Merge tag 'v5.0.19' into toradex_5.0.ytoradex_5.0.y

This is the 5.0.19 stable release

4 files changed, 296 insertions, 81 deletions

diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
index ba906876cc45..fd02e8a4841d 100644
--- a/drivers/video/fbdev/efifb.c
+++ b/drivers/video/fbdev/efifb.c
@@ -476,8 +476,12 @@ static int efifb_probe(struct platform_device *dev)
 		 * If the UEFI memory map covers the efifb region, we may only
 		 * remap it using the attributes the memory map prescribes.
 		 */
-		mem_flags |= EFI_MEMORY_WT | EFI_MEMORY_WB;
-		mem_flags &= md.attribute;
+		md.attribute &= EFI_MEMORY_UC | EFI_MEMORY_WC |
+				EFI_MEMORY_WT | EFI_MEMORY_WB;
+		if (md.attribute) {
+			mem_flags |= EFI_MEMORY_WT | EFI_MEMORY_WB;
+			mem_flags &= md.attribute;
+		}
 	}
 	if (mem_flags & EFI_MEMORY_WC)
 		info->screen_base = ioremap_wc(efifb_fix.smem_start,
diff --git a/drivers/video/fbdev/sm712.h b/drivers/video/fbdev/sm712.h
index aad1cc4be34a..c7ebf03b8d53 100644
--- a/drivers/video/fbdev/sm712.h
+++ b/drivers/video/fbdev/sm712.h
@@ -15,14 +15,10 @@
 
 #define FB_ACCEL_SMI_LYNX 88
 
-#define SCREEN_X_RES      1024
-#define SCREEN_Y_RES      600
-#define SCREEN_BPP        16
-
-/*Assume SM712 graphics chip has 4MB VRAM */
-#define SM712_VIDEOMEMORYSIZE	  0x00400000
-/*Assume SM722 graphics chip has 8MB VRAM */
-#define SM722_VIDEOMEMORYSIZE	  0x00800000
+#define SCREEN_X_RES          1024
+#define SCREEN_Y_RES_PC       768
+#define SCREEN_Y_RES_NETBOOK  600
+#define SCREEN_BPP            16
 
