Re: [PATCH] drivers: thermal: processor_thermal: mark pm function __maybe_unused

[Zhang Rui <rui.zhang@intel.com>]

Hi, Arnd,

thanks for the report.

On 一, 2019-07-08 at 14:47 +0200, Arnd Bergmann wrote:
> Without CONFIG_PM, we get a harmless warning:
> 
> drivers/thermal/intel/int340x_thermal/processor_thermal_device.c:446:
> 12: error: 'proc_thermal_resume' defined but not used [-
> Werror=unused-function]
>  static int proc_thermal_resume(struct device *dev)
> 
> Mark it __maybe_unused to shut up the warning.
> 
> Fixes: aaba9791fbb4 ("drivers: thermal: processor_thermal: Read PPCC
> on resume")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  .../thermal/intel/int340x_thermal/processor_thermal_device.c    | 2
> +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git
> a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> index a3210f09f366..5ce639a99330 100644
> ---
> a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> +++
> b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
> @@ -443,7 +443,7 @@ static void  proc_thermal_pci_remove(struct
> pci_dev *pdev)
>  	pci_disable_device(pdev);
>  }
>  
> -static int proc_thermal_resume(struct device *dev)
> +static int __maybe_unused proc_thermal_resume(struct device *dev)
>  {
>  	struct proc_thermal_device *proc_dev;
>  
I'd rather prefer to add #ifdef CONFIG_PM_SLEEP for
proc_thermal_resume().
Just like the patch below, what do you think?

thanks,
rui

From 6c395f66e98c895cf3ebf87c0b2fc63b6a57a196 Mon Sep 17 00:00:00 2001
From: Zhang Rui <rui.zhang@intel.com>
Date: Tue, 9 Jul 2019 21:19:12 +0800
Subject: [PATCH] drivers: thermal: processor_thermal_device: Fix build warning

As a system sleep callback, proc_thermal_resume() should be defined only
if CONFIG_PM_SLEEP is set.

This fixes a build warning when CONFIG_PM_SLEEP is not set,
drivers/thermal/intel/int340x_thermal/processor_thermal_device.c:446:12: error: 'proc_thermal_resume' defined but not used [-Werror=unused-function]
 static int proc_thermal_resume(struct device *dev)

Fixes: aaba9791fbb4 ("drivers: thermal: processor_thermal: Read PPCC on resume")
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
---
 drivers/thermal/intel/int340x_thermal/processor_thermal_device.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
index a3210f0..77dae1e 100644
--- a/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
+++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
@@ -443,6 +443,7 @@ static void  proc_thermal_pci_remove(struct pci_dev *pdev)
 	pci_disable_device(pdev);
 }
 
+#ifdef CONFIG_PM_SLEEP
 static int proc_thermal_resume(struct device *dev)
 {
 	struct proc_thermal_device *proc_dev;
@@ -452,6 +453,9 @@ static int proc_thermal_resume(struct device *dev)
 
 	return 0;
 }
+#else
+#define proc_thermal_resume NULL
+#endif
 
 static SIMPLE_DEV_PM_OPS(proc_thermal_pm, NULL, proc_thermal_resume);
 
-- 
2.7.4