[PATCH 1/2] spi/pl022: timeout on polled transfer v2

[grant.likely@secretlab.ca (Grant Likely)]

On Thu, May 19, 2011 at 06:05:34PM +0200, Linus Walleij wrote:
> From: Magnus Templing <magnus.templing@stericsson.com>
> 
> This adds the missing handling of polling timeouts and deletes
> our last todo.
> 
> Signed-off-by: Magnus Templing <magnus.templing@stericsson.com>
> Reviewed-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
> [Fixups from review by Wolfram Sang]
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Applied, thanks.

g.

> ---
>  drivers/spi/amba-pl022.c |   23 +++++++++++++++--------
>  1 files changed, 15 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/spi/amba-pl022.c b/drivers/spi/amba-pl022.c
> index 08de58e..18667de 100644
> --- a/drivers/spi/amba-pl022.c
> +++ b/drivers/spi/amba-pl022.c
> @@ -24,11 +24,6 @@
>   * GNU General Public License for more details.
>   */
>  
> -/*
> - * TODO:
> - * - add timeout on polled transfers
> - */
> -
>  #include <linux/init.h>
>  #include <linux/module.h>
>  #include <linux/device.h>
> @@ -287,6 +282,8 @@
>  
>  #define CLEAR_ALL_INTERRUPTS  0x3
>  
> +#define SPI_POLLING_TIMEOUT 1000
> +
>  
>  /*
>   * The type of reading going on on this chip
> @@ -1378,6 +1375,7 @@ static void do_polling_transfer(struct pl022 *pl022)
>  	struct spi_transfer *transfer = NULL;
>  	struct spi_transfer *previous = NULL;
>  	struct chip_data *chip;
> +	unsigned long time, timeout;
>  
>  	chip = pl022->cur_chip;
>  	message = pl022->cur_msg;
> @@ -1415,9 +1413,18 @@ static void do_polling_transfer(struct pl022 *pl022)
>  		       SSP_CR1(pl022->virtbase));
>  
>  		dev_dbg(&pl022->adev->dev, "polling transfer ongoing ...\n");
> -		/* FIXME: insert a timeout so we don't hang here indefinitely */
> -		while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end)
> +
> +		timeout = jiffies + msecs_to_jiffies(SPI_POLLING_TIMEOUT);
> +		while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end) {
> +			time = jiffies;
>  			readwriter(pl022);
> +			if (time_after(time, timeout)) {
> +				dev_warn(&pl022->adev->dev,
> +				"%s: timeout!\n", __func__);
> +				message->state = STATE_ERROR;
> +				goto out;
> +			}
> +		}
>  
>  		/* Update total byte transferred */
>  		message->actual_length += pl022->cur_transfer->len;
> @@ -1426,7 +1433,7 @@ static void do_polling_transfer(struct pl022 *pl022)
>  		/* Move to next transfer */
>  		message->state = next_transfer(pl022);
>  	}
> -
> +out:
>  	/* Handle end of message */
>  	if (message->state == STATE_DONE)
>  		message->status = 0;
> -- 
> 1.7.3.2
>