This adds following helper routines:
- of_property_read_u8_array()
- of_property_read_u16_array()
- of_property_read_u8()
- of_property_read_u16()
First two actually share most of the code with of_property_read_u32_array(), so
the common part is taken out into a macro, which can be used by all three
*_array() routines.
Signed-off-by: Viresh Kumar <[email protected]>
---
drivers/of/base.c | 73 +++++++++++++++++++++++++++++++++++++++++++-----------
include/linux/of.h | 30 ++++++++++++++++++++++
2 files changed, 89 insertions(+), 14 deletions(-)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index 38892a9..446fe7f 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -670,6 +670,64 @@ struct device_node *of_find_node_by_phandle(phandle handle)
}
EXPORT_SYMBOL(of_find_node_by_phandle);
+#define of_property_read_array(_np, _pname, _out, _sz, _type) \
+ struct property *_prop = of_find_property(_np, _pname, NULL); \
+ const __be32 *_val; \
+ \
+ if (!_prop) \
+ return -EINVAL; \
+ if (!_prop->value) \
+ return -ENODATA; \
+ if ((_sz * sizeof(*_out)) > _prop->length) \
+ return -EOVERFLOW; \
+ \
+ _val = _prop->value; \
+ while (_sz--) \
+ *_out++ = (_type)be32_to_cpup(_val++); \
+ return 0;
+
+/**
+ * of_property_read_u8_array - Find and read an array of u8 from a property.
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_value: pointer to return value, modified only if return value is 0.
+ *
+ * Search for a property in a device node and read 8-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_value is modified only if a valid u8 value can be decoded.
+ */
+int of_property_read_u8_array(const struct device_node *np,
+ const char *propname, u8 *out_values, size_t sz)
+{
+ of_property_read_array(np, propname, out_values, sz, u8);
+}
+EXPORT_SYMBOL_GPL(of_property_read_u8_array);
+
+/**
+ * of_property_read_u16_array - Find and read an array of u16 from a property.
+ *
+ * @np: device node from which the property value is to be read.
+ * @propname: name of the property to be searched.
+ * @out_value: pointer to return value, modified only if return value is 0.
+ *
+ * Search for a property in a device node and read 16-bit value(s) from
+ * it. Returns 0 on success, -EINVAL if the property does not exist,
+ * -ENODATA if property does not have a value, and -EOVERFLOW if the
+ * property data isn't large enough.
+ *
+ * The out_value is modified only if a valid u16 value can be decoded.
+ */
+int of_property_read_u16_array(const struct device_node *np,
+ const char *propname, u16 *out_values, size_t sz)
+{
+ of_property_read_array(np, propname, out_values, sz, u16);
+}
+EXPORT_SYMBOL_GPL(of_property_read_u16_array);
+
/**
* of_property_read_u32_array - Find and read an array of 32 bit integers
* from a property.
@@ -689,20 +747,7 @@ int of_property_read_u32_array(const struct device_node *np,
const char *propname, u32 *out_values,
size_t sz)
{
- struct property *prop = of_find_property(np, propname, NULL);
- const __be32 *val;
-
- if (!prop)
- return -EINVAL;
- if (!prop->value)
- return -ENODATA;
- if ((sz * sizeof(*out_values)) > prop->length)
- return -EOVERFLOW;
-
- val = prop->value;
- while (sz--)
- *out_values++ = be32_to_cpup(val++);
- return 0;
+ of_property_read_array(np, propname, out_values, sz, u32);
}
EXPORT_SYMBOL_GPL(of_property_read_u32_array);
diff --git a/include/linux/of.h b/include/linux/of.h
index 72843b7..e2d9b40 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -223,6 +223,10 @@ extern struct device_node *of_find_node_with_property(
extern struct property *of_find_property(const struct device_node *np,
const char *name,
int *lenp);
+extern int of_property_read_u8_array(const struct device_node *np,
+ const char *propname, u8 *out_values, size_t sz);
+extern int of_property_read_u16_array(const struct device_node *np,
+ const char *propname, u16 *out_values, size_t sz);
extern int of_property_read_u32_array(const struct device_node *np,
const char *propname,
u32 *out_values,
@@ -357,6 +361,18 @@ static inline struct device_node *of_find_compatible_node(
return NULL;
}
+static inline int of_property_read_u8_array(const struct device_node *np,
+ const char *propname, u8 *out_values, size_t sz)
