spi/bitbang: check for setup_transfer during initialization

setup_transfer is mandatory if spi_bitbang_transfer is used, so
check for it during initialization and not each time during runtime.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 4 insertions, 9 deletions

diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c
index 8b55724d5f39..14a63f6010d1 100644
--- a/drivers/spi/spi_bitbang.c
+++ b/drivers/spi/spi_bitbang.c
@@ -259,10 +259,6 @@ static void bitbang_work(struct work_struct *work)
         struct spi_bitbang      *bitbang =
                 container_of(work, struct spi_bitbang, work);
         unsigned long           flags;
-        int                     (*setup_transfer)(struct spi_device *,
-                                        struct spi_transfer *);
-
-        setup_transfer = bitbang->setup_transfer;
 
         spin_lock_irqsave(&bitbang->lock, flags);
         bitbang->busy = 1;
@@ -300,11 +296,7 @@ static void bitbang_work(struct work_struct *work)
 
                         /* init (-1) or override (1) transfer params */
                         if (do_setup != 0) {
-                                if (!setup_transfer) {
-                                        status = -ENOPROTOOPT;
-                                        break;
-                                }
-                                status = setup_transfer(spi, t);
+                                status = bitbang->setup_transfer(spi, t);
                                 if (status < 0)
                                         break;
                                 if (do_setup == -1)
@@ -465,6 +457,9 @@ int spi_bitbang_start(struct spi_bitbang *bitbang)
                 }
         } else if (!bitbang->master->setup)
                 return -EINVAL;
+        if (bitbang->master->transfer == spi_bitbang_transfer &&
+                        !bitbang->setup_transfer)
+                return -EINVAL;
 
         /* this task is the only thing to touch the SPI bits */
         bitbang->busy = 0;