From 537a1bf059fa312355696fa6db80726e655e7f17 Mon Sep 17 00:00:00 2001 From: Krzysztof Helt Date: Tue, 30 Jun 2009 11:41:29 -0700 Subject: 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 Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/video/sh7760fb.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) (limited to 'drivers/video/sh7760fb.c') diff --git a/drivers/video/sh7760fb.c b/drivers/video/sh7760fb.c index 653bdfee3057..9f6d6e61f0cc 100644 --- a/drivers/video/sh7760fb.c +++ b/drivers/video/sh7760fb.c @@ -120,18 +120,6 @@ static int sh7760_setcolreg (u_int regno, return 0; } -static void encode_fix(struct fb_fix_screeninfo *fix, struct fb_info *info, - unsigned long stride) -{ - memset(fix, 0, sizeof(struct fb_fix_screeninfo)); - strcpy(fix->id, "sh7760-lcdc"); - - fix->smem_start = (unsigned long)info->screen_base; - fix->smem_len = info->screen_size; - - fix->line_length = stride; -} - static int sh7760fb_get_color_info(struct device *dev, u16 lddfr, int *bpp, int *gray) { @@ -334,7 +322,8 @@ static int sh7760fb_set_par(struct fb_info *info) iowrite32(ldsarl, par->base + LDSARL); /* mem for lower half of DSTN */ - encode_fix(&info->fix, info, stride); + info->fix.line_length = stride; + sh7760fb_check_var(&info->var, info); sh7760fb_blank(FB_BLANK_UNBLANK, info); /* panel on! */ @@ -435,6 +424,8 @@ static int sh7760fb_alloc_mem(struct fb_info *info) 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; } @@ -520,6 +511,8 @@ static int __devinit sh7760fb_probe(struct platform_device *pdev) 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. */ -- cgit v1.2.1