Merge branch 'fbdev/udlfb'

9 files changed, 64 insertions, 365 deletions

diff --git a/drivers/staging/Kconfig b/drivers/staging/Kconfig
index 5eafdf435550..df31a7228079 100644
--- a/drivers/staging/Kconfig
+++ b/drivers/staging/Kconfig
@@ -111,8 +111,6 @@ source "drivers/staging/vt6655/Kconfig"
 
 source "drivers/staging/vt6656/Kconfig"
 
-source "drivers/staging/udlfb/Kconfig"
-
 source "drivers/staging/hv/Kconfig"
 
 source "drivers/staging/vme/Kconfig"
diff --git a/drivers/staging/Makefile b/drivers/staging/Makefile
index a97a955c094b..7a15c0c82b69 100644
--- a/drivers/staging/Makefile
+++ b/drivers/staging/Makefile
@@ -38,7 +38,6 @@ obj-$(CONFIG_USB_SERIAL_QUATECH_USB2)	+= quatech_usb2/
 obj-$(CONFIG_OCTEON_ETHERNET)	+= octeon/
 obj-$(CONFIG_VT6655)		+= vt6655/
 obj-$(CONFIG_VT6656)		+= vt6656/
-obj-$(CONFIG_FB_UDL)		+= udlfb/
 obj-$(CONFIG_HYPERV)		+= hv/
 obj-$(CONFIG_VME_BUS)		+= vme/
 obj-$(CONFIG_MRST_RAR_HANDLER)	+= memrar/
diff --git a/drivers/staging/udlfb/Kconfig b/drivers/staging/udlfb/Kconfig
deleted file mode 100644
index 65bd5db4ca56..000000000000
--- a/drivers/staging/udlfb/Kconfig
+++ /dev/null
@@ -1,14 +0,0 @@
-config FB_UDL
-	tristate "Displaylink USB Framebuffer support"
-	depends on FB && USB
-	select FB_MODE_HELPERS
-	select FB_SYS_FILLRECT
-	select FB_SYS_COPYAREA
-	select FB_SYS_IMAGEBLIT
-	select FB_SYS_FOPS
-	select FB_DEFERRED_IO
-	---help---
-	  This is a kernel framebuffer driver for DisplayLink USB devices.
-	  Supports fbdev clients like xf86-video-fbdev, kdrive, fbi, and
-	  mplayer -vo fbdev. Supports all USB 2.0 era DisplayLink devices.
-	  To compile as a module, choose M here: the module name is udlfb.
diff --git a/drivers/staging/udlfb/Makefile b/drivers/staging/udlfb/Makefile
deleted file mode 100644
index 30d9e675b10f..000000000000
--- a/drivers/staging/udlfb/Makefile
+++ /dev/null
@@ -1 +0,0 @@
-obj-$(CONFIG_FB_UDL)		+= udlfb.o
diff --git a/drivers/staging/udlfb/udlfb.h b/drivers/staging/udlfb/udlfb.h
deleted file mode 100644
index 6f9785e9d62e..000000000000
--- a/drivers/staging/udlfb/udlfb.h
+++ /dev/null
@@ -1,117 +0,0 @@
-#ifndef UDLFB_H
-#define UDLFB_H
-
-/*
- * TODO: Propose standard fb.h ioctl for reporting damage,
- * using _IOWR() and one of the existing area structs from fb.h
- * Consider these ioctls deprecated, but they're still used by the
- * DisplayLink X server as yet - need both to be modified in tandem
- * when new ioctl(s) are ready.
- */
-#define DLFB_IOCTL_RETURN_EDID	 0xAD
-#define DLFB_IOCTL_REPORT_DAMAGE 0xAA
-struct dloarea {
-	int x, y;
-	int w, h;
-	int x2, y2;
-};
-
-struct urb_node {
-	struct list_head entry;
-	struct dlfb_data *dev;
-	struct delayed_work release_urb_work;
-	struct urb *urb;
-};
-
-struct urb_list {
-	struct list_head list;
-	spinlock_t lock;
-	struct semaphore limit_sem;
-	int available;
-	int count;
-	size_t size;
-};
-
-struct dlfb_data {
-	struct usb_device *udev;
-	struct device *gdev; /* &udev->dev */
-	struct fb_info *info;
-	struct urb_list urbs;
-	struct kref kref;
-	char *backing_buffer;
-	int fb_count;
-	bool virtualized; /* true when physical usb device not present */
-	struct delayed_work free_framebuffer_work;
-	atomic_t usb_active; /* 0 = update virtual buffer, but no usb traffic */
-	atomic_t lost_pixels; /* 1 = a render op failed. Need screen refresh */
-	char *edid; /* null until we read edid from hw or get from sysfs */
-	size_t edid_size;
-	int sku_pixel_limit;
-	int base16;
-	int base8;
-	u32 pseudo_palette[256];
-	/* blit-only rendering path metrics, exposed through sysfs */
-	atomic_t bytes_rendered; /* raw pixel-bytes driver asked to render */
-	atomic_t bytes_identical; /* saved effort with backbuffer comparison */
-	atomic_t bytes_sent; /* to usb, after compression including overhead */
-	atomic_t cpu_kcycles_used; /* transpired during pixel processing */
-};
-
-#define NR_USB_REQUEST_I2C_SUB_IO 0x02
-#define NR_USB_REQUEST_CHANNEL 0x12
-
-/* -BULK_SIZE as per usb-skeleton. Can we get full page and avoid overhead? */
-#define BULK_SIZE 512
-#define MAX_TRANSFER (PAGE_SIZE*16 - BULK_SIZE)
-#define WRITES_IN_FLIGHT (4)
-
-#define MIN_EDID_SIZE 128
-#define MAX_EDID_SIZE 128
-
-#define MAX_VENDOR_DESCRIPTOR_SIZE 256
-
-#define GET_URB_TIMEOUT	HZ
-#define FREE_URB_TIMEOUT (HZ*2)
-
-#define BPP                     2
