From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933173AbaFQPdM (ORCPT ); Tue, 17 Jun 2014 11:33:12 -0400 Received: from mailout2.w1.samsung.com ([210.118.77.12]:63655 "EHLO mailout2.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756032AbaFQPdK (ORCPT ); Tue, 17 Jun 2014 11:33:10 -0400 X-AuditID: cbfec7f4-b7fac6d000006cfe-60-53a05fb459b8 From: Tomasz Figa To: linux-samsung-soc@vger.kernel.org Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Kukjin Kim , Russell King - ARM Linux , Pankaj Dubey , chow.kim@samsung.com, vikas.sajjan@samsung.com, joshi@samsung.com, Samuel Ortiz , Lee Jones , Tomasz Figa Subject: [PATCH RFC] mfd: syscon: Decouple syscon interface from syscon devices Date: Tue, 17 Jun 2014 17:32:44 +0200 Message-id: <1403019164-12514-1-git-send-email-t.figa@samsung.com> X-Mailer: git-send-email 1.9.3 In-reply-to: <53A05E2D.6020702@samsung.com> References: <53A05E2D.6020702@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprILMWRmVeSWpSXmKPExsVy+t/xK7pb4hcEG0yfwG6xbNJdNovvu76w W/QuuMpmcf/rUUaLTY+vsVpc3jWHzWLG+X1MFrcv81os2gpUcbqb1WL9jNcsFjefbWdy4PFo ae5h87hzbQ+bx7yTgR6bl9R79G1ZxejxeZNcAFsUl01Kak5mWWqRvl0CV8bviddYChqMKpoP HWJrYFys2cXIySEhYCIxde9qNghbTOLCvfVANheHkMBSRomWQz3MEE4fk8TfKbNZQKrYBNQk Pjc8AusQEVCV+Ny2gB2kiFngP5PErUMLWUESwgL+Ev93/wYrYgEqun/oClicV8BJ4uPLq1Dr 5CR6t71hBrE5BbQlvh5fzwRiCwloSTz78o9xAiPvAkaGVYyiqaXJBcVJ6bmGesWJucWleel6 yfm5mxghwfhlB+PiY1aHGAU4GJV4eCMuzQ8WYk0sK67MPcQowcGsJMJbIr4gWIg3JbGyKrUo P76oNCe1+BAjEwenVAOjwiRHDZOVDs/vsMbaxTa3my002Zu3nufmtmm1CodLRd7u2eskzi+7 Imffce5i15zN6ibxi3MTQ05J3zjzSP/emkS1yDN1pyKnTVl9vjZk6TIlgVzZsyq2npGetqdc HcpcZ7WaKvyINFVtDtN63JE389vHhXMnJDiZHLvOO881yy7YtuzmEgUlluKMREMt5qLiRABF oez+JAIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently a syscon entity can be only registered directly through a platform device that binds to a dedicated driver. However in certain use cases it is desirable to make a device used with another driver a syscon interface provider. For example, certain SoCs (e.g. Exynos) contain system controller blocks which perform various functions such as power domain control, CPU power management, low power mode control, but in addition contain certain IP integration glue, such as various signal masks, coprocessor power control, etc. In such case, there is a need to have a dedicated driver for such system controller but also share registers with other drivers. The latter is where the syscon interface is helpful. This patch decouples syscon object from syscon driver, so that it can be registered from any driver in addition to the original "syscon" platform driver. Signed-off-by: Tomasz Figa --- drivers/mfd/syscon.c | 102 +++++++++++++++++++++++++++++---------------- include/linux/mfd/syscon.h | 9 ++++ 2 files changed, 75 insertions(+), 36 deletions(-) diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c index ca15878..11baaae 100644 --- a/drivers/mfd/syscon.c +++ b/drivers/mfd/syscon.c @@ -14,6 +14,7 @@ #include #include +#include #include #include #include @@ -23,30 +24,28 @@ #include #include -static struct platform_driver syscon_driver; +static DEFINE_SPINLOCK(syscon_list_slock); +static LIST_HEAD(syscon_list); struct syscon { struct regmap *regmap; + struct device *dev; + struct list_head list; }; -static int syscon_match_node(struct device *dev, void *data) -{ - struct device_node *dn = data; - - return (dev->of_node == dn) ? 