Commit aaaf939c authored by Mike Frysinger's avatar Mike Frysinger Committed by Linus Torvalds

Blackfin SPI Driver: add timeout while waiting for SPIF in dma irq handler

The "while" endless loop will cause the system hang if hardware error, so
we add timeout control to make the system alive.
Signed-off-by: default avatarMike Frysinger <vapier.adi@gmail.com>
Signed-off-by: default avatarBryan Wu <cooloney@kernel.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 11d6f599
...@@ -557,6 +557,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id) ...@@ -557,6 +557,7 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
struct driver_data *drv_data = dev_id; struct driver_data *drv_data = dev_id;
struct chip_data *chip = drv_data->cur_chip; struct chip_data *chip = drv_data->cur_chip;
struct spi_message *msg = drv_data->cur_msg; struct spi_message *msg = drv_data->cur_msg;
unsigned long timeout;
unsigned short dmastat = get_dma_curr_irqstat(drv_data->dma_channel); unsigned short dmastat = get_dma_curr_irqstat(drv_data->dma_channel);
u16 spistat = read_STAT(drv_data); u16 spistat = read_STAT(drv_data);
...@@ -582,8 +583,17 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id) ...@@ -582,8 +583,17 @@ static irqreturn_t dma_irq_handler(int irq, void *dev_id)
cpu_relax(); cpu_relax();
} }
dev_dbg(&drv_data->pdev->dev,
"in dma_irq_handler dmastat:0x%x spistat:0x%x\n",
dmastat, read_STAT(drv_data));
timeout = jiffies + HZ;
while (!(read_STAT(drv_data) & SPIF)) while (!(read_STAT(drv_data) & SPIF))
cpu_relax(); if (!time_before(jiffies, timeout)) {
dev_warn(&drv_data->pdev->dev, "timeout waiting for SPIF");
break;
} else
cpu_relax();
if ((dmastat & DMA_ERR) && (spistat & RBSY)) { if ((dmastat & DMA_ERR) && (spistat & RBSY)) {
msg->state = ERROR_STATE; msg->state = ERROR_STATE;
......
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