[PATCH v2] ASoC: mediatek: common: handle NULL case in suspend/resume function
When memory allocation for afe->reg_back_up fails, reg_back_up can't be used. Keep the suspend/resume flow but skip register backup when afe->reg_back_up is NULL, in case illegal memory access happens.
Fixes: 283b612429a2 ("ASoC: mediatek: implement mediatek common structure") Signed-off-by: Trevor Wu trevor.wu@mediatek.com Reported-by: Dan Carpenter dan.carpenter@oracle.com --- Change since v1: add Reported-by tag --- sound/soc/mediatek/common/mtk-afe-fe-dai.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/sound/soc/mediatek/common/mtk-afe-fe-dai.c b/sound/soc/mediatek/common/mtk-afe-fe-dai.c index baaa5881b1d4..e95c7c018e7d 100644 --- a/sound/soc/mediatek/common/mtk-afe-fe-dai.c +++ b/sound/soc/mediatek/common/mtk-afe-fe-dai.c @@ -334,9 +334,11 @@ int mtk_afe_suspend(struct snd_soc_component *component) devm_kcalloc(dev, afe->reg_back_up_list_num, sizeof(unsigned int), GFP_KERNEL);
- for (i = 0; i < afe->reg_back_up_list_num; i++) - regmap_read(regmap, afe->reg_back_up_list[i], - &afe->reg_back_up[i]); + if (afe->reg_back_up) { + for (i = 0; i < afe->reg_back_up_list_num; i++) + regmap_read(regmap, afe->reg_back_up_list[i], + &afe->reg_back_up[i]); + }
afe->suspended = true; afe->runtime_suspend(dev); @@ -356,12 +358,13 @@ int mtk_afe_resume(struct snd_soc_component *component)
afe->runtime_resume(dev);
- if (!afe->reg_back_up) + if (!afe->reg_back_up) { dev_dbg(dev, "%s no reg_backup\n", __func__); - - for (i = 0; i < afe->reg_back_up_list_num; i++) - mtk_regmap_write(regmap, afe->reg_back_up_list[i], - afe->reg_back_up[i]); + } else { + for (i = 0; i < afe->reg_back_up_list_num; i++) + mtk_regmap_write(regmap, afe->reg_back_up_list[i], + afe->reg_back_up[i]); + }
afe->suspended = false; return 0;
On Fri, Sep 10, 2021 at 05:26:13PM +0800, Trevor Wu wrote:
When memory allocation for afe->reg_back_up fails, reg_back_up can't be used. Keep the suspend/resume flow but skip register backup when afe->reg_back_up is NULL, in case illegal memory access happens.
It seems like it'd be better to just allocate the buffer at probe time and fail in case we can't get it, I'd be surprised if there's many platforms using this hardware that don't also end up suspending and resuming.
On Fri, 2021-09-10 at 11:23 +0100, Mark Brown wrote:
On Fri, Sep 10, 2021 at 05:26:13PM +0800, Trevor Wu wrote:
When memory allocation for afe->reg_back_up fails, reg_back_up can't be used. Keep the suspend/resume flow but skip register backup when afe->reg_back_up is NULL, in case illegal memory access happens.
It seems like it'd be better to just allocate the buffer at probe time and fail in case we can't get it, I'd be surprised if there's many platforms using this hardware that don't also end up suspending and resuming.
Hi Mark,
Thanks for your suggestion. I agree it's better to allocate the memory at probe time. I think we can still keep the implementation in the suspend/resume function as a fallback solution if user doesn't allocate the memory in probe function.
In the new mediatek SOCs, regcache has been used to handle register backup. Do I need to add the buffer allocation on probe function to the platform in which mtk_afe_suspend and mtk_afe_resume are used?
Thanks, Trevor
On Mon, Sep 13, 2021 at 01:55:38PM +0800, Trevor Wu wrote:
On Fri, 2021-09-10 at 11:23 +0100, Mark Brown wrote:
It seems like it'd be better to just allocate the buffer at probe time and fail in case we can't get it, I'd be surprised if there's many platforms using this hardware that don't also end up suspending and resuming.
Thanks for your suggestion. I agree it's better to allocate the memory at probe time. I think we can still keep the implementation in the suspend/resume function as a fallback solution if user doesn't allocate the memory in probe function.
If you can't allocate it at probe time you should probably just fail the probe.
In the new mediatek SOCs, regcache has been used to handle register backup. Do I need to add the buffer allocation on probe function to the platform in which mtk_afe_suspend and mtk_afe_resume are used?
I think you should have separate implementations if you have both regmap and non-regmap versions of this.
On Fri, 10 Sep 2021 17:26:13 +0800, Trevor Wu wrote:
When memory allocation for afe->reg_back_up fails, reg_back_up can't be used. Keep the suspend/resume flow but skip register backup when afe->reg_back_up is NULL, in case illegal memory access happens.
Applied to
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next
Thanks!
[1/1] ASoC: mediatek: common: handle NULL case in suspend/resume function commit: 1dd038522615b70f5f8945c5631e9e2fa5bd58b1
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Thanks, Mark
participants (2)
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Mark Brown -
Trevor Wu