[PATCH 44/49] Staging: poch: Fine grained locking

From: Greg KH
Date: Wed Oct 29 2008 - 18:59:55 EST


From: vijaykumar@xxxxxxxxxxxx <vijaykumar@xxxxxxxxxxxx>

Lock only the portion of code that does register access.

Signed-off-by: Vijay Kumar <vijaykumar@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
drivers/staging/poch/poch.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/poch/poch.c b/drivers/staging/poch/poch.c
index 3ecbd7c..1f14792 100644
--- a/drivers/staging/poch/poch.c
+++ b/drivers/staging/poch/poch.c
@@ -485,27 +485,30 @@ static void channel_dma_init(struct channel_info *channel)
/* The DMA address page register is shared between the RX and
* TX channels, so acquire lock.
*/
- spin_lock(channel->iomem_lock);
for (i = 0; i < channel->group_count; i++) {
page = i / 32;
group_in_page = i % 32;

group_reg = group_regs_base + (group_in_page * 4);

+ spin_lock(channel->iomem_lock);
iowrite32(page, fpga + FPGA_DMA_ADR_PAGE_REG);
iowrite32(channel->groups[i].dma_addr, fpga + group_reg);
+ spin_unlock(channel->iomem_lock);
}
+
for (i = 0; i < channel->group_count; i++) {
page = i / 32;
group_in_page = i % 32;

group_reg = group_regs_base + (group_in_page * 4);

+ spin_lock(channel->iomem_lock);
iowrite32(page, fpga + FPGA_DMA_ADR_PAGE_REG);
printk(KERN_INFO PFX "%ld: read dma_addr: 0x%x\n", i,
ioread32(fpga + group_reg));
+ spin_unlock(channel->iomem_lock);
}
- spin_unlock(channel->iomem_lock);

}

--
1.6.0.2

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