| Message ID | 20220323091810.329217-2-clement.leger@bootlin.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | introduce fwnode in the I2C subsystem | expand |
Hi Clément, Thanks for the set. On Wed, Mar 23, 2022 at 10:18:04AM +0100, Clément Léger wrote: > Add fwnode_property_read_string_index() function which allows to > retrieve a string from an array by its index. This function is the > equivalent of of_property_read_string_index() but for fwnode support. > A .property_read_string_index callback is added to fwnode_ops to avoid > doing a full allocation of an array just to retrieve one value. > > Signed-off-by: Clément Léger <clement.leger@bootlin.com> > --- > drivers/base/property.c | 26 ++++++++++++++++++++++++++ > include/linux/fwnode.h | 6 ++++++ > include/linux/property.h | 3 +++ > 3 files changed, 35 insertions(+) > > diff --git a/drivers/base/property.c b/drivers/base/property.c > index e6497f6877ee..a8dd6e496a1d 100644 > --- a/drivers/base/property.c > +++ b/drivers/base/property.c > @@ -451,6 +451,32 @@ int fwnode_property_match_string(const struct fwnode_handle *fwnode, > } > EXPORT_SYMBOL_GPL(fwnode_property_match_string); > > +/** > + * fwnode_property_read_string_index - read a string in an array using an index > + * @fwnode: Firmware node to get the property of > + * @propname: Name of the property holding the array > + * @index: Index of the string to look for > + * @string: Pointer to the string if found > + * > + * Find a string by a given index in a string array and if it is found return > + * the string value in @string. > + * > + * Return: %0 if the property was found (success), > + * %-EINVAL if given arguments are not valid, > + * %-ENODATA if the property does not have a value, > + * %-EPROTO if the property is not an array of strings, > + * %-ENXIO if no suitable firmware interface is present. > + */ > +int fwnode_property_read_string_index(const struct fwnode_handle *fwnode, > + const char *propname, int index, > + const char **string) > +{ > + return fwnode_call_int_op(fwnode, property_read_string_index, propname, > + index, > + string); > +} > +EXPORT_SYMBOL_GPL(fwnode_property_read_string_index); > + > /** > * fwnode_property_get_reference_args() - Find a reference with arguments > * @fwnode: Firmware node where to look for the reference > diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h > index 3a532ba66f6c..71ba8f53cf1e 100644 > --- a/include/linux/fwnode.h > +++ b/include/linux/fwnode.h > @@ -93,6 +93,9 @@ struct fwnode_reference_args { > * success, a negative error code otherwise. > * @property_read_string_array: Read an array of string properties. Return zero > * on success, a negative error code otherwise. > + * @property_read_string_index: Read a string from a string array using an > + * index. Return zero on success, a negative error > + * code otherwise. > * @get_name: Return the name of an fwnode. > * @get_name_prefix: Get a prefix for a node (for printing purposes). > * @get_parent: Return the parent of an fwnode. > @@ -123,6 +126,9 @@ struct fwnode_operations { > (*property_read_string_array)(const struct fwnode_handle *fwnode_handle, > const char *propname, const char **val, > size_t nval); > + int (*property_read_string_index)(const struct fwnode_handle *fwnode, > + const char *propname, int index, > + const char **string); Could this instead be done by adding an index argument to the property_read_string_array? The ACPI case is a bit more work but it guess it could be implemented later as part of a more general cleanup there. > const char *(*get_name)(const struct fwnode_handle *fwnode); > const char *(*get_name_prefix)(const struct fwnode_handle *fwnode); > struct fwnode_handle *(*get_parent)(const struct fwnode_handle *fwnode); > diff --git a/include/linux/property.h b/include/linux/property.h > index 7399a0b45f98..a033920eb10a 100644 > --- a/include/linux/property.h > +++ b/include/linux/property.h > @@ -70,6 +70,9 @@ int fwnode_property_read_string_array(const struct fwnode_handle *fwnode, > size_t nval); > int fwnode_property_read_string(const struct fwnode_handle *fwnode, > const char *propname, const char **val); > +int fwnode_property_read_string_index(const struct fwnode_handle *fwnode, > + const char *propname, int index, > + const char **string); > int fwnode_property_match_string(const struct fwnode_handle *fwnode, > const char *propname, const char *string); > int fwnode_property_get_reference_args(const struct fwnode_handle *fwnode,
Le Wed, 23 Mar 2022 13:34:07 +0200, Sakari Ailus <sakari.ailus@linux.intel.com> a écrit : > > * @get_parent: Return the parent of an fwnode. > > @@ -123,6 +126,9 @@ struct fwnode_operations { > > (*property_read_string_array)(const struct fwnode_handle *fwnode_handle, > > const char *propname, const char **val, > > size_t nval); > > + int (*property_read_string_index)(const struct fwnode_handle *fwnode, > > + const char *propname, int index, > > + const char **string); > > Could this instead be done by adding an index argument to the > property_read_string_array? Hi Sakari, I guess I could do that. Do you expect the string pointer to be returned in "val" ? Guess a -1 index would mean that we don't care about the index but want the array to be returned. And if index is specified, nval will be ignored. > > The ACPI case is a bit more work but it guess it could be implemented later > as part of a more general cleanup there.
