rng driver update

Linus, please do a

bk pull bk://kernel.bkbits.net/jgarzik/random-2.5

This will update the following files:

 Documentation/i810_rng.txt     |  134 ------
 drivers/char/amd768_rng.c      |  295 --------------
 drivers/char/i810_rng.c        |  404 -------------------
 Documentation/hw_random.txt    |  134 ++++++
 arch/i386/kernel/cpu/centaur.c |   47 +-
 arch/i386/kernel/cpu/common.c  |    5 
 arch/i386/kernel/cpu/proc.c    |   15 
 drivers/char/Kconfig           |   37 -
 drivers/char/Makefile          |    3 
 drivers/char/hw_random.c       |  846 +++++++++++++++++++++++++++++++++++------
 include/asm-i386/cpufeature.h  |   10 
 include/asm-i386/msr.h         |    1 
 12 files changed, 940 insertions(+), 991 deletions(-)

through these ChangeSets:

<[email protected]> (03/03/13 1.1109)
[hw_random] fixes and cleanups

* s/Via/VIA/
* allow multiple simultaneous open(2)s of the chrdev. This allows us to eliminate some code, without modifying the core code (rng_dev_read) at all.
* s/__exit// in ->cleanup ops, to eliminate link error

<[email protected]> (03/03/13 1.1108)
[hw_random] add support for VIA Nehemiah RNG ("xstore" instruction)

<[email protected]> (03/03/13 1.1107)
[ia32] cpu capabilities cleanups and additions

* Add support for new Centaur(VIA) and Intel cpuid feature bits, expanding the x86_capability array by two.
* (cleanup) Move cpu setup for newer Via C3 cpus into its own

     function, init_c3()

* Add support for RNG control msr on VIA Nehemiah
* export X86_FEATURE_XSTORE and cpu_has_xstore macros so that kernel code may easily test for cpu support of the new "xstore" instruction.

<[email protected]> (03/03/13 1.1106)
[hw_random] update amd768_rng driver to be modular; add Intel support

Take Alan's amd768_rng driver, recently renamed to hw_random.c, and convert it's very-simple structure to support multiple types of hardware RNG. Integrate Intel i8xx (ICH) RNG support.

<[email protected]> (03/03/13 1.1105)
[hw_random] shuffle files in preparation for hw_random driver update

Delete drivers/char/i810_rng.c, superceded. Rename Doc/i810_rng.txt to Doc/hw_random.txt. Rename drv/char/amd768_rng.c to drv/char/hw_random.c.

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1104 -> 1.1105
# drivers/char/amd768_rng.c 1.3 -> 1.4 drivers/char/hw_random.c (moved)
# drivers/char/i810_rng.c 1.13 -> (deleted)
# Documentation/i810_rng.txt 1.6 -> 1.7 Documentation/hw_random.txt (moved)
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/03/13 [email protected] 1.1105
# [hw_random] shuffle files in preparation for hw_random driver update #
# Delete drivers/char/i810_rng.c, superceded.
# Rename Doc/i810_rng.txt to Doc/hw_random.txt.
# Rename drv/char/amd768_rng.c to drv/char/hw_random.c.
# --------------------------------------------
#