-#define MAX_CMD_PIXELS		255
-
-#define RLX_HEADER_BYTES	7
-#define MIN_RLX_PIX_BYTES       4
-#define MIN_RLX_CMD_BYTES	(RLX_HEADER_BYTES + MIN_RLX_PIX_BYTES)
-
-#define RLE_HEADER_BYTES	6
-#define MIN_RLE_PIX_BYTES	3
-#define MIN_RLE_CMD_BYTES	(RLE_HEADER_BYTES + MIN_RLE_PIX_BYTES)
-
-#define RAW_HEADER_BYTES	6
-#define MIN_RAW_PIX_BYTES	2
-#define MIN_RAW_CMD_BYTES	(RAW_HEADER_BYTES + MIN_RAW_PIX_BYTES)
-
-#define DL_DEFIO_WRITE_DELAY    5 /* fb_deferred_io.delay in jiffies */
-#define DL_DEFIO_WRITE_DISABLE  (HZ*60) /* "disable" with long delay */
-
-/* remove these once align.h patch is taken into kernel */
-#define DL_ALIGN_UP(x, a) ALIGN(x, a)
-#define DL_ALIGN_DOWN(x, a) ALIGN(x-(a-1), a)
-
-/* remove once this gets added to sysfs.h */
-#define __ATTR_RW(attr) __ATTR(attr, 0644, attr##_show, attr##_store)
-
-/*
- * udlfb is both a usb device, and a framebuffer device.
- * They may exist at the same time, but during various stages
- * inactivity, teardown, or "virtual" operation, only one or the
- * other will exist (one will outlive the other).  So we can't
- * call the dev_*() macros, because we don't have a stable dev object.
- */
-#define dl_err(format, arg...) \
-	pr_err("udlfb: " format, ## arg)
-#define dl_warn(format, arg...) \
-	pr_warning("udlfb: " format, ## arg)
-#define dl_notice(format, arg...) \
-	pr_notice("udlfb: " format, ## arg)
-#define dl_info(format, arg...) \
-	pr_info("udlfb: " format, ## arg)
-
-#endif
diff --git a/drivers/staging/udlfb/udlfb.txt b/drivers/staging/udlfb/udlfb.txt
deleted file mode 100644
index 7fdde2a02a27..000000000000
--- a/drivers/staging/udlfb/udlfb.txt
+++ /dev/null
@@ -1,144 +0,0 @@
-
-What is udlfb?
-===============
-
-This is a driver for DisplayLink USB 2.0 era graphics chips.
-
-DisplayLink chips provide simple hline/blit operations with some compression,
-pairing that with a hardware framebuffer (16MB) on the other end of the
-USB wire.  That hardware framebuffer is able to drive the VGA, DVI, or HDMI
-monitor with no CPU involvement until a pixel has to change.
-
-The CPU or other local resource does all the rendering; optinally compares the
-result with a local shadow of the remote hardware framebuffer to identify
-the minimal set of pixels that have changed; and compresses and sends those
-pixels line-by-line via USB bulk transfers.
-
-Because of the efficiency of bulk transfers and a protocol on top that
-does not require any acks - the effect is very low latency that
-can support surprisingly high resolutions with good performance for
-non-gaming and non-video applications.
-
-Mode setting, EDID read, etc are other bulk or control transfers. Mode
-setting is very flexible - able to set nearly arbitrary modes from any timing.
-
-Advantages of USB graphics in general:
-
- * Ability to add a nearly arbitrary number of displays to any USB 2.0
-   capable system. On Linux, number of displays is limited by fbdev interface
-   (FB_MAX is currently 32). Of course, all USB devices on the same
-   host controller share the same 480Mbs USB 2.0 interface.
-
-Advantages of supporting DisplayLink chips with kernel framebuffer interface:
-
- * The actual hardware functionality of DisplayLink chips matches nearly
-   one-to-one with the fbdev interface, making the driver quite small and
-   tight relative to the functionality it provides.
- * X servers and other applications can use the standard fbdev interface
-   from user mode to talk to the device, without needing to know anything
-   about USB or DisplayLink's protocol at all. A "displaylink" X driver
-   and a slightly modified "fbdev" X driver are among those that already do.
-
-Disadvantages:
-
- * Fbdev's mmap interface assumes a real hardware framebuffer is mapped.
-   In the case of USB graphics, it is just an allocated (virtual) buffer.
-   Writes need to be detected and encoded into USB bulk transfers by the CPU.
-   Accurate damage/changed area notifications work around this problem.
-   In the future, hopefully fbdev will be enhanced with an small standard
-   interface to allow mmap clients to report damage, for the benefit
-   of virtual or remote framebuffers.
- * Fbdev does not arbitrate client ownership of the framebuffer well.
- * Fbcon assumes the first framebuffer it finds should be consumed for console.
