usb: pci-quirks: Minor cleanup for AMD PLL quirk

usb_amd_find_chipset_info() is used for chipset detection for
several quirks. It is strange that its return value indicates
the need for the PLL quirk, which means it is often ignored.
This patch adds a function specifically for checking the PLL
quirk like the other ones. Additionally, rename probe_result to
something more appropriate.

Signed-off-by: Ryan Kennedy <ryan5544@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20190704153529.9429-3-ryan5544@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/ehci-pci.c

@@ -149,7 +149,7 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 		break;
 	case PCI_VENDOR_ID_AMD:
 		/* AMD PLL quirk */
-		if (usb_amd_find_chipset_info())
+		if (usb_amd_quirk_pll_check())
 			ehci->amd_pll_fix = 1;
 		/* AMD8111 EHCI doesn't work, according to AMD errata */
 		if (pdev->device == 0x7463) {
@@ -186,7 +186,7 @@ static int ehci_pci_setup(struct usb_hcd *hcd)
 		break;
 	case PCI_VENDOR_ID_ATI:
 		/* AMD PLL quirk */
-		if (usb_amd_find_chipset_info())
+		if (usb_amd_quirk_pll_check())
 			ehci->amd_pll_fix = 1;
 
 		/*

drivers/usb/host/ohci-pci.c

@@ -152,7 +152,7 @@ static int ohci_quirk_amd700(struct usb_hcd *hcd)
 {
 	struct ohci_hcd *ohci = hcd_to_ohci(hcd);
 
-	if (usb_amd_find_chipset_info())
+	if (usb_amd_quirk_pll_check())
 		ohci->flags |= OHCI_QUIRK_AMD_PLL;
 
 	/* SB800 needs pre-fetch fix */

drivers/usb/host/pci-quirks.c

@@ -132,7 +132,7 @@ static struct amd_chipset_info {
 	struct amd_chipset_type sb_type;
 	int isoc_reqs;
 	int probe_count;
-	int probe_result;
+	bool need_pll_quirk;
 } amd_chipset;
 
 static DEFINE_SPINLOCK(amd_lock);
@@ -201,11 +201,11 @@ void sb800_prefetch(struct device *dev, int on)
 }
 EXPORT_SYMBOL_GPL(sb800_prefetch);
 
-int usb_amd_find_chipset_info(void)
+static void usb_amd_find_chipset_info(void)
 {
 	unsigned long flags;
 	struct amd_chipset_info info;
-	int need_pll_quirk = 0;
+	info.need_pll_quirk = 0;
 
 	spin_lock_irqsave(&amd_lock, flags);
 
@@ -213,7 +213,7 @@ int usb_amd_find_chipset_info(void)
 	if (amd_chipset.probe_count > 0) {
 		amd_chipset.probe_count++;
 		spin_unlock_irqrestore(&amd_lock, flags);
-		return amd_chipset.probe_result;
+		return;
 	}
 	memset(&info, 0, sizeof(info));
 	spin_unlock_irqrestore(&amd_lock, flags);
@@ -224,19 +224,19 @@ int usb_amd_find_chipset_info(void)
 
 	switch (info.sb_type.gen) {
 	case AMD_CHIPSET_SB700:
-		need_pll_quirk = info.sb_type.rev <= 0x3B;
+		info.need_pll_quirk = info.sb_type.rev <= 0x3B;
 		break;
 	case AMD_CHIPSET_SB800:
 	case AMD_CHIPSET_HUDSON2:
 	case AMD_CHIPSET_BOLTON:
-		need_pll_quirk = 1;
+		info.need_pll_quirk = 1;
 		break;
 	default:
-		need_pll_quirk = 0;
+		info.need_pll_quirk = 0;
 		break;
 	}
 
-	if (!need_pll_quirk) {
+	if (!info.need_pll_quirk) {
 		if (info.smbus_dev) {
 			pci_dev_put(info.smbus_dev);
 			info.smbus_dev = NULL;
@@ -259,7 +259,6 @@ int usb_amd_find_chipset_info(void)
 		}
 	}
 
-	need_pll_quirk = info.probe_result = 1;
 	printk(KERN_DEBUG "QUIRK: Enable AMD PLL fix\n");
 
 commit:
@@ -270,7 +269,6 @@ int usb_amd_find_chipset_info(void)
 
 		/* Mark that we where here */
 		amd_chipset.probe_count++;
-		need_pll_quirk = amd_chipset.probe_result;
 
 		spin_unlock_irqrestore(&amd_lock, flags);
 
@@ -283,10 +281,7 @@ int usb_amd_find_chipset_info(void)
 		amd_chipset = info;
 		spin_unlock_irqrestore(&amd_lock, flags);
 	}
-
-	return need_pll_quirk;
 }
-EXPORT_SYMBOL_GPL(usb_amd_find_chipset_info);
 
 int usb_hcd_amd_remote_wakeup_quirk(struct pci_dev *pdev)
 {
@@ -322,6 +317,13 @@ bool usb_amd_prefetch_quirk(void)
 }
 EXPORT_SYMBOL_GPL(usb_amd_prefetch_quirk);
 
+bool usb_amd_quirk_pll_check(void)
+{
+	usb_amd_find_chipset_info();
+	return amd_chipset.need_pll_quirk;
+}
+EXPORT_SYMBOL_GPL(usb_amd_quirk_pll_check);
+
 /*
  * The hardware normally enables the A-link power management feature, which
  * lets the system lower the power consumption in idle states.
@@ -527,7 +529,7 @@ void usb_amd_dev_put(void)
 	amd_chipset.nb_type = 0;
 	memset(&amd_chipset.sb_type, 0, sizeof(amd_chipset.sb_type));
 	amd_chipset.isoc_reqs = 0;
-	amd_chipset.probe_result = 0;
+	amd_chipset.need_pll_quirk = 0;
 
 	spin_unlock_irqrestore(&amd_lock, flags);
 

drivers/usb/host/pci-quirks.h

@@ -5,11 +5,11 @@
 #ifdef CONFIG_USB_PCI
 void uhci_reset_hc(struct pci_dev *pdev, unsigned long base);
 int uhci_check_and_reset_hc(struct pci_dev *pdev, unsigned long base);
-int usb_amd_find_chipset_info(void);
 int usb_hcd_amd_remote_wakeup_quirk(struct pci_dev *pdev);
 bool usb_amd_hang_symptom_quirk(void);
 bool usb_amd_prefetch_quirk(void);
 void usb_amd_dev_put(void);
+bool usb_amd_quirk_pll_check(void);
 void usb_amd_quirk_pll_disable(void);
 void usb_amd_quirk_pll_enable(void);
 void usb_asmedia_modifyflowcontrol(struct pci_dev *pdev);

drivers/usb/host/xhci-pci.c

@@ -130,7 +130,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 		xhci->quirks |= XHCI_AMD_0x96_HOST;
 
 	/* AMD PLL quirk */
-	if (pdev->vendor == PCI_VENDOR_ID_AMD && usb_amd_find_chipset_info())
+	if (pdev->vendor == PCI_VENDOR_ID_AMD && usb_amd_quirk_pll_check())
 		xhci->quirks |= XHCI_AMD_PLL_FIX;
 
 	if (pdev->vendor == PCI_VENDOR_ID_AMD &&