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| author | Sascha Hauer <s.hauer@pengutronix.de> | 2011-08-25 11:03:35 +0200 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2011-08-29 20:08:26 +0530 |
| commit | 73eab978ad6934499b83ecc920d470fe99c5e54d (patch) | |
| tree | 1f622269c883e767832a365557c2c504a3fd2fc3 /drivers/dma | |
| parent | 981ed70d8e4faf3689dbf3c48868a31d5b004d7a (diff) | |
| download | linux-73eab978ad6934499b83ecc920d470fe99c5e54d.tar.gz linux-73eab978ad6934499b83ecc920d470fe99c5e54d.tar.bz2 linux-73eab978ad6934499b83ecc920d470fe99c5e54d.zip | |
dmaengine i.MX SDMA: lock channel 0
channel0 of the sdma engine is the configuration channel. It
is a shared resource and thus must be protected by a mutex.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/imx-sdma.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index 7bd7e98548cd..f50c87c303dd 100644 --- a/drivers/dma/imx-sdma.c +++ b/drivers/dma/imx-sdma.c @@ -318,6 +318,7 @@ struct sdma_engine { dma_addr_t context_phys; struct dma_device dma_device; struct clk *clk; + struct mutex channel_0_lock; struct sdma_script_start_addrs *script_addrs; }; @@ -415,11 +416,15 @@ static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size, dma_addr_t buf_phys; int ret; + mutex_lock(&sdma->channel_0_lock); + buf_virt = dma_alloc_coherent(NULL, size, &buf_phys, GFP_KERNEL); - if (!buf_virt) - return -ENOMEM; + if (!buf_virt) { + ret = -ENOMEM; + goto err_out; + } bd0->mode.command = C0_SETPM; bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD; @@ -433,6 +438,9 @@ static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size, dma_free_coherent(NULL, size, buf_virt, buf_phys); +err_out: + mutex_unlock(&sdma->channel_0_lock); + return ret; } @@ -656,6 +664,8 @@ static int sdma_load_context(struct sdma_channel *sdmac) dev_dbg(sdma->dev, "event_mask0 = 0x%08x\n", sdmac->event_mask0); dev_dbg(sdma->dev, "event_mask1 = 0x%08x\n", sdmac->event_mask1); + mutex_lock(&sdma->channel_0_lock); + memset(context, 0, sizeof(*context)); context->channel_state.pc = load_address; @@ -676,6 +686,8 @@ static int sdma_load_context(struct sdma_channel *sdmac) ret = sdma_run_channel(&sdma->channel[0]); + mutex_unlock(&sdma->channel_0_lock); + return ret; } @@ -1274,6 +1286,8 @@ static int __init sdma_probe(struct platform_device *pdev) if (!sdma) return -ENOMEM; + mutex_init(&sdma->channel_0_lock); + sdma->dev = &pdev->dev; iores = platform_get_resource(pdev, IORESOURCE_MEM, 0); |