From e5e558644bbb23cad03c586703331b8bcd9e0e6c Mon Sep 17 00:00:00 2001 From: "Suthikulpanit, Suravee" Date: Wed, 28 Oct 2015 15:50:49 -0700 Subject: [PATCH] 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: Suravee Suthikulpanit Acked-by: Bjorn Helgaas Reviewed-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki --- drivers/base/property.c | 29 +++++++++++++++++++++++++++++ include/linux/property.h | 4 ++++ 2 files changed, 33 insertions(+) diff --git a/drivers/base/property.c b/drivers/base/property.c index de40623bbd8a..05d57a2afa05 100644 --- a/drivers/base/property.c +++ b/drivers/base/property.c @@ -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 diff --git a/include/linux/property.h b/include/linux/property.h index 8eecf200bae5..7200490b7e6f 100644 --- a/include/linux/property.h +++ b/include/linux/property.h @@ -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); -- 2.39.5