mxc : BUG in imx_dma_request
Martin Fuzzey [Thu, 26 Mar 2009 21:27:52 +0000 (22:27 +0100)]
On MX2 platforms imx_dma_request() calls request_irq() which may sleep
with interrupts disabled.

Signed-off-by: Martin Fuzzey <mfuzzey@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

arch/arm/plat-mxc/dma-mx1-mx2.c

index a9126ed..7764643 100644 (file)
@@ -693,12 +693,15 @@ int imx_dma_request(int channel, const char *name)
                local_irq_restore(flags);
                return -EBUSY;
        }
+       memset(imxdma, 0, sizeof(imxdma));
+       imxdma->name = name;
+       local_irq_restore(flags); /* request_irq() can block */
 
 #ifdef CONFIG_ARCH_MX2
        ret = request_irq(MXC_INT_DMACH0 + channel, dma_irq_handler, 0, "DMA",
                        NULL);
        if (ret) {
-               local_irq_restore(flags);
+               imxdma->name = NULL;
                printk(KERN_CRIT "Can't register IRQ %d for DMA channel %d\n",
                                MXC_INT_DMACH0 + channel, channel);
                return ret;
@@ -708,13 +711,6 @@ int imx_dma_request(int channel, const char *name)
        imxdma->watchdog.data = channel;
 #endif
 
-       imxdma->name = name;
-       imxdma->irq_handler = NULL;
-       imxdma->err_handler = NULL;
-       imxdma->data = NULL;
-       imxdma->sg = NULL;
-
-       local_irq_restore(flags);
        return ret;
 }
 EXPORT_SYMBOL(imx_dma_request);