From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ns.lynxeye.de ([87.118.118.114] helo=lynxeye.de) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1UtOqd-0002Z4-Gh for barebox@lists.infradead.org; Sun, 30 Jun 2013 21:07:55 +0000 Received: from tellur.localdomain (p54832945.dip0.t-ipconnect.de [84.131.41.69]) by lynxeye.de (Postfix) with ESMTPA id 0654918B424F for ; Sun, 30 Jun 2013 23:06:51 +0200 (CEST) From: Lucas Stach Date: Sun, 30 Jun 2013 23:08:43 +0200 Message-Id: <1372626529-23443-1-git-send-email-dev@lynxeye.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH v2 1/7] clk: add clock lookup from devicetree To: barebox@lists.infradead.org Taken from the Linuxkernel with some small adjustments for barebox. Signed-off-by: Lucas Stach --- v2: introduce new Kconfig symbol COMMON_CLK_OF_PROVIDER to avoid increased binary size for systems not using OF clk. --- drivers/clk/Kconfig | 5 +++ drivers/clk/clk.c | 97 ++++++++++++++++++++++++++++++++++++++++++++++++++++ drivers/clk/clkdev.c | 74 +++++++++++++++++++++++++++++++++++++++ include/linux/clk.h | 33 ++++++++++++++++++ 4 files changed, 209 insertions(+) diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig index 4589128..a00e539 100644 --- a/drivers/clk/Kconfig +++ b/drivers/clk/Kconfig @@ -4,3 +4,8 @@ config CLKDEV_LOOKUP config COMMON_CLK bool + +config COMMON_CLK_OF_PROVIDER + bool + help + Clock driver provides OF-Tree based clock lookup. diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 690a0c6..7ec3d93 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -16,6 +16,7 @@ */ #include #include +#include #include #include @@ -253,6 +254,102 @@ int clk_is_enabled_always(struct clk *clk) return 1; } +#if defined(CONFIG_OFTREE) && defined(CONFIG_COMMON_CLK_OF_PROVIDER) +/** + * struct of_clk_provider - Clock provider registration structure + * @link: Entry in global list of clock providers + * @node: Pointer to device tree node of clock provider + * @get: Get clock callback. Returns NULL or a struct clk for the + * given clock specifier + * @data: context pointer to be passed into @get callback + */ +struct of_clk_provider { + struct list_head link; + + struct device_node *node; + struct clk *(*get)(struct of_phandle_args *clkspec, void *data); + void *data; +}; + +static LIST_HEAD(of_clk_providers); + +struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data) +{ + struct clk_onecell_data *clk_data = data; + unsigned int idx = clkspec->args[0]; + + if (idx >= clk_data->clk_num) { + pr_err("%s: invalid clock index %d\n", __func__, idx); + return ERR_PTR(-EINVAL); + } + + return clk_data->clks[idx]; +} +EXPORT_SYMBOL_GPL(of_clk_src_onecell_get); + +/** + * of_clk_add_provider() - Register a clock provider for a node + * @np: Device node pointer associated with clock provider + * @clk_src_get: callback for decoding clock + * @data: context pointer for @clk_src_get callback. + */ +int of_clk_add_provider(struct device_node *np, + struct clk *(*clk_src_get)(struct of_phandle_args *clkspec, + void *data), + void *data) +{ + struct of_clk_provider *cp; + + cp = kzalloc(sizeof(struct of_clk_provider), GFP_KERNEL); + if (!cp) + return -ENOMEM; + + cp->node = np; + cp->data = data; + cp->get = clk_src_get; + + list_add(&cp->link, &of_clk_providers); + pr_debug("Added clock from %s\n", np->full_name); + + return 0; +} +EXPORT_SYMBOL_GPL(of_clk_add_provider); + +/** + * of_clk_del_provider() - Remove a previously registered clock provider + * @np: Device node pointer associated with clock provider + */ +void of_clk_del_provider(struct device_node *np) +{ + struct of_clk_provider *cp; + + list_for_each_entry(cp, &of_clk_providers, link) { + if (cp->node == np) { + list_del(&cp->link); + kfree(cp); + break; + } + } +} +EXPORT_SYMBOL_GPL(of_clk_del_provider); + +struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec) +{ + struct of_clk_provider *provider; + struct clk *clk = ERR_PTR(-ENOENT); + + /* Check if we have such a provider in