On 2016/8/22 19:08, Andy Shevchenko wrote:

On Fri, 2016-07-15 at 19:01 +0800, Kefeng Wang wrote:

quoted

We can safely use dw8250_set_termios() as the default set_termios
callback instead of serial8250_do_set_termios(), so do it.

So, current set_termios() relies on clock to be defined or be an error
pointer. I'm not sure that it handles NULL properly.

So, the question is does set_termios() handle all possible cases? If no,
do we guarantee that the case it doesn't handle never happened?

Answer to this question and amend either the patch or improve commit
message.

If clk do be NUL, uartclk will be set wrong value, zero, will judge this case
in dw8250_set_termios, then make it as default callback.

quoted

Signed-off-by: Kefeng Wang <redacted>
---
 drivers/tty/serial/8250/8250_dw.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/tty/serial/8250/8250_dw.c

b/drivers/tty/serial/8250/8250_dw.c
index e199696..65f3da7 100644

--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c

@@ -301,7 +301,6 @@ static void dw8250_quirks(struct uart_port *p,

struct dw8250_data *data)
 		p->iotype = UPIO_MEM32;
 		p->regshift = 2;
 		p->serial_in = dw8250_serial_in32;
-		p->set_termios = dw8250_set_termios;
 		/* So far none of there implement the Busy
Functionality */
 		data->uart_16550_compatible = true;
 	}

@@ -309,7 +308,6 @@ static void dw8250_quirks(struct uart_port *p,

struct dw8250_data *data)
 	/* Platforms with iDMA */
 	if (platform_get_resource_byname(to_platform_device(p->dev),
 					 IORESOURCE_MEM,
"lpss_priv")) {
-		p->set_termios = dw8250_set_termios;
 		data->dma.rx_param = p->dev->parent;
 		data->dma.tx_param = p->dev->parent;
 		data->dma.fn = dw8250_idma_filter;

@@ -386,6 +384,7 @@ static int dw8250_probe(struct platform_device

*pdev)
 	p->iotype	= UPIO_MEM;
 	p->serial_in	= dw8250_serial_in;
 	p->serial_out	= dw8250_serial_out;
+	p->set_termios	= dw8250_set_termios;
 
 	p->membase = devm_ioremap(&pdev->dev, regs->start,
resource_size(regs));
 	if (!p->membase)