On Tuesday, November 04, 2014 03:51:12 PM Grant Likely wrote: > On Tue, 21 Oct 2014 23:15:50 +0200 > , "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> > wrote: > > From: "Rafael J. Wysocki" <rafael.j.wysocki@xxxxxxxxx> > > > > Add a uniform interface by which device drivers can request device > > properties from the platform firmware by providing a property name > > and the corresponding data type. The purpose of it is to help to > > write portable code that won't depend on any particular platform > > firmware interface. > > > > The following general helper functions are added: > > > > device_property_present() > > device_property_read_u8() > > device_property_read_u16() > > device_property_read_u32() > > device_property_read_u64() > > device_property_read_string() > > device_property_read_u8_array() > > device_property_read_u16_array() > > device_property_read_u32_array() > > device_property_read_u64_array() > > device_property_read_string_array() > > > > The first one allows the caller to check if the given property is > > present. The next 5 of them allow single-valued properties of > > various types to be retrieved in a uniform way. The remaining 5 are > > for reading properties with multiple values (arrays of either numbers > > or strings). > > > > The interface covers both ACPI and Device Trees. > > > > This change set includes material from Mika Westerberg and Aaron Lu. > > > > Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx> > > Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> > > Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> > > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > --- > > > > Changes from v5: > > - acpi_dev_prop_read() can now handle both list (package) and single-value > > properties (the latter are tried first for the last argument equal to 1). > > - There is a new macro to generate the bodies of device_property_read_u*_array(). > > - device_property_read_u*() are implemented using device_property_read_u*_array(). > > - device_property_read_bool() is a new static inline wrapper around > > device_property_present(). > > > > --- > > drivers/acpi/property.c | 178 +++++++++++++++++++++++++++++++++++ > > drivers/base/Makefile | 2 > > drivers/base/property.c | 233 +++++++++++++++++++++++++++++++++++++++++++++++ > > drivers/of/base.c | 106 ++++++++++++++++++--- > > include/linux/acpi.h | 32 ++++++ > > include/linux/of.h | 22 ++++ > > include/linux/property.h | 53 ++++++++++ > > 7 files changed, 609 insertions(+), 17 deletions(-) > > create mode 100644 drivers/base/property.c > > create mode 100644 include/linux/property.h > > > > Index: linux-pm/include/linux/property.h > > =================================================================== > > --- /dev/null > > +++ linux-pm/include/linux/property.h > > @@ -0,0 +1,53 @@ > > +/* > > + * property.h - Unified device property interface. > > + * > > + * Copyright (C) 2014, Intel Corporation > > + * Authors: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > > + * Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> > > + * > > + * This program is free software; you can redistribute it and/or modify > > + * it under the terms of the GNU General Public License version 2 as > > + * published by the Free Software Foundation. > > + */ > > + > > +#ifndef _LINUX_PROPERTY_H_ > > +#define _LINUX_PROPERTY_H_ > > + > > +#include <linux/types.h> > > + > > +struct device; > > + > > +enum dev_prop_type { > > + DEV_PROP_U8, > > + DEV_PROP_U16, > > + DEV_PROP_U32, > > + DEV_PROP_U64, > > + DEV_PROP_STRING, > > + DEV_PROP_MAX, > > +}; > > + > > +bool device_property_present(struct device *dev, const char *propname); > > +int device_property_read_u8_array(struct device *dev, const char *propname, > > + u8 *val, size_t nval); > > +int device_property_read_u16_array(struct device *dev, const char *propname, > > + u16 *val, size_t nval); > > +int device_property_read_u32_array(struct device *dev, const char *propname, > > + u32 *val, size_t nval); > > +int device_property_read_u64_array(struct device *dev, const char *propname, > > + u64 *val, size_t nval); > > +int device_property_read_string_array(struct device *dev, const char *propname, > > + char **val, size_t nval); > > I'm not sure if I asked this elsewhere. Can 'val' be made a const char **? You did. :-) I have a new version of the patch with that change. I'll send it in a while. Rafael -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html