From: Thierry Reding <treding@xxxxxxxxxx> This function is similar to of_translate_dma_address() but also reads a length in addition to an address from a device tree property. Signed-off-by: Thierry Reding <treding@xxxxxxxxxx> --- drivers/of/address.c | 41 ++++++++++++++++++++++++++++++++++++++ include/linux/of_address.h | 2 ++ 2 files changed, 43 insertions(+) diff --git a/drivers/of/address.c b/drivers/of/address.c index c34ac33b7338..14f137a21b0c 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -626,6 +626,47 @@ u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr) } EXPORT_SYMBOL(of_translate_dma_address); +/** + * of_translate_dma_region - Translate device tree address and size tuple + * @dev: device tree node for which to translate + * @prop: pointer into array of cells + * @start: return value for the start of the DMA range + * @length: return value for the length of the DMA range + * + * Returns a pointer to the cell immediately following the translated DMA region. + */ +const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *prop, + phys_addr_t *start, size_t *length) +{ + struct device_node *parent; + u64 address, size; + int na, ns; + + parent = __of_get_dma_parent(dev); + if (!parent) + return NULL; + + na = of_bus_n_addr_cells(parent); + ns = of_bus_n_size_cells(parent); + + of_node_put(parent); + + address = of_translate_dma_address(dev, prop); + if (address == OF_BAD_ADDR) + return NULL; + + size = of_read_number(prop + na, ns); + + if (start) + *start = address; + + if (length) + *length = size; + + return prop + na + ns; +} +EXPORT_SYMBOL(of_translate_dma_region); + const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no, u64 *size, unsigned int *flags) { diff --git a/include/linux/of_address.h b/include/linux/of_address.h index 265f26eeaf6b..376671594746 100644 --- a/include/linux/of_address.h +++ b/include/linux/of_address.h @@ -38,6 +38,8 @@ struct of_pci_range { /* Translate a DMA address from device space to CPU space */ extern u64 of_translate_dma_address(struct device_node *dev, const __be32 *in_addr); +extern const __be32 *of_translate_dma_region(struct device_node *dev, const __be32 *addr, + phys_addr_t *start, size_t *length); #ifdef CONFIG_OF_ADDRESS extern u64 of_translate_address(struct device_node *np, const __be32 *addr); -- 2.38.1