 #define dac_reg	(0x3c8)
 #define dac_val	(0x3c9)
diff --git a/drivers/video/fbdev/sm712fb.c b/drivers/video/fbdev/sm712fb.c
index 502d0de2feec..f1dcc6766d1e 100644
--- a/drivers/video/fbdev/sm712fb.c
+++ b/drivers/video/fbdev/sm712fb.c
@@ -530,6 +530,65 @@ static const struct modeinit vgamode[] = {
 			0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x15, 0x03,
 		},
 	},
+	{	/*  1024 x 768  16Bpp  60Hz */
+		1024, 768, 16, 60,
+		/*  Init_MISC */
+		0xEB,
+		{	/*  Init_SR0_SR4 */
+			0x03, 0x01, 0x0F, 0x03, 0x0E,
+		},
+		{	/*  Init_SR10_SR24 */
+			0xF3, 0xB6, 0xC0, 0xDD, 0x00, 0x0E, 0x17, 0x2C,
+			0x99, 0x02, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0xC4, 0x30, 0x02, 0x01, 0x01,
+		},
+		{	/*  Init_SR30_SR75 */
+			0x38, 0x03, 0x20, 0x09, 0xC0, 0x3A, 0x3A, 0x3A,
+			0x3A, 0x3A, 0x3A, 0x3A, 0x00, 0x00, 0x03, 0xFF,
+			0x00, 0xFC, 0x00, 0x00, 0x20, 0x18, 0x00, 0xFC,
+			0x20, 0x0C, 0x44, 0x20, 0x00, 0x00, 0x00, 0x3A,
+			0x06, 0x68, 0xA7, 0x7F, 0x83, 0x24, 0xFF, 0x03,
+			0x0F, 0x60, 0x59, 0x3A, 0x3A, 0x00, 0x00, 0x3A,
+			0x01, 0x80, 0x7E, 0x1A, 0x1A, 0x00, 0x00, 0x00,
+			0x50, 0x03, 0x74, 0x14, 0x3B, 0x0D, 0x09, 0x02,
+			0x04, 0x45, 0x30, 0x30, 0x40, 0x20,
+		},
+		{	/*  Init_SR80_SR93 */
+			0xFF, 0x07, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0x3A,
+			0xF7, 0x00, 0x00, 0x00, 0xFF, 0xFF, 0x3A, 0x3A,
+			0x00, 0x00, 0x00, 0x00,
+		},
+		{	/*  Init_SRA0_SRAF */
+			0x00, 0xFB, 0x9F, 0x01, 0x00, 0xED, 0xED, 0xED,
+			0x7B, 0xFB, 0xFF, 0xFF, 0x97, 0xEF, 0xBF, 0xDF,
+		},
+		{	/*  Init_GR00_GR08 */
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x40, 0x05, 0x0F,
+			0xFF,
+		},
+		{	/*  Init_AR00_AR14 */
+			0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+			0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,
+			0x41, 0x00, 0x0F, 0x00, 0x00,
+		},
+		{	/*  Init_CR00_CR18 */
+			0xA3, 0x7F, 0x7F, 0x00, 0x85, 0x16, 0x24, 0xF5,
+			0x00, 0x60, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+			0x03, 0x09, 0xFF, 0x80, 0x40, 0xFF, 0x00, 0xE3,
+			0xFF,
+		},
+		{	/*  Init_CR30_CR4D */
+			0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0x02, 0x20,
+			0x00, 0x00, 0x00, 0x40, 0x00, 0xFF, 0xBF, 0xFF,
+			0xA3, 0x7F, 0x00, 0x86, 0x15, 0x24, 0xFF, 0x00,
+			0x01, 0x07, 0xE5, 0x20, 0x7F, 0xFF,
+		},
+		{	/*  Init_CR90_CRA7 */
+			0x55, 0xD9, 0x5D, 0xE1, 0x86, 0x1B, 0x8E, 0x26,
+			0xDA, 0x8D, 0xDE, 0x94, 0x00, 0x00, 0x18, 0x00,
+			0x03, 0x03, 0x03, 0x03, 0x03, 0x03, 0x15, 0x03,
+		},
+	},
 	{	/*  mode#5: 1024 x 768  24Bpp  60Hz */
 		1024, 768, 24, 60,
 		/*  Init_MISC */
@@ -827,67 +886,80 @@ static inline unsigned int chan_to_field(unsigned int chan,
 