+{
+ return -ENOSYS;
+}
+
+static inline int of_property_read_u16_array(const struct device_node *np,
+ const char *propname, u16 *out_values, size_t sz)
+{
+ return -ENOSYS;
+}
+
static inline int of_property_read_u32_array(const struct device_node *np,
const char *propname,
u32 *out_values, size_t sz)
@@ -463,6 +479,20 @@ static inline bool of_property_read_bool(const struct device_node *np,
return prop ? true : false;
}
+static inline int of_property_read_u8(const struct device_node *np,
+ const char *propname,
+ u8 *out_value)
+{
+ return of_property_read_u8_array(np, propname, out_value, 1);
+}
+
+static inline int of_property_read_u16(const struct device_node *np,
+ const char *propname,
+ u16 *out_value)
+{
+ return of_property_read_u16_array(np, propname, out_value, 1);
+}
+
static inline int of_property_read_u32(const struct device_node *np,
const char *propname,
u32 *out_value)
--
1.7.12.rc2.18.g61b472e
On Fri, 2012-10-12 at 23:31 +0530, Viresh Kumar wrote:
> This adds following helper routines:
> - of_property_read_u8_array()
> - of_property_read_u16_array()
> - of_property_read_u8()
> - of_property_read_u16()
>
> First two actually share most of the code with of_property_read_u32_array(), so
> the common part is taken out into a macro, which can be used by all three
> *_array() routines.
>
> Signed-off-by: Viresh Kumar <[email protected]>
> ---
> drivers/of/base.c | 73 +++++++++++++++++++++++++++++++++++++++++++-----------
> include/linux/of.h | 30 ++++++++++++++++++++++
> 2 files changed, 89 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index 38892a9..446fe7f 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -670,6 +670,64 @@ struct device_node *of_find_node_by_phandle(phandle handle)
> }
> EXPORT_SYMBOL(of_find_node_by_phandle);
>
> +#define of_property_read_array(_np, _pname, _out, _sz, _type) \
> + struct property *_prop = of_find_property(_np, _pname, NULL); \
> + const __be32 *_val; \
> + \
> + if (!_prop) \
> + return -EINVAL; \
> + if (!_prop->value) \
> + return -ENODATA; \
> + if ((_sz * sizeof(*_out)) > _prop->length) \
> + return -EOVERFLOW; \
> + \
> + _val = _prop->value; \
> + while (_sz--) \
> + *_out++ = (_type)be32_to_cpup(_val++); \
How about
*_out++ = (typeof(*_out))...
?
> + return 0;
> +
> +/**
> + * of_property_read_u8_array - Find and read an array of u8 from a property.
> + *
> + * @np: device node from which the property value is to be read.
> + * @propname: name of the property to be searched.
> + * @out_value: pointer to return value, modified only if return value is 0.
> + *
> + * Search for a property in a device node and read 8-bit value(s) from
> + * it. Returns 0 on success, -EINVAL if the property does not exist,
> + * -ENODATA if property does not have a value, and -EOVERFLOW if the
> + * property data isn't large enough.
> + *
> + * The out_value is modified only if a valid u8 value can be decoded.
> + */
> +int of_property_read_u8_array(const struct device_node *np,
> + const char *propname, u8 *out_values, size_t sz)
> +{
> + of_property_read_array(np, propname, out_values, sz, u8);
> +}
> +EXPORT_SYMBOL_GPL(of_property_read_u8_array);
> +
> +/**
> + * of_property_read_u16_array - Find and read an array of u16 from a property.
> + *
> + * @np: device node from which the property value is to be read.
> + * @propname: name of the property to be searched.
> + * @out_value: pointer to return value, modified only if return value is 0.
> + *
> + * Search for a property in a device node and read 16-bit value(s) from
> + * it. Returns 0 on success, -EINVAL if the property does not exist,
> + * -ENODATA if property does not have a value, and -EOVERFLOW if the
> + * property data isn't large enough.
> + *
> + * The out_value is modified only if a valid u16 value can be decoded.
> + */
> +int of_property_read_u16_array(const struct device_node *np,
> + const char *propname, u16 *out_values, size_t sz)
> +{
> + of_property_read_array(np, propname, out_values, sz, u16);
> +}
> +EXPORT_SYMBOL_GPL(of_property_read_u16_array);
> +
> /**
> * of_property_read_u32_array - Find and read an array of 32 bit integers
> * from a property.