- * It's not clear what the future of fbdev is, given the rise of KMS/DRM.
-
-How to use it?
-==============
-
-Udlfb, when loaded as a module, will match against all USB 2.0 generation
-DisplayLink chips (Alex and Ollie family). It will then attempt to read the EDID
-of the monitor, and set the best common mode between the DisplayLink device
-and the monitor's capabilities.
-
-If the DisplayLink device is successful, it will paint a "green screen" which
-means that from a hardware and fbdev software perspective, everything is good.
-
-At that point, a /dev/fb? interface will be present for user-mode applications
-to open and begin writing to the framebuffer of the DisplayLink device using
-standard fbdev calls.  Note that if mmap() is used, by default the user mode
-application must send down damage notifcations to trigger repaints of the
-changed regions.  Alternatively, udlfb can be recompiled with experimental
-defio support enabled, to support a page-fault based detection mechanism
-that can work without explicit notifcation.
-
-The most common client of udlfb is xf86-video-displaylink or a modified
-xf86-video-fbdev X server. These servers have no real DisplayLink specific
-code. They write to the standard framebuffer interface and rely on udlfb
-to do its thing.  The one extra feature they have is the ability to report
-rectangles from the X DAMAGE protocol extension down to udlfb via udlfb's
-damage interface (which will hopefully be standardized for all virtual
-framebuffers that need damage info). These damage notifications allow
-udlfb to efficiently process the changed pixels.
-
-Module Options
-==============
-
-Special configuration for udlfb is usually unnecessary. There are a few
-options, however.
-
-From the command line, pass options to modprobe
-modprobe udlfb defio=1 console=1
-
-Or for permanent option, create file like /etc/modprobe.d/options with text
-options udlfb defio=1 console=1
-
-Accepted options:
-
-fb_defio	Make use of the fb_defio (CONFIG_FB_DEFERRED_IO) kernel
-		module to track changed areas of the framebuffer by page faults.
-        	Standard fbdev applications that use mmap but that do not
-		report damage, may be able to work with this enabled.
-		Disabled by default because of overhead and other issues.
-
-console		Allow fbcon to attach to udlfb provided framebuffers. This
-		is disabled by default because fbcon will aggressively consume
-		the first framebuffer it finds, which isn't usually what the
-		user wants in the case of USB displays.
-
-Sysfs Attributes
-================
-
-Udlfb creates several files in /sys/class/graphics/fb?
-Where ? is the sequential framebuffer id of the particular DisplayLink device
-
-edid	       		If a valid EDID blob is written to this file (typically
-			by a udev rule), then udlfb will use this EDID as a
-			backup in case reading the actual EDID of the monitor
-			attached to the DisplayLink device fails. This is
-			especially useful for fixed panels, etc. that cannot
-			communicate their capabilities via EDID. Reading
-			this file returns the current EDID of the attached
-			monitor (or last backup value written). This is
-			useful to get the EDID of the attached monitor,
-			which can be passed to utilities like parse-edid.
-
-metrics_bytes_rendered	32-bit count of pixel bytes rendered
-
-metrics_bytes_identical 32-bit count of how many of those bytes were found to be
-			unchanged, based on a shadow framebuffer check
-
-metrics_bytes_sent	32-bit count of how many bytes were transferred over
-			USB to communicate the resulting changed pixels to the
-			hardware. Includes compression and protocol overhead
-
-metrics_cpu_kcycles_used 32-bit count of CPU cycles used in processing the
-			above pixels (in thousands of cycles).
-
-metrics_reset		Write-only. Any write to this file resets all metrics
-			above to zero.  Note that the 32-bit counters above
-			roll over very quickly. To get reliable results, design
-			performance tests to start and finish in a very short
-			period of time (one minute or less is safe).
-
---
-Bernie Thompson <bernie@plugable.com>
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index fdddf58bdaf5..9f36a29b10b4 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -2116,6 +2116,20 @@ config FB_SM501
 
