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");