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linux/drivers/video/sh7760fb.c
Krzysztof Helt 537a1bf059 fbdev: add mutex for fb_mmap locking
Add a mutex to avoid a circular locking problem between the mm layer
semaphore and fbdev ioctl mutex through the fb_mmap() call.

Also, add mutex to all places where smem_start and smem_len fields change
so the mutex inside the fb_mmap() is actually used.  Changing of these
fields before calling the framebuffer_register() are not mutexed.

This is 2.6.31 material.  It removes one lockdep (fb_mmap() and
register_framebuffer()) but there is still another one (fb_release() and
register_framebuffer()).  It also cleans up handling of the smem_start and
smem_len fields used by mutexed section of the fb_mmap().

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-30 18:56:00 -07:00

605 lines
14 KiB
C

/*
* SH7760/SH7763 LCDC Framebuffer driver.
*
* (c) 2006-2008 MSC Vertriebsges.m.b.H.,
* Manuel Lauss <mano@roarinelk.homelinux.net>
* (c) 2008 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
*
* 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.
*
* PLEASE HAVE A LOOK AT Documentation/fb/sh7760fb.txt!
*
* Thanks to Siegfried Schaefer <s.schaefer at schaefer-edv.de>
* for his original source and testing!
*
* sh7760_setcolreg get from drivers/video/sh_mobile_lcdcfb.c
*/
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/fb.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <asm/sh7760fb.h>
struct sh7760fb_par {
void __iomem *base;
int irq;
struct sh7760fb_platdata *pd; /* display information */
dma_addr_t fbdma; /* physical address */
int rot; /* rotation enabled? */
u32 pseudo_palette[16];
struct platform_device *dev;
struct resource *ioarea;
struct completion vsync; /* vsync irq event */
};
static irqreturn_t sh7760fb_irq(int irq, void *data)
{
struct completion *c = data;
complete(c);
return IRQ_HANDLED;
}
/* wait_for_lps - wait until power supply has reached a certain state. */
static int wait_for_lps(struct sh7760fb_par *par, int val)
{
int i = 100;
while (--i && ((ioread16(par->base + LDPMMR) & 3) != val))
msleep(1);
if (i <= 0)
return -ETIMEDOUT;
return 0;
}
/* en/disable the LCDC */
static int sh7760fb_blank(int blank, struct fb_info *info)
{
struct sh7760fb_par *par = info->par;
struct sh7760fb_platdata *pd = par->pd;
unsigned short cntr = ioread16(par->base + LDCNTR);
unsigned short intr = ioread16(par->base + LDINTR);
int lps;
if (blank == FB_BLANK_UNBLANK) {
intr |= VINT_START;
cntr = LDCNTR_DON2 | LDCNTR_DON;
lps = 3;
} else {
intr &= ~VINT_START;
cntr = LDCNTR_DON2;
lps = 0;
}
if (pd->blank)
pd->blank(blank);
iowrite16(intr, par->base + LDINTR);
iowrite16(cntr, par->base + LDCNTR);
return wait_for_lps(par, lps);
}
static int sh7760_setcolreg (u_int regno,
u_int red, u_int green, u_int blue,
u_int transp, struct fb_info *info)
{
u32 *palette = info->pseudo_palette;
if (regno >= 16)
return -EINVAL;
/* only FB_VISUAL_TRUECOLOR supported */
red >>= 16 - info->var.red.length;
green >>= 16 - info->var.green.length;
blue >>= 16 - info->var.blue.length;
transp >>= 16 - info->var.transp.length;
