spi_bitbang: always grab lock with irqs blocked
Fix a glitch reported by lockdep in the spi_bitbang code: it needs to
consistently block IRQs when holding that spinlock.
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>
diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c
index 81639c6..f7f8580 100644
--- a/drivers/spi/spi_bitbang.c
+++ b/drivers/spi/spi_bitbang.c
@@ -184,6 +184,7 @@
struct spi_bitbang_cs *cs = spi->controller_state;
struct spi_bitbang *bitbang;
int retval;
+ unsigned long flags;
bitbang = spi_master_get_devdata(spi->master);
@@ -222,12 +223,12 @@
*/
/* deselect chip (low or high) */
- spin_lock(&bitbang->lock);
+ spin_lock_irqsave(&bitbang->lock, flags);
if (!bitbang->busy) {
bitbang->chipselect(spi, BITBANG_CS_INACTIVE);
ndelay(cs->nsecs);
}
- spin_unlock(&bitbang->lock);
+ spin_unlock_irqrestore(&bitbang->lock, flags);
return 0;
}