diff options
| author | Fancy Fang <chen.fang@freescale.com> | 2015-06-08 15:22:48 +0800 |
|---|---|---|
| committer | Nitin Garg <nitin.garg@freescale.com> | 2015-09-17 09:23:36 -0500 |
| commit | a93a93862c0afb70b2dd14e6d284b4a98ebf1538 (patch) | |
| tree | 1f16ec35d47ec087884af30881aae8b90308cdc9 /drivers/dma | |
| parent | 1dc25d9fdebfe4ee284cd85649ba4fcbc840a39d (diff) | |
MLK-11067 dma: pxp-v3: replace a mutex with a semaphore to avoid deadlock
The 'mutex_unlock()' function should not be called in interrupt
handler, since this may cause deadlock issue. So using semaphore
to replace the 'hard_lock' mutex.
Signed-off-by: Fancy Fang <chen.fang@freescale.com>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/pxp/pxp_dma_v3.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/drivers/dma/pxp/pxp_dma_v3.c b/drivers/dma/pxp/pxp_dma_v3.c index 5501031b01f1..5b021ff75570 100644 --- a/drivers/dma/pxp/pxp_dma_v3.c +++ b/drivers/dma/pxp/pxp_dma_v3.c @@ -34,6 +34,7 @@ #include <linux/of_gpio.h> #include <linux/platform_device.h> #include <linux/pm_runtime.h> +#include <linux/semaphore.h> #include <linux/slab.h> #include <linux/vmalloc.h> #include <linux/dmaengine.h> @@ -79,7 +80,6 @@ void __iomem *pinctrl_base; static LIST_HEAD(head); static int timeout_in_ms = 600; static unsigned int block_size; -static struct mutex hard_lock; static struct pxp_collision_info col_info; struct pxp_dma { @@ -110,6 +110,7 @@ struct pxps { /* to turn clock off when pxp is inactive */ struct timer_list clk_timer; + struct semaphore sema; }; #define to_pxp_dma(d) container_of(d, struct pxp_dma, dma) @@ -1692,7 +1693,7 @@ static irqreturn_t pxp_irq(int irq, void *dev_id) list_move(&desc->list, &pxp_chan->free_list); spin_unlock_irqrestore(&pxp_chan->lock, flags0); - mutex_unlock(&hard_lock); + up(&pxp->sema); pxp->pxp_ongoing = 0; mod_timer(&pxp->clk_timer, jiffies + msecs_to_jiffies(timeout_in_ms)); @@ -1825,7 +1826,7 @@ static void pxp_issue_pending(struct dma_chan *chan) spin_unlock_irqrestore(&pxp->lock, flags0); pxp_clk_enable(pxp); - mutex_lock(&hard_lock); + down(&pxp->sema); spin_lock_irqsave(&pxp->lock, flags); pxp->pxp_ongoing = 1; @@ -4308,7 +4309,7 @@ static int pxp_probe(struct platform_device *pdev) spin_lock_init(&pxp->lock); mutex_init(&pxp->clk_mutex); - mutex_init(&hard_lock); + sema_init(&pxp->sema, 1); pxp->base = devm_request_and_ioremap(&pdev->dev, res); if (pxp->base == NULL) { |