Re: [PATCH 1/2] serial: mctrl_gpio: Check if GPIO property exisits before requesting it

[Greg Kroah-Hartman]

On Wed, May 22, 2019 at 02:11:16PM +0200, Stefan Roese wrote:
> This patch adds a check for the GPIOs property existence, before the
> GPIO is requested. This fixes an issue seen when the 8250 mctrl_gpio
> support is added (2nd patch in this patch series) on x86 platforms using
> ACPI. Please find a details problem description here:
> 
> https://lkml.org/lkml/2016/8/9/357

Can you change this to a lore.kernel.org link instead?

Actually, just put the information in here, no one should ever have to
search somewhere else to determine what happened in a changelog entry.

thanks,

greg k-h

[PATCH 1/2] serial: mctrl_gpio: Check if GPIO property exisits before requesting it

[Stefan Roese]

This patch adds a check for the GPIOs property existence, before the
GPIO is requested. This fixes an issue seen when the 8250 mctrl_gpio
support is added (2nd patch in this patch series) on x86 platforms using
ACPI. Please find a details problem description here:

https://lkml.org/lkml/2016/8/9/357

Signed-off-by: Stefan Roese 
Cc: Mika Westerberg 
Cc: Andy Shevchenko 
Cc: Yegor Yefremov 
Cc: Greg Kroah-Hartman 
Cc: Giulio Benetti 
---
 drivers/tty/serial/serial_mctrl_gpio.c | 7 +++
 1 file changed, 7 insertions(+)

diff --git a/drivers/tty/serial/serial_mctrl_gpio.c 
b/drivers/tty/serial/serial_mctrl_gpio.c
index 39ed56214cd3..cac50b20a119 100644
--- a/drivers/tty/serial/serial_mctrl_gpio.c
+++ b/drivers/tty/serial/serial_mctrl_gpio.c
@@ -116,6 +116,13 @@ struct mctrl_gpios *mctrl_gpio_init_noauto(struct device 
*dev, unsigned int idx)
 
for (i = 0; i < UART_GPIO_MAX; i++) {
enum gpiod_flags flags;
+   char *gpio_str;
+
+   /* Check if GPIO property exists and continue if not */
+   gpio_str = kasprintf(GFP_KERNEL, "%s-gpios",
+mctrl_gpios_desc[i].name);
+   if (!device_property_present(dev, gpio_str))
+   continue;
 
if (mctrl_gpios_desc[i].dir_out)
flags = GPIOD_OUT_LOW;
-- 
2.21.0