 static int smtc_blank(int blank_mode, struct fb_info *info)
 {
+	struct smtcfb_info *sfb = info->par;
+
 	/* clear DPMS setting */
 	switch (blank_mode) {
 	case FB_BLANK_UNBLANK:
 		/* Screen On: HSync: On, VSync : On */
+
+		switch (sfb->chip_id) {
+		case 0x710:
+		case 0x712:
+			smtc_seqw(0x6a, 0x16);
+			smtc_seqw(0x6b, 0x02);
+			break;
+		case 0x720:
+			smtc_seqw(0x6a, 0x0d);
+			smtc_seqw(0x6b, 0x02);
+			break;
+		}
+
+		smtc_seqw(0x23, (smtc_seqr(0x23) & (~0xc0)));
 		smtc_seqw(0x01, (smtc_seqr(0x01) & (~0x20)));
-		smtc_seqw(0x6a, 0x16);
-		smtc_seqw(0x6b, 0x02);
 		smtc_seqw(0x21, (smtc_seqr(0x21) & 0x77));
 		smtc_seqw(0x22, (smtc_seqr(0x22) & (~0x30)));
-		smtc_seqw(0x23, (smtc_seqr(0x23) & (~0xc0)));
-		smtc_seqw(0x24, (smtc_seqr(0x24) | 0x01));
 		smtc_seqw(0x31, (smtc_seqr(0x31) | 0x03));
+		smtc_seqw(0x24, (smtc_seqr(0x24) | 0x01));
 		break;
 	case FB_BLANK_NORMAL:
 		/* Screen Off: HSync: On, VSync : On   Soft blank */
+		smtc_seqw(0x24, (smtc_seqr(0x24) | 0x01));
+		smtc_seqw(0x31, ((smtc_seqr(0x31) & (~0x07)) | 0x00));
+		smtc_seqw(0x23, (smtc_seqr(0x23) & (~0xc0)));
 		smtc_seqw(0x01, (smtc_seqr(0x01) & (~0x20)));
+		smtc_seqw(0x22, (smtc_seqr(0x22) & (~0x30)));
 		smtc_seqw(0x6a, 0x16);
 		smtc_seqw(0x6b, 0x02);
-		smtc_seqw(0x22, (smtc_seqr(0x22) & (~0x30)));
-		smtc_seqw(0x23, (smtc_seqr(0x23) & (~0xc0)));
-		smtc_seqw(0x24, (smtc_seqr(0x24) | 0x01));
-		smtc_seqw(0x31, ((smtc_seqr(0x31) & (~0x07)) | 0x00));
 		break;
 	case FB_BLANK_VSYNC_SUSPEND:
 		/* Screen On: HSync: On, VSync : Off */
+		smtc_seqw(0x24, (smtc_seqr(0x24) & (~0x01)));
+		smtc_seqw(0x31, ((smtc_seqr(0x31) & (~0x07)) | 0x00));
+		smtc_seqw(0x23, ((smtc_seqr(0x23) & (~0xc0)) | 0x20));
 		smtc_seqw(0x01, (smtc_seqr(0x01) | 0x20));
-		smtc_seqw(0x20, (smtc_seqr(0x20) & (~0xB0)));
-		smtc_seqw(0x6a, 0x0c);
-		smtc_seqw(0x6b, 0x02);
 		smtc_seqw(0x21, (smtc_seqr(0x21) | 0x88));
+		smtc_seqw(0x20, (smtc_seqr(0x20) & (~0xB0)));
 		smtc_seqw(0x22, ((smtc_seqr(0x22) & (~0x30)) | 0x20));
-		smtc_seqw(0x23, ((smtc_seqr(0x23) & (~0xc0)) | 0x20));
-		smtc_seqw(0x24, (smtc_seqr(0x24) & (~0x01)));
-		smtc_seqw(0x31, ((smtc_seqr(0x31) & (~0x07)) | 0x00));
 		smtc_seqw(0x34, (smtc_seqr(0x34) | 0x80));
+		smtc_seqw(0x6a, 0x0c);
+		smtc_seqw(0x6b, 0x02);
 		break;
 	case FB_BLANK_HSYNC_SUSPEND:
 		/* Screen On: HSync: Off, VSync : On */
+		smtc_seqw(0x24, (smtc_seqr(0x24) & (~0x01)));
+		smtc_seqw(0x31, ((smtc_seqr(0x31) & (~0x07)) | 0x00));
+		smtc_seqw(0x23, ((smtc_seqr(0x23) & (~0xc0)) | 0xD8));
 		smtc_seqw(0x01, (smtc_seqr(0x01) | 0x20));
-		smtc_seqw(0x20, (smtc_seqr(0x20) & (~0xB0)));
-		smtc_seqw(0x6a, 0x0c);
-		smtc_seqw(0x6b, 0x02);
 		smtc_seqw(0x21, (smtc_seqr(0x21) | 0x88));
+		smtc_seqw(0x20, (smtc_seqr(0x20) & (~0xB0)));
 		smtc_seqw(0x22, ((smtc_seqr(0x22) & (~0x30)) | 0x10));
-		smtc_seqw(0x23, ((smtc_seqr(0x23) & (~0xc0)) | 0xD8));
-		smtc_seqw(0x24, (smtc_seqr(0x24) & (~0x01)));
-		smtc_seqw(0x31, ((smtc_seqr(0x31) & (~0x07)) | 0x00));
 		smtc_seqw(0x34, (smtc_seqr(0x34) | 0x80));
+		smtc_seqw(0x6a, 0x0c);
+		smtc_seqw(0x6b, 0x02);
 		break;
 	case FB_BLANK_POWERDOWN:
 		/* Screen On: HSync: Off, VSync : Off */
+		smtc_seqw(0x24, (smtc_seqr(0x24) & (~0x01)));
+		smtc_seqw(0x31, ((smtc_seqr(0x31) & (~0x07)) | 0x00));
+		smtc_seqw(0x23, ((smtc_seqr(0x23) & (~0xc0)) | 0xD8));
 		smtc_seqw(0x01, (smtc_seqr(0x01) | 0x20));
-		smtc_seqw(0x20, (smtc_seqr(0x20) & (~0xB0)));
-		smtc_seqw(0x6a, 0x0c);
-		smtc_seqw(0x6b, 0x02);
 		smtc_seqw(0x21, (smtc_seqr(0x21) | 0x88));
+		smtc_seqw(0x20, (smtc_seqr(0x20) & (~0xB0)));
 		smtc_seqw(0x22, ((smtc_seqr(0x22) & (~0x30)) | 0x30));
-		smtc_seqw(0x23, ((smtc_seqr(0x23) & (~0xc0)) | 0xD8));
-		smtc_seqw(0x24, (smtc_seqr(0x24) & (~0x01)));
-		smtc_seqw(0x31, ((smtc_seqr(0x31) & (~0x07)) | 0x00));
 		smtc_seqw(0x34, (smtc_seqr(0x34) | 0x80));
+		smtc_seqw(0x6a, 0x0c);
+		smtc_seqw(0x6b, 0x02);
 		break;
 	default:
 		return -EINVAL;
@@ -1145,8 +1217,10 @@ static void sm7xx_set_timing(struct smtcfb_info *sfb)
 
