It is common to read a device-tree property from the node associated with a device. Add convenience functions to do this so that drivers do not need to deal with the difference between live tree and flat tree access methods.
Signed-off-by: Simon Glass sjg@chromium.org ---
drivers/core/Makefile | 2 +- drivers/core/of_dev.c | 55 +++++++++++++++++++++++++++++++++++++++++ include/dm/of_dev.h | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 124 insertions(+), 1 deletion(-) create mode 100644 drivers/core/of_dev.c create mode 100644 include/dm/of_dev.h
diff --git a/drivers/core/Makefile b/drivers/core/Makefile index 6d7040c2603..be1e9da55c0 100644 --- a/drivers/core/Makefile +++ b/drivers/core/Makefile @@ -11,4 +11,4 @@ obj-$(CONFIG_$(SPL_)SIMPLE_BUS) += simple-bus.o obj-$(CONFIG_DM) += dump.o obj-$(CONFIG_$(SPL_)REGMAP) += regmap.o obj-$(CONFIG_$(SPL_)SYSCON) += syscon-uclass.o -obj-$(CONFIG_OF_CONTROL) += of_extra.o of_ref.o +obj-$(CONFIG_OF_CONTROL) += of_dev.o of_extra.o of_ref.o diff --git a/drivers/core/of_dev.c b/drivers/core/of_dev.c new file mode 100644 index 00000000000..0474ef1408b --- /dev/null +++ b/drivers/core/of_dev.c @@ -0,0 +1,55 @@ +/* + * Copyright (c) 2017 Google, Inc + * Written by Simon Glass sjg@chromium.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <dm/of_dev.h> +#include <dm/of_ref.h> + +/** + * dev_of_node_ref() - get the DT node reference associated with a udevice + * + * TODO(sjg@chromium.org): Once dev->of_offset is dropped, we can simplify + * this function. For now it has to look at both of_node and of_offset. + * + * @dev: device to check + * @return reference of the the device's DT node + */ +of_node_ref dev_of_node_ref(struct udevice *dev) +{ +#ifdef CONFIG_OF_LIVE + return dev->node_ref; +#else + return of_offset_to_ref(dev->of_offset); +#endif +} + +int dev_read_u32_defaut(struct udevice *dev, const char *propname, int def) +{ + u32 val; + + if (of_ref_read_u32(dev_of_node_ref(dev), propname, &val)) + return def; + + return val; +} + +const char *dev_read_string(struct udevice *dev, const char *propname) +{ + return of_ref_read_string(dev_of_node_ref(dev), propname); +} + +bool dev_read_bool(struct udevice *dev, const char *propname) +{ + return of_ref_read_bool(dev_of_node_ref(dev), propname); +} + +of_node_ref dev_find_subnode(struct udevice *dev, + const char *subnode_name) +{ + return of_ref_find_subnode(dev_of_node_ref(dev), subnode_name); +} diff --git a/include/dm/of_dev.h b/include/dm/of_dev.h new file mode 100644 index 00000000000..e7962088106 --- /dev/null +++ b/include/dm/of_dev.h @@ -0,0 +1,68 @@ +/* + * Function to read values from the device tree node attached to a udevice. + * + * Copyright (c) 2017 Google, Inc + * Written by Simon Glass sjg@chromium.org + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#ifndef _DM_OF_DEV_H +#define _DM_OF_DEV_H + +#include <dm/of_ref.h> + +#ifdef CONFIG_OF_LIVE +static inline const struct device_node *dev_of_node(struct udevice *dev) +{ + return of_ref_to_node(dev->node_ref); +} +#else +static inline const struct device_node *dev_of_node(struct udevice *dev) +{ + return NULL; +} +#endif + +of_node_ref dev_of_node_ref(struct udevice *dev); + +/** + * dev_read_u32_defaut() - read a 32-bit integer from a device's DT property + * + * @dev: device to read DT property from + * @propname: name of the property to read from + * @def: default value to return if the property has no value + * @return property value, or @def if not found + */ +int dev_read_u32_defaut(struct udevice *dev, const char *propname, int def); + +/** + * dev_read_string() - Read a string from a device's DT property + * + * @dev: device to read DT property from + * @propname: name of the property to read + * @return string from property value, or NULL if there is no such property + */ +const char *dev_read_string(struct udevice *dev, const char *propname); + +/** + * dev_read_bool() - read a boolean value from a device's DT property + * + * @dev: device to read DT property from + * @propname: name of property to read + * @return true if property is present (meaning true), false if not present + */ +bool dev_read_bool(struct udevice *dev, const char *propname); + +/** + * dev_find_subnode() - find a named subnode of a device + * + * @dev: device whose DT node contains the subnode + * @subnode_name: name of subnode to find + * @return reference to subnode (which can be invalid if there is no such + * subnode) + */ +of_node_ref dev_find_subnode(struct udevice *dev, + const char *subbnode_name); + +#endif