our array */ + list_for_each_entry(provider, &of_clk_providers, link) { + if (provider->node == clkspec->np) + clk = provider->get(clkspec, provider->data); + if (!IS_ERR(clk)) + break; + } + + return clk; +} +#endif + static void dump_one(struct clk *clk, int verbose, int indent) { struct clk *c; diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c index 256927e..66cd832 100644 --- a/drivers/clk/clkdev.c +++ b/drivers/clk/clkdev.c @@ -19,10 +19,80 @@ #include #include #include +#include #include static LIST_HEAD(clocks); +#if defined(CONFIG_OFTREE) && defined(CONFIG_COMMON_CLK_OF_PROVIDER) +struct clk *of_clk_get(struct device_node *np, int index) +{ + struct of_phandle_args clkspec; + struct clk *clk; + int rc; + + if (index < 0) + return ERR_PTR(-EINVAL); + + rc = of_parse_phandle_with_args(np, "clocks", "#clock-cells", index, + &clkspec); + if (rc) + return ERR_PTR(rc); + + clk = of_clk_get_from_provider(&clkspec); + return clk; +} +EXPORT_SYMBOL(of_clk_get); + +/** + * of_clk_get_by_name() - Parse and lookup a clock referenced by a device node + * @np: pointer to clock consumer node + * @name: name of consumer's clock input, or NULL for the first clock reference + * + * This function parses the clocks and clock-names properties, + * and uses them to look up the struct clk from the registered list of clock + * providers. + */ +struct clk *of_clk_get_by_name(struct device_node *np, const char *name) +{ + struct clk *clk = ERR_PTR(-ENOENT); + + /* Walk up the tree of devices looking for a clock that matches */ + while (np) { + int index = 0; + + /* + * For named clocks, first look up the name in the + * "clock-names" property. If it cannot be found, then + * index will be an error code, and of_clk_get() will fail. + */ + if (name) + index = of_property_match_string(np, "clock-names", + name); + clk = of_clk_get(np, index); + if (!IS_ERR(clk)) + break; + else if (name && index >= 0) { + pr_err("ERROR: could not get clock %s:%s(%i)\n", + np->full_name, name ? name : "", index); + return clk; + } + + /* + * No matching clock found on this node. If the parent node + * has a "clock-ranges" property, then we can try one of its + * clocks. + */ + np = np->parent; + if (np && !of_get_property(np, "clock-ranges", NULL)) + break; + } + + return clk; +} +EXPORT_SYMBOL(of_clk_get_by_name); +#endif + /* * Find the correct struct clk for the device and connection ID. * We do slightly fuzzy matching here: @@ -109,6 +179,10 @@ struct clk *clk_get(struct device_d *dev, const char *con_id) if (!IS_ERR(clk)) return clk; + clk = of_clk_get_by_name(dev->device_node, con_id); + if (!IS_ERR(clk)) + return clk; + return clk_get_sys(dev_id, con_id); } EXPORT_SYMBOL(clk_get); diff --git a/include/linux/clk.h b/include/linux/clk.h index 38832ba..1cb661e 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -11,6 +11,8 @@ #ifndef __LINUX_CLK_H #define __LINUX_CLK_H +#include + struct device_d; /* @@ -228,4 +230,35 @@ void clk_dump(int verbose); #endif +struct device_node; +struct of_phandle_args; + +#if defined(CONFIG_OFTREE) && defined(CONFIG_COMMON_CLK_OF_PROVIDER) +int of_clk_add_provider(struct device_node *np, + struct clk *(*clk_src_get)(struct of_phandle_args *args, + void *data), + void *data); +void of_clk_del_provider(struct device_node *np); + +struct clk_onecell_data { + struct clk **clks; + unsigned int clk_num; +}; +struct clk *of_clk_src_onecell_get(struct of_phandle_args *clkspec, void *data); + +struct clk *of_clk_get(struct device_node *np, int index); +struct clk *of_clk_get_by_name(struct device_node *np, const char *name); +struct clk *of_clk_get_from_provider(struct of_phandle_args *clkspec); +#else +static inline struct clk *of_clk_get(struct device_node *np, int index) +{ + return ERR_PTR(-ENOENT); +} +static inline struct clk *of_clk_get_by_name(struct device_node *np, + const char *name) +{ + return ERR_PTR(-ENOENT); +} +#endif + #endif -- 1.8.3.1 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox