2 * linux/drivers/video/clps711xfb.c
4 * Copyright (C) 2000-2001 Deep Blue Solutions Ltd.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 * Framebuffer driver for the CLPS7111 and EP7212 processors.
23 #include <linux/module.h>
24 #include <linux/kernel.h>
25 #include <linux/slab.h>
27 #include <linux/init.h>
28 #include <linux/delay.h>
30 #include <mach/hardware.h>
31 #include <asm/mach-types.h>
32 #include <linux/uaccess.h>
36 #define CMAP_MAX_SIZE 16
39 * LCD AC Prescale. This comes from the LCD panel manufacturers specifications.
40 * This determines how many clocks + 1 of CL1 before the M signal toggles.
41 * The number of lines on the display must not be divisible by this number.
43 static unsigned int lcd_ac_prescale
= 13;
46 * Set a single color register. Return != 0 for invalid regno.
49 clps7111fb_setcolreg(u_int regno
, u_int red
, u_int green
, u_int blue
,
50 u_int transp
, struct fb_info
*info
)
52 unsigned int level
, mask
, shift
, pal
;
54 if (regno
>= (1 << info
->var
.bits_per_pixel
))
57 /* gray = 0.30*R + 0.58*G + 0.11*B */
58 level
= (red
* 77 + green
* 151 + blue
* 28) >> 20;
61 * On an LCD, a high value is dark, while a low value is light.
62 * So we invert the level.
64 * This isn't true on all machines, so we only do it on EDB7211.
67 if (machine_is_edb7211()) {
71 shift
= 4 * (regno
& 7);
76 regno
= regno
< 8 ? PALLSW
: PALMSW
;
78 pal
= clps_readl(regno
);
79 pal
= (pal
& ~mask
) | level
;
80 clps_writel(pal
, regno
);
86 * Validate the purposed mode.
89 clps7111fb_check_var(struct fb_var_screeninfo
*var
, struct fb_info
*info
)
91 var
->transp
.msb_right
= 0;
92 var
->transp
.offset
= 0;
93 var
->transp
.length
= 0;
94 var
->red
.msb_right
= 0;
96 var
->red
.length
= var
->bits_per_pixel
;
97 var
->green
= var
->red
;
100 if (var
->bits_per_pixel
> 4)
107 * Set the hardware state.
110 clps7111fb_set_par(struct fb_info
*info
)
112 unsigned int lcdcon
, syscon
, pixclock
;
114 switch (info
->var
.bits_per_pixel
) {
116 info
->fix
.visual
= FB_VISUAL_MONO01
;
119 info
->fix
.visual
= FB_VISUAL_PSEUDOCOLOR
;
122 info
->fix
.visual
= FB_VISUAL_PSEUDOCOLOR
;
126 info
->fix
.line_length
= info
->var
.xres_virtual
* info
->var
.bits_per_pixel
/ 8;
128 lcdcon
= (info
->var
.xres_virtual
* info
->var
.yres_virtual
* info
->var
.bits_per_pixel
) / 128 - 1;
129 lcdcon
|= ((info
->var
.xres_virtual
/ 16) - 1) << 13;
130 lcdcon
|= lcd_ac_prescale
<< 25;
133 * Calculate pixel prescale value from the pixclock. This is:
134 * 36.864MHz / pixclock_mhz - 1.