palette[regno] = (red << info->var.red.offset) |
(green << info->var.green.offset) |
(blue << info->var.blue.offset) |
(transp << info->var.transp.offset);
return 0;
}
static int sh7760fb_get_color_info(struct device *dev,
u16 lddfr, int *bpp, int *gray)
{
int lbpp, lgray;
lgray = lbpp = 0;
switch (lddfr & LDDFR_COLOR_MASK) {
case LDDFR_1BPP_MONO:
lgray = 1;
lbpp = 1;
break;
case LDDFR_2BPP_MONO:
lgray = 1;
lbpp = 2;
break;
case LDDFR_4BPP_MONO:
lgray = 1;
case LDDFR_4BPP:
lbpp = 4;
break;
case LDDFR_6BPP_MONO:
lgray = 1;
case LDDFR_8BPP:
lbpp = 8;
break;
case LDDFR_16BPP_RGB555:
case LDDFR_16BPP_RGB565:
lbpp = 16;
lgray = 0;
break;
default:
dev_dbg(dev, "unsupported LDDFR bit depth.\n");
return -EINVAL;
}
if (bpp)
*bpp = lbpp;
if (gray)
*gray = lgray;
return 0;
}
static int sh7760fb_check_var(struct fb_var_screeninfo *var,
struct fb_info *info)
{
struct fb_fix_screeninfo *fix = &info->fix;
struct sh7760fb_par *par = info->par;
int ret, bpp;
/* get color info from register value */
ret = sh7760fb_get_color_info(info->dev, par->pd->lddfr, &bpp, NULL);
if (ret)
return ret;
var->bits_per_pixel = bpp;
if ((var->grayscale) && (var->bits_per_pixel == 1))
fix->visual = FB_VISUAL_MONO10;
else if (var->bits_per_pixel >= 15)
fix->visual = FB_VISUAL_TRUECOLOR;
else
fix->visual = FB_VISUAL_PSEUDOCOLOR;
/* TODO: add some more validation here */
return 0;
}
/*
* sh7760fb_set_par - set videomode.
*
* NOTE: The rotation, grayscale and DSTN codepaths are
* totally untested!
*/
static int sh7760fb_set_par(struct fb_info *info)
{
struct sh7760fb_par *par = info->par;
struct fb_videomode *vm = par->pd->def_mode;
unsigned long sbase, dstn_off, ldsarl, stride;
unsigned short hsynp, hsynw, htcn, hdcn;
unsigned short vsynp, vsynw, vtln, vdln;
unsigned short lddfr, ldmtr;
int ret, bpp, gray;
par->rot = par->pd->rotate;
/* rotate only works with xres <= 320 */
if (par->rot && (vm->xres > 320)) {
dev_dbg(info->dev, "rotation disabled due to display size\n");
par->rot = 0;
}
/* calculate LCDC reg vals from display parameters */
hsynp = vm->right_margin + vm->xres;
hsynw = vm->hsync_len;
htcn = vm->left_margin + hsynp + hsynw;
hdcn = vm->xres;
vsynp = vm->lower_margin + vm->yres;
vsynw = vm->vsync_len;
vtln = vm->upper_margin + vsynp + vsynw;
vdln = vm->yres;
/* get color info from register value */
ret = sh7760fb_get_color_info(info->dev, par->pd->lddfr, &bpp, &gray);
if (ret)
return ret;
dev_dbg(info->dev, "%dx%d %dbpp %s (orientation %s)\n", hdcn,
vdln, bpp, gray ? "grayscale" : "color",
par->rot ? "rotated" : "normal");
#ifdef CONFIG_CPU_LITTLE_ENDIAN
lddfr = par->pd->lddfr | (1 << 8);
#else
lddfr = par->pd->lddfr & ~(1 << 8);
#endif
ldmtr = par->pd->ldmtr;
if (!(vm->sync & FB_SYNC_HOR_HIGH_ACT))
ldmtr |= LDMTR_CL1POL;
if (!(vm->sync & FB_SYNC_VERT_HIGH_ACT))
ldmtr |= LDMTR_FLMPOL;
/* shut down LCDC before changing display parameters */
sh7760fb_blank(FB_BLANK_POWERDOWN, info);
iowrite16(par->pd->ldickr, par->base + LDICKR); /* pixclock */
iowrite16(ldmtr, par->base + LDMTR); /* polarities */
iowrite16(lddfr, par->base + LDDFR); /* color/depth */
iowrite16((par->rot ? 1 << 13 : 0), par->base + LDSMR); /* rotate */