1 : 0; -} - struct regmap *syscon_node_to_regmap(struct device_node *np) { - struct syscon *syscon; - struct device *dev; + struct syscon *entry, *syscon = ERR_PTR(-EPROBE_DEFER); + + spin_lock(&syscon_list_slock); - dev = driver_find_device(&syscon_driver.driver, NULL, np, - syscon_match_node); - if (!dev) - return ERR_PTR(-EPROBE_DEFER); + list_for_each_entry(entry, &syscon_list, list) + if (entry->dev->of_node == np) { + syscon = entry; + break; + } - syscon = dev_get_drvdata(dev); + spin_unlock(&syscon_list_slock); return syscon->regmap; } @@ -68,22 +67,19 @@ struct regmap *syscon_regmap_lookup_by_compatible(const char *s) } EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible); -static int syscon_match_pdevname(struct device *dev, void *data) -{ - return !strcmp(dev_name(dev), (const char *)data); -} - struct regmap *syscon_regmap_lookup_by_pdevname(const char *s) { - struct device *dev; - struct syscon *syscon; + struct syscon *entry, *syscon = ERR_PTR(-EPROBE_DEFER); + + spin_lock(&syscon_list_slock); - dev = driver_find_device(&syscon_driver.driver, NULL, (void *)s, - syscon_match_pdevname); - if (!dev) - return ERR_PTR(-EPROBE_DEFER); + list_for_each_entry(entry, &syscon_list, list) + if (!strcmp(dev_name(entry->dev), s)) { + syscon = entry; + break; + } - syscon = dev_get_drvdata(dev); + spin_unlock(&syscon_list_slock); return syscon->regmap; } @@ -121,17 +117,49 @@ static struct regmap_config syscon_regmap_config = { .reg_stride = 4, }; +static void devm_syscon_unregister(struct device *dev, void *res) +{ + struct syscon *syscon = *(struct syscon **)res; + + spin_lock(&syscon_list_slock); + list_del(&syscon->list); + spin_unlock(&syscon_list_slock); +} + +int devm_syscon_register(struct device *dev, struct regmap *regmap) +{ + struct syscon **ptr, *syscon; + + syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL); + if (!syscon) + return -ENOMEM; + + syscon->regmap = regmap; + syscon->dev = dev; + + ptr = devres_alloc(devm_syscon_unregister, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + spin_lock(&syscon_list_slock); + list_add_tail(&syscon->list, &syscon_list); + spin_unlock(&syscon_list_slock); + + *ptr = syscon; + devres_add(dev, ptr); + + return 0; +} +EXPORT_SYMBOL_GPL(devm_syscon_register); + static int syscon_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct syscon_platform_data *pdata = dev_get_platdata(dev); - struct syscon *syscon; + struct regmap *regmap; struct resource *res; void __iomem *base; - - syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL); - if (!syscon) - return -ENOMEM; + int ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) @@ -144,14 +172,16 @@ static int syscon_probe(struct platform_device *pdev) syscon_regmap_config.max_register = res->end - res->start - 3; if (pdata) syscon_regmap_config.name = pdata->label; - syscon->regmap = devm_regmap_init_mmio(dev, base, + regmap = devm_regmap_init_mmio(dev, base, &syscon_regmap_config); - if (IS_ERR(syscon->regmap)) { + if (IS_ERR(regmap)) { dev_err(dev, "regmap init failed\n"); - return PTR_ERR(syscon->regmap); + return PTR_ERR(regmap); } - platform_set_drvdata(pdev, syscon); + ret = devm_syscon_register(dev, regmap); + if (ret) + return ret; dev_dbg(dev, "regmap %pR registered\n", res); diff --git a/include/linux/mfd/syscon.h b/include/linux/mfd/syscon.h index 75e543b..6a1cadf 100644 --- a/include/linux/mfd/syscon.h +++ b/include/linux/mfd/syscon.h @@ -18,8 +18,11 @@ #include struct device_node; +struct regmap; #ifdef