PCI: switch pci_{enable,disable}_device() to be nestable

[linux-2.6-omap-h63xx.git] / drivers / pci / pci-sysfs.c

diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index f952bfea48a6f972e0a1de9cc8bfc4a33920bfb7..7a94076752d047125d4b72b876afeb28c034a344 100644 (file)
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -42,7 +42,6 @@ pci_config_attr(subsystem_vendor, "0x%04x\n");
 pci_config_attr(subsystem_device, "0x%04x\n");
 pci_config_attr(class, "0x%06x\n");
 pci_config_attr(irq, "%u\n");
-pci_config_attr(is_enabled, "%u\n");
 
 static ssize_t broken_parity_status_show(struct device *dev,
                                         struct device_attribute *attr,
@@ -112,26 +111,36 @@ static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
                       (u8)(pci_dev->class >> 16), (u8)(pci_dev->class >> 8),
                       (u8)(pci_dev->class));
 }
-static ssize_t
-is_enabled_store(struct device *dev, struct device_attribute *attr,
-               const char *buf, size_t count)
+
+static ssize_t is_enabled_store(struct device *dev,
+                               struct device_attribute *attr, const char *buf,
+                               size_t count)
 {
+       ssize_t result = -EINVAL;
        struct pci_dev *pdev = to_pci_dev(dev);
-       int retval = 0;
 
        /* this can crash the machine when done on the "wrong" device */
        if (!capable(CAP_SYS_ADMIN))
                return count;
 
-       if (*buf == '0')
-               pci_disable_device(pdev);
+       if (*buf == '0') {
+               if (atomic_read(&pdev->enable_cnt) != 0)
+                       pci_disable_device(pdev);
+               else
+                       result = -EIO;
+       } else if (*buf == '1')
+               result = pci_enable_device(pdev);
+
+       return result < 0 ? result : count;
+}
 
-       if (*buf == '1')
-               retval = pci_enable_device(pdev);
+static ssize_t is_enabled_show(struct device *dev,
+                              struct device_attribute *attr, char *buf)
+{
+       struct pci_dev *pdev;
 
-       if (retval)
-               return retval;
-       return count;
+       pdev = to_pci_dev (dev);
+       return sprintf (buf, "%u\n", atomic_read(&pdev->enable_cnt));
 }
 
 static ssize_t