 		/* init SEQ register SR30 - SR75 */
 		for (i = 0; i < SIZE_SR30_SR75; i++)
-			if ((i + 0x30) != 0x62 && (i + 0x30) != 0x6a &&
-			    (i + 0x30) != 0x6b)
+			if ((i + 0x30) != 0x30 && (i + 0x30) != 0x62 &&
+			    (i + 0x30) != 0x6a && (i + 0x30) != 0x6b &&
+			    (i + 0x30) != 0x70 && (i + 0x30) != 0x71 &&
+			    (i + 0x30) != 0x74 && (i + 0x30) != 0x75)
 				smtc_seqw(i + 0x30,
 					  vgamode[j].init_sr30_sr75[i]);
 
@@ -1171,8 +1245,12 @@ static void sm7xx_set_timing(struct smtcfb_info *sfb)
 			smtc_crtcw(i, vgamode[j].init_cr00_cr18[i]);
 
 		/* init CRTC register CR30 - CR4D */
-		for (i = 0; i < SIZE_CR30_CR4D; i++)
+		for (i = 0; i < SIZE_CR30_CR4D; i++) {
+			if ((i + 0x30) >= 0x3B && (i + 0x30) <= 0x3F)
+				/* side-effect, don't write to CR3B-CR3F */
+				continue;
 			smtc_crtcw(i + 0x30, vgamode[j].init_cr30_cr4d[i]);
+		}
 
 		/* init CRTC register CR90 - CRA7 */
 		for (i = 0; i < SIZE_CR90_CRA7; i++)
@@ -1323,6 +1401,11 @@ static int smtc_map_smem(struct smtcfb_info *sfb,
 {
 	sfb->fb->fix.smem_start = pci_resource_start(pdev, 0);
 
+	if (sfb->chip_id == 0x720)
+		/* on SM720, the framebuffer starts at the 1 MB offset */
+		sfb->fb->fix.smem_start += 0x00200000;
+
+	/* XXX: is it safe for SM720 on Big-Endian? */
 	if (sfb->fb->var.bits_per_pixel == 32)
 		sfb->fb->fix.smem_start += big_addr;
 