diff -Nru a/Documentation/hw_random.txt b/Documentation/hw_random.txt
@@ -0,0 +1,134 @@
+	Hardware driver for Intel i810 Random Number Generator (RNG)
+	Copyright 2000,2001 Jeff Garzik <[email protected]>
+	Copyright 2000,2001 Philipp Rumpf <[email protected]>
+
+Introduction:
+
+	The i810_rng device driver is software that makes use of a
+	special hardware feature on the Intel i8xx-based chipsets,
+	a Random Number Generator (RNG).
+
+	In order to make effective use of this device driver, you
+	should download the support software as well.  Download the
+	latest version of the "intel-rng-tools" package from the
+	i810_rng driver's official Web site:
+
+		http://sourceforge.net/projects/gkernel/
+
+About the Intel RNG hardware, from the firmware hub datasheet:
+
+	The Firmware Hub integrates a Random Number Generator (RNG)
+	using thermal noise generated from inherently random quantum
+	mechanical properties of silicon. When not generating new random
+	bits the RNG circuitry will enter a low power state. Intel will
+	provide a binary software driver to give third party software
+	access to our RNG for use as a security feature. At this time,
+	the RNG is only to be used with a system in an OS-present state.
+
+Theory of operation:
+
+	Character driver.  Using the standard open()
+	and read() system calls, you can read random data from
+	the i810 RNG device.  This data is NOT CHECKED by any
+	fitness tests, and could potentially be bogus (if the
+	hardware is faulty or has been tampered with).  Data is only
+	output if the hardware "has-data" flag is set, but nevertheless
+	a security-conscious person would run fitness tests on the
+	data before assuming it is truly random.
+
+	/dev/intel_rng is char device major 10, minor 183.
+
+Driver notes:
+
+	* FIXME: support poll(2)
+
+	NOTE: request_mem_region was removed, for two reasons:
+	1) Only one RNG is supported by this driver, 2) The location
+	used by the RNG is a fixed location in MMIO-addressable memory,
+	3) users with properly working BIOS e820 handling will always
+	have the region in which the RNG is located reserved, so
+	request_mem_region calls always fail for proper setups.
+	However, for people who use mem=XX, BIOS e820 information is
+	-not- in /proc/iomem, and request_mem_region(RNG_ADDR) can
+	succeed.
+
+Driver details:
+
+	Based on:
+	Intel 82802AB/82802AC Firmware Hub (FWH) Datasheet
+		May 1999 Order Number: 290658-002 R
+
+	Intel 82802 Firmware Hub: Random Number Generator
+	Programmer's Reference Manual
+		December 1999 Order Number: 298029-001 R
+
+	Intel 82802 Firmware HUB Random Number Generator Driver
+	Copyright (c) 2000 Matt Sottek <[email protected]>
+
+	Special thanks to Matt Sottek.  I did the "guts", he
+	did the "brains" and all the testing.
+
+Change history:
+
+	Version 0.9.8:
+	* Support other i8xx chipsets by adding 82801E detection
+	* 82801DB detection is the same as for 82801CA.
+
+	Version 0.9.7:
+	* Support other i8xx chipsets too (by adding 82801BA(M) and
+	  82801CA(M) detection)
+
+	Version 0.9.6:
+	* Internal driver cleanups, prep for 1.0.0 release.
+
+	Version 0.9.5:
+	* Rip out entropy injection via timer.  It never ever worked,
+	  and a better solution (rngd) is now available.
+
+	Version 0.9.4:
+	* Fix: Remove request_mem_region
+	* Fix: Horrible bugs in FIPS calculation and test execution
+
+	Version 0.9.3:
+	* Clean up rng_read a bit.
+	* Update i810_rng driver Web site URL.
+	* Increase default timer interval to 4 samples per second.
+	* Abort if mem region is not available.
+	* BSS zero-initialization cleanup.
+	* Call misc_register() from rng_init_one.
+	* Fix O_NONBLOCK to occur before we schedule.
+
+	Version 0.9.2:
+	* Simplify open blocking logic
+
+	Version 0.9.1:
+	* Support i815 chipsets too (Matt Sottek)
+	* Fix reference counting when statically compiled (prumpf)
+	* Rewrite rng_dev_read (prumpf)
+	* Make module races less likely (prumpf)
+	* Small miscellaneous bug fixes (prumpf)
+	* Use pci table for PCI id list
+
+	Version 0.9.0:
+	* Don't register a pci_driver, because we are really
+	  using PCI bridge vendor/device ids, and someone
+	  may want to register a driver for the bridge. (bug fix)
+	* Don't let the usage count go negative (bug fix)
+	* Clean up spinlocks (bug fix)
+	* Enable PCI device, if necessary (bug fix)
+	* iounmap on module unload (bug fix)
+	* If RNG chrdev is already in use when open(2) is called,
+	  sleep until it is available.
+	* Remove redundant globals rng_allocated, rng_use_count
+	* Convert numeric globals to unsigned
+	* Module unload cleanup
+
+	Version 0.6.2:
+	* Clean up spinlocks.  Since we don't have any interrupts
+	  to worry about, but we do have a timer to worry about,
+	  we use spin_lock_bh everywhere except the timer function
+	  itself.
+	* Fix module load/unload.
+	* Fix timer function and h/w enable/disable logic
+	* New timer interval sysctl
+	* Clean up sysctl names

