From: Sascha Hauer <s.ha...@pengutronix.de>

Use read-modify-write instead of a simple write to change the register
contents, to close existing the race window between the original manual
read and write.

Signed-off-by: Sascha Hauer <s.ha...@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <m...@pengutronix.de>
---
 drivers/net/can/mcp251x.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/drivers/net/can/mcp251x.c b/drivers/net/can/mcp251x.c
index 9b3466a..7e2f951 100644
--- a/drivers/net/can/mcp251x.c
+++ b/drivers/net/can/mcp251x.c
@@ -785,7 +785,8 @@ static irqreturn_t mcp251x_can_ist(int irq, void *dev_id)
 
                mcp251x_write_bits(spi, CANINTF, intf, 0x00);
 
-               mcp251x_write_reg(spi, EFLG, 0x00);
+               if (eflag)
+                       mcp251x_write_bits(spi, EFLG, eflag, 0x00);
 
                /* Update can state */
                if (eflag & EFLG_TXBO) {
-- 
1.7.0.4

_______________________________________________
Socketcan-core mailing list
Socketcan-core@lists.berlios.de
https://lists.berlios.de/mailman/listinfo/socketcan-core

Reply via email to