@@ -1360,12 +1443,82 @@ static inline void sm7xx_init_hw(void)
 	outb_p(0x11, 0x3c5);
 }
 
+static u_long sm7xx_vram_probe(struct smtcfb_info *sfb)
+{
+	u8 vram;
+
+	switch (sfb->chip_id) {
+	case 0x710:
+	case 0x712:
+		/*
+		 * Assume SM712 graphics chip has 4MB VRAM.
+		 *
+		 * FIXME: SM712 can have 2MB VRAM, which is used on earlier
+		 * laptops, such as IBM Thinkpad 240X. This driver would
+		 * probably crash on those machines. If anyone gets one of
+		 * those and is willing to help, run "git blame" and send me
+		 * an E-mail.
+		 */
+		return 0x00400000;
+	case 0x720:
+		outb_p(0x76, 0x3c4);
+		vram = inb_p(0x3c5) >> 6;
+
+		if (vram == 0x00)
+			return 0x00800000;  /* 8 MB */
+		else if (vram == 0x01)
+			return 0x01000000;  /* 16 MB */
+		else if (vram == 0x02)
+			return 0x00400000;  /* illegal, fallback to 4 MB */
+		else if (vram == 0x03)
+			return 0x00400000;  /* 4 MB */
+	}
+	return 0;  /* unknown hardware */
+}
+
+static void sm7xx_resolution_probe(struct smtcfb_info *sfb)
+{
+	/* get mode parameter from smtc_scr_info */
+	if (smtc_scr_info.lfb_width != 0) {
+		sfb->fb->var.xres = smtc_scr_info.lfb_width;
+		sfb->fb->var.yres = smtc_scr_info.lfb_height;
+		sfb->fb->var.bits_per_pixel = smtc_scr_info.lfb_depth;
+		goto final;
+	}
+
+	/*
+	 * No parameter, default resolution is 1024x768-16.
+	 *
+	 * FIXME: earlier laptops, such as IBM Thinkpad 240X, has a 800x600
+	 * panel, also see the comments about Thinkpad 240X above.
+	 */
+	sfb->fb->var.xres = SCREEN_X_RES;
+	sfb->fb->var.yres = SCREEN_Y_RES_PC;
+	sfb->fb->var.bits_per_pixel = SCREEN_BPP;
+
+#ifdef CONFIG_MIPS
+	/*
+	 * Loongson MIPS netbooks use 1024x600 LCD panels, which is the original
+	 * target platform of this driver, but nearly all old x86 laptops have
+	 * 1024x768. Lighting 768 panels using 600's timings would partially
+	 * garble the display, so we don't want that. But it's not possible to
+	 * distinguish them reliably.
+	 *
+	 * So we change the default to 768, but keep 600 as-is on MIPS.
+	 */
+	sfb->fb->var.yres = SCREEN_Y_RES_NETBOOK;
+#endif
+
+final:
+	big_pixel_depth(sfb->fb->var.bits_per_pixel, smtc_scr_info.lfb_depth);
+}
+
 static int smtcfb_pci_probe(struct pci_dev *pdev,
 			    const struct pci_device_id *ent)
 {
 	struct smtcfb_info *sfb;
 	struct fb_info *info;
-	u_long smem_size = 0x00800000;	/* default 8MB */
+	u_long smem_size;
 	int err;
 	unsigned long mmio_base;
 
@@ -1405,29 +1558,19 @@ static int smtcfb_pci_probe(struct pci_dev *pdev,
 
 	sm7xx_init_hw();
 
