Re: [PATCH] ASoC: amd: Add error checking to probe function

From: Agrawal, Akshu
Date: Tue Nov 21 2017 - 01:15:43 EST

On 11/21/2017 10:17 AM, Deucher, Alexander wrote:
-----Original Message-----
From: Guenter Roeck [mailto:groeck7@xxxxxxxxx] On Behalf Of Guenter
Sent: Monday, November 20, 2017 11:28 PM
To: Liam Girdwood
Cc: Mark Brown; Jaroslav Kysela; Takashi Iwai; alsa-devel@xxxxxxxxxxxxxxxx;
linux-kernel@xxxxxxxxxxxxxxx; Guenter Roeck; Deucher, Alexander; Dominik
Behr; Daniel Kurtz
Subject: [PATCH] ASoC: amd: Add error checking to probe function

The acp_audio_dma does not perform sufficient error checking in its probe
function. This can result in crashes if a critical error path is

Fixes: 7c31335a03b6a ("ASoC: AMD: add AMD ASoC ACP 2.x DMA driver")
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Cc: Dominik Behr <dbehr@xxxxxxxxxxxx>
Cc: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
I didn't add an error check to acp_init() since I was not sure if
its return value is ignored on purpose.

Vijendar, Akshu can you comment?

This is also the case of missing error check.
acp_init will return error if either sw reset did not happen or clock did not get enabled. In both cases we should error out in probe.

The patch looks good to me.
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>

sound/soc/amd/acp-pcm-dma.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/sound/soc/amd/acp-pcm-dma.c b/sound/soc/amd/acp-pcm-
index 9f521a55d610..b5e41df6bb3a 100644
--- a/sound/soc/amd/acp-pcm-dma.c
+++ b/sound/soc/amd/acp-pcm-dma.c
@@ -1051,6 +1051,11 @@ static int acp_audio_probe(struct platform_device
struct resource *res;
const u32 *pdata = pdev->dev.platform_data;

+ if (!pdata) {
+ dev_err(&pdev->dev, "Missing platform data\n");
+ return -ENODEV;
+ }
audio_drv_data = devm_kzalloc(&pdev->dev, sizeof(struct
if (audio_drv_data == NULL)
@@ -1058,6 +1063,8 @@ static int acp_audio_probe(struct platform_device

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
audio_drv_data->acp_mmio = devm_ioremap_resource(&pdev-
dev, res);
+ if (IS_ERR(audio_drv_data->acp_mmio))
+ return PTR_ERR(audio_drv_data->acp_mmio);

/* The following members gets populated in device 'open'
* function. Till then interrupts are disabled in 'acp_init'