[PATCH] mux: mmio: Do not use syscon helper to build regmap
From: Andrew Davis
Date: Thu Jan 23 2025 - 13:21:14 EST
The syscon helper device_node_to_regmap() is used to fetch a regmap
registered to a device node. It also currently creates this regmap
if the node did not already have a regmap associated with it. This
should only be used on "syscon" nodes. This driver is not such a
device and instead uses device_node_to_regmap() on its own node as
a hacky way to create a regmap for itself.
This will not work going forward and so we should create our regmap
the normal way by defining our regmap_config, fetching our memory
resource, then using the normal regmap_init_mmio() function.
Signed-off-by: Andrew Davis <afd@xxxxxx>
---
drivers/mux/mmio.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/drivers/mux/mmio.c b/drivers/mux/mmio.c
index 30a952c34365f..278efdc480777 100644
--- a/drivers/mux/mmio.c
+++ b/drivers/mux/mmio.c
@@ -33,6 +33,12 @@ static const struct of_device_id mux_mmio_dt_ids[] = {
};
MODULE_DEVICE_TABLE(of, mux_mmio_dt_ids);
+static const struct regmap_config mux_mmio_regmap_cfg = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+};
+
static int mux_mmio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -40,6 +46,7 @@ static int mux_mmio_probe(struct platform_device *pdev)
struct regmap_field **fields;
struct mux_chip *mux_chip;
struct regmap *regmap;
+ void __iomem *base;
int num_fields;
int ret;
int i;
@@ -47,7 +54,11 @@ static int mux_mmio_probe(struct platform_device *pdev)
if (of_device_is_compatible(np, "mmio-mux")) {
regmap = syscon_node_to_regmap(np->parent);
} else {
- regmap = device_node_to_regmap(np);
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ regmap = ERR_PTR(-ENODEV);
+ else
+ regmap = regmap_init_mmio(dev, base, &mux_mmio_regmap_cfg);
/* 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);
--
2.39.2