Re: [PATCH] soc: imx: fix error check in imx8mp_blk_ctrl_probe()

Russell King (Oracle)
2022-09-13T07:39:59Z

On Tue, Sep 13, 2022 at 03:34:34PM +0800, Tang Bin wrote:
> In the function imx8mp_blk_ctrl_probe(),
> dev_pm_domain_attach_by_name() may return NULL in some cases,
> so IS_ERR() doesn't meet the requirements. Thus fix it.
>
> Fixes: 556f5cf9568a ("soc: imx: add i.MX8MP HSIO blk-ctrl")
> Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
> ---
> drivers/soc/imx/imx8mp-blk-ctrl.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/soc/imx/imx8mp-blk-ctrl.c b/drivers/soc/imx/imx8mp-blk-ctrl.c
> index ccb30c6cd..ed8557eaf 100644
> --- a/drivers/soc/imx/imx8mp-blk-ctrl.c
> +++ b/drivers/soc/imx/imx8mp-blk-ctrl.c
> @@ -597,11 +597,11 @@ static int imx8mp_blk_ctrl_probe(struct platform_device *pdev)
>
> domain->power_dev =
> dev_pm_domain_attach_by_name(dev, data->gpc_name);
> - if (IS_ERR(domain->power_dev)) {
> + if (IS_ERR_OR_NULL(domain->power_dev)) {
> dev_err_probe(dev, PTR_ERR(domain->power_dev),
> "failed to attach power domain %s\n",
> data->gpc_name);
> - ret = PTR_ERR(domain->power_dev);
> + ret = PTR_ERR(domain->power_dev) ? : -ENODATA;
> goto cleanup_pds;
> }
> dev_set_name(domain->power_dev, "%s", data->name);

Checking for NULL in this case is likely a good idea, as if
domain->power_dev is NULL, then dev_set_name() will probably oops the
kernel. Whether returning -ENODATA and causing a failure, or whether
moving on to the next domain is a question that the maintainers of
this code need to answer, bearing in mind that NULL here means that
the device doesn't need a power domain.

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