[PATCH v2] mfd: syscon: allow to register syscon with a device

[Philipp Zabel <p.zabel@pengutronix.de>]

Commit bdb0066df96e ("mfd: syscon: Decouple syscon interface from platform
devices") added the possibility to register syscon devices without
associated platform device. This also removed regmap debugfs facilities,
which don't work without a device. Since there is no replacement, this
patch allows again to register syscon regions with an associated device
where that this device exists anyway.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
Changes since v1:
 - Rebased onto for-mfd-next
---
 drivers/mfd/syscon.c       | 10 ++++++++--
 include/linux/mfd/syscon.h | 10 ++++++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index 2f2225e..fe67fb0 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -42,7 +42,7 @@ static const struct regmap_config syscon_regmap_config = {
 	.reg_stride = 4,
 };
 
-static struct syscon *of_syscon_register(struct device_node *np)
+struct syscon *syscon_register(struct device *dev, struct device_node *np)
 {
 	struct syscon *syscon;
 	struct regmap *regmap;
@@ -89,7 +89,7 @@ static struct syscon *of_syscon_register(struct device_node *np)
 	syscon_config.val_bits = reg_io_width * 8;
 	syscon_config.max_register = resource_size(&res) - reg_io_width;
 
-	regmap = regmap_init_mmio(NULL, base, &syscon_config);
+	regmap = regmap_init_mmio(dev, base, &syscon_config);
 	if (IS_ERR(regmap)) {
 		pr_err("regmap init failed\n");
 		ret = PTR_ERR(regmap);
@@ -111,6 +111,12 @@ err_map:
 	kfree(syscon);
 	return ERR_PTR(ret);
 }
+EXPORT_SYMBOL_GPL(syscon_register);
+
+static struct syscon *of_syscon_register(struct device_node *np)
+{
+	return syscon_register(NULL, np);
+}
 
 struct regmap *syscon_node_to_regmap(struct device_node *np)
 {
diff --git a/include/linux/mfd/syscon.h b/include/linux/mfd/syscon.h
index 1088149..e26037c 100644
--- a/include/linux/mfd/syscon.h
+++ b/include/linux/mfd/syscon.h
@@ -17,10 +17,14 @@
 
 #include <linux/err.h>
 
+struct device;
 struct device_node;
+struct syscon;
 
 #ifdef CONFIG_MFD_SYSCON
 extern struct regmap *syscon_node_to_regmap(struct device_node *np);
+extern struct syscon *syscon_register(struct device *dev,
+				      struct device_node *np);
 extern struct regmap *syscon_regmap_lookup_by_compatible(const char *s);
 extern struct regmap *syscon_regmap_lookup_by_pdevname(const char *s);
 extern struct regmap *syscon_regmap_lookup_by_phandle(
@@ -32,6 +36,12 @@ static inline struct regmap *syscon_node_to_regmap(struct device_node *np)
 	return ERR_PTR(-ENOTSUPP);
 }
 
+static struct syscon *syscon_register(struct device *dev,
+				      struct device_node *np)
+{
+	return ERR_PTR(-ENOTSUPP);
+}
+
 static inline struct regmap *syscon_regmap_lookup_by_compatible(const char *s)
 {
 	return ERR_PTR(-ENOTSUPP);
-- 
2.7.0