Hi Clément, On Wed, Mar 23, 2022 at 12:39:02PM +0100, Clément Léger wrote: > Le Wed, 23 Mar 2022 13:34:07 +0200, > Sakari Ailus <sakari.ailus@linux.intel.com> a écrit : > > > > * @get_parent: Return the parent of an fwnode. > > > @@ -123,6 +126,9 @@ struct fwnode_operations { > > > (*property_read_string_array)(const struct fwnode_handle *fwnode_handle, > > > const char *propname, const char **val, > > > size_t nval); > > > + int (*property_read_string_index)(const struct fwnode_handle *fwnode, > > > + const char *propname, int index, > > > + const char **string); > > > > Could this instead be done by adding an index argument to the > > property_read_string_array? > > Hi Sakari, > > I guess I could do that. Do you expect the string pointer to be > returned in "val" ? Guess a -1 index would mean that we don't care > about the index but want the array to be returned. And if index is > specified, nval will be ignored. I'd keep the behaviour the same independently of the value of index.
diff --git a/drivers/base/property.c b/drivers/base/property.c index e6497f6877ee..a8dd6e496a1d 100644 --- a/drivers/base/property.c +++ b/drivers/base/property.c @@ -451,6 +451,32 @@ int fwnode_property_match_string(const struct fwnode_handle *fwnode, } EXPORT_SYMBOL_GPL(fwnode_property_match_string); +/** + * fwnode_property_read_string_index - read a string in an array using an index + * @fwnode: Firmware node to get the property of + * @propname: Name of the property holding the array + * @index: Index of the string to look for + * @string: Pointer to the string if found + * + * Find a string by a given index in a string array and if it is found return + * the string value in @string. + * + * Return: %0 if the property was found (success), + * %-EINVAL if given arguments are not valid, + * %-ENODATA if the property does not have a value, + * %-EPROTO if the property is not an array of strings, + * %-ENXIO if no suitable firmware interface is present. + */ +int fwnode_property_read_string_index(const struct fwnode_handle *fwnode, + const char *propname, int index, + const char **string) +{ + return fwnode_call_int_op(fwnode, property_read_string_index, propname, + index, + string); +} +EXPORT_SYMBOL_GPL(fwnode_property_read_string_index); + /** * fwnode_property_get_reference_args() - Find a reference with arguments * @fwnode: Firmware node where to look for the reference diff --git a/include/linux/fwnode.h b/include/linux/fwnode.h index 3a532ba66f6c..71ba8f53cf1e 100644 --- a/include/linux/fwnode.h +++ b/include/linux/fwnode.h @@ -93,6 +93,9 @@ struct fwnode_reference_args { * success, a negative error code otherwise. * @property_read_string_array: Read an array of string properties. Return zero * on success, a negative error code otherwise. + * @property_read_string_index: Read a string from a string array using an + * index. Return zero on success, a negative error + * code otherwise. * @get_name: Return the name of an fwnode. * @get_name_prefix: Get a prefix for a node (for printing purposes). * @get_parent: Return the parent of an fwnode. @@ -123,6 +126,9 @@ struct fwnode_operations { (*property_read_string_array)(const struct fwnode_handle *fwnode_handle, const char *propname, const char **val, size_t nval); + int (*property_read_string_index)(const struct fwnode_handle *fwnode, + const char *propname, int index, + const char **string); const char *(*get_name)(const struct fwnode_handle *fwnode); const char *(*get_name_prefix)(const struct fwnode_handle *fwnode); struct fwnode_handle *(*get_parent)(const struct fwnode_handle *fwnode); diff --git a/include/linux/property.h b/include/linux/property.h index 7399a0b45f98..a033920eb10a 100644 --- a/include/linux/property.h +++ b/include/linux/property.h @@ -70,6 +70,9 @@ int fwnode_property_read_string_array(const struct fwnode_handle *fwnode, size_t nval); int fwnode_property_read_string(const struct fwnode_handle *fwnode, const char *propname, const char **val); +int fwnode_property_read_string_index(const struct fwnode_handle *fwnode, + const char *propname, int index, + const char **string); int fwnode_property_match_string(const struct fwnode_handle *fwnode, const char *propname, const char *string); int fwnode_property_get_reference_args(const struct fwnode_handle *fwnode,
Add fwnode_property_read_string_index() function which allows to retrieve a string from an array by its index. This function is the equivalent of of_property_read_string_index() but for fwnode support. A .property_read_string_index callback is added to fwnode_ops to avoid doing a full allocation of an array just to retrieve one value. Signed-off-by: Clément Léger <clement.leger@bootlin.com> --- drivers/base/property.c | 26 ++++++++++++++++++++++++++ include/linux/fwnode.h | 6 ++++++ include/linux/property.h | 3 +++ 3 files changed, 35 insertions(+)