Commit 826a5d8c authored by Andy Shevchenko's avatar Andy Shevchenko Committed by Greg Kroah-Hartman
Browse files

device property: Implement device_is_big_endian() 



Some users want to use the struct device pointer to see if the
device is big endian in terms of Open Firmware specifications,
i.e. if it has a "big-endian" property, or if the kernel was
compiled for BE *and* the device has a "native-endian" property.

Provide inline helper for the users.

Signed-off-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20231025184259.250588-2-andriy.shevchenko@linux.intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 2cc14f52

include/linux/property.h

+26 −0
Original line number Diff line number Diff line
@@ -80,12 +80,38 @@ int fwnode_property_match_string(const struct fwnode_handle *fwnode, 


bool fwnode_device_is_available(const struct fwnode_handle *fwnode);



static inline bool fwnode_device_is_big_endian(const struct fwnode_handle *fwnode)

{

	if (fwnode_property_present(fwnode, "big-endian"))

		return true;

	if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&

	    fwnode_property_present(fwnode, "native-endian"))

		return true;

	return false;

}



static inline

bool fwnode_device_is_compatible(const struct fwnode_handle *fwnode, const char *compat)

{

	return fwnode_property_match_string(fwnode, "compatible", compat) >= 0;

}



/**

 * device_is_big_endian - check if a device has BE registers

 * @dev: Pointer to the struct device

 *

 * Returns: true if the device has a "big-endian" property, or if the kernel

 * was compiled for BE *and* the device has a "native-endian" property.

 * Returns false otherwise.

 *

 * Callers would nominally use ioread32be/iowrite32be if

 * device_is_big_endian() == true, or readl/writel otherwise.

 */

static inline bool device_is_big_endian(const struct device *dev)

{

	return fwnode_device_is_big_endian(dev_fwnode(dev));

}



/**

 * device_is_compatible - match 'compatible' property of the device with a given string

 * @dev: Pointer to the struct device