The DT binding for the reg-mux compatible states it can be used when the "parent device of mux controller is not syscon device". It also allows for a reg property. When the reg property is provided, use that to identify the address space for this mux. If not provided fallback to using the parent device as a regmap provider. While here use dev_err_probe() in the error path to prevent printing a message on probe defer which now can happen in extra ways. Signed-off-by: Andrew Davis <afd@xxxxxx> Reviewed-by: Nishanth Menon <nm@xxxxxx> Acked-by: Peter Rosin <peda@xxxxxxxxxx> --- Changes from v5: - Rebased on next-20240104 Changes from v4: - Shorten comment and code lines - Remove extra ret assignment Changes from v3: - Check for probe defer Changes from v2: - Rebased on v6.6-rc1 Changes from v1: - Flip logic as suggested in v1[0] [0] https://lore.kernel.org/lkml/1c27d9d4-b1cc-c158-90f7-f7e47e02c424@xxxxxx/T/ drivers/mux/mmio.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/mux/mmio.c b/drivers/mux/mmio.c index fd1d121a584ba..30a952c34365f 100644 --- a/drivers/mux/mmio.c +++ b/drivers/mux/mmio.c @@ -44,15 +44,20 @@ static int mux_mmio_probe(struct platform_device *pdev) int ret; int i; - if (of_device_is_compatible(np, "mmio-mux")) + if (of_device_is_compatible(np, "mmio-mux")) { regmap = syscon_node_to_regmap(np->parent); - else - regmap = dev_get_regmap(dev->parent, NULL) ?: ERR_PTR(-ENODEV); - if (IS_ERR(regmap)) { - ret = PTR_ERR(regmap); - dev_err(dev, "failed to get regmap: %d\n", ret); - return ret; + } else { + regmap = device_node_to_regmap(np); + /* Fallback to checking the parent node on "real" errors. */ + if (IS_ERR(regmap) && regmap != ERR_PTR(-EPROBE_DEFER)) { + regmap = dev_get_regmap(dev->parent, NULL); + if (!regmap) + regmap = ERR_PTR(-ENODEV); + } } + if (IS_ERR(regmap)) + return dev_err_probe(dev, PTR_ERR(regmap), + "failed to get regmap\n"); ret = of_property_count_u32_elems(np, "mux-reg-masks"); if (ret == 0 || ret % 2) -- 2.39.2