iowrite16(par->pd->ldpmmr, par->base + LDPMMR); /* Power Management */
iowrite16(par->pd->ldpspr, par->base + LDPSPR); /* Power Supply Ctrl */
/* display resolution */
iowrite16(((htcn >> 3) - 1) | (((hdcn >> 3) - 1) << 8),
par->base + LDHCNR);
iowrite16(vdln - 1, par->base + LDVDLNR);
iowrite16(vtln - 1, par->base + LDVTLNR);
/* h/v sync signals */
iowrite16((vsynp - 1) | ((vsynw - 1) << 12), par->base + LDVSYNR);
iowrite16(((hsynp >> 3) - 1) | (((hsynw >> 3) - 1) << 12),
par->base + LDHSYNR);
/* AC modulation sig */
iowrite16(par->pd->ldaclnr, par->base + LDACLNR);
stride = (par->rot) ? vtln : hdcn;
if (!gray)
stride *= (bpp + 7) >> 3;
else {
if (bpp == 1)
stride >>= 3;
else if (bpp == 2)
stride >>= 2;
else if (bpp == 4)
stride >>= 1;
/* 6 bpp == 8 bpp */
}
/* if rotated, stride must be power of 2 */
if (par->rot) {
unsigned long bit = 1 << 31;
while (bit) {
if (stride & bit)
break;
bit >>= 1;
}
if (stride & ~bit)
stride = bit << 1; /* not P-o-2, round up */
}
iowrite16(stride, par->base + LDLAOR);
/* set display mem start address */
sbase = (unsigned long)par->fbdma;
if (par->rot)
sbase += (hdcn - 1) * stride;
iowrite32(sbase, par->base + LDSARU);
/*
* for DSTN need to set address for lower half.
* I (mlau) don't know which address to set it to,
* so I guessed at (stride * yres/2).
*/
if (((ldmtr & 0x003f) >= LDMTR_DSTN_MONO_8) &&
((ldmtr & 0x003f) <= LDMTR_DSTN_COLOR_16)) {
dev_dbg(info->dev, " ***** DSTN untested! *****\n");
dstn_off = stride;
if (par->rot)
dstn_off *= hdcn >> 1;
else
dstn_off *= vdln >> 1;
ldsarl = sbase + dstn_off;
} else
ldsarl = 0;
iowrite32(ldsarl, par->base + LDSARL); /* mem for lower half of DSTN */
info->fix.line_length = stride;
sh7760fb_check_var(&info->var, info);
sh7760fb_blank(FB_BLANK_UNBLANK, info); /* panel on! */
dev_dbg(info->dev, "hdcn : %6d htcn : %6d\n", hdcn, htcn);
dev_dbg(info->dev, "hsynw : %6d hsynp : %6d\n", hsynw, hsynp);
dev_dbg(info->dev, "vdln : %6d vtln : %6d\n", vdln, vtln);
dev_dbg(info->dev, "vsynw : %6d vsynp : %6d\n", vsynw, vsynp);
dev_dbg(info->dev, "clksrc: %6d clkdiv: %6d\n",
(par->pd->ldickr >> 12) & 3, par->pd->ldickr & 0x1f);
dev_dbg(info->dev, "ldpmmr: 0x%04x ldpspr: 0x%04x\n", par->pd->ldpmmr,
par->pd->ldpspr);
dev_dbg(info->dev, "ldmtr : 0x%04x lddfr : 0x%04x\n", ldmtr, lddfr);
dev_dbg(info->dev, "ldlaor: %ld\n", stride);
dev_dbg(info->dev, "ldsaru: 0x%08lx ldsarl: 0x%08lx\n", sbase, ldsarl);
return 0;
}
static struct fb_ops sh7760fb_ops = {
.owner = THIS_MODULE,
.fb_blank = sh7760fb_blank,
.fb_check_var = sh7760fb_check_var,
.fb_setcolreg = sh7760_setcolreg,
.fb_set_par = sh7760fb_set_par,
.fb_fillrect = cfb_fillrect,
.fb_copyarea = cfb_copyarea,
.fb_imageblit = cfb_imageblit,
};
static void sh7760fb_free_mem(struct fb_info *info)
{
struct sh7760fb_par *par = info->par;
if (!info->screen_base)
return;
dma_free_coherent(info->dev, info->screen_size,
info->screen_base, par->fbdma);
par->fbdma = 0;
info->screen_base = NULL;
info->screen_size = 0;
}
/* allocate the framebuffer memory. This memory must be in Area3,
* (dictated by the DMA engine) and contiguous, at a 512 byte boundary.
