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, 6 deletions

diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index d54058a903be..73e24ef5a2f9 100644
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -1010,12 +1010,6 @@ static int bfin_spi_setup(struct spi_device *spi)
 	struct driver_data *drv_data = spi_master_get_devdata(spi->master);
 	int ret;
 
-	/* Abort device setup if requested features are not supported */
-	if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST)) {
-		dev_err(&spi->dev, "requested mode not fully supported\n");
-		return -EINVAL;
-	}
-
 	if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
 		return -EINVAL;
 
@@ -1283,6 +1277,9 @@ static int __init bfin_spi_probe(struct platform_device *pdev)
 	drv_data->pdev = pdev;
 	drv_data->pin_req = platform_info->pin_req;
 
+	/* the spi->mode bits supported by this driver: */
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+
 	master->bus_num = pdev->id;
 	master->num_chipselect = platform_info->num_chipselect;
 	master->cleanup = bfin_spi_cleanup;