[PATCH V2] i2c-imx: do not allow interruptions when waiting for I2C to complete
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From: Marc Kleine-Budde on 27 May 2010 08:20 The i2c_imx_trx_complete() function is using wait_event_interruptible_timeout() to wait for the I2C controller to signal that it has completed an I2C bus operation. If the process that causes the I2C operation receives a signal, the wait will be interrupted, returning an error. It is better to let the I2C operation finished before handling the signal (i.e. returning into userspace). It is safe to use wait_event_timeout() instead, because the timeout will allow the process to exit if the I2C bus hangs. It's also better to allow the I2C operation to finish, because unacknowledged I2C operations can cause the I2C bus to hang. Signed-off-by: Marc Kleine-Budde <mkl(a)pengutronix.de> Reviewed-by: Wolfram Sang <w.sang(a)pengutronix.de> --- V2: Remove check for "result < 0" as commented by Wolfram Sang. drivers/i2c/busses/i2c-imx.c | 9 +++------ 1 files changed, 3 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index d1ff940..58df809 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -161,13 +161,10 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx) { int result; - result = wait_event_interruptible_timeout(i2c_imx->queue, + result = wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10); - if (unlikely(result < 0)) { - dev_dbg(&i2c_imx->adapter.dev, "<%s> result < 0\n", __func__); - return result; - } else if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) { + if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) { dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__); return -ETIMEDOUT; } @@ -295,7 +292,7 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id) i2c_imx->i2csr = temp; temp &= ~I2SR_IIF; writeb(temp, i2c_imx->base + IMX_I2C_I2SR); - wake_up_interruptible(&i2c_imx->queue); + wake_up(&i2c_imx->queue); return IRQ_HANDLED; } -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |