diff mbox

[v3,3/7] of: introduce of_dma_is_coherent() helper

Message ID 1398353407-2345-4-git-send-email-santosh.shilimkar@ti.com
State New
Headers show

Commit Message

Santosh Shilimkar April 24, 2014, 3:30 p.m. UTC
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: Rob Herring <robh+dt@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
---
 drivers/of/platform.c       |   23 +++++++++++++++++++++++
 include/linux/of_platform.h |    6 ++++++
 2 files changed, 29 insertions(+)

Comments

Rob Herring May 2, 2014, 12:56 a.m. UTC | #1
On Thu, Apr 24, 2014 at 10:30 AM, Santosh Shilimkar
<santosh.shilimkar@ti.com> wrote:
> 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: Rob Herring <robh+dt@kernel.org>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
> ---
>  drivers/of/platform.c       |   23 +++++++++++++++++++++++
>  include/linux/of_platform.h |    6 ++++++

I thought I said this already, but this does not belong in these files
as the function does not deal with platform devices. Probably
address.c/of_address.h would be the best place.

Rob

>  2 files changed, 29 insertions(+)
>
> diff --git a/drivers/of/platform.c b/drivers/of/platform.c
> index 404d1da..48de98f 100644
> --- a/drivers/of/platform.c
> +++ b/drivers/of/platform.c
> @@ -485,4 +485,27 @@ int of_platform_populate(struct device_node *root,
>         return rc;
>  }
>  EXPORT_SYMBOL_GPL(of_platform_populate);
> +
> +/**
> + * 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);
>  #endif /* CONFIG_OF_ADDRESS */
> diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h
> index 05cb4a9..b9a3cb2 100644
> --- a/include/linux/of_platform.h
> +++ b/include/linux/of_platform.h
> @@ -72,6 +72,7 @@ extern int of_platform_populate(struct device_node *root,
>                                 const struct of_device_id *matches,
>                                 const struct of_dev_auxdata *lookup,
>                                 struct device *parent);
> +extern bool of_dma_is_coherent(struct device_node *np);
>  #else
>  static inline int of_platform_populate(struct device_node *root,
>                                         const struct of_device_id *matches,
> @@ -80,6 +81,11 @@ static inline int of_platform_populate(struct device_node *root,
>  {
>         return -ENODEV;
>  }
> +
> +static inline bool of_dma_is_coherent(struct device_node *np)
> +{
> +       return false;
> +}
>  #endif
>
>  #endif /* _LINUX_OF_PLATFORM_H */
> --
> 1.7.9.5
>
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diff mbox

Patch

diff --git a/drivers/of/platform.c b/drivers/of/platform.c
index 404d1da..48de98f 100644
--- a/drivers/of/platform.c
+++ b/drivers/of/platform.c
@@ -485,4 +485,27 @@  int of_platform_populate(struct device_node *root,
 	return rc;
 }
 EXPORT_SYMBOL_GPL(of_platform_populate);
+
+/**
+ * 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);
 #endif /* CONFIG_OF_ADDRESS */
diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h
index 05cb4a9..b9a3cb2 100644
--- a/include/linux/of_platform.h
+++ b/include/linux/of_platform.h
@@ -72,6 +72,7 @@  extern int of_platform_populate(struct device_node *root,
 				const struct of_device_id *matches,
 				const struct of_dev_auxdata *lookup,
 				struct device *parent);
+extern bool of_dma_is_coherent(struct device_node *np);
 #else
 static inline int of_platform_populate(struct device_node *root,
 					const struct of_device_id *matches,
@@ -80,6 +81,11 @@  static inline int of_platform_populate(struct device_node *root,
 {
 	return -ENODEV;
 }
+
+static inline bool of_dma_is_coherent(struct device_node *np)
+{
+	return false;
+}
 #endif
 
 #endif	/* _LINUX_OF_PLATFORM_H */