diff options
| author |   Jens Taprogge <jens.taprogge@taprogge.org> | 2012-09-12 14:55:33 +0200 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-09-12 09:56:01 -0700 |
| commit | 487e0a608d8d7483be5b5fe3fe9414636c087588 (patch) | |
| tree | 0721268c17b01a3edcf8a8ef1641021a5bed144b /drivers/staging/ipack | |
| parent | Staging: ipack/bridges/tpci200: RCU protect slot_irq pointers. (diff) | |
| download | linux-dev-487e0a608d8d7483be5b5fe3fe9414636c087588.tar.xz linux-dev-487e0a608d8d7483be5b5fe3fe9414636c087588.zip | |
Staging: ipack/bridges/tpci200: Protect device registers with spinlock.
Some of the device registers are accessed from both interrupt and
non-interrupt context. To ensure proper read-modify-write modification
of these registers we can not use the "global" tpci200 mutex. Instead
a spin-lock is used.
Signed-off-by: Jens Taprogge <jens.taprogge@taprogge.org>
Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/ipack')
| -rw-r--r-- | drivers/staging/ipack/bridges/tpci200.c | 33 | ||||
| -rw-r--r-- | drivers/staging/ipack/bridges/tpci200.h | 1 |
2 files changed, 15 insertions, 19 deletions
diff --git a/drivers/staging/ipack/bridges/tpci200.c b/drivers/staging/ipack/bridges/tpci200.c index 9ce577ab9437..b1ddbe3ec33a 100644 --- a/drivers/staging/ipack/bridges/tpci200.c +++ b/drivers/staging/ipack/bridges/tpci200.c @@ -53,30 +53,22 @@ static struct tpci200_board *check_slot(struct ipack_device *dev) return tpci200; } -static void __tpci200_clear_mask(__le16 __iomem *addr, u16 mask) -{ - iowrite16(ioread16(addr) & (~mask), addr); -} - static void tpci200_clear_mask(struct tpci200_board *tpci200, __le16 __iomem *addr, u16 mask) { - mutex_lock(&tpci200->mutex); - __tpci200_clear_mask(addr, mask); - mutex_unlock(&tpci200->mutex); -} - -static void __tpci200_set_mask(__le16 __iomem *addr, u16 mask) -{ - iowrite16(ioread16(addr) | mask, addr); + unsigned long flags; + spin_lock_irqsave(&tpci200->regs_lock, flags); + iowrite16(ioread16(addr) & (~mask), addr); + spin_unlock_irqrestore(&tpci200->regs_lock, flags); } static void tpci200_set_mask(struct tpci200_board *tpci200, __le16 __iomem *addr, u16 mask) { - mutex_lock(&tpci200->mutex); - __tpci200_set_mask(addr, mask); - mutex_unlock(&tpci200->mutex); + unsigned long flags; + spin_lock_irqsave(&tpci200->regs_lock, flags); + iowrite16(ioread16(addr) | mask, addr); + spin_unlock_irqrestore(&tpci200->regs_lock, flags); } static void tpci200_unregister(struct tpci200_board *tpci200) @@ -143,7 +135,7 @@ static irqreturn_t tpci200_interrupt(int irq, void *dev_id) dev_info(&tpci200->info->pdev->dev, "No registered ISR for slot [%d:%d]!. IRQ will be disabled.\n", tpci200->number, i); - __tpci200_clear_mask( + tpci200_clear_mask(tpci200, &tpci200->info->interface_regs->control[i], TPCI200_INT0_EN | TPCI200_INT1_EN); } @@ -213,6 +205,9 @@ static int tpci200_register(struct tpci200_board *tpci200) TPCI200_MEM8_SPACE_BAR), TPCI200_MEM8_SIZE); + /* Initialize lock that protects interface_regs */ + spin_lock_init(&tpci200->regs_lock); + ioidint_base = pci_resource_start(tpci200->info->pdev, TPCI200_IO_ID_INT_SPACES_BAR); mem_base = pci_resource_start(tpci200->info->pdev, @@ -272,7 +267,7 @@ out_disable_pci: static int __tpci200_request_irq(struct tpci200_board *tpci200, struct ipack_device *dev) { - __tpci200_set_mask( + tpci200_set_mask(tpci200, &tpci200->info->interface_regs->control[dev->slot], TPCI200_INT0_EN | TPCI200_INT1_EN); return 0; @@ -281,7 +276,7 @@ static int __tpci200_request_irq(struct tpci200_board *tpci200, static void __tpci200_free_irq(struct tpci200_board *tpci200, struct ipack_device *dev) { - __tpci200_clear_mask( + tpci200_clear_mask(tpci200, &tpci200->info->interface_regs->control[dev->slot], TPCI200_INT0_EN | TPCI200_INT1_EN); } diff --git a/drivers/staging/ipack/bridges/tpci200.h b/drivers/staging/ipack/bridges/tpci200.h index 75a5dccca992..b8e98268a598 100644 --- a/drivers/staging/ipack/bridges/tpci200.h +++ b/drivers/staging/ipack/bridges/tpci200.h @@ -163,6 +163,7 @@ struct tpci200_infos { struct tpci200_board { unsigned int number; struct mutex mutex; + spinlock_t regs_lock; struct tpci200_slot *slots; struct tpci200_infos *info; }; |