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Diffstat (limited to 'drivers/pci')
-rw-r--r--drivers/pci/access.c55
1 files changed, 33 insertions, 22 deletions
diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 39bb96b413e..98ddba94b5b 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -133,39 +133,46 @@ PCI_USER_WRITE_CONFIG(dword, u32)
struct pci_vpd_pci22 {
struct pci_vpd base;
- spinlock_t lock; /* controls access to hardware and the flags */
- u8 cap;
+ struct mutex lock;
+ u16 flag;
bool busy;
- bool flag; /* value of F bit to wait for */
+ u8 cap;
};
-/* Wait for last operation to complete */
+/*
+ * Wait for last operation to complete.
+ * This code has to spin since there is no other notification from the PCI
+ * hardware. Since the VPD is often implemented by serial attachment to an
+ * EEPROM, it may take many milliseconds to complete.
+ */
static int pci_vpd_pci22_wait(struct pci_dev *dev)
{
struct pci_vpd_pci22 *vpd =
container_of(dev->vpd, struct pci_vpd_pci22, base);
- u16 flag, status;
- int wait;
+ unsigned long timeout = jiffies + HZ/20 + 2;
+ u16 status;
int ret;
if (!vpd->busy)
return 0;
- flag = vpd->flag ? PCI_VPD_ADDR_F : 0;
- wait = vpd->flag ? 10 : 1000; /* read: 100 us; write: 10 ms */
for (;;) {
- ret = pci_user_read_config_word(dev,
- vpd->cap + PCI_VPD_ADDR,
+ ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR,
&status);
- if (ret < 0)
+ if (ret)
return ret;
- if ((status & PCI_VPD_ADDR_F) == flag) {
+
+ if ((status & PCI_VPD_ADDR_F) == vpd->flag) {
vpd->busy = false;
return 0;
}
- if (wait-- == 0)
+
+ if (time_after(jiffies, timeout))
return -ETIMEDOUT;
- udelay(10);
+ if (fatal_signal_pending(current))
+ return -EINTR;
+ if (!cond_resched())
+ udelay(10);
}
}
@@ -175,7 +182,7 @@ static int pci_vpd_pci22_read(struct pci_dev *dev, int pos, int size,
struct pci_vpd_pci22 *vpd =
container_of(dev->vpd, struct pci_vpd_pci22, base);
u32 val;
- int ret;
+ int ret = 0;
int begin, end, i;
if (pos < 0 || pos > vpd->base.len || size > vpd->base.len - pos)
@@ -183,7 +190,9 @@ static int pci_vpd_pci22_read(struct pci_dev *dev, int pos, int size,
if (size == 0)
return 0;
- spin_lock_irq(&vpd->lock);
+ if (mutex_lock_killable(&vpd->lock))
+ return -EINTR;
+
ret = pci_vpd_pci22_wait(dev);
if (ret < 0)
goto out;
@@ -191,15 +200,16 @@ static int pci_vpd_pci22_read(struct pci_dev *dev, int pos, int size,
pos & ~3);
if (ret < 0)
goto out;
+
vpd->busy = true;
- vpd->flag = 1;
+ vpd->flag = PCI_VPD_ADDR_F;
ret = pci_vpd_pci22_wait(dev);
if (ret < 0)
goto out;
ret = pci_user_read_config_dword(dev, vpd->cap + PCI_VPD_DATA,
&val);
out:
- spin_unlock_irq(&vpd->lock);
+ mutex_unlock(&vpd->lock);
if (ret < 0)
return ret;
@@ -220,7 +230,7 @@ static int pci_vpd_pci22_write(struct pci_dev *dev, int pos, int size,
struct pci_vpd_pci22 *vpd =
container_of(dev->vpd, struct pci_vpd_pci22, base);
u32 val;
- int ret;
+ int ret = 0;
if (pos < 0 || pos > vpd->base.len || pos & 3 ||
size > vpd->base.len - pos || size < 4)
@@ -231,7 +241,8 @@ static int pci_vpd_pci22_write(struct pci_dev *dev, int pos, int size,
val |= ((u8) *buf++) << 16;
val |= ((u32)(u8) *buf++) << 24;
- spin_lock_irq(&vpd->lock);
+ if (mutex_lock_killable(&vpd->lock))
+ return -EINTR;
ret = pci_vpd_pci22_wait(dev);
if (ret < 0)
goto out;
@@ -247,7 +258,7 @@ static int pci_vpd_pci22_write(struct pci_dev *dev, int pos, int size,
vpd->flag = 0;
ret = pci_vpd_pci22_wait(dev);
out:
- spin_unlock_irq(&vpd->lock);
+ mutex_unlock(&vpd->lock);
if (ret < 0)
return ret;
@@ -279,7 +290,7 @@ int pci_vpd_pci22_init(struct pci_dev *dev)
vpd->base.len = PCI_VPD_PCI22_SIZE;
vpd->base.ops = &pci_vpd_pci22_ops;
- spin_lock_init(&vpd->lock);
+ mutex_init(&vpd->lock);
vpd->cap = cap;
vpd->busy = false;
dev->vpd = &vpd->base;