-	/* get mode parameter from smtc_scr_info */
-	if (smtc_scr_info.lfb_width != 0) {
-		sfb->fb->var.xres = smtc_scr_info.lfb_width;
-		sfb->fb->var.yres = smtc_scr_info.lfb_height;
-		sfb->fb->var.bits_per_pixel = smtc_scr_info.lfb_depth;
-	} else {
-		/* default resolution 1024x600 16bit mode */
-		sfb->fb->var.xres = SCREEN_X_RES;
-		sfb->fb->var.yres = SCREEN_Y_RES;
-		sfb->fb->var.bits_per_pixel = SCREEN_BPP;
-	}
-
-	big_pixel_depth(sfb->fb->var.bits_per_pixel, smtc_scr_info.lfb_depth);
 	/* Map address and memory detection */
 	mmio_base = pci_resource_start(pdev, 0);
 	pci_read_config_byte(pdev, PCI_REVISION_ID, &sfb->chip_rev_id);
 
+	smem_size = sm7xx_vram_probe(sfb);
+	dev_info(&pdev->dev, "%lu MiB of VRAM detected.\n",
+					smem_size / 1048576);
+
 	switch (sfb->chip_id) {
 	case 0x710:
 	case 0x712:
 		sfb->fb->fix.mmio_start = mmio_base + 0x00400000;
 		sfb->fb->fix.mmio_len = 0x00400000;
-		smem_size = SM712_VIDEOMEMORYSIZE;
 		sfb->lfb = ioremap(mmio_base, mmio_addr);
 		if (!sfb->lfb) {
 			dev_err(&pdev->dev,
@@ -1459,8 +1602,7 @@ static int smtcfb_pci_probe(struct pci_dev *pdev,
 	case 0x720:
 		sfb->fb->fix.mmio_start = mmio_base;
 		sfb->fb->fix.mmio_len = 0x00200000;
-		smem_size = SM722_VIDEOMEMORYSIZE;
-		sfb->dp_regs = ioremap(mmio_base, 0x00a00000);
+		sfb->dp_regs = ioremap(mmio_base, 0x00200000 + smem_size);
 		sfb->lfb = sfb->dp_regs + 0x00200000;
 		sfb->mmio = (smtc_regbaseaddress =
 		    sfb->dp_regs + 0x000c0000);
@@ -1477,6 +1619,9 @@ static int smtcfb_pci_probe(struct pci_dev *pdev,
 		goto failed_fb;
 	}
 
+	/* probe and decide resolution */
+	sm7xx_resolution_probe(sfb);
+
 	/* can support 32 bpp */
 	if (sfb->fb->var.bits_per_pixel == 15)
 		sfb->fb->var.bits_per_pixel = 16;
@@ -1487,7 +1632,11 @@ static int smtcfb_pci_probe(struct pci_dev *pdev,
 	if (err)
 		goto failed;
 
-	smtcfb_setmode(sfb);
+	/*
+	 * The screen would be temporarily garbled when sm712fb takes over
+	 * vesafb or VGA text mode. Zero the framebuffer.
+	 */
+	memset_io(sfb->lfb, 0, sfb->fb->fix.smem_len);
 
 	err = register_framebuffer(info);
 	if (err < 0)
diff --git a/drivers/video/fbdev/udlfb.c b/drivers/video/fbdev/udlfb.c
index 1d034dddc556..5a0d6fb02bbc 100644
--- a/drivers/video/fbdev/udlfb.c
+++ b/drivers/video/fbdev/udlfb.c
@@ -594,8 +594,7 @@ static int dlfb_render_hline(struct dlfb_data *dlfb, struct urb **urb_ptr,
 	return 0;
 }
 
-static int dlfb_handle_damage(struct dlfb_data *dlfb, int x, int y,
-	       int width, int height, char *data)
+static int dlfb_handle_damage(struct dlfb_data *dlfb, int x, int y, int width, int height)
 {
 	int i, ret;
 	char *cmd;
@@ -607,21 +606,29 @@ static int dlfb_handle_damage(struct dlfb_data *dlfb, int x, int y,
 
 	start_cycles = get_cycles();
 