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1105 -> 1.1106
# drivers/char/Kconfig 1.8 -> 1.9
# drivers/char/hw_random.c 1.4 -> 1.5
# drivers/char/Makefile 1.55 -> 1.56
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/03/13 [email protected] 1.1106
# [hw_random] update amd768_rng driver to be modular; add Intel support #
# Take Alan's amd768_rng driver, recently renamed to hw_random.c,

# and convert it's very-simple structure to support multiple
# types of hardware RNG.  Integrate Intel i8xx (ICH) RNG support.
# --------------------------------------------
#
diff -Nru a/drivers/char/Kconfig b/drivers/char/Kconfig
--- a/drivers/char/Kconfig	Thu Mar 13 18:52:44 2003
+++ b/drivers/char/Kconfig	Thu Mar 13 18:52:44 2003
@@ -709,39 +709,20 @@

If you're not sure, say N.

-config INTEL_RNG
- tristate "Intel i8x0 Random Number Generator support"
+config HW_RANDOM
+ tristate "Intel/AMD H/W Random Number Generator support"
depends on (X86 || IA64) && PCI
---help---
This driver provides kernel-side support for the Random Number

-	  Generator hardware found on Intel i8xx-based motherboards.
+	  Generator hardware found on Intel i8xx-based motherboards,
+	  and AMD 76x-based motherboards.

-	  Both a character driver, used to read() entropy data, and a timer
-	  function which automatically adds entropy directly into the
-	  kernel pool, are exported by this driver.
+	  Provides a character driver, used to read() entropy data.

To compile this driver as a module ( = code which can be inserted in and removed from the running kernel whenever you want), say M here and read <file:Documentation/modules.txt>. The module will be called
- i810_rng.
-
- If unsure, say N.
-
-config AMD_RNG
- tristate "AMD 768 Random Number Generator support"
- depends on X86 && PCI
- ---help---
- This driver provides kernel-side support for the Random Number
- Generator hardware found on AMD 76x based motherboards.
-

-	  Both a character driver, used to read() entropy data, and a timer
-	  function which automatically adds entropy directly into the
-	  kernel pool, are exported by this driver.
-
-	  To compile this driver as a module ( = code which can be inserted in
-	  and removed from the running kernel whenever you want), say M here
-	  and read <file:Documentation/modules.txt>. The module will be called
-	  amd768_rng.
+	  hw_random.

If unsure, say N.

diff -Nru a/drivers/char/Makefile b/drivers/char/Makefile
@@ -59,8 +59,7 @@
 obj-$(CONFIG_TOSHIBA) += toshiba.o
 obj-$(CONFIG_I8K) += i8k.o
 obj-$(CONFIG_DS1620) += ds1620.o
-obj-$(CONFIG_INTEL_RNG) += i810_rng.o
-obj-$(CONFIG_AMD_RNG) += amd768_rng.o
+obj-$(CONFIG_HW_RANDOM) += hw_random.o
 obj-$(CONFIG_QIC02_TAPE) += tpqic02.o
 obj-$(CONFIG_FTAPE) += ftape/
 obj-$(CONFIG_H8) += h8.o

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1106 -> 1.1107
# include/asm-i386/msr.h 1.12 -> 1.13
# arch/i386/kernel/cpu/common.c 1.19 -> 1.20
# arch/i386/kernel/cpu/centaur.c 1.6 -> 1.7
# include/asm-i386/cpufeature.h 1.6 -> 1.7
# arch/i386/kernel/cpu/proc.c 1.8 -> 1.9
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/03/13 [email protected] 1.1107
# [ia32] cpu capabilities cleanups and additions
#
# * Add support for new Centaur(VIA) and Intel cpuid feature bits,
# expanding the x86_capability array by two.
# * (cleanup) Move cpu setup for newer Via C3 cpus into its own
# function, init_c3()
# * Add support for RNG control msr on VIA Nehemiah
# * export X86_FEATURE_XSTORE and cpu_has_xstore macros so that
# kernel code may easily test for cpu support of the new
# "xstore" instruction.
# --------------------------------------------
#

diff -Nru a/arch/i386/kernel/cpu/centaur.c b/arch/i386/kernel/cpu/centaur.c
@@ -248,6 +248,37 @@
 }
 #endif
 
