diff mbox series

[v2,1/1] serial: 8520_mtk: Prepare for platform_get_irq_optional() changes

Message ID 20211217181547.48182-1-andriy.shevchenko@linux.intel.com
State New
Headers show
Series [v2,1/1] serial: 8520_mtk: Prepare for platform_get_irq_optional() changes | expand

Commit Message

Andy Shevchenko Dec. 17, 2021, 6:15 p.m. UTC 
The platform_get_irq_optional() is going to be changed in a way
that the result of it:
   = 0 means no IRQ is provided
   < 0 means the error which needs to be propagated to the upper layers
   > 0 valid vIRQ is allocated

In this case, drop check for 0. Note, the 0 is not valid vIRQ and
platform_get_irq_optional() issues a big WARN() in such case,

It's safe to assume that 0 is not valid IRQ in this case since
the driver is only instantiated via Device Tree and corresponding
OF APIs should never ever return 0 for valid IRQ. Otherwise it is
a regression there.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v2: explained why it's safe to assume 0 is not valid here (Greg)
 drivers/tty/serial/8250/8250_mtk.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Greg Kroah-Hartman March 4, 2022, 6:48 p.m. UTC | #1 
On Fri, Mar 04, 2022 at 08:11:10PM +0200, Andy Shevchenko wrote:
> On Fri, Dec 17, 2021 at 08:15:47PM +0200, Andy Shevchenko wrote:
> > The platform_get_irq_optional() is going to be changed in a way
> > that the result of it:
> >    = 0 means no IRQ is provided
> >    < 0 means the error which needs to be propagated to the upper layers
> >    > 0 valid vIRQ is allocated
> > 
> > In this case, drop check for 0. Note, the 0 is not valid vIRQ and
> > platform_get_irq_optional() issues a big WARN() in such case,
> > 
> > It's safe to assume that 0 is not valid IRQ in this case since
> > the driver is only instantiated via Device Tree and corresponding
> > OF APIs should never ever return 0 for valid IRQ. Otherwise it is
> > a regression there.
> 
> Can it be applied now?

What changed to make this viable?
diff mbox series

Patch

diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index fb65dc601b23..328ab074fd89 100644
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c
@@ -621,7 +621,7 @@  static int __maybe_unused mtk8250_suspend(struct device *dev)
 	serial8250_suspend_port(data->line);
 
 	pinctrl_pm_select_sleep_state(dev);
-	if (irq >= 0) {
+	if (irq > 0) {
 		err = enable_irq_wake(irq);
 		if (err) {
 			dev_err(dev,
@@ -641,7 +641,7 @@  static int __maybe_unused mtk8250_resume(struct device *dev)
 	struct mtk8250_data *data = dev_get_drvdata(dev);
 	int irq = data->rx_wakeup_irq;
 
-	if (irq >= 0)
+	if (irq > 0)
 		disable_irq_wake(irq);
 	pinctrl_pm_select_default_state(dev);