+	mutex_lock(&dlfb->render_mutex);
+
 	aligned_x = DL_ALIGN_DOWN(x, sizeof(unsigned long));
 	width = DL_ALIGN_UP(width + (x-aligned_x), sizeof(unsigned long));
 	x = aligned_x;
 
 	if ((width <= 0) ||
 	    (x + width > dlfb->info->var.xres) ||
-	    (y + height > dlfb->info->var.yres))
-		return -EINVAL;
+	    (y + height > dlfb->info->var.yres)) {
+		ret = -EINVAL;
+		goto unlock_ret;
+	}
 
-	if (!atomic_read(&dlfb->usb_active))
-		return 0;
+	if (!atomic_read(&dlfb->usb_active)) {
+		ret = 0;
+		goto unlock_ret;
+	}
 
 	urb = dlfb_get_urb(dlfb);
-	if (!urb)
-		return 0;
+	if (!urb) {
+		ret = 0;
+		goto unlock_ret;
+	}
 	cmd = urb->transfer_buffer;
 
 	for (i = y; i < y + height ; i++) {
@@ -641,7 +648,7 @@ static int dlfb_handle_damage(struct dlfb_data *dlfb, int x, int y,
 			*cmd++ = 0xAF;
 		/* Send partial buffer remaining before exiting */
 		len = cmd - (char *) urb->transfer_buffer;
-		ret = dlfb_submit_urb(dlfb, urb, len);
+		dlfb_submit_urb(dlfb, urb, len);
 		bytes_sent += len;
 	} else
 		dlfb_urb_completion(urb);
@@ -655,7 +662,55 @@ error:
 		    >> 10)), /* Kcycles */
 		   &dlfb->cpu_kcycles_used);
 
-	return 0;
+	ret = 0;
+
+unlock_ret:
+	mutex_unlock(&dlfb->render_mutex);
+	return ret;
+}
+
+static void dlfb_init_damage(struct dlfb_data *dlfb)
+{
+	dlfb->damage_x = INT_MAX;
+	dlfb->damage_x2 = 0;
+	dlfb->damage_y = INT_MAX;
+	dlfb->damage_y2 = 0;
+}
+
+static void dlfb_damage_work(struct work_struct *w)
+{
+	struct dlfb_data *dlfb = container_of(w, struct dlfb_data, damage_work);
+	int x, x2, y, y2;
+
+	spin_lock_irq(&dlfb->damage_lock);
+	x = dlfb->damage_x;
+	x2 = dlfb->damage_x2;
+	y = dlfb->damage_y;
+	y2 = dlfb->damage_y2;
+	dlfb_init_damage(dlfb);
+	spin_unlock_irq(&dlfb->damage_lock);
+
+	if (x < x2 && y < y2)
+		dlfb_handle_damage(dlfb, x, y, x2 - x, y2 - y);
+}
+
+static void dlfb_offload_damage(struct dlfb_data *dlfb, int x, int y, int width, int height)
+{
+	unsigned long flags;
+	int x2 = x + width;
+	int y2 = y + height;
+
+	if (x >= x2 || y >= y2)
+		return;
+
+	spin_lock_irqsave(&dlfb->damage_lock, flags);
+	dlfb->damage_x = min(x, dlfb->damage_x);
+	dlfb->damage_x2 = max(x2, dlfb->damage_x2);
+	dlfb->damage_y = min(y, dlfb->damage_y);
+	dlfb->damage_y2 = max(y2, dlfb->damage_y2);
+	spin_unlock_irqrestore(&dlfb->damage_lock, flags);
+
+	schedule_work(&dlfb->damage_work);
 }
 
 /*
@@ -679,7 +734,7 @@ static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
 				(u32)info->var.yres);
 
 		dlfb_handle_damage(dlfb, 0, start, info->var.xres,
-			lines, info->screen_base);
+			lines);
 	}
 
 	return result;
@@ -694,8 +749,8 @@ static void dlfb_ops_copyarea(struct fb_info *info,
 
 	sys_copyarea(info, area);
 