+static void __init init_c3(struct cpuinfo_x86 *c)
+{
+	u32  lo, hi;
+
+	/* Test for Centaur Extended Feature Flags presence */
+	if (cpuid_eax(0xC0000000) >= 0xC0000001) {
+		/* store Centaur Extended Feature Flags as
+		 * word 5 of the CPU capability bit array
+		 */
+		c->x86_capability[5] = cpuid_edx(0xC0000001);
+	}
+
+	switch (c->x86_model) {
+		case 6 ... 8:		/* Cyrix III family */
+			rdmsr (MSR_VIA_FCR, lo, hi);
+			lo |= (1<<1 | 1<<7);	/* Report CX8 & enable PGE */
+			wrmsr (MSR_VIA_FCR, lo, hi);
+
+			set_bit(X86_FEATURE_CX8, c->x86_capability);
+			set_bit(X86_FEATURE_3DNOW, c->x86_capability);
+
+			/* fall through */
+
+		case 9:	/* Nehemiah */
+		default:
+			get_model_name(c);
+			display_cacheinfo(c);
+			break;
+	}
+}
+
 static void __init init_centaur(struct cpuinfo_x86 *c)
 {
 	enum {

@@ -386,21 +417,7 @@
 			break;
 
 		case 6:
-			switch (c->x86_model) {
-				case 6 ... 8:		/* Cyrix III family */
-					rdmsr (MSR_VIA_FCR, lo, hi);
-					lo |= (1<<1 | 1<<7);	/* Report CX8 & enable PGE */
-					wrmsr (MSR_VIA_FCR, lo, hi);
-
-					set_bit(X86_FEATURE_CX8, c->x86_capability);
-					set_bit(X86_FEATURE_3DNOW, c->x86_capability);
-
-				case 9:	/* Nehemiah */
-				default:
-					get_model_name(c);
-					display_cacheinfo(c);
-					break;
-			}
+			init_c3(c);
 			break;
 	}
 }

diff -Nru a/arch/i386/kernel/cpu/common.c b/arch/i386/kernel/cpu/common.c
@@ -211,9 +211,10 @@
 	
 		/* Intel-defined flags: level 0x00000001 */
 		if ( c->cpuid_level >= 0x00000001 ) {
-			u32 capability;
-			cpuid(0x00000001, &tfms, &junk, &junk, &capability);
+			u32 capability, excap;
+			cpuid(0x00000001, &tfms, &junk, &excap, &capability);
 			c->x86_capability[0] = capability;
+			c->x86_capability[4] = excap;
 			c->x86 = (tfms >> 8) & 15;
 			c->x86_model = (tfms >> 4) & 15;
 			c->x86_mask = tfms & 15;

diff -Nru a/arch/i386/kernel/cpu/proc.c b/arch/i386/kernel/cpu/proc.c
@@ -37,7 +37,20 @@
 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 
 		/* Other (Linux-defined) */
-		"cxmmx", "k6_mtrr", "cyrix_arr", "centaur_mcr", NULL, NULL, NULL, NULL,
+		"cxmmx", "k6_mtrr", "cyrix_arr", "centaur_mcr",
+		NULL, NULL, NULL, NULL,
+		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+
+		/* Intel-defined (#2) */
+		"pni", NULL, NULL, "monitor", "ds_cpl", NULL, NULL, NULL,
+		"tm2", NULL, "cnxt_id", NULL, NULL, NULL, NULL, NULL,
+		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
+
+		/* VIA/Cyrix/Centaur-defined */
+		NULL, NULL, "xstore", NULL, NULL, NULL, NULL, NULL,
 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
 		NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,

diff -Nru a/include/asm-i386/cpufeature.h b/include/asm-i386/cpufeature.h
@@ -9,9 +9,9 @@
 
 #include <linux/bitops.h>
 
-#define NCAPINTS	4	/* Currently we have 4 32-bit words worth of info */
+#define NCAPINTS	6	/* Currently we have 6 32-bit words worth of info */
 
