/*
* xilinxfb.c
*
* Xilinx TFT LCD frame buffer driver
*
* Author: MontaVista Software, Inc.
* source@mvista.com
*
* 2002-2007 (c) MontaVista Software, Inc. This file is licensed under the
* terms of the GNU General Public License version 2. This program is licensed
* "as is" without any warranty of any kind, whether express or implied.
*/
/*
* This driver was based on au1100fb.c by MontaVista rewritten for 2.6
* by Embedded Alley Solutions <source@embeddedalley.com>, which in turn
* was based on skeletonfb.c, Skeleton for a frame buffer device by
* Geert Uytterhoeven.
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/version.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/mm.h>
#include <linux/fb.h>
#include <linux/init.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
#include <asm/io.h>
#include <linux/xilinxfb.h>
#define DRIVER_NAME "xilinxfb"
#define DRIVER_DESCRIPTION "Xilinx TFT LCD frame buffer driver"
/*
* Xilinx calls it "PLB TFT LCD Controller" though it can also be used for
* the VGA port on the Xilinx ML40x board. This is a hardware display controller
* for a 640x480 resolution TFT or VGA screen.
*
* The interface to the framebuffer is nice and simple. There are two
* control registers. The first tells the LCD interface where in memory
* the frame buffer is (only the 11 most significant bits are used, so
* don't start thinking about scrolling). The second allows the LCD to
* be turned on or off as well as rotated 180 degrees.
*/
#define NUM_REGS 2
#define REG_FB_ADDR 0
#define REG_CTRL 1
#define REG_CTRL_ENABLE 0x0001
#define REG_CTRL_ROTATE 0x0002
/*
* The hardware only handles a single mode: 640x480 24 bit true
* color. Each pixel gets a word (32 bits) of memory. Within each word,
* the 8 most significant bits are ignored, the next 8 bits are the red
* level, the next 8 bits are the green level and the 8 least
* significant bits are the blue level. Each row of the LCD uses 1024
* words, but only the first 640 pixels are displayed with the other 384
* words being ignored. There are 480 rows.
*/
#define BYTES_PER_PIXEL 4
#define BITS_PER_PIXEL (BYTES_PER_PIXEL * 8)
#define XRES 640
#define YRES 480
#define XRES_VIRTUAL 1024
#define YRES_VIRTUAL YRES
#define LINE_LENGTH (XRES_VIRTUAL * BYTES_PER_PIXEL)
#define FB_SIZE (YRES_VIRTUAL * LINE_LENGTH)
#define RED_SHIFT 16
#define GREEN_SHIFT 8
#define BLUE_SHIFT 0
#define PALETTE_ENTRIES_NO 16 /* passed to fb_alloc_cmap() */
/*
* Here are the default fb_fix_screeninfo and fb_var_screeninfo structures
*/
static struct fb_fix_screeninfo xilinx_fb_fix = {
.id = "Xilinx",
.type = FB_TYPE_PACKED_PIXELS,
.visual = FB_VISUAL_TRUECOLOR,
.smem_len = FB_SIZE,
.line_length = LINE_LENGTH,
.accel = FB_ACCEL_NONE
};
static struct fb_var_screeninfo xilinx_fb_var = {
.xres = XRES,
.yres = YRES,
.xres_virtual = XRES_VIRTUAL,
.yres_virtual = YRES_VIRTUAL,
.bits_per_pixel = BITS_PER_PIXEL,
.red = { RED_SHIFT, 8, 0 },
.green = { GREEN_SHIFT, 8, 0 },
.blue = { BLUE_SHIFT, 8, 0 },
.transp = { 0, 0, 0 },
.activate = FB_ACTIVATE_NOW
};
struct xilinxfb_drvdata {
struct fb_info info; /* FB driver info record */
u32 regs_phys; /* phys. address of the control registers */
u32 __iomem *regs; /* virt. address of the control registers */
unsigned char __iomem *fb_virt; /* virt. address of the frame buffer */
dma_addr_t fb_phys; /* phys. address of the frame buffer */
u32 reg_ctrl_default;
u32 pseudo_palette[PALETTE_ENTRIES_NO];
/* Fake palette of 16 colors */
};
#define to_xilinxfb_drvdata(_info) \
container_of(_info, struct xilinxfb_drvdata, info)
/*
* The LCD controller has DCR interface to its registers, but all
* the boards and configurations the driver has been tested with
* use opb2dcr bridge. So the registers are seen as memory mapped.
