spi: quad: Make DT properties optional

The addition SPI quad support made the DT properties mandatory, breaking
compatibility with existing systems. Fix that by making them optional,
also improving the error messages while we're at it.

Signed-off-by: Mark Brown <broonie@linaro.org>
Tested-by: Stephen Warren <swarren@nvidia.com>

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index f0a6582061d521950c22df6df9b578b26a625530..7557f611457ffb0b4d6635218c6bedf23112e39a 100644 (file)
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -871,47 +871,43 @@ static void of_register_spi_devices(struct spi_master *master)
 
                /* Device DUAL/QUAD mode */
                prop = of_get_property(nc, "spi-tx-nbits", &len);
-               if (!prop || len < sizeof(*prop)) {
-                       dev_err(&master->dev, "%s has no 'spi-tx-nbits' property\n",
-                               nc->full_name);
-                       spi_dev_put(spi);
-                       continue;
-               }
-               switch (be32_to_cpup(prop)) {
-               case SPI_NBITS_SINGLE:
-                       break;
-               case SPI_NBITS_DUAL:
-                       spi->mode |= SPI_TX_DUAL;
-                       break;
-               case SPI_NBITS_QUAD:
-                       spi->mode |= SPI_TX_QUAD;
-                       break;
-               default:
-                       dev_err(&master->dev, "spi-tx-nbits value is not supported\n");
-                       spi_dev_put(spi);
-                       continue;
+               if (prop && len == sizeof(*prop)) {
+                       switch (be32_to_cpup(prop)) {
+                       case SPI_NBITS_SINGLE:
+                               break;
+                       case SPI_NBITS_DUAL:
+                               spi->mode |= SPI_TX_DUAL;
+                               break;
+                       case SPI_NBITS_QUAD:
+                               spi->mode |= SPI_TX_QUAD;
+                               break;
+                       default:
+                               dev_err(&master->dev,
+                                       "spi-tx-nbits %d not supported\n",
+                                       be32_to_cpup(prop));
+                               spi_dev_put(spi);
+                               continue;
+                       }
                }
 
                prop = of_get_property(nc, "spi-rx-nbits", &len);
-               if (!prop || len < sizeof(*prop)) {
-                       dev_err(&master->dev, "%s has no 'spi-rx-nbits' property\n",
-                               nc->full_name);
-                       spi_dev_put(spi);
-                       continue;
-               }
-               switch (be32_to_cpup(prop)) {
-               case SPI_NBITS_SINGLE:
-                       break;
-               case SPI_NBITS_DUAL:
-                       spi->mode |= SPI_RX_DUAL;
-                       break;
-               case SPI_NBITS_QUAD:
-                       spi->mode |= SPI_RX_QUAD;
-                       break;
-               default:
-                       dev_err(&master->dev, "spi-rx-nbits value is not supported\n");
-                       spi_dev_put(spi);
-                       continue;
+               if (prop && len == sizeof(*prop)) {
+                       switch (be32_to_cpup(prop)) {
+                       case SPI_NBITS_SINGLE:
+                               break;
+                       case SPI_NBITS_DUAL:
+                               spi->mode |= SPI_RX_DUAL;
+                               break;
+                       case SPI_NBITS_QUAD:
+                               spi->mode |= SPI_RX_QUAD;
+                               break;
+                       default:
+                               dev_err(&master->dev,
+                                       "spi-rx-nbits %d not supported\n",
+                                       be32_to_cpup(prop));
+                               spi_dev_put(spi);
+                               continue;
+                       }
                }
 
                /* Device speed */