| Message ID | 1409215142-8218-3-git-send-email-ulf.hansson@linaro.org (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
Hi Ulf, Tomasz, On Thu, Aug 28, 2014 at 10:38 AM, Ulf Hansson <ulf.hansson@linaro.org> wrote: > From: Tomasz Figa <t.figa@samsung.com> > > This patch introduces generic code to perform power domain look-up using Should "power domain" be replaced by "PM domain" here (and everywhere else in this patch), too, cfr. Rafael's earlier comment? > +++ b/Documentation/devicetree/bindings/power/power_domain.txt > @@ -0,0 +1,51 @@ > +* Generic power domains > + > +System on chip designs are often divided into multiple power domains that > +can be used for power gating of selected IP blocks for power saving by > +reduced leakage current. > + > +This device tree binding can be used to bind power domain consumer devices > +with their power domains provided by power domain providers. A power domain > +provider can be represented by any node in the device tree and can provide > +one or more power domains. A consumer node can refer to the provider by > +a phandle and a set of phandle arguments (so called power domain specifier) specifiers > +of length specified by #power-domain-cells property in the power domain the #power-domain-cells property > +provider node. > + > +==Power domain providers== > + > +Required properties: > + - #power-domain-cells : Number of cells in a power domain specifier; > + Typically 0 for nodes representing a single power domain and 1 for nodes > + providing multiple power domains (e.g. power controllers), but can be > + any value as specified by device tree binding documentation of particular > + provider. > + > +Example: > + > + power: power-controller@12340000 { > + compatible = "foo,power-controller"; > + reg = <0x12340000 0x1000>; > + #power-domain-cells = <1>; > + }; > + > +The node above defines a power controller that is a power domain provider > +and expects one cell as its phandle argument. > + > +==Power domain consumers== > + > +Required properties: > + - power-domains : A phandle and power domain specifier as defined by bindings > + of power controller specified by phandle. the power controller > + > +Example: > + > + leaky-device@12350000 { > + compatible = "foo,i-leak-current"; > + reg = <0x12350000 0x1000>; > + power-domains = <&power 0>; > + }; > + > +The node above defines a typical power domain consumer device, which is located > +inside power domain with index 0 of power controller represented by node with the power domain ... the power controller ... the node > +label "power". > --- a/drivers/base/power/domain.c > +++ b/drivers/base/power/domain.c > +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF > +/* > + * Device Tree based power domain providers. > + * > + * The code below implements generic device tree based power domain providers > + * that bind device tree nodes with generic power domains registered in the > + * system. > + * > + * Any driver that registers generic power domains and need to support binding needs > + * of devices to these domains is supposed to register a power domain provider, > + * which maps a power domain specifier retrieved from device tree to a power the device tree > +/** > + * of_genpd_xlate_onecell() - Xlate function for providers using single index. a single index > + * @genpdspec: OF phandle args to map into a power domain > + * @data: xlate function private data - pointer to struct genpd_onecell_data > + * > + * This is a generic xlate function that can be used to model simple power > + * domain controllers that have one device tree node and provide multiple > + * power domains. A single cell is used as an index to an array of power an index into > + * domains specified in genpd_onecell_data struct when registering the the genpd_onecell_data struct > + * provider. > + */ > +struct generic_pm_domain *of_genpd_xlate_onecell( > + struct of_phandle_args *genpdspec, > + void *data) > +{ > + struct genpd_onecell_data *genpd_data = data; > + unsigned int idx = genpdspec->args[0]; > + > + if (genpdspec->args_count != 1) > + return ERR_PTR(-EINVAL); > + > + if (idx >= genpd_data->domain_num) { > + pr_err("%s: invalid domain index %d\n", __func__, idx); %u for unsigned int idx > + return ERR_PTR(-EINVAL); > + } > + > + return genpd_data->domains[idx]; This