* This macro is to make it simple to add the direct DCR access
* when it's needed.
*/
#define xilinx_fb_out_be32(driverdata, offset, val) \
out_be32(driverdata->regs + offset, val)
static int
xilinx_fb_setcolreg(unsigned regno, unsigned red, unsigned green, unsigned blue,
unsigned transp, struct fb_info *fbi)
{
u32 *palette = fbi->pseudo_palette;
if (regno >= PALETTE_ENTRIES_NO)
return -EINVAL;
if (fbi->var.grayscale) {
/* Convert color to grayscale.
* grayscale = 0.30*R + 0.59*G + 0.11*B */
red = green = blue =
(red * 77 + green * 151 + blue * 28 + 127) >> 8;
}
/* fbi->fix.visual is always FB_VISUAL_TRUECOLOR */
/* We only handle 8 bits of each color. */
red >>= 8;
green >>= 8;
blue >>= 8;
palette[regno] = (red << RED_SHIFT) | (green << GREEN_SHIFT) |
(blue << BLUE_SHIFT);
return 0;
}
static int
xilinx_fb_blank(int blank_mode, struct fb_info *fbi)
{
struct xilinxfb_drvdata *drvdata = to_xilinxfb_drvdata(fbi);
switch (blank_mode) {
case FB_BLANK_UNBLANK:
/* turn on panel */
xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
break;
case FB_BLANK_NORMAL:
case FB_BLANK_VSYNC_SUSPEND:
case FB_BLANK_HSYNC_SUSPEND:
case FB_BLANK_POWERDOWN:
/* turn off panel */
xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
default:
break;
}
return 0; /* success */
}
static struct fb_ops xilinxfb_ops =
{
.owner = THIS_MODULE,
.fb_setcolreg = xilinx_fb_setcolreg,
.fb_blank = xilinx_fb_blank,
.fb_fillrect = cfb_fillrect,
.fb_copyarea = cfb_copyarea,
.fb_imageblit = cfb_imageblit,
};
/* ---------------------------------------------------------------------
* Bus independent setup/teardown
*/
static int xilinxfb_assign(struct device *dev, unsigned long physaddr,
int width_mm, int height_mm, int rotate)
{
struct xilinxfb_drvdata *drvdata;
int rc;
/* Allocate the driver data region */
drvdata = kzalloc(sizeof(*drvdata), GFP_KERNEL);
if (!drvdata) {
dev_err(dev, "Couldn't allocate device private record\n");
return -ENOMEM;
}
dev_set_drvdata(dev, drvdata);
/* Map the control registers in */
if (!request_mem_region(physaddr, 8, DRIVER_NAME)) {
dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
physaddr);
rc = -ENODEV;
goto err_region;
}
drvdata->regs_phys = physaddr;
drvdata->regs = ioremap(physaddr, 8);
if (!drvdata->regs) {
dev_err(dev, "Couldn't lock memory region at 0x%08lX\n",
physaddr);
rc = -ENODEV;
goto err_map;
}
/* Allocate the framebuffer memory */
drvdata->fb_virt = dma_alloc_coherent(dev, PAGE_ALIGN(FB_SIZE),
&drvdata->fb_phys, GFP_KERNEL);
if (!drvdata->fb_virt) {
dev_err(dev, "Could not allocate frame buffer memory\n");
rc = -ENOMEM;
goto err_fbmem;
}
/* Clear (turn to black) the framebuffer */
memset_io(drvdata->fb_virt, 0, FB_SIZE);
/* Tell the hardware where the frame buffer is */
xilinx_fb_out_be32(drvdata, REG_FB_ADDR, drvdata->fb_phys);
/* Turn on the display */
drvdata->reg_ctrl_default = REG_CTRL_ENABLE;
if (rotate)
drvdata->reg_ctrl_default |= REG_CTRL_ROTATE;
xilinx_fb_out_be32(drvdata, REG_CTRL, drvdata->reg_ctrl_default);
/* Fill struct fb_info */
drvdata->info.device = dev;
drvdata->info.screen_base = drvdata->fb_virt;
drvdata->info.fbops = &xilinxfb_ops;
drvdata->info.fix = xilinx_fb_fix;
drvdata->info.fix.smem_start = drvdata->fb_phys;
drvdata->info.pseudo_palette = drvdata->pseudo_palette;
drvdata->info.flags = FBINFO_DEFAULT;
drvdata->info.var = xilinx_fb_var;
xilinx_fb_var.height = height_mm;
xilinx_fb_var.width = width_mm;
/* Allocate a colour map */
rc = fb_alloc_cmap(&drvdata->info.cmap, PALETTE_ENTRIES_NO, 0);
if (rc) {
dev_err(dev, "Fail to allocate colormap (%d entries)\n",
PALETTE_ENTRIES_NO);
goto err_cmap;
}
/* Register new frame buffer */
rc = register_framebuffer(&drvdata->info);
if (rc) {
dev_err(dev, "Could not register frame buffer\n");
goto err_regfb;
}
/* Put a banner in the log (for DEBUG) */
dev_dbg(dev, "regs: phys=%lx, virt=%p\n", physaddr, drvdata->regs);
dev_dbg(dev, "fb: phys=%p, virt=%p, size=%x\n",
(void*)drvdata->fb_phys, drvdata->fb_virt, FB_SIZE);
return 0; /* success */
err_regfb:
fb_dealloc_cmap(&drvdata->info.cmap);
err_cmap:
dma_free_coherent(dev, PAGE_ALIGN(FB_SIZE), drvdata->fb_virt,
drvdata->fb_phys);
/* Turn off the display */
xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
err_fbmem:
iounmap(drvdata->regs);
err_map:
release_mem_region(physaddr, 8);
err_region:
kfree(drvdata);
dev_set_drvdata(dev, NULL);
return rc;
}
static int xilinxfb_release(struct device *dev)
{
struct xilinxfb_drvdata *drvdata = dev_get_drvdata(dev);
#if !defined(CONFIG_FRAMEBUFFER_CONSOLE) && defined(CONFIG_LOGO)
xilinx_fb_blank(VESA_POWERDOWN, &drvdata->info);
#endif
unregister_framebuffer(&drvdata->info);
fb_dealloc_cmap(&drvdata->info.cmap);
dma_free_coherent(dev, PAGE_ALIGN(FB_SIZE), drvdata->fb_virt,
drvdata->fb_phys);
/* Turn off the display */
xilinx_fb_out_be32(drvdata, REG_CTRL, 0);
iounmap(drvdata->regs);
release_mem_region(drvdata->regs_phys, 8);
kfree(drvdata);
dev_set_drvdata(dev, NULL);
return 0;
}
/* ---------------------------------------------------------------------
* Platform bus binding
*/
static int
xilinxfb_platform_probe(struct platform_device *pdev)
{
struct xilinxfb_platform_data *pdata;
struct resource *res;
int width_mm;
int height_mm;
int rotate;
pdata = pdev->dev.platform_data;
if (!pdata) {
dev_err(&pdev->dev, "Missing pdata structure\n");
return -ENODEV;
}
/* Find the registers address */
res = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (!res) {
dev_err(&pdev->dev, "Couldn't get registers resource\n");
return -ENODEV;
}
height_mm = pdata->screen_height_mm;
width_mm = pdata->screen_width_mm;
rotate = pdata->rotate_screen ? 1 : 0;
return xilinxfb_assign(&pdev->dev, res->start, width_mm, height_mm,
rotate);
}
static int
xilinxfb_platform_remove(struct platform_device *pdev)
{
return xilinxfb_release(&pdev->dev);
}
static struct platform_driver xilinxfb_platform_driver = {
.probe = xilinxfb_platform_probe,
.remove = xilinxfb_platform_remove,
.driver = {
.owner = THIS_MODULE,
.name = DRIVER_NAME,
},
};
static int __init
xilinxfb_init(void)
{
/*
* No kernel boot options used,
* so we just need to register the driver
*/
return platform_driver_register(&xilinxfb_platform_driver);
}
static void __exit
xilinxfb_cleanup(void)
{
platform_driver_unregister(&xilinxfb_platform_driver);
}
module_init(xilinxfb_init);
module_exit(xilinxfb_cleanup);
MODULE_AUTHOR("MontaVista Software, Inc. <source@mvista.com>");
MODULE_DESCRIPTION(DRIVER_DESCRIPTION);
MODULE_LICENSE("GPL");