 	  If unsure, say N.
 
+config FB_UDL
+	tristate "Displaylink USB Framebuffer support"
+	depends on FB && USB
+	select FB_MODE_HELPERS
+	select FB_SYS_FILLRECT
+	select FB_SYS_COPYAREA
+	select FB_SYS_IMAGEBLIT
+	select FB_SYS_FOPS
+	select FB_DEFERRED_IO
+	---help---
+	  This is a kernel framebuffer driver for DisplayLink USB devices.
+	  Supports fbdev clients like xf86-video-fbdev, kdrive, fbi, and
+	  mplayer -vo fbdev. Supports all USB 2.0 era DisplayLink devices.
+	  To compile as a module, choose M here: the module name is udlfb.
 
 config FB_PNX4008_DUM
 	tristate "Display Update Module support on Philips PNX4008 board"
diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index bdf626419433..f9de51c39ad7 100644
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -125,6 +125,7 @@ obj-$(CONFIG_FB_PNX4008_DUM_RGB)  += pnx4008/
 obj-$(CONFIG_FB_IBM_GXT4500)	  += gxt4500.o
 obj-$(CONFIG_FB_PS3)		  += ps3fb.o
 obj-$(CONFIG_FB_SM501)            += sm501fb.o
+obj-$(CONFIG_FB_UDL)		  += udlfb.o
 obj-$(CONFIG_FB_XILINX)           += xilinxfb.o
 obj-$(CONFIG_SH_MIPI_DSI)	  += sh_mipi_dsi.o
 obj-$(CONFIG_FB_SH_MOBILE_HDMI)	  += sh_mobile_hdmi.o
diff --git a/drivers/staging/udlfb/udlfb.c b/drivers/video/udlfb.c
index b7ac16005265..020589a6bf02 100644
--- a/drivers/staging/udlfb/udlfb.c
+++ b/drivers/video/udlfb.c
@@ -16,6 +16,8 @@
  * from Florian Echtler, Henrik Bjerregaard Pedersen, and others.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
@@ -26,8 +28,8 @@
 #include <linux/vmalloc.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
-
-#include "udlfb.h"
+#include <video/udlfb.h>
+#include "edid.h"
 
 static struct fb_fix_screeninfo dlfb_fix = {
 	.id =           "udlfb",
@@ -40,9 +42,7 @@ static struct fb_fix_screeninfo dlfb_fix = {
 };
 
 static const u32 udlfb_info_flags = FBINFO_DEFAULT | FBINFO_READS_FAST |
-#ifdef FBINFO_VIRTFB
 		FBINFO_VIRTFB |
-#endif
 		FBINFO_HWACCEL_IMAGEBLIT | FBINFO_HWACCEL_FILLRECT |
 		FBINFO_HWACCEL_COPYAREA | FBINFO_MISC_ALWAYS_SETPAR;
 
@@ -293,7 +293,7 @@ static int dlfb_ops_mmap(struct fb_info *info, struct vm_area_struct *vma)
 
 	pos = (unsigned long)info->fix.smem_start + offset;
 
-	dl_notice("mmap() framebuffer addr:%lu size:%lu\n",
+	pr_notice("mmap() framebuffer addr:%lu size:%lu\n",
 		  pos, size);
 
 	while (size > 0) {
@@ -595,18 +595,6 @@ error:
 	return 0;
 }
 
-static ssize_t dlfb_ops_read(struct fb_info *info, char __user *buf,
-			 size_t count, loff_t *ppos)
-{
-	ssize_t result = -ENOSYS;
-
-#if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE
-	result = fb_sys_read(info, buf, count, ppos);
-#endif
-
-	return result;
-}
-
 /*
  * Path triggered by usermode clients who write to filesystem
  * e.g. cat filename > /dev/fb1
@@ -616,12 +604,10 @@ static ssize_t dlfb_ops_read(struct fb_info *info, char __user *buf,
 static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
 			  size_t count, loff_t *ppos)
 {
-	ssize_t result = -ENOSYS;
+	ssize_t result;
 	struct dlfb_data *dev = info->par;
 	u32 offset = (u32) *ppos;
 
