[PATCH v3] serial: 8250_dw: fix wrong logic in dw8250_check_lcr()

From: Kefeng Wang
Date: Mon Apr 04 2016 - 23:30:28 EST


Commit cdcea058e510 ("serial: 8250_dw: Avoid serial_outx code duplicate
with new dw8250_check_lcr()") introduce a wrong logic when write val to
LCR reg. When CONFIG_64BIT enabled, __raw_writeq is used unconditionally.

The __raw_readq/__raw_writeq is introduced by commit bca2092d7897 ("serial:
8250_dw: Use 64-bit access for OCTEON.") for OCTEON, so for !PORT_OCTEON,
we better to use coincident write func.

Fixes: cdcea058e510("serial: 8250_dw: Avoid serial_outx code duplicate with new dw8250_check_lcr()")
Signed-off-by: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx>
---
Keep #ifdef CONFIG_64BIT to ensure it built under arch lacking readq/writeq.

drivers/tty/serial/8250/8250_dw.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index a3fb95d..47d1f3e 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -104,15 +104,16 @@ static void dw8250_check_lcr(struct uart_port *p, int value)
dw8250_force_idle(p);

#ifdef CONFIG_64BIT
- __raw_writeq(value & 0xff, offset);
-#else
+ if (p->type == PORT_OCTEON)
+ __raw_writeq(value & 0xff, offset);
+ else
+#endif
if (p->iotype == UPIO_MEM32)
writel(value, offset);
else if (p->iotype == UPIO_MEM32BE)
iowrite32be(value, offset);
else
writeb(value, offset);
-#endif
}
/*
* FIXME: this deadlocks if port->lock is already held
--
2.6.0.GIT