mfd: syscon: Set regmap max_register in of_syscon_register

Determine the regmap max_register configuration from the io resource size
and the reg-io-width device tree property.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index b7aabee..99e8f88 100644 (file)
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -50,6 +50,7 @@ static struct syscon *of_syscon_register(struct device_node *np)
        u32 reg_io_width;
        int ret;
        struct regmap_config syscon_config = syscon_regmap_config;
+       struct resource res;
 
        if (!of_device_is_compatible(np, "syscon"))
                return ERR_PTR(-EINVAL);
@@ -58,7 +59,12 @@ static struct syscon *of_syscon_register(struct device_node *np)
        if (!syscon)
                return ERR_PTR(-ENOMEM);
 
-       base = of_iomap(np, 0);
+       if (of_address_to_resource(np, 0, &res)) {
+               ret = -ENOMEM;
+               goto err_map;
+       }
+
+       base = ioremap(res.start, resource_size(&res));
        if (!base) {
                ret = -ENOMEM;
                goto err_map;
@@ -81,6 +87,7 @@ static struct syscon *of_syscon_register(struct device_node *np)
 
        syscon_config.reg_stride = reg_io_width;
        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);
        if (IS_ERR(regmap)) {