On Tue, 04 Jun 2019, Robert Hancock wrote:
> Previously the MFD core supported assigning OF nodes to created MFD
> devices, but relied solely on matching the of_compatible string. This
> would result in devices being potentially assigned the wrong node if
> there are multiple devices with the same compatible string within a
> multifunction device.
>
> Add support for matching the full name of the node in the MFD cell
> definition, so that we can match against a specific instance of a
> device. If this is not specified, we match just based on the
> compatible string, as before.
>
> Signed-off-by: Robert Hancock <hanc...@sedsystems.ca>
> ---
> drivers/mfd/mfd-core.c | 5 ++++-
> include/linux/mfd/core.h | 3 +++
> 2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
> index 1ade4c8..74bc895 100644
> --- a/drivers/mfd/mfd-core.c
> +++ b/drivers/mfd/mfd-core.c
> @@ -177,7 +177,10 @@ static int mfd_add_device(struct device *parent, int id,
>
> if (parent->of_node && cell->of_compatible) {
> for_each_child_of_node(parent->of_node, np) {
> - if (of_device_is_compatible(np, cell->of_compatible)) {
> + if (of_device_is_compatible(np, cell->of_compatible) &&
> + (!cell->of_full_name ||
> + !strcmp(cell->of_full_name,
> + of_node_full_name(np)))) {
> pdev->dev.of_node = np;
> break;
That is some ugly, squashed up code.
If we end up accepting this, I suggest flattening this out a bit.
... but we'll cross that bridge when we come to it.
> diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h
> index 99c0395..470f6cb 100644
> --- a/include/linux/mfd/core.h
> +++ b/include/linux/mfd/core.h
> @@ -55,6 +55,9 @@ struct mfd_cell {
> */
> const char *of_compatible;
>
> + /* Optionally match against a specific device of a given type */
> + const char *of_full_name;
> +
Can you give me an example for when this might be useful?
> /* Matches ACPI */
> const struct mfd_cell_acpi_match *acpi_match;
>
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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