> @@ -689,20 +747,7 @@ int of_property_read_u32_array(const struct device_node *np,
> const char *propname, u32 *out_values,
> size_t sz)
> {
> - struct property *prop = of_find_property(np, propname, NULL);
> - const __be32 *val;
> -
> - if (!prop)
> - return -EINVAL;
> - if (!prop->value)
> - return -ENODATA;
> - if ((sz * sizeof(*out_values)) > prop->length)
> - return -EOVERFLOW;
> -
> - val = prop->value;
> - while (sz--)
> - *out_values++ = be32_to_cpup(val++);
> - return 0;
> + of_property_read_array(np, propname, out_values, sz, u32);
> }
> EXPORT_SYMBOL_GPL(of_property_read_u32_array);
>
> diff --git a/include/linux/of.h b/include/linux/of.h
> index 72843b7..e2d9b40 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -223,6 +223,10 @@ extern struct device_node *of_find_node_with_property(
> extern struct property *of_find_property(const struct device_node *np,
> const char *name,
> int *lenp);
> +extern int of_property_read_u8_array(const struct device_node *np,
> + const char *propname, u8 *out_values, size_t sz);
> +extern int of_property_read_u16_array(const struct device_node *np,
> + const char *propname, u16 *out_values, size_t sz);
> extern int of_property_read_u32_array(const struct device_node *np,
> const char *propname,
> u32 *out_values,
> @@ -357,6 +361,18 @@ static inline struct device_node *of_find_compatible_node(
> return NULL;
> }
>
> +static inline int of_property_read_u8_array(const struct device_node *np,
> + const char *propname, u8 *out_values, size_t sz)
> +{
> + return -ENOSYS;
> +}
> +
> +static inline int of_property_read_u16_array(const struct device_node *np,
> + const char *propname, u16 *out_values, size_t sz)
> +{
> + return -ENOSYS;
> +}
> +
> static inline int of_property_read_u32_array(const struct device_node *np,
> const char *propname,
> u32 *out_values, size_t sz)
> @@ -463,6 +479,20 @@ static inline bool of_property_read_bool(const struct device_node *np,
> return prop ? true : false;
> }
>
> +static inline int of_property_read_u8(const struct device_node *np,
> + const char *propname,
> + u8 *out_value)
> +{
> + return of_property_read_u8_array(np, propname, out_value, 1);
> +}
> +
> +static inline int of_property_read_u16(const struct device_node *np,
> + const char *propname,
> + u16 *out_value)
> +{
> + return of_property_read_u16_array(np, propname, out_value, 1);
> +}
> +
> static inline int of_property_read_u32(const struct device_node *np,
> const char *propname,
> u32 *out_value)
--
Andy Shevchenko <[email protected]>
Intel Finland Oy
---------------------------------------------------------------------
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This e-mail and any attachments may contain confidential material for
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????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay? ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?
On 15 October 2012 13:26, Shevchenko, Andriy
<[email protected]> wrote:
> On Fri, 2012-10-12 at 23:31 +0530, Viresh Kumar wrote:
>> + while (_sz--) \
>> + *_out++ = (_type)be32_to_cpup(_val++); \
> How about
> *_out++ = (typeof(*_out))...
> ?
