diff options
| 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 /drivers/of/address.c | |
| parent | 18308c94723e162ed121942335bc186e66820a7a (diff) | |
| download | linux-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>
Diffstat (limited to 'drivers/of/address.c')
| -rw-r--r-- | drivers/of/address.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/of/address.c b/drivers/of/address.c index c54baee87d93..d244b2859aac 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 |