*/
static int sh7760fb_alloc_mem(struct fb_info *info)
{
struct sh7760fb_par *par = info->par;
void *fbmem;
unsigned long vram;
int ret, bpp;
if (info->screen_base)
return 0;
/* get color info from register value */
ret = sh7760fb_get_color_info(info->dev, par->pd->lddfr, &bpp, NULL);
if (ret) {
printk(KERN_ERR "colinfo\n");
return ret;
}
/* min VRAM: xres_min = 16, yres_min = 1, bpp = 1: 2byte -> 1 page
max VRAM: xres_max = 1024, yres_max = 1024, bpp = 16: 2MB */
vram = info->var.xres * info->var.yres;
if (info->var.grayscale) {
if (bpp == 1)
vram >>= 3;
else if (bpp == 2)
vram >>= 2;
else if (bpp == 4)
vram >>= 1;
} else if (bpp > 8)
vram *= 2;
if ((vram < 1) || (vram > 1024 * 2048)) {
dev_dbg(info->dev, "too much VRAM required. Check settings\n");
return -ENODEV;
}
if (vram < PAGE_SIZE)
vram = PAGE_SIZE;
fbmem = dma_alloc_coherent(info->dev, vram, &par->fbdma, GFP_KERNEL);
if (!fbmem)
return -ENOMEM;
if ((par->fbdma & SH7760FB_DMA_MASK) != SH7760FB_DMA_MASK) {
sh7760fb_free_mem(info);
dev_err(info->dev, "kernel gave me memory at 0x%08lx, which is"
"unusable for the LCDC\n", (unsigned long)par->fbdma);
return -ENOMEM;
}
info->screen_base = fbmem;
info->screen_size = vram;
info->fix.smem_start = (unsigned long)info->screen_base;
info->fix.smem_len = info->screen_size;
return 0;
}
static int __devinit sh7760fb_probe(struct platform_device *pdev)
{
struct fb_info *info;
struct resource *res;
struct sh7760fb_par *par;
int ret;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (unlikely(res == NULL)) {
dev_err(&pdev->dev, "invalid resource\n");
return -EINVAL;
}
info = framebuffer_alloc(sizeof(struct sh7760fb_par), &pdev->dev);
if (!info)
return -ENOMEM;
par = info->par;
par->dev = pdev;
par->pd = pdev->dev.platform_data;
if (!par->pd) {
dev_dbg(info->dev, "no display setup data!\n");
ret = -ENODEV;
goto out_fb;
}
par->ioarea = request_mem_region(res->start,
(res->end - res->start), pdev->name);
if (!par->ioarea) {
dev_err(&pdev->dev, "mmio area busy\n");
ret = -EBUSY;
goto out_fb;
}
par->base = ioremap_nocache(res->start, res->end - res->start + 1);
if (!par->base) {
dev_err(&pdev->dev, "cannot remap\n");
ret = -ENODEV;
goto out_res;
}
iowrite16(0, par->base + LDINTR); /* disable vsync irq */
par->irq = platform_get_irq(pdev, 0);
if (par->irq >= 0) {
ret = request_irq(par->irq, sh7760fb_irq, 0,
"sh7760-lcdc", &par->vsync);
if (ret) {
dev_err(&pdev->dev, "cannot grab IRQ\n");
par->irq = -ENXIO;
} else
disable_irq_nosync(par->irq);
}
fb_videomode_to_var(&info->var, par->pd->def_mode);
ret = sh7760fb_alloc_mem(info);