assumes ->domains[] is a contiguous array. I'd add a NULL check here, to translate NULL to ERR_PTR(-Esomething), so it can support sparse power domain spaces. E.g. indexed by the "bit_shift" value of struct rmobile_pm_domain, which is the actual bit number to use to power up/down an R-Mobile domain. Different members of the R-Mobile family have different numbers of domains, and use more or less bits in the same power up/down registers. This would be similar to the sparse clock-indices handling in renesas,cpg-mstp-clocks. > +} > +EXPORT_SYMBOL_GPL(of_genpd_xlate_onecell); > + > +/** > + * of_genpd_add_provider() - Register a domain provider for a node > + * @np: Device node pointer associated with domain provider. the domain provider > +/** > + * of_genpd_del_provider() - Remove a previously registered domain provider > + * @np: Device node pointer associated with domain provider the domain provider > +/** > + * of_genpd_get_from_provider() - Look-up power domain > + * @genpdspec: OF phandle args to use for look-up > + * > + * Looks for domain provider under node specified by @genpdspec and if found a domain provider ... under the node > + * uses xlate function of the provider to map phandle args to a power domain. > +/** > + * genpd_dev_pm_attach - Attach a device to it's power domain using DT. its > + * @dev: Device to attach. > +/** > + * genpd_dev_pm_detach - Detach a device from it's power domain. its > + * @dev: Device to attach. > + * > + * Try to locate a corresponding generic power domain, which the device > + * then previously were attached to. If found the device is detached from "was attached to previously"? > + * the power domain. > diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h > index 7c1d252..5989758 100644 > --- a/include/linux/pm_domain.h > +++ b/include/linux/pm_domain.h > @@ -310,4 +310,50 @@ static inline void pm_genpd_syscore_poweron(struct device *dev) > pm_genpd_syscore_switch(dev, false); > } > > +/* OF power domain providers */ > +struct of_device_id; > + > +struct genpd_onecell_data { > + struct generic_pm_domain **domains; > + unsigned int domain_num; This is the number of domains: "num_domains"? > +}; > + > +typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args, > + void *data); > + > +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF > +int of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate, > + void *data); > +void of_genpd_del_provider(struct device_node *np); > + > +struct generic_pm_domain *of_genpd_xlate_simple( > + struct of_phandle_args *genpdspec, > + void *data); > +struct generic_pm_domain *of_genpd_xlate_onecell( > + struct of_phandle_args *genpdspec, > + void *data); > + > +int genpd_dev_pm_attach(struct device *dev); > +int genpd_dev_pm_detach(struct device *dev); > +#else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ > +static inline int of_genpd_add_provider(struct device_node *np, > + genpd_xlate_t xlate, void *data) > +{ > + return 0; > +} > +static inline void of_genpd_del_provider(struct device_node *np) {} > + > +#define of_genpd_xlate_simple NULL > +#define of_genpd_xlate_onecell NULL > + > +static inline int genpd_dev_pm_attach(struct device *dev) > +{ > + return -ENODEV; > +} > +static inline int genpd_dev_pm_detach(struct device *dev) > +{ > + return -ENODEV; > +} > +#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ As of_genpd_add_provider() provides no compile-time type-checking for "void *data", I propose to prepend a double underscore to of_genpd_add_provider(), and to the xlate helpers of_genpd_xlate_simple() and of_genpd_xlate_onecell(), and provide type-checking wrappers: static inline int of_genpd_add_provider_simple(struct device_node *np, struct generic_pm_domain *genpd) { return __of_genpd_add_provider(np, __of_genpd_xlate_simple, genpd); } static inline int of_genpd_add_provider_onecell(struct device_node *np, struct genpd_onecell_data *data) { return __of_genpd_add_provider(np, __of_genpd_xlate_onecell, data); } Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2 September 2014 20:28, Geert Uytterhoeven <geert@linux-m68k.org> wrote: > Hi Ulf, Tomasz, > > On Thu, Aug 28, 2014 at 10:38 AM, Ulf Hansson <ulf.hansson@linaro.org> wrote: >> From: Tomasz Figa <t.figa@samsung.com> >> >> This patch introduces generic code to