-#if defined CONFIG_FB_SYS_FOPS || defined CONFIG_FB_SYS_FOPS_MODULE
-
 	result = fb_sys_write(info, buf, count, ppos);
 
 	if (result > 0) {
@@ -632,7 +618,6 @@ static ssize_t dlfb_ops_write(struct fb_info *info, const char __user *buf,
 		dlfb_handle_damage(dev, 0, start, info->var.xres,
 			lines, info->screen_base);
 	}
-#endif
 
 	return result;
 }
@@ -644,14 +629,10 @@ static void dlfb_ops_copyarea(struct fb_info *info,
 
 	struct dlfb_data *dev = info->par;
 
-#if defined CONFIG_FB_SYS_COPYAREA || defined CONFIG_FB_SYS_COPYAREA_MODULE
-
 	sys_copyarea(info, area);
 
 	dlfb_handle_damage(dev, area->dx, area->dy,
 			area->width, area->height, info->screen_base);
-#endif
-
 }
 
 static void dlfb_ops_imageblit(struct fb_info *info,
@@ -659,15 +640,10 @@ static void dlfb_ops_imageblit(struct fb_info *info,
 {
 	struct dlfb_data *dev = info->par;
 
-#if defined CONFIG_FB_SYS_IMAGEBLIT || defined CONFIG_FB_SYS_IMAGEBLIT_MODULE
-
 	sys_imageblit(info, image);
 
 	dlfb_handle_damage(dev, image->dx, image->dy,
 			image->width, image->height, info->screen_base);
-
-#endif
-
 }
 
 static void dlfb_ops_fillrect(struct fb_info *info,
@@ -675,17 +651,12 @@ static void dlfb_ops_fillrect(struct fb_info *info,
 {
 	struct dlfb_data *dev = info->par;
 
-#if defined CONFIG_FB_SYS_FILLRECT || defined CONFIG_FB_SYS_FILLRECT_MODULE
-
 	sys_fillrect(info, rect);
 
 	dlfb_handle_damage(dev, rect->dx, rect->dy, rect->width,
 			      rect->height, info->screen_base);
-#endif
-
 }
 
-#ifdef CONFIG_FB_DEFERRED_IO
 /*
  * NOTE: fb_defio.c is holding info->fbdefio.mutex
  *   Touching ANY framebuffer memory that triggers a page fault
@@ -747,8 +718,6 @@ error:
 		   &dev->cpu_kcycles_used);
 }
 
-#endif
-
 static int dlfb_get_edid(struct dlfb_data *dev, char *edid, int len)
 {
 	int i;
@@ -765,7 +734,7 @@ static int dlfb_get_edid(struct dlfb_data *dev, char *edid, int len)
 				    (0x80 | (0x02 << 5)), i << 8, 0xA1, rbuf, 2,
 				    HZ);
 		if (ret < 1) {
-			dl_err("Read EDID byte %d failed err %x\n", i, ret);
+			pr_err("Read EDID byte %d failed err %x\n", i, ret);
 			i--;
 			break;
 		}
@@ -881,7 +850,6 @@ static int dlfb_ops_open(struct fb_info *info, int user)
 
 	kref_get(&dev->kref);
 
-#ifdef CONFIG_FB_DEFERRED_IO
 	if (fb_defio && (info->fbdefio == NULL)) {
 		/* enable defio at last moment if not disabled by client */
 
@@ -897,9 +865,8 @@ static int dlfb_ops_open(struct fb_info *info, int user)
 		info->fbdefio = fbdefio;
 		fb_deferred_io_init(info);
 	}
-#endif
 
-	dl_notice("open /dev/fb%d user=%d fb_info=%p count=%d\n",
+	pr_notice("open /dev/fb%d user=%d fb_info=%p count=%d\n",
 	    info->node, user, info, dev->fb_count);
 
 	return 0;
@@ -923,7 +890,7 @@ static void dlfb_free(struct kref *kref)
 
 	kfree(dev->edid);
 
-	dl_warn("freeing dlfb_data %p\n", dev);
+	pr_warn("freeing dlfb_data %p\n", dev);
 
 	kfree(dev);
 }
@@ -959,7 +926,7 @@ static void dlfb_free_framebuffer_work(struct work_struct *work)
 	/* Assume info structure is freed after this point */
 	framebuffer_release(info);
 
-	dl_warn("fb_info for /dev/fb%d has been freed\n", node);
+	pr_warn("fb_info for /dev/fb%d has been freed\n", node);
 
 	/* ref taken in probe() as part of registering framebfufer */
 	kref_put(&dev->kref, dlfb_free);
@@ -978,16 +945,14 @@ static int dlfb_ops_release(struct fb_info *info, int user)
 	if (dev->virtualized && (dev->fb_count == 0))
 		schedule_delayed_work(&dev->free_framebuffer_work, HZ);
 
-#ifdef CONFIG_FB_DEFERRED_IO
 	if ((dev->fb_count == 0) && (info->fbdefio)) {
 		fb_deferred_io_cleanup(info);
 		kfree(info->fbdefio);
 		info->fbdefio = NULL;
 		info->fbops->fb_mmap = dlfb_ops_mmap;
 	}
-#endif
 
