dev_read_u32_default() always returns something even when the property is missing. So, it is impossible to do nothing in the case. One solution is to use ofnode_read_u32() instead, but adding dev_read_u32() will be helpful.
BTW, Linux has an equvalent function, device_property_read_u32(); it is clearer that it reads a property. I cannot understand the behavior of dev_read_u32() from its name.
Signed-off-by: Masahiro Yamada yamada.masahiro@socionext.com ---
BTW, I do not understand why we want *_default helpers. It is pretty easy to do equivalent without _default.
priv->val = default; /* default in case property is missing */ dev_read_u32(dev, "foo-property", &priv->val);
On the other hand, if we want to do nothing for missing property, we will end up with clumsy code.
/* we do not want to overwrite priv->val if property is missing */ if (dev_read_bool(dev, "foo-property") { /* default value '0' will not be used anyway */ priv->val = dev_read_u32_default(dev, "foo-property", 0); }
One more BTW, it was just painful to write equivalent code twice for CONFIG_DM_DEV_READ_INLINE.
drivers/core/read.c | 5 +++++ include/dm/read.h | 16 ++++++++++++++++ 2 files changed, 21 insertions(+)
diff --git a/drivers/core/read.c b/drivers/core/read.c index 5d440ce..e027041 100644 --- a/drivers/core/read.c +++ b/drivers/core/read.c @@ -10,6 +10,11 @@ #include <mapmem.h> #include <dm/of_access.h>
+int dev_read_u32(struct udevice *dev, const char *propname, u32 *outp) +{ + return ofnode_read_u32(dev_ofnode(dev), propname, outp); +} + int dev_read_u32_default(struct udevice *dev, const char *propname, int def) { return ofnode_read_u32_default(dev_ofnode(dev), propname, def); diff --git a/include/dm/read.h b/include/dm/read.h index 8114037..5cacec8 100644 --- a/include/dm/read.h +++ b/include/dm/read.h @@ -46,6 +46,16 @@ static inline bool dev_of_valid(struct udevice *dev)
#ifndef CONFIG_DM_DEV_READ_INLINE /** + * dev_read_u32() - 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 + * @outp: place to put value (if found) + * @return 0 if OK, -ve on error + */ +int dev_read_u32(struct udevice *dev, const char *propname, u32 *outp); + +/** * dev_read_u32_default() - read a 32-bit integer from a device's DT property * * @dev: device to read DT property from @@ -412,6 +422,12 @@ int dev_read_resource_byname(struct udevice *dev, const char *name,
#else /* CONFIG_DM_DEV_READ_INLINE is enabled */
+static inline int dev_read_u32(struct udevice *dev, + const char *propname, u32 *outp) +{ + return ofnode_read_u32(dev_ofnode(dev), propname, outp); +} + static inline int dev_read_u32_default(struct udevice *dev, const char *propname, int def) {