PCI: Change all drivers to use pci_device->revision

Instead of all drivers reading pci config space to get the revision
ID, they can now use the pci_device->revision member.

This exposes some issues where drivers where reading a word or a dword
for the revision number, and adding useless error-handling around the
read. Some drivers even just read it for no purpose of all.

In devices where the revision ID is being copied over and used in what
appears to be the equivalent of hotpath, I have left the copy code
and the cached copy as not to influence the driver's performance.

Compile tested with make all{yes,mod}config on x86_64 and i386.

Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>
Acked-by: Dave Jones <davej@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/ata/pata_ali.c b/drivers/ata/pata_ali.c
index 30c4276..0104367 100644
--- a/drivers/ata/pata_ali.c
+++ b/drivers/ata/pata_ali.c
@@ -455,23 +455,21 @@
 
 static void ali_init_chipset(struct pci_dev *pdev)
 {
-	u8 rev, tmp;
+	u8 tmp;
 	struct pci_dev *north, *isa_bridge;
 
-	pci_read_config_byte(pdev, PCI_REVISION_ID, &rev);
-
 	/*
 	 * The chipset revision selects the driver operations and
 	 * mode data.
 	 */
 
-	if (rev >= 0x20 && rev < 0xC2) {
+	if (pdev->revision >= 0x20 && pdev->revision < 0xC2) {
 		/* 1543-E/F, 1543C-C, 1543C-D, 1543C-E */
 		pci_read_config_byte(pdev, 0x4B, &tmp);
 		/* Clear CD-ROM DMA write bit */
 		tmp &= 0x7F;
 		pci_write_config_byte(pdev, 0x4B, tmp);
-	} else if (rev >= 0xC2) {
+	} else if (pdev->revision >= 0xC2) {
 		/* Enable cable detection logic */
 		pci_read_config_byte(pdev, 0x4B, &tmp);
 		pci_write_config_byte(pdev, 0x4B, tmp | 0x08);
@@ -483,21 +481,21 @@
 		/* Configure the ALi bridge logic. For non ALi rely on BIOS.
 		   Set the south bridge enable bit */
 		pci_read_config_byte(isa_bridge, 0x79, &tmp);
-		if (rev == 0xC2)
+		if (pdev->revision == 0xC2)
 			pci_write_config_byte(isa_bridge, 0x79, tmp | 0x04);
-		else if (rev > 0xC2 && rev < 0xC5)
+		else if (pdev->revision > 0xC2 && pdev->revision < 0xC5)
 			pci_write_config_byte(isa_bridge, 0x79, tmp | 0x02);
 	}
-	if (rev >= 0x20) {
+	if (pdev->revision >= 0x20) {
 		/*
 		 * CD_ROM DMA on (0x53 bit 0). Enable this even if we want
 		 * to use PIO. 0x53 bit 1 (rev 20 only) - enable FIFO control
 		 * via 0x54/55.
 		 */
 		pci_read_config_byte(pdev, 0x53, &tmp);
-		if (rev <= 0x20)
+		if (pdev->revision <= 0x20)
 			tmp &= ~0x02;
-		if (rev >= 0xc7)
+		if (pdev->revision >= 0xc7)
 			tmp |= 0x03;
 		else
 			tmp |= 0x01;	/* CD_ROM enable for DMA */
@@ -579,25 +577,23 @@
 	};
 
 	const struct ata_port_info *ppi[] = { NULL, NULL };
-	u8 rev, tmp;
+	u8 tmp;
 	struct pci_dev *isa_bridge;
 
-	pci_read_config_byte(pdev, PCI_REVISION_ID, &rev);
-
 	/*
 	 * The chipset revision selects the driver operations and
 	 * mode data.
 	 */
 
-	if (rev < 0x20) {
+	if (pdev->revision < 0x20) {
 		ppi[0] = &info_early;
-	} else if (rev < 0xC2) {
+	} else if (pdev->revision < 0xC2) {
         	ppi[0] = &info_20;
-	} else if (rev == 0xC2) {
+	} else if (pdev->revision == 0xC2) {
         	ppi[0] = &info_c2;
-	} else if (rev == 0xC3) {
+	} else if (pdev->revision == 0xC3) {
         	ppi[0] = &info_c3;
-	} else if (rev == 0xC4) {
+	} else if (pdev->revision == 0xC4) {
         	ppi[0] = &info_c4;
 	} else
         	ppi[0] = &info_c5;
@@ -605,7 +601,7 @@
 	ali_init_chipset(pdev);
 
 	isa_bridge = pci_get_device(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M1533, NULL);
-	if (isa_bridge && rev >= 0x20 && rev < 0xC2) {
+	if (isa_bridge && pdev->revision >= 0x20 && pdev->revision < 0xC2) {
 		/* Are we paired with a UDMA capable chip */
 		pci_read_config_byte(isa_bridge, 0x5E, &tmp);
 		if ((tmp & 0x1E) == 0x12)