perform power domain look-up using > > Should "power domain" be replaced by "PM domain" here (and everywhere else > in this patch), too, cfr. Rafael's earlier comment? Hi Geert, Thanks for reviewing! I changed some of the other patches according to Rafael's earlier comment, but decided to keep this as is. The reason is that in drivers/base/power/domain.c there are already a mix between using "power domain" and "PM domain", thus I couldn't decide which way to go. I have no strong opinion of what terminology we use, I am happy to change this patch. Since I anyway will be sending new version, I will update to "PM domain". > >> +++ b/Documentation/devicetree/bindings/power/power_domain.txt >> @@ -0,0 +1,51 @@ >> +* Generic power domains >> + >> +System on chip designs are often divided into multiple power domains that >> +can be used for power gating of selected IP blocks for power saving by >> +reduced leakage current. >> + >> +This device tree binding can be used to bind power domain consumer devices >> +with their power domains provided by power domain providers. A power domain >> +provider can be represented by any node in the device tree and can provide >> +one or more power domains. A consumer node can refer to the provider by >> +a phandle and a set of phandle arguments (so called power domain specifier) > > specifiers > >> +of length specified by #power-domain-cells property in the power domain > > the #power-domain-cells property > >> +provider node. >> + >> +==Power domain providers== >> + >> +Required properties: >> + - #power-domain-cells : Number of cells in a power domain specifier; >> + Typically 0 for nodes representing a single power domain and 1 for nodes >> + providing multiple power domains (e.g. power controllers), but can be >> + any value as specified by device tree binding documentation of particular >> + provider. >> + >> +Example: >> + >> + power: power-controller@12340000 { >> + compatible = "foo,power-controller"; >> + reg = <0x12340000 0x1000>; >> + #power-domain-cells = <1>; >> + }; >> + >> +The node above defines a power controller that is a power domain provider >> +and expects one cell as its phandle argument. >> + >> +==Power domain consumers== >> + >> +Required properties: >> + - power-domains : A phandle and power domain specifier as defined by bindings >> + of power controller specified by phandle. > > the power controller > >> + >> +Example: >> + >> + leaky-device@12350000 { >> + compatible = "foo,i-leak-current"; >> + reg = <0x12350000 0x1000>; >> + power-domains = <&power 0>; >> + }; >> + >> +The node above defines a typical power domain consumer device, which is located >> +inside power domain with index 0 of power controller represented by node with > > the power domain ... the power controller ... the node > >> +label "power". > >> --- a/drivers/base/power/domain.c >> +++ b/drivers/base/power/domain.c > >> +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF >> +/* >> + * Device Tree based power domain providers. >> + * >> + * The code below implements generic device tree based power domain providers >> + * that bind device tree nodes with generic power domains registered in the >> + * system. >> + * >> + * Any driver that registers generic power domains and need to support binding > > needs > >> + * of devices to these domains is supposed to register a power domain provider, >> + * which maps a power domain specifier retrieved from device tree to a power > > the device tree > >> +/** >> + * of_genpd_xlate_onecell() - Xlate function for providers using single index. > > a single index > >> + * @genpdspec: OF phandle args to map into a power domain >> + * @data: xlate function private data - pointer to struct genpd_onecell_data >> + * >> + * This is a generic xlate function that can be used to model simple power >> + * domain controllers that have one device tree node and provide multiple >> + * power domains. A single cell is used as an index to an array of power > > an index into > >> + * domains specified in genpd_onecell_data struct when registering the > > the genpd_onecell_data struct > >> + * provider. >> + */ >> +struct generic_pm_domain *of_genpd_xlate_onecell( >> + struct of_phandle_args *genpdspec, >> + void *data) >> +{ >> + struct genpd_onecell_data *genpd_data = data; >> + unsigned