CONFIG_MFD_SYSCON +extern int devm_syscon_register(struct device *dev, struct regmap *regmap); + extern struct regmap *syscon_node_to_regmap(struct device_node *np); extern struct regmap *syscon_regmap_lookup_by_compatible(const char *s); extern struct regmap *syscon_regmap_lookup_by_pdevname(const char *s); @@ -27,6 +30,12 @@ extern struct regmap *syscon_regmap_lookup_by_phandle( struct device_node *np, const char *property); #else +static inline int devm_syscon_register(struct device *dev, + struct regmap *regmap) +{ + return -ENOSYS; +} + static inline struct regmap *syscon_node_to_regmap(struct device_node *np) { return ERR_PTR(-ENOSYS); -- 1.9.3 From mboxrd@z Thu Jan 1 00:00:00 1970 From: t.figa@samsung.com (Tomasz Figa) Date: Tue, 17 Jun 2014 17:32:44 +0200 Subject: [PATCH RFC] mfd: syscon: Decouple syscon interface from syscon devices In-Reply-To: <53A05E2D.6020702@samsung.com> References: <53A05E2D.6020702@samsung.com> Message-ID: <1403019164-12514-1-git-send-email-t.figa@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Currently a syscon entity can be only registered directly through a platform device that binds to a dedicated driver. However in certain use cases it is desirable to make a device used with another driver a syscon interface provider. For example, certain SoCs (e.g. Exynos) contain system controller blocks which perform various functions such as power domain control, CPU power management, low power mode control, but in addition contain certain IP integration glue, such as various signal masks, coprocessor power control, etc. In such case, there is a need to have a dedicated driver for such system controller but also share registers with other drivers. The latter is where the syscon interface is helpful. This patch decouples syscon object from syscon driver, so that it can be registered from any driver in addition to the original "syscon" platform driver. Signed-off-by: Tomasz Figa --- drivers/mfd/syscon.c | 102 +++++++++++++++++++++++++++++---------------- include/linux/mfd/syscon.h | 9 ++++ 2 files changed, 75 insertions(+), 36 deletions(-) diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c index ca15878..11baaae 100644 --- a/drivers/mfd/syscon.c +++ b/drivers/mfd/syscon.c @@ -14,6 +14,7 @@ #include #include +#include #include #include #include @@ -23,30 +24,28 @@ #include #include -static struct platform_driver syscon_driver; +static DEFINE_SPINLOCK(syscon_list_slock); +static LIST_HEAD(syscon_list); struct syscon { struct regmap *regmap; + struct device *dev; + struct list_head list; }; -static int syscon_match_node(struct device *dev, void *data) -{ - struct device_node *dn = data; - - return (dev->of_node == dn) ? 1 : 0; -} - struct regmap *syscon_node_to_regmap(struct device_node *np) { - struct syscon *syscon; - struct device *dev; + struct syscon *entry, *syscon = ERR_PTR(-EPROBE_DEFER); + + spin_lock(&syscon_list_slock); - dev = driver_find_device(&syscon_driver.driver, NULL, np, - syscon_match_node); - if (!dev) - return ERR_PTR(-EPROBE_DEFER); + list_for_each_entry(entry, &syscon_list, list) + if (entry->dev->of_node == np) { + syscon = entry; + break; + } - syscon = dev_get_drvdata(dev); + spin_unlock(&syscon_list_slock); return syscon->regmap; } @@ -68,22 +67,19 @@ struct regmap *syscon_regmap_lookup_by_compatible(const char *s) } EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible); -static int syscon_match_pdevname(struct