Re: [PATCH v21 3/4] PCI: microchip: Add host driver for Microchip PCIe controller

[Bjorn Helgaas <helgaas@kernel.org>]

On Mon, Jan 25, 2021 at 04:29:33PM +0000, daire.mcnamara@microchip.com wrote:
> From: Daire McNamara <daire.mcnamara@microchip.com>
> 
> Add support for the Microchip PolarFire PCIe controller when
> configured in host (Root Complex) mode.
> ...

> +static inline struct clk *mc_pcie_init_clk(struct device *dev, const char *id)
> +{
> +	struct clk *clk;
> +	int ret;
> +
> +	clk = devm_clk_get_optional(dev, id);
> +	if (IS_ERR(clk))
> +		return clk;
> +	if (!clk)
> +		return clk;
> +
> +	ret = clk_prepare_enable(clk);
> +	if (ret)
> +		return ERR_PTR(ret);
> +
> +	devm_add_action_or_reset(dev, (void (*) (void *))clk_disable_unprepare, clk);

Internal sashiko review while backporting b12341b98d5a ("PCI: meson:
Propagate devm_add_action_or_reset() failure") suggests the same bug
here as was fixed by b12341b98d5a, e.g., failure of
devm_add_action_or_reset() might result in trying to initialize the
controller while clock is disabled.

> +
> +	return clk;
> +}