if (ret) {
dev_dbg(info->dev, "framebuffer memory allocation failed!\n");
goto out_unmap;
}
info->pseudo_palette = par->pseudo_palette;
/* fixup color register bitpositions. These are fixed by hardware */
info->var.red.offset = 11;
info->var.red.length = 5;
info->var.red.msb_right = 0;
info->var.green.offset = 5;
info->var.green.length = 6;
info->var.green.msb_right = 0;
info->var.blue.offset = 0;
info->var.blue.length = 5;
info->var.blue.msb_right = 0;
info->var.transp.offset = 0;
info->var.transp.length = 0;
info->var.transp.msb_right = 0;
strcpy(info->fix.id, "sh7760-lcdc");
/* set the DON2 bit now, before cmap allocation, as it will randomize
* palette memory.
*/
iowrite16(LDCNTR_DON2, par->base + LDCNTR);
info->fbops = &sh7760fb_ops;
ret = fb_alloc_cmap(&info->cmap, 256, 0);
if (ret) {
dev_dbg(info->dev, "Unable to allocate cmap memory\n");
goto out_mem;
}
ret = register_framebuffer(info);
if (ret < 0) {
dev_dbg(info->dev, "cannot register fb!\n");
goto out_cmap;
}
platform_set_drvdata(pdev, info);
printk(KERN_INFO "%s: memory at phys 0x%08lx-0x%08lx, size %ld KiB\n",
pdev->name,
(unsigned long)par->fbdma,
(unsigned long)(par->fbdma + info->screen_size - 1),
info->screen_size >> 10);
return 0;
out_cmap:
sh7760fb_blank(FB_BLANK_POWERDOWN, info);
fb_dealloc_cmap(&info->cmap);
out_mem:
sh7760fb_free_mem(info);
out_unmap:
if (par->irq >= 0)
free_irq(par->irq, &par->vsync);
iounmap(par->base);
out_res:
release_resource(par->ioarea);
kfree(par->ioarea);
out_fb:
framebuffer_release(info);
return ret;
}
static int __devexit sh7760fb_remove(struct platform_device *dev)
{
struct fb_info *info = platform_get_drvdata(dev);
struct sh7760fb_par *par = info->par;
sh7760fb_blank(FB_BLANK_POWERDOWN, info);
unregister_framebuffer(info);
fb_dealloc_cmap(&info->cmap);
sh7760fb_free_mem(info);
if (par->irq >= 0)
free_irq(par->irq, par);
iounmap(par->base);
release_resource(par->ioarea);
kfree(par->ioarea);
framebuffer_release(info);
platform_set_drvdata(dev, NULL);
return 0;
}
static struct platform_driver sh7760_lcdc_driver = {
.driver = {
.name = "sh7760-lcdc",
.owner = THIS_MODULE,
},
.probe = sh7760fb_probe,
.remove = __devexit_p(sh7760fb_remove),
};
static int __init sh7760fb_init(void)
{
return platform_driver_register(&sh7760_lcdc_driver);
}
static void __exit sh7760fb_exit(void)
{
platform_driver_unregister(&sh7760_lcdc_driver);
}
module_init(sh7760fb_init);
module_exit(sh7760fb_exit);
MODULE_AUTHOR("Nobuhiro Iwamatsu, Manuel Lauss");
MODULE_DESCRIPTION("FBdev for SH7760/63 integrated LCD Controller");
MODULE_LICENSE("GPL");