENODEV;
cfb = kzalloc(sizeof(*cfb), GFP_KERNEL);
if (!cfb)
goto out;
strcpy(cfb->fix.id, "clps711x");
cfb->fbops = &clps7111fb_ops;
cfb->flags = FBINFO_DEFAULT;
clps711x_guess_lcd_params(cfb);
fb_alloc_cmap(&cfb->cmap, CMAP_MAX_SIZE, 0);
err = register_framebuffer(cfb);
out: return err;
}
static int clps711x_fb_remove(struct platform_device *pdev)
{
unregister_framebuffer(cfb);
kfree(cfb);
return 0;
}
static struct platform_driver clps711x_fb_driver = {
.driver = {
.name = "video-clps711x",
.owner = THIS_MODULE,
},
.probe = clps711x_fb_probe,
.remove = clps711x_fb_remove,
};
module_platform_driver(clps711x_fb_driver);
MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
MODULE_DESCRIPTION("CLPS711X framebuffer driver");
MODULE_LICENSE("GPL");