diff options
| author | Sanchayan Maity <maitysanchayan@gmail.com> | 2016-03-04 17:01:19 +0530 |
|---|---|---|
| committer | Stefan Agner <stefan.agner@toradex.com> | 2016-03-09 13:34:01 -0800 |
| commit | 0c2d2e753259d8b84fa0cd3dfc5889e388051025 (patch) | |
| tree | 9bdd05ddbd292b5bb183c09c625cbbe937316e7e /drivers/mfd | |
| parent | cac87642fd3e8239af3a20541232892366728195 (diff) | |
mfd: syscon: Introduce syscon_regmap_read_from_offset
Currently syscon does not provide an abstraction to access a
register from syscon reference like below
ocotp-cfg1 = <&ocotp 0x20>
syscon_regmap_read_from_offset provides a generic abstraction to
access a register from syscon reference as above. It allows to
specify the node and node name of phandle reference, reading the
offset from the node entry and providing the value from the offset
in the register map.
Signed-off-by: Sanchayan Maity <maitysanchayan@gmail.com>
Diffstat (limited to 'drivers/mfd')
| -rw-r--r-- | drivers/mfd/syscon.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c index 176bf0fa2685..34d71de1bc1c 100644 --- a/drivers/mfd/syscon.c +++ b/drivers/mfd/syscon.c @@ -116,6 +116,36 @@ struct regmap *syscon_node_to_regmap(struct device_node *np) } EXPORT_SYMBOL_GPL(syscon_node_to_regmap); +int syscon_regmap_read_from_offset(struct device_node *np, + const char *s, unsigned int *val) +{ + struct of_phandle_args pargs; + struct regmap *regmap; + int offset; + int ret; + + if (!np) + return -ENODEV; + + ret = of_parse_phandle_with_fixed_args(np, s, 1, 0, &pargs); + if (ret) + return ret; + + regmap = syscon_node_to_regmap(pargs.np); + if (IS_ERR(regmap)) { + of_node_put(pargs.np); + return PTR_ERR(regmap); + } + + offset = pargs.args[0]; + of_node_put(pargs.np); + + ret = regmap_read(regmap, offset, val); + + return ret; +} +EXPORT_SYMBOL_GPL(syscon_regmap_read_from_offset); + struct regmap *syscon_regmap_lookup_by_compatible(const char *s) { struct device_node *syscon_np; |