spi: sh-msiof: Improve transfer error handling

  - Add a timeout when waiting for the transfer complete interrupt,
  - If sh_msiof_spi_stop() fails, there's no need to clear IER, as the
    interrupt handler has already done that,
  - Propagate transfer failures in sh_msiof_transfer_one().

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@linaro.org>
(cherry picked from commit 75b82e23a4ea20a9e1a48695ff5e01761889dbb3)
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index 2cd5fcb..e5894a6 100644 (file)
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -575,11 +575,16 @@ static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
        ret = sh_msiof_spi_start(p, rx_buf);
        if (ret) {
                dev_err(&p->pdev->dev, "failed to start hardware\n");
-               goto err;
+               goto stop_ier;
        }
 
        /* wait for tx fifo to be emptied / rx fifo to be filled */
-       wait_for_completion(&p->done);
+       ret = wait_for_completion_timeout(&p->done, HZ);
+       if (!ret) {
+               dev_err(&p->pdev->dev, "PIO timeout\n");
+               ret = -ETIMEDOUT;
+               goto stop_reset;
+       }
 
        /* read rx fifo */
        if (rx_buf)
@@ -591,12 +596,15 @@ static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
        ret = sh_msiof_spi_stop(p, rx_buf);
        if (ret) {
                dev_err(&p->pdev->dev, "failed to shut down hardware\n");
-               goto err;
+               return ret;
        }
 
        return words;
 
- err:
+stop_reset:
+       sh_msiof_reset_str(p);
+       sh_msiof_spi_stop(p, rx_buf);
+stop_ier:
        sh_msiof_write(p, IER, 0);
        return ret;
 }
@@ -679,7 +687,7 @@ static int sh_msiof_transfer_one(struct spi_master *master,
                                           rx_buf,
                                           words, bits);
                if (n < 0)
-                       break;
+                       return n;
 
                bytes_done += n * bytes_per_word;
                words -= n;