-	dl_warn("released /dev/fb%d user=%d count=%d\n",
+	pr_warn("released /dev/fb%d user=%d count=%d\n",
 		  info->node, user, dev->fb_count);
 
 	kref_put(&dev->kref, dlfb_free);
@@ -1005,12 +970,12 @@ static int dlfb_is_valid_mode(struct fb_videomode *mode,
 	struct dlfb_data *dev = info->par;
 
 	if (mode->xres * mode->yres > dev->sku_pixel_limit) {
-		dl_warn("%dx%d beyond chip capabilities\n",
+		pr_warn("%dx%d beyond chip capabilities\n",
 		       mode->xres, mode->yres);
 		return 0;
 	}
 
-	dl_info("%dx%d valid mode\n", mode->xres, mode->yres);
+	pr_info("%dx%d valid mode\n", mode->xres, mode->yres);
 
 	return 1;
 }
@@ -1054,7 +1019,7 @@ static int dlfb_ops_set_par(struct fb_info *info)
 	u16 *pix_framebuffer;
 	int i;
 
-	dl_notice("set_par mode %dx%d\n", info->var.xres, info->var.yres);
+	pr_notice("set_par mode %dx%d\n", info->var.xres, info->var.yres);
 
 	result = dlfb_set_video_mode(dev, &info->var);
 
@@ -1104,7 +1069,7 @@ static int dlfb_ops_blank(int blank_mode, struct fb_info *info)
 
 static struct fb_ops dlfb_ops = {
 	.owner = THIS_MODULE,
-	.fb_read = dlfb_ops_read,
+	.fb_read = fb_sys_read,
 	.fb_write = dlfb_ops_write,
 	.fb_setcolreg = dlfb_ops_setcolreg,
 	.fb_fillrect = dlfb_ops_fillrect,
@@ -1133,7 +1098,7 @@ static int dlfb_realloc_framebuffer(struct dlfb_data *dev, struct fb_info *info)
 	unsigned char *new_fb;
 	unsigned char *new_back;
 
-	dl_warn("Reallocating framebuffer. Addresses will change!\n");
+	pr_warn("Reallocating framebuffer. Addresses will change!\n");
 
 	new_len = info->fix.line_length * info->var.yres;
 
@@ -1143,7 +1108,7 @@ static int dlfb_realloc_framebuffer(struct dlfb_data *dev, struct fb_info *info)
 		 */
 		new_fb = vmalloc(new_len);
 		if (!new_fb) {
-			dl_err("Virtual framebuffer alloc failed\n");
+			pr_err("Virtual framebuffer alloc failed\n");
 			goto error;
 		}
 
@@ -1165,7 +1130,7 @@ static int dlfb_realloc_framebuffer(struct dlfb_data *dev, struct fb_info *info)
 		 */
 		new_back = vmalloc(new_len);
 		if (!new_back)
-			dl_info("No shadow/backing buffer allcoated\n");
+			pr_info("No shadow/backing buffer allcoated\n");
 		else {
 			if (dev->backing_buffer)
 				vfree(dev->backing_buffer);
@@ -1207,7 +1172,7 @@ static int dlfb_setup_modes(struct dlfb_data *dev,
 	if (info->dev) /* only use mutex if info has been registered */
 		mutex_lock(&info->lock);
 
-	edid = kmalloc(MAX_EDID_SIZE, GFP_KERNEL);
+	edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
 	if (!edid) {
 		result = -ENOMEM;
 		goto error;
@@ -1223,9 +1188,9 @@ static int dlfb_setup_modes(struct dlfb_data *dev,
 	 */
 	while (tries--) {
 
-		i = dlfb_get_edid(dev, edid, MAX_EDID_SIZE);
+		i = dlfb_get_edid(dev, edid, EDID_LENGTH);
 
-		if (i >= MIN_EDID_SIZE)
+		if (i >= EDID_LENGTH)
 			fb_edid_to_monspecs(edid, &info->monspecs);
 
 		if (info->monspecs.modedb_len > 0) {
@@ -1238,24 +1203,24 @@ static int dlfb_setup_modes(struct dlfb_data *dev,
 	/* If that fails, use a previously returned EDID if available */
 	if (info->monspecs.modedb_len == 0) {
 
-		dl_err("Unable to get valid EDID from device/display\n");
+		pr_err("Unable to get valid EDID from device/display\n");
 
 		if (dev->edid) {
 			fb_edid_to_monspecs(dev->edid, &info->monspecs);
 			if (info->monspecs.modedb_len > 0)
-				dl_err("Using previously queried EDID\n");
+				pr_err("Using previously queried EDID\n");
 		}
 	}
 
 	/* If that fails, use the default EDID we were handed */
 	if (info->monspecs.modedb_len == 0) {
-		if (default_edid_size >= MIN_EDID_SIZE) {
+		if (default_edid_size >= EDID_LENGTH) {
 			fb_edid_to_monspecs(default_edid, &info->monspecs);
 			if (info->monspecs.modedb_len > 0) {
 				memcpy(edid, default_edid, default_edid_size);
 				dev->edid = edid;
 				dev->edid_size = default_edid_size;
-				dl_err("Using default/backup EDID\n");
+				pr_err("Using default/backup EDID\n");
 			}
 		}
 	}
@@ -1381,7 +1346,7 @@ static ssize_t edid_show(
 	if (off + count > dev->edid_size)
 		count = dev->edid_size - off;
 
-	dl_info("sysfs edid copy %p to %p, %d bytes\n",
+	pr_info("sysfs edid copy %p to %p, %d bytes\n",
 		dev->edid, buf, (int) count);
 
 	memcpy(buf, dev->edid, count);
@@ -1398,15 +1363,13 @@ static ssize_t edid_store(
 	struct dlfb_data *dev = fb_info->par;
 
 	/* We only support write of entire EDID at once, no offset*/
-	if ((src_size < MIN_EDID_SIZE) ||
-	    (src_size > MAX_EDID_SIZE) ||
-	    (src_off != 0))
+	if ((src_size != EDID_LENGTH) || (src_off != 0))
 		return 0;
 
 	dlfb_setup_modes(dev, fb_info, src, src_size);
 
 	if (dev->edid && (memcmp(src, dev->edid, src_size) == 0)) {
-		dl_info("sysfs written EDID is new default\n");
+		pr_info("sysfs written EDID is new default\n");
 		dlfb_ops_set_par(fb_info);
 		return src_size;
 	} else
@@ -1431,7 +1394,7 @@ static ssize_t metrics_reset_store(struct device *fbdev,
 static struct bin_attribute edid_attr = {
 	.attr.name = "edid",
 	.attr.mode = 0666,
-	.size = MAX_EDID_SIZE,
+	.size = EDID_LENGTH,
 	.read = edid_show,
 	.write = edid_store
 };
@@ -1479,7 +1442,7 @@ static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev,
 	total_len = usb_get_descriptor(usbdev, 0x5f, /* vendor specific */
 				    0, desc, MAX_VENDOR_DESCRIPTOR_SIZE);
 	if (total_len > 5) {
-		dl_info("vendor descriptor length:%x data:%02x %02x %02x %02x" \
+		pr_info("vendor descriptor length:%x data:%02x %02x %02x %02x" \
 			"%02x %02x %02x %02x %02x %02x %02x\n",
 			total_len, desc[0],
 			desc[1], desc[2], desc[3], desc[4], desc[5], desc[6],
@@ -1508,7 +1471,7 @@ static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev,
 			case 0x0200: { /* max_area */
 				u32 max_area;
 				max_area = le32_to_cpu(*((u32 *)desc));
-				dl_warn("DL chip limited to %d pixel modes\n",
+				pr_warn("DL chip limited to %d pixel modes\n",
 					max_area);
 				dev->sku_pixel_limit = max_area;
 				break;
@@ -1524,7 +1487,7 @@ static int dlfb_parse_vendor_descriptor(struct dlfb_data *dev,
 
 unrecognized:
 	/* allow udlfb to load for now even if firmware unrecognized */
-	dl_err("Unrecognized vendor firmware descriptor\n");
+	pr_err("Unrecognized vendor firmware descriptor\n");
 
 success:
 	kfree(buf);
@@ -1557,24 +1520,24 @@ static int dlfb_usb_probe(struct usb_interface *interface,
 	dev->gdev = &usbdev->dev; /* our generic struct device * */
 	usb_set_intfdata(interface, dev);
 
-	dl_info("%s %s - serial #%s\n",
+	pr_info("%s %s - serial #%s\n",
 		usbdev->manufacturer, usbdev->product, usbdev->serial);
-	dl_info("vid_%04x&pid_%04x&rev_%04x driver's dlfb_data struct at %p\n",
+	pr_info("vid_%04x&pid_%04x&rev_%04x driver's dlfb_data struct at %p\n",
 		usbdev->descriptor.idVendor, usbdev->descriptor.idProduct,
 		usbdev->descriptor.bcdDevice, dev);
-	dl_info("console enable=%d\n", console);
-	dl_info("fb_defio enable=%d\n", fb_defio);
+	pr_info("console enable=%d\n", console);
+	pr_info("fb_defio enable=%d\n", fb_defio);
 
 	dev->sku_pixel_limit = 2048 * 1152; /* default to maximum */
 
 	if (!dlfb_parse_vendor_descriptor(dev, usbdev)) {
-		dl_err("firmware not recognized. Assume incompatible device\n");
+		pr_err("firmware not recognized. Assume incompatible device\n");
 		goto error;
 	}
 
 	if (!dlfb_alloc_urb_list(dev, WRITES_IN_FLIGHT, MAX_TRANSFER)) {
 		retval = -ENOMEM;
-		dl_err("dlfb_alloc_urb_list failed\n");
+		pr_err("dlfb_alloc_urb_list failed\n");
 		goto error;
 	}
 
