2 files changed, 14 insertions, 4 deletions

diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt b/Documentation/devicetree/bindings/spi/spi-bus.txt
index 296015e3c632..800dafe5b01b 100644
--- a/Documentation/devicetree/bindings/spi/spi-bus.txt
+++ b/Documentation/devicetree/bindings/spi/spi-bus.txt
@@ -55,6 +55,16 @@ contain the following properties.
                 chip select active high
 - spi-3wire       - (optional) Empty property indicating device requires
                     3-wire mode.
+- spi-tx-bus-width - (optional) The bus width(number of data wires) that
+                      used for MOSI. Defaults to 1 if not present.
+- spi-rx-bus-width - (optional) The bus width(number of data wires) that
+                      used for MISO. Defaults to 1 if not present.
+
+Some SPI controllers and devices support Dual and Quad SPI transfer mode.
+It allows data in SPI system transfered in 2 wires(DUAL) or 4 wires(QUAD).
+Now the value that spi-tx-bus-width and spi-rx-bus-width can receive is
+only 1(SINGLE), 2(DUAL) and 4(QUAD).
+Dual/Quad mode is not allowed when 3-wire mode is used.
 
 If a gpio chipselect is used for the SPI slave the gpio number will be passed
 via the cs_gpio
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 7557f611457f..0075318f4fa1 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -870,7 +870,7 @@ static void of_register_spi_devices(struct spi_master *master)
                         spi->mode |= SPI_3WIRE;
 
                 /* Device DUAL/QUAD mode */
-                prop = of_get_property(nc, "spi-tx-nbits", &len);
+                prop = of_get_property(nc, "spi-tx-bus-width", &len);
                 if (prop && len == sizeof(*prop)) {
                         switch (be32_to_cpup(prop)) {
                         case SPI_NBITS_SINGLE:
@@ -883,14 +883,14 @@ static void of_register_spi_devices(struct spi_master *master)
                                 break;
                         default:
                                 dev_err(&master->dev,
-                                        "spi-tx-nbits %d not supported\n",
+                                        "spi-tx-bus-width %d not supported\n",
                                         be32_to_cpup(prop));
                                 spi_dev_put(spi);
                                 continue;
                         }
                 }
 
-                prop = of_get_property(nc, "spi-rx-nbits", &len);
+                prop = of_get_property(nc, "spi-rx-bus-width", &len);
                 if (prop && len == sizeof(*prop)) {
                         switch (be32_to_cpup(prop)) {
                         case SPI_NBITS_SINGLE:
@@ -903,7 +903,7 @@ static void of_register_spi_devices(struct spi_master *master)
                                 break;
                         default:
                                 dev_err(&master->dev,
-                                        "spi-rx-nbits %d not supported\n",
+                                        "spi-rx-bus-width %d not supported\n",
                                         be32_to_cpup(prop));
                                 spi_dev_put(spi);
                                 continue;