Re: [PATCH v4 3/4] media: raspberrypi: Add support for RP1-CFE

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

On Thu, Sep 05, 2024 at 06:50:48PM +0800, kernel test robot wrote:
> Hi Tomi,
> 
> kernel test robot noticed the following build warnings:
> 
> [auto build test WARNING on 431c1646e1f86b949fa3685efc50b660a364c2b6]
> 
> url:    https://github.com/intel-lab-lkp/linux/commits/Tomi-Valkeinen/media-uapi-Add-meta-formats-for-PiSP-FE-config-and-stats/20240904-192729
> base:   431c1646e1f86b949fa3685efc50b660a364c2b6
> patch link:    https://lore.kernel.org/r/20240904-rp1-cfe-v4-3-f1b5b3d69c81%40ideasonboard.com
> patch subject: [PATCH v4 3/4] media: raspberrypi: Add support for RP1-CFE
> config: m68k-allmodconfig (https://download.01.org/0day-ci/archive/20240905/202409051822.ZzUGw3XQ-lkp@intel.com/config)
> compiler: m68k-linux-gcc (GCC) 14.1.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240905/202409051822.ZzUGw3XQ-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202409051822.ZzUGw3XQ-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
> >> drivers/media/platform/raspberrypi/rp1-cfe/cfe.c:2445:12: warning: 'cfe_runtime_resume' defined but not used [-Wunused-function]
>     2445 | static int cfe_runtime_resume(struct device *dev)
>          |            ^~~~~~~~~~~~~~~~~~
> >> drivers/media/platform/raspberrypi/rp1-cfe/cfe.c:2435:12: warning: 'cfe_runtime_suspend' defined but not used [-Wunused-function]
>     2435 | static int cfe_runtime_suspend(struct device *dev)
>          |            ^~~~~~~~~~~~~~~~~~~
> vim +/cfe_runtime_resume +2445 drivers/media/platform/raspberrypi/rp1-cfe/cfe.c

The recommended way to fix this is to switch from SET_RUNTIME_PM_OPS()
to RUNTIME_PM_OPS() and use pm_ptr() to set .driver.pm. This being said,
the driver won't work on a kernel with !CONFIG_PM given how you
implemented probe() and remove().

The pisp-be driver suffered from the same issue and Jacopo fixed it in
the last version. You can have a look at implement something similar.

>   2434	
> > 2435	static int cfe_runtime_suspend(struct device *dev)
>   2436	{
>   2437		struct platform_device *pdev = to_platform_device(dev);
>   2438		struct cfe_device *cfe = platform_get_drvdata(pdev);
>   2439	
>   2440		clk_disable_unprepare(cfe->clk);
>   2441	
>   2442		return 0;
>   2443	}
>   2444	
> > 2445	static int cfe_runtime_resume(struct device *dev)
>   2446	{
>   2447		struct platform_device *pdev = to_platform_device(dev);
>   2448		struct cfe_device *cfe = platform_get_drvdata(pdev);
>   2449		int ret;
>   2450	
>   2451		ret = clk_prepare_enable(cfe->clk);
>   2452		if (ret) {
>   2453			dev_err(dev, "Unable to enable clock\n");
>   2454			return ret;
>   2455		}
>   2456	
>   2457		return 0;
>   2458	}
>   2459	

-- 
Regards,

Laurent Pinchart