spi: convert drivers to use bits_per_word_mask

Fill in the recently added spi_master.bits_per_word_mask field in as
many drivers as possible. Make related cleanups, such as removing any
redundant error-checking, or empty setup callbacks.

Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index 0021fc4..a7801a8 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -239,9 +239,6 @@
 	struct spi_gpio		*spi_gpio = spi_to_spi_gpio(spi);
 	struct device_node	*np = spi->master->dev.of_node;
 
-	if (spi->bits_per_word > 32)
-		return -EINVAL;
-
 	if (np) {
 		/*
 		 * In DT environments, the CS GPIOs have already been
@@ -446,6 +443,7 @@
 	if (pdata)
 		spi_gpio->pdata = *pdata;
 
+	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
 	master->flags = master_flags;
 	master->bus_num = pdev->id;
 	master->num_chipselect = SPI_N_CHIPSEL;