spi: move more spi_setup() functionality into core

Move some common spi_setup() error checks into the SPI framework from the
spi_master controller drivers:

 - Add a new "mode_bits" field to spi_master

 - Use that in spi_setup to validate the spi->mode value being
   requested.  Setting this new field is now mandatory for any
   controller supporting more than vanilla SPI_MODE_0.

 - Update all spi_master drivers to:

     * Initialize that field
     * Remove current spi_setup() checks using that value.

This is a net minor code shrink.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 9 deletions

diff --git a/drivers/spi/spi_imx.c b/drivers/spi/spi_imx.c
index 26d5ef0..c195e45 100644
--- a/drivers/spi/spi_imx.c
+++ b/drivers/spi/spi_imx.c
@@ -1171,9 +1171,6 @@ msg_rejected:
 	return -EINVAL;
 }
 
-/* the spi->mode bits understood by this driver: */
-#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
-
 /* On first setup bad values must free chip_data memory since will cause
    spi_new_device to fail. Bad value setup from protocol driver are simply not
    applied and notified to the calling driver. */
@@ -1186,12 +1183,6 @@ static int setup(struct spi_device *spi)
 	u32 tmp;
 	int status = 0;
 
-	if (spi->mode & ~MODEBITS) {
-		dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
-			spi->mode & ~MODEBITS);
-		return -EINVAL;
-	}
-
 	/* Get controller data */
 	chip_info = spi->controller_data;
 
@@ -1478,6 +1469,9 @@ static int __init spi_imx_probe(struct platform_device *pdev)
 	drv_data->master_info = platform_info;
 	drv_data->pdev = pdev;
 
+	/* the spi->mode bits understood by this driver: */
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
+
 	master->bus_num = pdev->id;
 	master->num_chipselect = platform_info->num_chipselect;
 	master->dma_alignment = DMA_ALIGNMENT;