Merge tag 'pci-v6.14-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

Pull pci fix from Bjorn Helgaas:

 - Save the original INTX_DISABLE bit at the first pcim_intx() call and
   restore that at devres cleanup instead of restoring the opposite of
   the most recent enable/disable pcim_intx() argument, which was wrong
   when a driver called pcim_intx() multiple times or with the already
   enabled state (Takashi Iwai)

* tag 'pci-v6.14-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci:
  PCI: Restore original INTX_DISABLE bit by pcim_intx()

1 files changed, 19 insertions, 15 deletions

diff --git a/drivers/pci/devres.c b/drivers/pci/devres.c
index d1d97a4bb36d..3431a7df3e0d 100644
--- a/drivers/pci/devres.c
+++ b/drivers/pci/devres.c
@@ -419,19 +419,12 @@ static void pcim_intx_restore(struct device *dev, void *data)
 	pci_intx(pdev, res->orig_intx);
 }
 
-static struct pcim_intx_devres *get_or_create_intx_devres(struct device *dev)
+static void save_orig_intx(struct pci_dev *pdev, struct pcim_intx_devres *res)
 {
-	struct pcim_intx_devres *res;
-
-	res = devres_find(dev, pcim_intx_restore, NULL, NULL);
-	if (res)
-		return res;
+	u16 pci_command;
 
-	res = devres_alloc(pcim_intx_restore, sizeof(*res), GFP_KERNEL);
-	if (res)
-		devres_add(dev, res);
-
-	return res;
+	pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
+	res->orig_intx = !(pci_command & PCI_COMMAND_INTX_DISABLE);
 }
 
 /**
@@ -447,12 +440,23 @@ static struct pcim_intx_devres *get_or_create_intx_devres(struct device *dev)
 int pcim_intx(struct pci_dev *pdev, int enable)
 {
 	struct pcim_intx_devres *res;
+	struct device *dev = &pdev->dev;
 
-	res = get_or_create_intx_devres(&pdev->dev);
-	if (!res)
-		return -ENOMEM;
+	/*
+	 * pcim_intx() must only restore the INTx value that existed before the
+	 * driver was loaded, i.e., before it called pcim_intx() for the
+	 * first time.
+	 */
+	res = devres_find(dev, pcim_intx_restore, NULL, NULL);
+	if (!res) {
+		res = devres_alloc(pcim_intx_restore, sizeof(*res), GFP_KERNEL);
+		if (!res)
+			return -ENOMEM;
+
+		save_orig_intx(pdev, res);
+		devres_add(dev, res);
+	}
 
-	res->orig_intx = !enable;
 	pci_intx(pdev, enable);
 
 	return 0;