From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Glass Subject: [PATCH v2 03/19] fdt: Add function to look up a phandle's register address Date: Wed, 13 Jun 2012 09:19:39 -0700 Message-ID: <1339604395-6621-4-git-send-email-sjg@chromium.org> References: <1339604395-6621-1-git-send-email-sjg@chromium.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1339604395-6621-1-git-send-email-sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: "devicetree-discuss" To: U-Boot Mailing List Cc: Devicetree Discuss , Tom Warren , Jerry Van Baren List-Id: devicetree@vger.kernel.org This is a commonly-used requirement, so add a function to support it easily. Signed-off-by: Simon Glass --- include/fdtdec.h | 13 +++++++++++++ lib/fdtdec.c | 11 +++++++++++ 2 files changed, 24 insertions(+), 0 deletions(-) diff --git a/include/fdtdec.h b/include/fdtdec.h index fab577e..d7bef6c 100644 --- a/include/fdtdec.h +++ b/include/fdtdec.h @@ -276,6 +276,19 @@ const char *fdtdec_get_compatible(enum fdt_compat_id id); int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name); /** + * Look up a phandle and follow it to its node. Then return the register + * address of that node as a pointer. This can be used to access the + * peripheral directly. + * + * @param blob FDT blob + * @param node node to examine + * @param prop_name name of property to find + * @return pointer to node's register address + */ +void *fdtdec_lookup_phandle_reg(const void *blob, int node, + const char *prop_name); + +/** * Look up a property in a node and return its contents in an integer * array of given length. The property must have at least enough data for * the array (4*count bytes). It may have more, but this will be ignored. diff --git a/lib/fdtdec.c b/lib/fdtdec.c index 61056f1..8185d8f 100644 --- a/lib/fdtdec.c +++ b/lib/fdtdec.c @@ -347,6 +347,17 @@ int fdtdec_lookup_phandle(const void *blob, int node, const char *prop_name) return lookup; } +void *fdtdec_lookup_phandle_reg(const void *blob, int node, + const char *prop_name) +{ + int lookup; + + lookup = fdtdec_lookup_phandle(blob, node, prop_name); + if (lookup < 0) + return NULL; + return (void *)fdtdec_get_addr(blob, lookup, "reg"); +} + /** * Look up a property in a node and check that it has a minimum length. * -- 1.7.7.3