int idx = genpdspec->args[0]; >> + >> + if (genpdspec->args_count != 1) >> + return ERR_PTR(-EINVAL); >> + >> + if (idx >= genpd_data->domain_num) { >> + pr_err("%s: invalid domain index %d\n", __func__, idx); > > %u for unsigned int idx > >> + return ERR_PTR(-EINVAL); >> + } >> + >> + return genpd_data->domains[idx]; > > This assumes ->domains[] is a contiguous array. > > I'd add a NULL check here, to translate NULL to ERR_PTR(-Esomething), > so it can support sparse power domain spaces. > E.g. indexed by the "bit_shift" value of struct rmobile_pm_domain, which > is the actual bit number to use to power up/down an R-Mobile domain. > Different members of the R-Mobile family have different numbers of > domains, and use more or less bits in the same power up/down registers. > This would be similar to the sparse clock-indices handling in > renesas,cpg-mstp-clocks. > OK, will do! >> +} >> +EXPORT_SYMBOL_GPL(of_genpd_xlate_onecell); >> + >> +/** >> + * of_genpd_add_provider() - Register a domain provider for a node >> + * @np: Device node pointer associated with domain provider. > > the domain provider > >> +/** >> + * of_genpd_del_provider() - Remove a previously registered domain provider >> + * @np: Device node pointer associated with domain provider > > the domain provider > >> +/** >> + * of_genpd_get_from_provider() - Look-up power domain >> + * @genpdspec: OF phandle args to use for look-up >> + * >> + * Looks for domain provider under node specified by @genpdspec and if found > > a domain provider ... under the node > >> + * uses xlate function of the provider to map phandle args to a power domain. > >> +/** >> + * genpd_dev_pm_attach - Attach a device to it's power domain using DT. > > its > >> + * @dev: Device to attach. > >> +/** >> + * genpd_dev_pm_detach - Detach a device from it's power domain. > > its > >> + * @dev: Device to attach. >> + * >> + * Try to locate a corresponding generic power domain, which the device >> + * then previously were attached to. If found the device is detached from > > "was attached to previously"? > >> + * the power domain. > >> diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h >> index 7c1d252..5989758 100644 >> --- a/include/linux/pm_domain.h >> +++ b/include/linux/pm_domain.h >> @@ -310,4 +310,50 @@ static inline void pm_genpd_syscore_poweron(struct device *dev) >> pm_genpd_syscore_switch(dev, false); >> } >> >> +/* OF power domain providers */ >> +struct of_device_id; >> + >> +struct genpd_onecell_data { >> + struct generic_pm_domain **domains; >> + unsigned int domain_num; > > This is the number of domains: "num_domains"? OK, that describes it better. > >> +}; >> + >> +typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args, >> + void *data); >> + >> +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF >> +int of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate, >> + void *data); >> +void of_genpd_del_provider(struct device_node *np); >> + >> +struct generic_pm_domain *of_genpd_xlate_simple( >> + struct of_phandle_args *genpdspec, >> + void *data); >> +struct generic_pm_domain *of_genpd_xlate_onecell( >> + struct of_phandle_args *genpdspec, >> + void *data); >> + >> +int genpd_dev_pm_attach(struct device *dev); >> +int genpd_dev_pm_detach(struct device *dev); >> +#else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ >> +static inline int of_genpd_add_provider(struct device_node *np, >> + genpd_xlate_t xlate, void *data) >> +{ >> + return 0; >> +} >> +static inline void of_genpd_del_provider(struct device_node *np) {} >> + >> +#define of_genpd_xlate_simple NULL >> +#define of_genpd_xlate_onecell NULL >> + >> +static inline int genpd_dev_pm_attach(struct device *dev) >> +{ >> + return -ENODEV; >> +} >> +static inline int genpd_dev_pm_detach(struct device *dev) >> +{ >> + return -ENODEV; >> +} >> +#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ > > As of_genpd_add_provider() provides no compile-time type-checking for > "void *data", I propose to prepend a double underscore to > of_genpd_add_provider(), and to the xlate helpers of_genpd_xlate_simple() > and of_genpd_xlate_onecell(), and provide type-checking wrappers: > Good idea, I will give it a try in next version. > static inline int of_genpd_add_provider_simple(struct device_node *np, > struct generic_pm_domain *genpd) > { > return __of_genpd_add_provider(np, __of_genpd_xlate_simple, genpd); > } > static inline int of_genpd_add_provider_onecell(struct device_node *np, > struct genpd_onecell_data *data) > { > return __of_genpd_add_provider(np, __of_genpd_xlate_onecell, data); > } > Thanks for all the grammar/English corrections as well. Will update. Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/power/power_domain.txt b/Documentation/devicetree/bindings/power/power_domain.txt new file mode 100644 index 0000000..303d0a9 --- /dev/null +++ b/Documentation/devicetree/bindings/power/power_domain.txt @@ -0,0 +1,51 @@ +* Generic power domains + +System on chip designs are often divided into multiple power domains that +can be used for power gating of selected IP blocks for power saving by +reduced leakage current. + +This device tree binding can be used to bind power domain consumer devices +with their power domains provided by power domain providers. A power domain +provider can be represented by any node in the device tree and can provide +one or more power domains. A consumer node can refer to the provider by +a phandle and a set of phandle arguments (so called power domain specifier) +of length specified by #power-domain-cells property in the power domain +provider node. + +==Power domain providers== + +Required properties: + - #power-domain-cells : Number of cells in a power domain specifier; + Typically 0 for nodes representing a single power domain and 1 for nodes + providing multiple power domains (e.g. power controllers), but can be + any value as specified by device tree binding documentation of particular + provider. + +Example: + + power: power-controller@12340000 { + compatible = "foo,power-controller"; + reg = <0x12340000 0x1000>; + #power-domain-cells = <1>; + }; + +The node above defines a power controller that is a power domain provider +and expects one cell as its phandle argument. + +==Power domain consumers== + +Required properties: + - power-domains : A phandle and power domain specifier as defined by bindings + of power controller specified by phandle. + +Example: + + leaky-device@12350000 { + compatible = "foo,i-leak-current"; + reg = <0x12350000 0x1000>; + power-domains = <&power 0>; + }; + +The node above defines a typical power domain consumer device, which is located +inside power domain with index 0 of power controller represented by node with +label "power". diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index eee55c1..0fb26e5 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -8,6 +8,7 @@ #include <linux/kernel.h> #include <linux/io.h> +#include <linux/platform_device.h> #include <linux/pm_runtime.h> #include <linux/pm_domain.h> #include <linux/pm_qos.h> @@ -2189,3 +2190,293 @@ void pm_genpd_init(struct generic_pm_domain *genpd, list_add(&genpd->gpd_list_node, &gpd_list); mutex_unlock(&gpd_list_lock); } + +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF +/* + * Device Tree based power domain providers. + * + * The code below implements generic device tree based power domain providers + * that bind device tree nodes with generic power domains registered in the + * system. + * + * Any driver that registers generic power domains and need to support binding + * of devices to these domains is supposed to register a power domain provider, + * which maps a power domain specifier retrieved from device tree to a power + * domain. + * + * Two simple mapping functions have been provided for convenience: + * - of_genpd_xlate_simple() for 1:1 device tree node to domain mapping, + * - of_genpd_xlate_onecell() for mapping of multiple domains per node + * by index. + */ + +/** + * struct of_genpd_provider - Power domain provider registration structure + * @link: Entry in global list of domain providers + * @node: Pointer to device tree node of domain provider + * @xlate: Provider-specific xlate callback mapping a set of specifier cells + * into a power domain. + * @data: context pointer to be passed into @xlate callback + */ +struct of_genpd_provider { + struct list_head link; + struct device_node *node; + genpd_xlate_t xlate; + void *data; +}; + +/* List of registered power domain providers. */ +static LIST_HEAD(of_genpd_providers); +/* Mutex to protect the list above. */ +static DEFINE_MUTEX(of_genpd_mutex); + +/** + * of_genpd_xlate_simple() - Xlate function for direct node-domain mapping + * @genpdspec: OF phandle args to map into a power domain + * @data: xlate function private data - pointer to struct generic_pm_domain + * + * This is a generic xlate function that can be used to model power domains + * that have their own device tree nodes. The private data of xlate function + * needs to be a valid pointer to struct generic_pm_domain. + */ +struct generic_pm_domain *of_genpd_xlate_simple( + struct of_phandle_args *genpdspec, + void *data) +{ + if (genpdspec->args_count != 0) + return ERR_PTR(-EINVAL); + return data; +} +EXPORT_SYMBOL_GPL(of_genpd_xlate_simple); + +/** + * of_genpd_xlate_onecell() - Xlate function for providers using single index. + * @genpdspec: OF phandle args to map into a power domain + * @data: xlate function private data - pointer to struct genpd_onecell_data + * + * This is a generic xlate function that can be used to model simple power + * domain controllers that have one device tree node and provide multiple + * power domains. A single cell is used as an index to an array of power + * domains specified in genpd_onecell_data struct when registering the + * provider. + */ +struct generic_pm_domain *of_genpd_xlate_onecell( + struct of_phandle_args *genpdspec, + void *data) +{ + struct genpd_onecell_data *genpd_data = data; + unsigned int idx = genpdspec->args[0]; + + if (genpdspec->args_count != 1) + return ERR_PTR(-EINVAL); + + if (idx >= genpd_data->domain_num) { + pr_err("%s: invalid domain index %d\n", __func__, idx); + return ERR_PTR(-EINVAL); + } + + return genpd_data->domains[idx]; +} +EXPORT_SYMBOL_GPL(of_genpd_xlate_onecell); + +/** + * of_genpd_add_provider() - Register a domain provider for a node + * @np: Device node pointer associated with domain provider. + * @xlate: Callback for decoding domain from phandle arguments. + * @data: Context pointer for @genpd_src_get callback. + */ +int of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate, + void *data) +{ + struct of_genpd_provider *cp; + + cp = kzalloc(sizeof(*cp), GFP_KERNEL); + if (!cp) + return -ENOMEM; + + cp->node = of_node_get(np); + cp->data = data; + cp->xlate = xlate; + + mutex_lock(&of_genpd_mutex); + list_add(&cp->link, &of_genpd_providers); + mutex_unlock(&of_genpd_mutex); + pr_debug("Added domain provider from %s\n", np->full_name); + + return 0; +} +EXPORT_SYMBOL_GPL(of_genpd_add_provider); + +/** + * of_genpd_del_provider() - Remove a previously registered domain provider + * @np: Device node pointer associated with domain provider + */ +void of_genpd_del_provider(struct device_node *np) +{ + struct of_genpd_provider *cp; + + mutex_lock(&of_genpd_mutex); + list_for_each_entry(cp, &of_genpd_providers, link) { + if (cp->node == np) { + list_del(&cp->link); + of_node_put(cp->node); + kfree(cp); + break; + } + } + mutex_unlock(&of_genpd_mutex); +} +EXPORT_SYMBOL_GPL(of_genpd_del_provider); + +/** + * of_genpd_get_from_provider() - Look-up power domain + * @genpdspec: OF phandle args to use for look-up + * + * Looks for domain provider under node specified by @genpdspec and if found + * uses xlate function of the provider to map phandle args to a power domain. + * + * Returns a valid pointer to struct generic_pm_domain on success or ERR_PTR() + * on failure. + */ +static struct generic_pm_domain *of_genpd_get_from_provider( + struct of_phandle_args *genpdspec) +{ + struct generic_pm_domain *genpd = ERR_PTR(-ENOENT); + struct of_genpd_provider *provider; + + mutex_lock(&of_genpd_mutex); + + /* Check if we have such a provider in our array */ + list_for_each_entry(provider, &of_genpd_providers, link) { + if (provider->node == genpdspec->np) + genpd = provider->xlate(genpdspec, provider->data); + if (!IS_ERR(genpd)) + break; + } + + mutex_unlock(&of_genpd_mutex); + + return genpd; +} + +/** + * genpd_dev_pm_attach - Attach a device to it's power domain using DT. + * @dev: Device to attach. + * + * Parse device's OF node to find a power domain specifier. If such is found, + * attaches the device to retrieved pm_domain ops. + * + * Both generic and legacy Samsung-specific DT bindings are supported to + * keep backwards compatibility with existing DTBs. + * + * Returns 0 on successfully attached power domain or negative error