diff options
-rw-r--r-- | drivers/pci/access.c | 55 |
1 files changed, 33 insertions, 22 deletions
diff --git a/drivers/pci/access.c b/drivers/pci/access.c index 39bb96b413ef..98ddba94b5b9 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; |