@@ -1584,7 +1547,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
 	info = framebuffer_alloc(0, &usbdev->dev);
 	if (!info) {
 		retval = -ENOMEM;
-		dl_err("framebuffer_alloc failed\n");
+		pr_err("framebuffer_alloc failed\n");
 		goto error;
 	}
 
@@ -1595,7 +1558,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
 
 	retval = fb_alloc_cmap(&info->cmap, 256, 0);
 	if (retval < 0) {
-		dl_err("fb_alloc_cmap failed %x\n", retval);
+		pr_err("fb_alloc_cmap failed %x\n", retval);
 		goto error;
 	}
 
@@ -1606,7 +1569,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
 
 	retval = dlfb_setup_modes(dev, info, NULL, 0);
 	if (retval != 0) {
-		dl_err("unable to find common mode for display and adapter\n");
+		pr_err("unable to find common mode for display and adapter\n");
 		goto error;
 	}
 
@@ -1620,7 +1583,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
 
 	retval = register_framebuffer(info);
 	if (retval < 0) {
-		dl_err("register_framebuffer failed %d\n", retval);
+		pr_err("register_framebuffer failed %d\n", retval);
 		goto error;
 	}
 
@@ -1629,7 +1592,7 @@ static int dlfb_usb_probe(struct usb_interface *interface,
 
 	device_create_bin_file(info->dev, &edid_attr);
 
-	dl_info("DisplayLink USB device /dev/fb%d attached. %dx%d resolution."
+	pr_info("DisplayLink USB device /dev/fb%d attached. %dx%d resolution."
 			" Using %dK framebuffer memory\n", info->node,
 			info->var.xres, info->var.yres,
 			((dev->backing_buffer) ?
@@ -1673,7 +1636,7 @@ static void dlfb_usb_disconnect(struct usb_interface *interface)
 	dev = usb_get_intfdata(interface);
 	info = dev->info;
 
-	dl_info("USB disconnect starting\n");
+	pr_info("USB disconnect starting\n");
 
 	/* we virtualize until all fb clients release. Then we free */
 	dev->virtualized = true;
@@ -1737,7 +1700,7 @@ static void dlfb_urb_completion(struct urb *urb)
 		if (!(urb->status == -ENOENT ||
 		    urb->status == -ECONNRESET ||
 		    urb->status == -ESHUTDOWN)) {
-			dl_err("%s - nonzero write bulk status received: %d\n",
+			pr_err("%s - nonzero write bulk status received: %d\n",
 				__func__, urb->status);
 			atomic_set(&dev->lost_pixels, 1);
 		}
@@ -1769,7 +1732,7 @@ static void dlfb_free_urb_list(struct dlfb_data *dev)
 	int ret;
 	unsigned long flags;
 
-	dl_notice("Waiting for completes and freeing all render urbs\n");
+	pr_notice("Waiting for completes and freeing all render urbs\n");
 
 	/* keep waiting and freeing, until we've got 'em all */
 	while (count--) {
@@ -1848,7 +1811,7 @@ static int dlfb_alloc_urb_list(struct dlfb_data *dev, int count, size_t size)
 	dev->urbs.count = i;
 	dev->urbs.available = i;
 
-	dl_notice("allocated %d %d byte urbs\n", i, (int) size);
+	pr_notice("allocated %d %d byte urbs\n", i, (int) size);
 
 	return i;
 }
@@ -1865,7 +1828,7 @@ static struct urb *dlfb_get_urb(struct dlfb_data *dev)
 	ret = down_timeout(&dev->urbs.limit_sem, GET_URB_TIMEOUT);
 	if (ret) {
 		atomic_set(&dev->lost_pixels, 1);
-		dl_warn("wait for urb interrupted: %x available: %d\n",
+		pr_warn("wait for urb interrupted: %x available: %d\n",
 		       ret, dev->urbs.available);
 		goto error;
 	}
@@ -1897,7 +1860,7 @@ static int dlfb_submit_urb(struct dlfb_data *dev, struct urb *urb, size_t len)
 	if (ret) {
 		dlfb_urb_completion(urb); /* because no one else will */
 		atomic_set(&dev->lost_pixels, 1);
-		dl_err("usb_submit_urb error %x\n", ret);
+		pr_err("usb_submit_urb error %x\n", ret);
 	}
 	return ret;
 }