linux-kernel - Re: [PATCH v3 3/4] mmc: sdhci-xenon: use clk only with DT

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 4 Dec 2020 14:51:01 +0100
From:   Ulf Hansson <ulf.hansson@...aro.org>
To:     Marcin Wojtas <mw@...ihalf.com>
Cc:     Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        "linux-mmc@...r.kernel.org" <linux-mmc@...r.kernel.org>,
        Ziji Hu <huziji@...vell.com>,
        Adrian Hunter <adrian.hunter@...el.com>, jaz@...ihalf.com,
        tn@...ihalf.com, ard.biesheuvel@....com,
        Kostya Porotchkin <kostap@...vell.com>
Subject: Re: [PATCH v3 3/4] mmc: sdhci-xenon: use clk only with DT

On Wed, 2 Dec 2020 at 19:51, Marcin Wojtas <mw@...ihalf.com> wrote:
>
> As a preparation for supporting ACPI, modify the driver
> to use the clk framework only when booting with DT -
> otherwise rely on the configuration done by firmware.
> For that purpose introduce also a custom SDHCI get_max_clock
> callback.
>
> Signed-off-by: Marcin Wojtas <mw@...ihalf.com>
> Acked-by: Adrian Hunter <adrian.hunter@...el.com>
> ---
>  drivers/mmc/host/sdhci-xenon.c | 61 ++++++++++++--------
>  1 file changed, 38 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-xenon.c b/drivers/mmc/host/sdhci-xenon.c

[...]

> @@ -637,10 +650,12 @@ static int xenon_runtime_resume(struct device *dev)
>         struct xenon_priv *priv = sdhci_pltfm_priv(pltfm_host);
>         int ret;
>
> -       ret = clk_prepare_enable(pltfm_host->clk);
> -       if (ret) {
> -               dev_err(dev, "can't enable mainck\n");
> -               return ret;
> +       if (dev->of_node) {

I didn't notice this in the earlier version, my apologies, but there
is no need for this check.

clk_prepare_enable() should cope fine with a NULL argument - and you
only reach this path, if the clock was successfully fetched during the
probe or that it was left to stay NULL for non-DT case.

> +               ret = clk_prepare_enable(pltfm_host->clk);
> +               if (ret) {
> +                       dev_err(dev, "can't enable mainck\n");
> +                       return ret;
> +               }
>         }
>
>         if (priv->restore_needed) {
> --
> 2.29.0
>

Kind regards
Uffe