-/* Intel-defined CPU features, CPUID level 0x00000001, word 0 */
+/* Intel-defined CPU features, CPUID level 0x00000001 (edx), word 0 */
 #define X86_FEATURE_FPU		(0*32+ 0) /* Onboard FPU */
 #define X86_FEATURE_VME		(0*32+ 1) /* Virtual Mode Extensions */
 #define X86_FEATURE_DE		(0*32+ 2) /* Debugging Extensions */

@@ -64,6 +64,11 @@
 #define X86_FEATURE_CYRIX_ARR	(3*32+ 2) /* Cyrix ARRs (= MTRRs) */
 #define X86_FEATURE_CENTAUR_MCR	(3*32+ 3) /* Centaur MCRs (= MTRRs) */
 
+/* Intel-defined CPU features, CPUID level 0x00000001 (ecx), word 4 */
+
+/* VIA/Cyrix/Centaur-defined CPU features, CPUID level 0xC0000001, word 5 */
+#define X86_FEATURE_XSTORE	(5*32+ 2) /* on-CPU RNG present (xstore insn) */
+
 
 #define cpu_has(c, bit)		test_bit(bit, (c)->x86_capability)
 #define boot_cpu_has(bit)	test_bit(bit, boot_cpu_data.x86_capability)

@@ -87,6 +92,7 @@
 #define cpu_has_k6_mtrr		boot_cpu_has(X86_FEATURE_K6_MTRR)
 #define cpu_has_cyrix_arr	boot_cpu_has(X86_FEATURE_CYRIX_ARR)
 #define cpu_has_centaur_mcr	boot_cpu_has(X86_FEATURE_CENTAUR_MCR)
+#define cpu_has_xstore		boot_cpu_has(X86_FEATURE_XSTORE)
 
 #endif /* __ASM_I386_CPUFEATURE_H */
 

diff -Nru a/include/asm-i386/msr.h b/include/asm-i386/msr.h
@@ -218,6 +218,7 @@
 /* VIA Cyrix defined MSRs*/
 #define MSR_VIA_FCR			0x1107
 #define MSR_VIA_LONGHAUL		0x110a
+#define MSR_VIA_RNG			0x110b
 #define MSR_VIA_BCR2			0x1147
 
 /* Transmeta defined MSRs */

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1107 -> 1.1108
# drivers/char/Kconfig 1.9 -> 1.10
# drivers/char/hw_random.c 1.5 -> 1.6
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/03/13 [email protected] 1.1108
# [hw_random] add support for VIA Nehemiah RNG ("xstore" instruction) # --------------------------------------------
#

diff -Nru a/drivers/char/Kconfig b/drivers/char/Kconfig
@@ -710,7 +710,7 @@
 	  If you're not sure, say N.
 
 config HW_RANDOM
-	tristate "Intel/AMD H/W Random Number Generator support"
+	tristate "Intel/AMD/Via H/W Random Number Generator support"
 	depends on (X86 || IA64) && PCI
 	---help---
 	  This driver provides kernel-side support for the Random Number

# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher. # This patch includes the following deltas:
# ChangeSet 1.1108 -> 1.1109
# drivers/char/Kconfig 1.10 -> 1.11
# drivers/char/hw_random.c 1.6 -> 1.7
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/03/13 [email protected] 1.1109
# [hw_random] fixes and cleanups
#
# * s/Via/VIA/
# * allow multiple simultaneous open(2)s of the chrdev. This allows

# us to eliminate some code, without modifying the core code (rng_dev_read)
# at all.
# * s/__exit// in ->cleanup ops, to eliminate link error
# --------------------------------------------
#
diff -Nru a/drivers/char/Kconfig b/drivers/char/Kconfig
--- a/drivers/char/Kconfig	Thu Mar 13 18:53:15 2003
+++ b/drivers/char/Kconfig	Thu Mar 13 18:53:15 2003
@@ -710,12 +710,12 @@
 	  If you're not sure, say N.

config HW_RANDOM
- tristate "Intel/AMD/Via H/W Random Number Generator support"
+ tristate "Intel/AMD/VIA HW Random Number Generator support"
depends on (X86 || IA64) && PCI
---help---
This driver provides kernel-side support for the Random Number Generator hardware found on Intel i8xx-based motherboards,
- and AMD 76x-based motherboards.
+ AMD 76x-based motherboards, and Via Nehemiah CPUs.

