Re: [PATCH 2/2] PCI: rcar-host: add support for optional regulators

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Wolfram,

On Wed, May 10, 2023 at 8:59 AM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
> The KingFisher board has regulators. They just need to be en-/disabled,
> so we can leave the handling to devm.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>
> Changes since RFC:
> * add 12v regulator
> * add comment about the order of enabling the regulators
> * use a for-loop to iterate over the regulators

Thanks for the update!

> --- a/drivers/pci/controller/pcie-rcar-host.c
> +++ b/drivers/pci/controller/pcie-rcar-host.c
> @@ -29,6 +29,7 @@
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
>  #include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
>
>  #include "pcie-rcar.h"
>
> @@ -974,13 +975,18 @@ static const struct of_device_id rcar_pcie_of_match[] = {
>         {},
>  };
>
> +/* Design note 346 from Linear Technology says order is not important */
> +static const char * const rcar_pcie_supplies[] = {
> +       "vpcie12v", "vpcie3v3", "vpcie1v5"
> +};
> +
>  static int rcar_pcie_probe(struct platform_device *pdev)
>  {
>         struct device *dev = &pdev->dev;
>         struct rcar_pcie_host *host;
>         struct rcar_pcie *pcie;
>         u32 data;
> -       int err;
> +       int i, err;

unsigned int i?

>         struct pci_host_bridge *bridge;

The (lack of) reverse-Xmas-tree ordering is hurting my OCD, but that's
not your fault...

> @@ -992,6 +998,13 @@ static int rcar_pcie_probe(struct platform_device *pdev)
>         pcie->dev = dev;
>         platform_set_drvdata(pdev, host);
>
> +       for (i = 0; i < ARRAY_SIZE(rcar_pcie_supplies); i++) {
> +               err = devm_regulator_get_enable_optional(dev, rcar_pcie_supplies[i]);
> +               if (err < 0 && err != -ENODEV)
> +                       dev_err_probe(dev, err, "error enabling regulator %s\n",
> +                                     rcar_pcie_supplies[i]);

Shouldn't this return, and propagate the error code upstream?

> +       }
> +
>         pm_runtime_enable(pcie->dev);
>         err = pm_runtime_get_sync(pcie->dev);
>         if (err < 0) {

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds