[PATCH] firmware: xilinx: Fix an error handling path in 'zynqmp_firmware_probe()'

[PATCH] firmware: xilinx: Fix an error handling path in 'zynqmp_firmware_probe()'

[Christophe JAILLET]

If 'mfd_add_devices()' fails, we must undo 'zynqmp_pm_api_debugfs_init()'
otherwise some debugfs directory and files will be left.

Just move the call to 'zynqmp_pm_api_debugfs_init()' a few lines below to
fix the issue.

Fixes: e23d9c6d0d49 ("drivers: soc: xilinx: Add ZynqMP power domain driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
Not related to this fix, but I think that:
   - a call to 'of_platform_depopulate()' is missing in the remove function
   - we shouldn't return of_platform_populate(); directly because we
     don't have the opportunity to call 'mfd_remove_devices()' as done in
     the remove function, and 'of_platform_depopulate()' for what have
     been populated yet

I'm not familiar with this API, so I just point it out to get feedback.
---
 drivers/firmware/xilinx/zynqmp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index 8095fa84d5d7..8d1ff2454e2e 100644
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c
@@ -1235,8 +1235,6 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
 	pr_info("%s Trustzone version v%d.%d\n", __func__,
 		pm_tz_version >> 16, pm_tz_version & 0xFFFF);
 
-	zynqmp_pm_api_debugfs_init();
-
 	ret = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE, firmware_devs,
 			      ARRAY_SIZE(firmware_devs), NULL, 0, NULL);
 	if (ret) {
@@ -1244,6 +1242,8 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
 		return ret;
 	}
 
+	zynqmp_pm_api_debugfs_init();
+
 	return of_platform_populate(dev->of_node, NULL, NULL, dev);
 }
 
-- 
2.25.1

Re: [PATCH] firmware: xilinx: Fix an error handling path in 'zynqmp_firmware_probe()'

[Jolly Shah]

Reviewed-by: Jolly Shah <jolly.shah@xilinx.com>

 > ------Original Message------
 > From: Christophe Jaillet <christophe.jaillet@wanadoo.fr>
 > Sent:  Sunday, May 10, 2020 6:03AM
 > To: Michal Simek <michal.simek@xilinx.com>, Rajan Vaja 
<rajan.vaja@xilinx.com>, Jolly Shah <jolly.shah@xilinx.com>, 'Greg Kh' 
<gregkh@linuxfoundation.org>, Tejas Patel <tejas.patel@xilinx.com>, 
Manish Narani <manish.narani@xilinx.com>, Ravi Patel <ravi.patel@xilinx.com>
 > Cc: Linux-arm-kernel@lists.infradead.org 
<linux-arm-kernel@lists.infradead.org>, Linux-kernel@vger.kernel.org 
<linux-kernel@vger.kernel.org>, Kernel-janitors 
<kernel-janitors@vger.kernel.org>, Christophe Jaillet 
<christophe.jaillet@wanadoo.fr>
 > Subject: [PATCH] firmware: xilinx: Fix an error handling path in 
'zynqmp_firmware_probe()'
 >
> If 'mfd_add_devices()' fails, we must undo 'zynqmp_pm_api_debugfs_init()'
> otherwise some debugfs directory and files will be left.
> 
> Just move the call to 'zynqmp_pm_api_debugfs_init()' a few lines below to
> fix the issue.
> 
> Fixes: e23d9c6d0d49 ("drivers: soc: xilinx: Add ZynqMP power domain driver")
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
> Not related to this fix, but I think that:
>     - a call to 'of_platform_depopulate()' is missing in the remove function
>     - we shouldn't return of_platform_populate(); directly because we
>       don't have the opportunity to call 'mfd_remove_devices()' as done in
>       the remove function, and 'of_platform_depopulate()' for what have
>       been populated yet
> 
> I'm not familiar with this API, so I just point it out to get feedback.

Agree. This needs to be fixed.

Thanks,
Jolly Shah


> ---
>   drivers/firmware/xilinx/zynqmp.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
> index 8095fa84d5d7..8d1ff2454e2e 100644
> --- a/drivers/firmware/xilinx/zynqmp.c
> +++ b/drivers/firmware/xilinx/zynqmp.c
> @@ -1235,8 +1235,6 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
>   	pr_info("%s Trustzone version v%d.%d\n", __func__,
>   		pm_tz_version >> 16, pm_tz_version & 0xFFFF);
>   
> -	zynqmp_pm_api_debugfs_init();
> -
>   	ret = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE, firmware_devs,
>   			      ARRAY_SIZE(firmware_devs), NULL, 0, NULL);
>   	if (ret) {
> @@ -1244,6 +1242,8 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
>   		return ret;
>   	}
>   
> +	zynqmp_pm_api_debugfs_init();
> +
>   	return of_platform_populate(dev->of_node, NULL, NULL, dev);
>   }
>   
>