Re: [igt-dev] [PATCH i-g-t] tests/device_reset: fix logic to unbind when snd_hda_intel is loaded

[Nirmoy Das <nirmoy.das@linux.intel.com>]

On 10/19/2023 11:15 AM, Mauro Carvalho Chehab wrote:
> From: Mauro Carvalho Chehab <mchehab@kernel.org>
>
> For i915 devices are used, there's a glue with snd_hda_intel.
> Currently, such glue requires that the audio driver to be unused
> and removed before being able to remove the i915 driver.
>
> There is already a logic at igt library to do it the right way,
> but device_reset currently doesn't use.
>
> Also, the logic is hardcoded to work only with Haswell, Broadwell
> and DG1.
>
> Change the logic to use the proper logic to remove such
> module using the library.
>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

Looks much cleaner.

Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>


> ---
>   tests/device_reset.c | 47 ++++++--------------------------------------
>   1 file changed, 6 insertions(+), 41 deletions(-)
>
> diff --git a/tests/device_reset.c b/tests/device_reset.c
> index 9ebd479dfefa..ef08164aad41 100644
> --- a/tests/device_reset.c
> +++ b/tests/device_reset.c
> @@ -65,7 +65,7 @@ struct device_fds {
>   		int slot_dir; /* pci hotplug slots fd */
>   	} fds;
>   	char dev_bus_addr[DEV_BUS_ADDR_LEN];
> -	bool snd_unload;
> +	char *snd_driver;
>   };
>   
>   static int __open_sysfs_dir(int fd, const char* path)
> @@ -188,7 +188,6 @@ static void init_device_fds(struct device_fds *dev)
>   {
>   	char dev_path[PATH_MAX];
>   	char *addr_pos;
> -	uint32_t devid;
>   
>   	igt_debug("open device\n");
>   	/**
> @@ -198,18 +197,9 @@ static void init_device_fds(struct device_fds *dev)
>   	 */
>   	dev->fds.dev = __drm_open_driver(DRIVER_ANY);
>   	igt_assert_fd(dev->fds.dev);
> -	if (is_i915_device(dev->fds.dev)) {
> +	if (is_i915_device(dev->fds.dev))
>   		igt_require_gem(dev->fds.dev);
>   
> -		devid = intel_get_drm_devid(dev->fds.dev);
> -		if ((IS_HASWELL(devid) || IS_BROADWELL(devid) ||
> -		     IS_DG1(devid)) &&
> -		     (igt_kmod_is_loaded("snd_hda_intel"))) {
> -			igt_debug("Enable WA to unload snd driver\n");
> -			dev->snd_unload = true;
> -		}
> -	}
> -
>   	igt_assert(device_sysfs_path(dev->fds.dev, dev_path));
>   	addr_pos = strrchr(dev_path, '/');
>   	igt_assert(addr_pos);
> @@ -312,33 +302,8 @@ static bool is_sysfs_cold_reset_supported(int slot_fd)
>   /* Unbind the driver from the device */
>   static void driver_unbind(struct device_fds *dev)
>   {
> -	/**
> -	 * FIXME: Unbinding the i915 driver on affected platforms with
> -	 * audio results in a kernel WARN on "i915 raw-wakerefs=1
> -	 * wakelocks=1 on cleanup". The below CI friendly user level
> -	 * workaround to unload and de-couple audio from IGT testing,
> -	 * prevents the warning from appearing. Drop this hack as soon
> -	 * as this is fixed in the kernel. unbind/re-bind validation
> -	 * on audio side is not robust and we could have potential
> -	 * failures blocking display CI, currently this seems to the
> -	 * safest and easiest way out.
> -	 */
> -	if (dev->snd_unload) {
> -		igt_terminate_process(SIGTERM, "alsactl");
> -
> -		/* unbind snd_hda_intel */
> -		kick_snd_hda_intel();
> -
> -		if (igt_kmod_unload("snd_hda_intel", 0)) {
> -			dev->snd_unload = false;
> -			igt_warn("Could not unload snd_hda_intel\n");
> -			igt_kmod_list_loaded();
> -			igt_lsof("/dev/snd");
> -			igt_skip("Audio is in use, skipping\n");
> -		} else {
> -			igt_info("Preventively unloaded snd_hda_intel\n");
> -		}
> -	}
> +	if (is_i915_device(dev->fds.dev))
> +		igt_audio_driver_unload(&dev->snd_driver);
>   
>   	igt_debug("unbind the driver from the device\n");
>   	igt_assert(igt_sysfs_set(dev->fds.drv_dir, "unbind",
> @@ -352,8 +317,8 @@ static void driver_bind(struct device_fds *dev)
>   	igt_abort_on_f(!igt_sysfs_set(dev->fds.drv_dir, "bind",
>   		       dev->dev_bus_addr), "driver rebind failed");
>   
> -	if (dev->snd_unload)
> -		igt_kmod_load("snd_hda_intel", NULL);
> +	if (dev->snd_driver)
> +		igt_kmod_load(dev->snd_driver, NULL);
>   }
>   
>   /* Initiate device reset */