Commit e5e55864 authored by Suthikulpanit, Suravee's avatar Suthikulpanit, Suravee Committed by Rafael J. Wysocki
Browse files

device property: Adding DMA Attribute APIs for Generic Devices 



The function device_dma_is_coherent() does not sufficiently
communicate device DMA attributes. Instead, this patch introduces
device_get_dma_attr(), which returns enum dev_dma_attr.
It replaces the acpi_check_dma(), which will be removed in
subsequent patch.

This also provides a convenient function, device_dma_supported(),
to check DMA support of the specified device.

Signed-off-by: default avatarSuravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarHanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent b84f196d

drivers/base/property.c

+29 −0
Original line number Diff line number Diff line
@@ -611,6 +611,35 @@ bool device_dma_is_coherent(struct device *dev) 
}

EXPORT_SYMBOL_GPL(device_dma_is_coherent);



bool device_dma_supported(struct device *dev)

{

	/* For DT, this is always supported.

	 * For ACPI, this depends on CCA, which

	 * is determined by the acpi_dma_supported().

	 */

	if (IS_ENABLED(CONFIG_OF) && dev->of_node)

		return true;



	return acpi_dma_supported(ACPI_COMPANION(dev));

}

EXPORT_SYMBOL_GPL(device_dma_supported);



enum dev_dma_attr device_get_dma_attr(struct device *dev)

{

	enum dev_dma_attr attr = DEV_DMA_NOT_SUPPORTED;



	if (IS_ENABLED(CONFIG_OF) && dev->of_node) {

		if (of_dma_is_coherent(dev->of_node))

			attr = DEV_DMA_COHERENT;

		else

			attr = DEV_DMA_NON_COHERENT;

	} else

		attr = acpi_get_dma_attr(ACPI_COMPANION(dev));



	return attr;

}

EXPORT_SYMBOL_GPL(device_get_dma_attr);



/**

 * device_get_phy_mode - Get phy mode for given device

 * @dev:	Pointer to the given device

include/linux/property.h

+4 −0
Original line number Diff line number Diff line
@@ -176,6 +176,10 @@ void device_add_property_set(struct device *dev, struct property_set *pset); 


bool device_dma_is_coherent(struct device *dev);



bool device_dma_supported(struct device *dev);



enum dev_dma_attr device_get_dma_attr(struct device *dev);



int device_get_phy_mode(struct device *dev);



void *device_get_mac_address(struct device *dev, char *addr, int alen);

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