Linux-libre 4.5-gnu

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index 176bf0fa2..b7aabeefa 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -47,6 +47,7 @@ static struct syscon *of_syscon_register(struct device_node *np)
 	struct syscon *syscon;
 	struct regmap *regmap;
 	void __iomem *base;
+	u32 reg_io_width;
 	int ret;
 	struct regmap_config syscon_config = syscon_regmap_config;
 
@@ -69,6 +70,18 @@ static struct syscon *of_syscon_register(struct device_node *np)
 	 else if (of_property_read_bool(np, "little-endian"))
 		syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
 
+	/*
+	 * search for reg-io-width property in DT. If it is not provided,
+	 * default to 4 bytes. regmap_init_mmio will return an error if values
+	 * are invalid so there is no need to check them here.
+	 */
+	ret = of_property_read_u32(np, "reg-io-width", &reg_io_width);
+	if (ret)
+		reg_io_width = 4;
+
+	syscon_config.reg_stride = reg_io_width;
+	syscon_config.val_bits = reg_io_width * 8;
+
 	regmap = regmap_init_mmio(NULL, base, &syscon_config);
 	if (IS_ERR(regmap)) {
 		pr_err("regmap init failed\n");