135 * However, pixclock is in picoseconds, so this ends up being:
136 * 36864000 * pixclock_ps / 10^12 - 1
137 * and this will overflow the 32-bit math. We perform this as
138 * (9 * 4096000 == 36864000):
139 * pixclock_ps * 9 * (4096000 / 10^12) - 1
141 pixclock
= 9 * info
->var
.pixclock
/ 244140 - 1;
142 lcdcon
|= pixclock
<< 19;
144 if (info
->var
.bits_per_pixel
== 4)
145 lcdcon
|= LCDCON_GSMD
;
146 if (info
->var
.bits_per_pixel
>= 2)
147 lcdcon
|= LCDCON_GSEN
;
150 * LCDCON must only be changed while the LCD is disabled
152 syscon
= clps_readl(SYSCON1
);
153 clps_writel(syscon
& ~SYSCON1_LCDEN
, SYSCON1
);
154 clps_writel(lcdcon
, LCDCON
);
155 clps_writel(syscon
| SYSCON1_LCDEN
, SYSCON1
);
159 static int clps7111fb_blank(int blank
, struct fb_info
*info
)
161 /* Enable/Disable LCD controller. */
163 clps_writel(clps_readl(SYSCON1
) & ~SYSCON1_LCDEN
, SYSCON1
);
165 clps_writel(clps_readl(SYSCON1
) | SYSCON1_LCDEN
, SYSCON1
);
170 static struct fb_ops clps7111fb_ops
= {
171 .owner
= THIS_MODULE
,
172 .fb_check_var
= clps7111fb_check_var
,
173 .fb_set_par
= clps7111fb_set_par
,
174 .fb_setcolreg
= clps7111fb_setcolreg
,
175 .fb_blank
= clps7111fb_blank
,
176 .fb_fillrect
= cfb_fillrect
,
177 .fb_copyarea
= cfb_copyarea
,
178 .fb_imageblit
= cfb_imageblit
,
181 static void clps711x_guess_lcd_params(struct fb_info
*info
)
183 unsigned int lcdcon
, syscon
, size
;
184 unsigned long phys_base
= PAGE_OFFSET
;
185 void *virt_base
= (void *)PAGE_OFFSET
;
187 info
->var
.xres_virtual
= 640;
188 info
->var
.yres_virtual
= 240;
189 info
->var
.bits_per_pixel
= 4;
190 info
->var
.activate
= FB_ACTIVATE_NOW
;
191 info
->var
.height
= -1;
192 info
->var
.width
= -1;
193 info
->var
.pixclock
= 93006; /* 10.752MHz pixel clock */
196 * If the LCD controller is already running, decode the values
197 * in LCDCON to xres/yres/bpp/pixclock/acprescale
199 syscon
= clps_readl(SYSCON1
);
200 if (syscon
& SYSCON1_LCDEN
) {
201 lcdcon
= clps_readl(LCDCON
);
204 * Decode GSMD and GSEN bits to bits per pixel
206 switch (lcdcon
& (LCDCON_GSMD
| LCDCON_GSEN
)) {
207 case LCDCON_GSMD
| LCDCON_GSEN
:
208 info
->var
.bits_per_pixel
= 4;
212 info
->var
.bits_per_pixel
= 2;
216 info
->var
.bits_per_pixel
= 1;
223 info
->var
.xres_virtual
= (((lcdcon
>> 13) & 0x3f) + 1) * 16;
224 info
->var
.yres_virtual
= (((lcdcon
& 0x1fff) + 1) * 128) /
225 (info
->var
.xres_virtual
*
226 info
->var
.bits_per_pixel
);
231 info
->var
.pixclock
= (((lcdcon
>> 19) & 0x3f) + 1) * 244140 / 9;
236 lcd_ac_prescale
= (lcdcon
>> 25) & 0x1f;
239 info
->var
.xres
= info
->var
.xres_virtual
;
240 info
->var
.yres
= info
->var
.yres_virtual
;
241 info
->var
.grayscale
= info
->var
.bits_per_pixel
> 1;
243 size
= info
->var
.xres
* info
->var
.yres
* info
->var
.bits_per_pixel
/ 8;
246 * Might be worth checking to see if we can use the on-board
247 * RAM if size here...
248 * CLPS7110 - no on-board SRAM
249 * EP7212 - 38400 bytes
252 printk(KERN_INFO
"CLPS711xFB: could use on-board SRAM?\n");
255 if ((syscon
& SYSCON1_LCDEN
) == 0) {
257 * The display isn't running. Ensure that
258 * the display memory is empty.
260 memset(virt_base
, 0, size
);
263 info
->screen_base
= virt_base
;
264 info
->fix
.smem_start
= phys_base
;
265 info
->fix
.smem_len
= PAGE_ALIGN(size
);
266 info
->fix
.type
= FB_TYPE_PACKED_PIXELS
;
269 static int clps711x_fb_probe(struct platform_device
*pdev
)
273 if (fb_get_options("clps711xfb", NULL
))
276 cfb
= kzalloc(sizeof(*cfb
), GFP_KERNEL
);
280 strcpy(cfb
->fix
.id
, "clps711x");
282 cfb
->fbops
= &clps7111fb_ops
;
283 cfb
->flags
= FBINFO_DEFAULT
;
285 clps711x_guess_lcd_params(cfb
);
287 fb_alloc_cmap(&cfb
->cmap
, CMAP_MAX_SIZE
, 0);
289 err
= register_framebuffer(cfb
);
294 static int clps711x_fb_remove(struct platform_device
*pdev
)
296 unregister_framebuffer(cfb
);
302 static struct platform_driver clps711x_fb_driver
= {
304 .name
= "video-clps711x",
305 .owner
= THIS_MODULE
,
307 .probe
= clps711x_fb_probe
,
308 .remove
= clps711x_fb_remove
,
310 module_platform_driver(clps711x_fb_driver
);
312 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
313 MODULE_DESCRIPTION("CLPS711X framebuffer driver");
314 MODULE_LICENSE("GPL");