Provides a character driver, used to read() entropy data.

diff -Nru a/drivers/char/hw_random.c b/drivers/char/hw_random.c
@@ -1,5 +1,5 @@
 /*
- 	Hardware driver for the Intel/AMD/Via Random Number Generators (RNG)
+ 	Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
 	(c) Copyright 2003 Red Hat Inc <[email protected]>
  
  	derived from

@@ -79,22 +79,21 @@
 #define RNG_MISCDEV_MINOR		183 /* official */
 
 static int rng_dev_open (struct inode *inode, struct file *filp);
-static int rng_dev_release (struct inode *inode, struct file *filp);
 static ssize_t rng_dev_read (struct file *filp, char *buf, size_t size,
 			     loff_t * offp);
 
 static int __init intel_init (struct pci_dev *dev);
-static void __exit intel_cleanup(void);
+static void intel_cleanup(void);
 static unsigned int intel_data_present (void);
 static u32 intel_data_read (void);
 
 static int __init amd_init (struct pci_dev *dev);
-static void __exit amd_cleanup(void);
+static void amd_cleanup(void);
 static unsigned int amd_data_present (void);
 static u32 amd_data_read (void);
 
 static int __init via_init(struct pci_dev *dev);
-static void __exit via_cleanup(void);
+static void via_cleanup(void);
 static unsigned int via_data_present (void);
 static u32 via_data_read (void);
 

@@ -107,12 +106,9 @@
 };
 static struct rng_operations *rng_ops;
 
-static struct semaphore rng_open_sem;	/* Semaphore for serializing rng_open/release */
-
 static struct file_operations rng_chrdev_ops = {
 	.owner		= THIS_MODULE,
 	.open		= rng_dev_open,
-	.release	= rng_dev_release,
 	.read		= rng_dev_read,
 };
 

@@ -262,7 +258,7 @@
 	return rc;
 }
 
-static void __exit intel_cleanup(void)
+static void intel_cleanup(void)
 {
 	u8 hw_status;
 

@@ -333,7 +329,7 @@
 	return rc;
 }
 
-static void __exit amd_cleanup(void)
+static void amd_cleanup(void)
 {
 	u8 rnen;
 

@@ -346,7 +342,7 @@
 
 /***********************************************************************
  *
- * Via RNG operations
+ * VIA RNG operations
  *
  */
 

@@ -448,14 +444,14 @@
 	   unneeded */
 	rdmsr(MSR_VIA_RNG, lo, hi);
 	if ((lo & VIA_RNG_ENABLE) == 0) {
-		printk(KERN_ERR PFX "cannot enable Via C3 RNG, aborting\n");
+		printk(KERN_ERR PFX "cannot enable VIA C3 RNG, aborting\n");
 		return -ENODEV;
 	}
 
 	return 0;
 }
 
-static void __exit via_cleanup(void)
+static void via_cleanup(void)
 {
 	u32 lo, hi;
 

@@ -473,26 +469,12 @@
 
 static int rng_dev_open (struct inode *inode, struct file *filp)
 {
+	/* enforce read-only access to this chrdev */
 	if ((filp->f_mode & FMODE_READ) == 0)
 		return -EINVAL;
 	if (filp->f_mode & FMODE_WRITE)
 		return -EINVAL;
 
-	/* wait for device to become free */
-	if (filp->f_flags & O_NONBLOCK) {
-		if (down_trylock (&rng_open_sem))
-			return -EAGAIN;
-	} else {
-		if (down_interruptible (&rng_open_sem))
-			return -ERESTARTSYS;
-	}
-	return 0;
-}
-
-
-static int rng_dev_release (struct inode *inode, struct file *filp)
-{
-	up(&rng_open_sem);
 	return 0;
 }
 

@@ -595,8 +577,6 @@
 
 	DPRINTK ("ENTER\n");
 
-	init_MUTEX (&rng_open_sem);
-
 	/* Probe for Intel, AMD RNGs */
 	pci_for_each_dev(pdev) {
 		ent = pci_match_device (rng_pci_tbl, pdev);

@@ -607,7 +587,7 @@
 	}
 
 #ifdef __i386__
-	/* Probe for Via RNG */
+	/* Probe for VIA RNG */
 	if (cpu_has_xstore) {
 		rng_ops = &rng_vendor_ops[rng_hw_via];
 		pdev = NULL;