-	dlfb_handle_damage(dlfb, area->dx, area->dy,
-			area->width, area->height, info->screen_base);
+	dlfb_offload_damage(dlfb, area->dx, area->dy,
+			area->width, area->height);
 }
 
 static void dlfb_ops_imageblit(struct fb_info *info,
@@ -705,8 +760,8 @@ static void dlfb_ops_imageblit(struct fb_info *info,
 
 	sys_imageblit(info, image);
 
-	dlfb_handle_damage(dlfb, image->dx, image->dy,
-			image->width, image->height, info->screen_base);
+	dlfb_offload_damage(dlfb, image->dx, image->dy,
+			image->width, image->height);
 }
 
 static void dlfb_ops_fillrect(struct fb_info *info,
@@ -716,8 +771,8 @@ static void dlfb_ops_fillrect(struct fb_info *info,
 
 	sys_fillrect(info, rect);
 
-	dlfb_handle_damage(dlfb, rect->dx, rect->dy, rect->width,
-			      rect->height, info->screen_base);
+	dlfb_offload_damage(dlfb, rect->dx, rect->dy, rect->width,
+			      rect->height);
 }
 
 /*
@@ -739,17 +794,19 @@ static void dlfb_dpy_deferred_io(struct fb_info *info,
 	int bytes_identical = 0;
 	int bytes_rendered = 0;
 
+	mutex_lock(&dlfb->render_mutex);
+
 	if (!fb_defio)
-		return;
+		goto unlock_ret;
 
 	if (!atomic_read(&dlfb->usb_active))
-		return;
+		goto unlock_ret;
 
 	start_cycles = get_cycles();
 
 	urb = dlfb_get_urb(dlfb);
 	if (!urb)
-		return;
+		goto unlock_ret;
 
 	cmd = urb->transfer_buffer;
 
@@ -782,6 +839,8 @@ error:
 	atomic_add(((unsigned int) ((end_cycles - start_cycles)
 		    >> 10)), /* Kcycles */
 		   &dlfb->cpu_kcycles_used);
+unlock_ret:
+	mutex_unlock(&dlfb->render_mutex);
 }
 
 static int dlfb_get_edid(struct dlfb_data *dlfb, char *edid, int len)
@@ -859,8 +918,7 @@ static int dlfb_ops_ioctl(struct fb_info *info, unsigned int cmd,
 		if (area.y > info->var.yres)
 			area.y = info->var.yres;
 
-		dlfb_handle_damage(dlfb, area.x, area.y, area.w, area.h,
-			   info->screen_base);
+		dlfb_handle_damage(dlfb, area.x, area.y, area.w, area.h);
 	}
 
 	return 0;
@@ -942,6 +1000,10 @@ static void dlfb_ops_destroy(struct fb_info *info)
 {
 	struct dlfb_data *dlfb = info->par;
 
+	cancel_work_sync(&dlfb->damage_work);
+
+	mutex_destroy(&dlfb->render_mutex);
+
 	if (info->cmap.len != 0)
 		fb_dealloc_cmap(&info->cmap);
 	if (info->monspecs.modedb)
@@ -1065,8 +1127,7 @@ static int dlfb_ops_set_par(struct fb_info *info)
 			pix_framebuffer[i] = 0x37e6;
 	}
 
-	dlfb_handle_damage(dlfb, 0, 0, info->var.xres, info->var.yres,
-			   info->screen_base);
+	dlfb_handle_damage(dlfb, 0, 0, info->var.xres, info->var.yres);
 
 	return 0;
 }
@@ -1639,6 +1700,11 @@ static int dlfb_usb_probe(struct usb_interface *intf,
 	dlfb->ops = dlfb_ops;
 	info->fbops = &dlfb->ops;
 
+	mutex_init(&dlfb->render_mutex);
+	dlfb_init_damage(dlfb);
+	spin_lock_init(&dlfb->damage_lock);
+	INIT_WORK(&dlfb->damage_work, dlfb_damage_work);
+
 	INIT_LIST_HEAD(&info->modelist);
 
 	if (!dlfb_alloc_urb_list(dlfb, WRITES_IN_FLIGHT, MAX_TRANSFER)) {