code. + */ +int genpd_dev_pm_attach(struct device *dev) +{ + struct of_phandle_args pd_args; + struct generic_pm_domain *pd; + int ret; + + if (!dev->of_node) + return -ENODEV; + + if (dev->pm_domain) + return -EEXIST; + + ret = of_parse_phandle_with_args(dev->of_node, "power-domains", + "#power-domain-cells", 0, &pd_args); + if (ret < 0) { + if (ret != -ENOENT) + return ret; + + /* + * Try legacy Samsung-specific bindings + * (for backwards compatibility of DT ABI) + */ + pd_args.args_count = 0; + pd_args.np = of_parse_phandle(dev->of_node, + "samsung,power-domain", 0); + if (!pd_args.np) + return -ENOENT; + } + + pd = of_genpd_get_from_provider(&pd_args); + if (IS_ERR(pd)) { + dev_dbg(dev, "%s() failed to find power domain: %ld\n", + __func__, PTR_ERR(pd)); + of_node_put(dev->of_node); + return PTR_ERR(pd); + } + + dev_dbg(dev, "adding to power domain %s\n", pd->name); + + while (1) { + ret = pm_genpd_add_device(pd, dev); + if (ret != -EAGAIN) + break; + cond_resched(); + } + + if (ret < 0) { + dev_err(dev, "failed to add to power domain %s: %d", + pd->name, ret); + of_node_put(dev->of_node); + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(genpd_dev_pm_attach); + +/** + * genpd_dev_pm_detach - Detach a device from it's power domain. + * @dev: Device to attach. + * + * Try to locate a corresponding generic power domain, which the device + * then previously were attached to. If found the device is detached from + * the power domain. + * + * Returns 0 on successfully detached power domain or negative error code. + */ +int genpd_dev_pm_detach(struct device *dev) +{ + struct generic_pm_domain *pd = NULL, *gpd; + int ret = 0; + + if (!dev->pm_domain) + return -ENODEV; + + mutex_lock(&gpd_list_lock); + list_for_each_entry(gpd, &gpd_list, gpd_list_node) { + if (&gpd->domain == dev->pm_domain) { + pd = gpd; + break; + } + } + mutex_unlock(&gpd_list_lock); + + if (!pd) + return -ENOENT; + + dev_dbg(dev, "removing from power domain %s\n", pd->name); + + while (1) { + ret = pm_genpd_remove_device(pd, dev); + if (ret != -EAGAIN) + break; + cond_resched(); + } + + if (ret < 0) { + dev_err(dev, "failed to remove from power domain %s: %d", + pd->name, ret); + return ret; + } + + /* Check if domain can be powered off after removing this device. */ + genpd_queue_power_off_work(pd); + + return 0; +} +EXPORT_SYMBOL_GPL(genpd_dev_pm_detach); +#endif diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index 7c1d252..5989758 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -310,4 +310,50 @@ static inline void pm_genpd_syscore_poweron(struct device *dev) pm_genpd_syscore_switch(dev, false); } +/* OF power domain providers */ +struct of_device_id; + +struct genpd_onecell_data { + struct generic_pm_domain **domains; + unsigned int domain_num; +}; + +typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args, + void *data); + +#ifdef CONFIG_PM_GENERIC_DOMAINS_OF +int of_genpd_add_provider(struct device_node *np, genpd_xlate_t xlate, + void *data); +void of_genpd_del_provider(struct device_node *np); + +struct generic_pm_domain *of_genpd_xlate_simple( + struct of_phandle_args *genpdspec, + void *data); +struct generic_pm_domain *of_genpd_xlate_onecell( + struct of_phandle_args *genpdspec, + void *data); + +int genpd_dev_pm_attach(struct device *dev); +int genpd_dev_pm_detach(struct device *dev); +#else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ +static inline int of_genpd_add_provider(struct device_node *np, + genpd_xlate_t xlate, void *data) +{ + return 0; +} +static inline void of_genpd_del_provider(struct device_node *np) {} + +#define of_genpd_xlate_simple NULL +#define of_genpd_xlate_onecell NULL + +static inline int genpd_dev_pm_attach(struct device *dev) +{ + return -ENODEV; +} +static inline int genpd_dev_pm_detach(struct device *dev) +{ + return -ENODEV; +} +#endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ + #endif /* _LINUX_PM_DOMAIN_H */ diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index e4e4121..897619b 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -302,6 +302,10 @@ config PM_GENERIC_DOMAINS_RUNTIME def_bool y depends on PM_RUNTIME && PM_GENERIC_DOMAINS +config PM_GENERIC_DOMAINS_OF + def_bool y + depends on PM_GENERIC_DOMAINS && OF && !ARCH_EXYNOS + config CPU_PM bool depends on SUSPEND || CPU_IDLE