:)
diff --git a/drivers/of/base.c b/drivers/of/base.c
index c5a09c2..039e178 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -670,7 +670,7 @@ struct device_node *of_find_node_by_phandle(phandle handle)
}
EXPORT_SYMBOL(of_find_node_by_phandle);
-#define of_property_read_array(_np, _pname, _out, _sz, _type) \
+#define of_property_read_array(_np, _pname, _out, _sz) \
struct property *_prop = of_find_property(_np, _pname, NULL); \
const __be32 *_val; \
\
@@ -683,7 +683,7 @@ EXPORT_SYMBOL(of_find_node_by_phandle);
\
_val = _prop->value; \
while (_sz--) \
- *_out++ = (_type)be32_to_cpup(_val++); \
+ *_out++ = (typeof(*_out))be32_to_cpup(_val++); \
return 0;
/**
@@ -703,7 +703,7 @@ EXPORT_SYMBOL(of_find_node_by_phandle);
int of_property_read_u8_array(const struct device_node *np,
const char *propname, u8 *out_values, size_t sz)
{
- of_property_read_array(np, propname, out_values, sz, u8);
+ of_property_read_array(np, propname, out_values, sz);
}
EXPORT_SYMBOL_GPL(of_property_read_u8_array);
@@ -724,7 +724,7 @@ EXPORT_SYMBOL_GPL(of_property_read_u8_array);
int of_property_read_u16_array(const struct device_node *np,
const char *propname, u16 *out_values, size_t sz)
{
- of_property_read_array(np, propname, out_values, sz, u16);
+ of_property_read_array(np, propname, out_values, sz);
}
EXPORT_SYMBOL_GPL(of_property_read_u16_array);
@@ -747,7 +747,7 @@ int of_property_read_u32_array(const struct device_node *np,
const char *propname, u32 *out_values,
size_t sz)
{
- of_property_read_array(np, propname, out_values, sz, u32);
+ of_property_read_array(np, propname, out_values, sz);
}
EXPORT_SYMBOL_GPL(of_property_read_u32_array);
On 12 October 2012 23:31, Viresh Kumar <[email protected]> wrote:
> This adds following helper routines:
> - of_property_read_u8_array()
> - of_property_read_u16_array()
> - of_property_read_u8()
> - of_property_read_u16()
>
> First two actually share most of the code with of_property_read_u32_array(), so
> the common part is taken out into a macro, which can be used by all three
> *_array() routines.
Hi Rob,
Any comment here?
--
viresh
On 10/25/2012 02:03 AM, Viresh Kumar wrote:
> On 12 October 2012 23:31, Viresh Kumar <[email protected]> wrote:
>> This adds following helper routines:
>> - of_property_read_u8_array()
>> - of_property_read_u16_array()
>> - of_property_read_u8()
>> - of_property_read_u16()
>>
>> First two actually share most of the code with of_property_read_u32_array(), so
>> the common part is taken out into a macro, which can be used by all three
>> *_array() routines.
>
> Hi Rob,
>
> Any comment here?
For some reason, this does not show up on the list either in my mail or
mail list archives, but it is in patchwork. Can you resend it please.
The main question I have is be32_to_cpup() the right thing to do. I
would expect byte arrays to not need endian conversion, but I haven't
looked at how '/bits/ x' data is stored.
Rob
On 25 October 2012 18:49, Rob Herring <[email protected]> wrote:
> For some reason, this does not show up on the list either in my mail or
> mail list archives, but it is in patchwork. Can you resend it please.
Strange. I kept you in --to field. I know people added in cc are
sometimes removed
by the list when they have selected "avoid duplicate mails" option for
their list.
> The main question I have is be32_to_cpup() the right thing to do. I
> would expect byte arrays to not need endian conversion, but I haven't
> looked at how '/bits/ x' data is stored.
The problem i see here is:
The data passed via DT comes as Little Endian in the kernel.
For a little endian system, byte zero will contain the data and so
(u8) val
look to be the correct thing.
For a big endian system, byte 3 will contain data as it is swapped by
be32_to_cpup.
So (u8) val would return value stored by byte 0 instead. ??
Does my logic look correct to you??
--
viresh
On 25 October 2012 19:48, Viresh Kumar <[email protected]> wrote:
> The problem i see here is:
>
> The data passed via DT comes as Little Endian in the kernel.
>
> For a little endian system, byte zero will contain the data and so
> (u8) val
>
> look to be the correct thing.
>
> For a big endian system, byte 3 will contain data as it is swapped by
> be32_to_cpup.
> So (u8) val would return value stored by byte 0 instead. ??
I feel above explanation was wrong. I didn't had a big endian system
to test this but this is what i derived theoretically. Consider following
sequence of commands:
u32 x = 0x01; //This will store off-0: 1, off-3:0 for LE system
// and will store off-0: 0, off-3:1
for BE system
u8 y = (u8) x; // For any architecture type, i.e. big or
little this must store
// 1 in y. This is ANCI C semantic
and should be architecture
// independent.
Which would mean, type cast will give off-0 on LE and off-3 on BE systems. Don't
confuse this with getting values using pointers, as we try to get data
out of specific
locations in those cases.
So, my initial code seems to be doing the right thing. be32_to_cpup()
will move the
LSB to off-3 and that is what we will get during the cast.
I will resend my original code to you.
--
viresh