device *dev, void *data) -{ - return !strcmp(dev_name(dev), (const char *)data); -} - struct regmap *syscon_regmap_lookup_by_pdevname(const char *s) { - struct device *dev; - struct syscon *syscon; + struct syscon *entry, *syscon = ERR_PTR(-EPROBE_DEFER); + + spin_lock(&syscon_list_slock); - dev = driver_find_device(&syscon_driver.driver, NULL, (void *)s, - syscon_match_pdevname); - if (!dev) - return ERR_PTR(-EPROBE_DEFER); + list_for_each_entry(entry, &syscon_list, list) + if (!strcmp(dev_name(entry->dev), s)) { + syscon = entry; + break; + } - syscon = dev_get_drvdata(dev); + spin_unlock(&syscon_list_slock); return syscon->regmap; } @@ -121,17 +117,49 @@ static struct regmap_config syscon_regmap_config = { .reg_stride = 4, }; +static void devm_syscon_unregister(struct device *dev, void *res) +{ + struct syscon *syscon = *(struct syscon **)res; + + spin_lock(&syscon_list_slock); + list_del(&syscon->list); + spin_unlock(&syscon_list_slock); +} + +int devm_syscon_register(struct device *dev, struct regmap *regmap) +{ + struct syscon **ptr, *syscon; + + syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL); + if (!syscon) + return -ENOMEM; + + syscon->regmap = regmap; + syscon->dev = dev; + + ptr = devres_alloc(devm_syscon_unregister, sizeof(*ptr), GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + spin_lock(&syscon_list_slock); + list_add_tail(&syscon->list, &syscon_list); + spin_unlock(&syscon_list_slock); + + *ptr = syscon; + devres_add(dev, ptr); + + return 0; +} +EXPORT_SYMBOL_GPL(devm_syscon_register); + static int syscon_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct syscon_platform_data *pdata = dev_get_platdata(dev); - struct syscon *syscon; + struct regmap *regmap; struct resource *res; void __iomem *base; - - syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL); - if (!syscon) - return -ENOMEM; + int ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) @@ -144,14 +172,16 @@ static int syscon_probe(struct platform_device *pdev) syscon_regmap_config.max_register = res->end - res->start - 3; if (pdata) syscon_regmap_config.name = pdata->label; - syscon->regmap = devm_regmap_init_mmio(dev, base, + regmap = devm_regmap_init_mmio(dev, base, &syscon_regmap_config); - if (IS_ERR(syscon->regmap)) { + if (IS_ERR(regmap)) { dev_err(dev, "regmap init failed\n"); - return PTR_ERR(syscon->regmap); + return PTR_ERR(regmap); } - platform_set_drvdata(pdev, syscon); + ret = devm_syscon_register(dev, regmap); + if (ret) + return ret; dev_dbg(dev, "regmap %pR registered\n", res); diff --git a/include/linux/mfd/syscon.h b/include/linux/mfd/syscon.h index 75e543b..6a1cadf 100644 --- a/include/linux/mfd/syscon.h +++ b/include/linux/mfd/syscon.h @@ -18,8 +18,11 @@ #include struct device_node; +struct regmap; #ifdef CONFIG_MFD_SYSCON +extern int devm_syscon_register(struct device *dev, struct regmap *regmap); + extern struct regmap *syscon_node_to_regmap(struct device_node *np); extern struct regmap *syscon_regmap_lookup_by_compatible(const char *s); extern struct regmap *syscon_regmap_lookup_by_pdevname(const char *s); @@ -27,6 +30,12 @@ extern struct regmap *syscon_regmap_lookup_by_phandle( struct device_node *np, const char *property); #else +static inline int devm_syscon_register(struct device *dev, + struct regmap *regmap) +{ + return -ENOSYS; +} + static inline struct regmap *syscon_node_to_regmap(struct device_node *np) { return ERR_PTR(-ENOSYS); -- 1.9.3