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| author | Santosh Shilimkar <santosh.shilimkar@ti.com> | 2014-04-24 11:30:03 -0400 |
|---|---|---|
| committer | Santosh Shilimkar <santosh.shilimkar@ti.com> | 2014-05-05 18:11:13 -0400 |
| commit | 92ea637edea36e58236e3124f199161da6f5c5de (patch) | |
| tree | 3d448091313a8f872a8e6bb7498c447350d801b8 | |
| parent | 18308c94723e162ed121942335bc186e66820a7a (diff) | |
| download | op-kernel-dev-92ea637edea36e58236e3124f199161da6f5c5de.zip op-kernel-dev-92ea637edea36e58236e3124f199161da6f5c5de.tar.gz | |
of: introduce of_dma_is_coherent() helper
The of_dma_is_coherent() helper parses the given DT device
node to see if the "dma-coherent" property is supported and
returns true or false accordingly.
If the arch is always coherent or always noncoherent, then the default
DMA ops has to be specified accordingly.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Olof Johansson <olof@lixom.net>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
| -rw-r--r-- | drivers/of/address.c | 23 | ||||
| -rw-r--r-- | include/linux/of_address.h | 6 |
2 files changed, 29 insertions, 0 deletions
diff --git a/drivers/of/address.c b/drivers/of/address.c index c54baee..d244b28 100644 --- a/drivers/of/address.c +++ b/drivers/of/address.c @@ -808,3 +808,26 @@ out: return ret; } EXPORT_SYMBOL_GPL(of_dma_get_range); + +/** + * of_dma_is_coherent - Check if device is coherent + * @np: device node + * + * It returns true if "dma-coherent" property was found + * for this device in DT. + */ +bool of_dma_is_coherent(struct device_node *np) +{ + struct device_node *node = of_node_get(np); + + while (node) { + if (of_property_read_bool(node, "dma-coherent")) { + of_node_put(node); + return true; + } + node = of_get_next_parent(node); + } + of_node_put(node); + return false; +} +EXPORT_SYMBOL_GPL(of_dma_is_coherent);
\ No newline at end of file diff --git a/include/linux/of_address.h b/include/linux/of_address.h index 4d7b325..839a352 100644 --- a/include/linux/of_address.h +++ b/include/linux/of_address.h @@ -65,6 +65,7 @@ extern struct of_pci_range *of_pci_range_parser_one( struct of_pci_range *range); extern int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size); +extern bool of_dma_is_coherent(struct device_node *np); #else /* CONFIG_OF_ADDRESS */ static inline struct device_node *of_find_matching_node_by_address( struct device_node *from, @@ -98,6 +99,11 @@ static inline int of_dma_get_range(struct device_node *np, u64 *dma_addr, { return -ENODEV; } + +static inline bool of_dma_is_coherent(struct device_node *np) +{ + return false; +} #endif /* CONFIG_OF_ADDRESS */ #ifdef CONFIG_OF |
