[PATCH v2 5/5] simplefb: add clock handling code

Geert Uytterhoeven geert at linux-m68k.org
Mon Oct 6 03:15:04 PDT 2014


On Fri, Oct 3, 2014 at 1:52 PM, Hans de Goede <hdegoede at redhat.com> wrote:
> +static void
> +simplefb_clocks_init(struct platform_device *pdev, struct list_head *list)
> +{
> +       struct device_node *np = pdev->dev.of_node;
> +       int clock_count, i;
> +
> +       INIT_LIST_HEAD(list);
> +
> +       if (dev_get_platdata(&pdev->dev) || !np)
> +               return;
> +
> +       clock_count = of_clk_get_parent_count(np);
> +       for (i = 0; i < clock_count; i++) {
> +               struct simplefb_clock *entry;
> +               struct clk *clock = of_clk_get(np, i);
> +               int ret;
> +
> +               if (IS_ERR(clock)) {
> +                       dev_err(&pdev->dev, "%s: clock %d not found: %ld\n",
> +                              __func__, i, PTR_ERR(clock));
> +                       continue;
> +               }
> +
> +               ret = clk_prepare_enable(clock);
> +               if (ret) {
> +                       dev_err(&pdev->dev,
> +                               "%s: failed to enable clock %d: %d\n",
> +                              __func__, i, ret);
> +                       clk_put(clock);
> +                       continue;
> +               }
> +
> +               entry = kzalloc(sizeof(struct simplefb_clock), GFP_KERNEL);
> +               if (!entry) {
> +                       clk_disable_unprepare(clock);
> +                       clk_put(clock);
> +                       continue;
> +               }

I'd allocate memory first, to avoid calling clk_disable_unprepare() (which
will kill your display) if memory allocation fails.

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at 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



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