| Message ID | 1475879821-8035-4-git-send-email-lina.iyer@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
On 8 October 2016 at 00:36, Lina Iyer <lina.iyer@linaro.org> wrote: > This patch allows domains to define idle states in the DT. SoC's can > define domain idle states in DT using the "domain-idle-states" property > of the domain provider. Add API to read the idle states from DT that can > be set in the genpd object. > > This patch is based on the original patch by Marc Titinger. > > Signed-off-by: Marc Titinger <mtitinger+renesas@baylibre.com> > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> > Signed-off-by: Lina Iyer <lina.iyer@linaro.org> > --- > drivers/base/power/domain.c | 95 +++++++++++++++++++++++++++++++++++++++++++++ > include/linux/pm_domain.h | 8 ++++ > 2 files changed, 103 insertions(+) > > diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c > index 4e87170..4208b67 100644 > --- a/drivers/base/power/domain.c > +++ b/drivers/base/power/domain.c > @@ -1917,6 +1917,101 @@ out: > return ret ? -EPROBE_DEFER : 0; > } > EXPORT_SYMBOL_GPL(genpd_dev_pm_attach); > + > +static const struct of_device_id idle_state_match[] = { > + { .compatible = "arm,idle-state", }, > + { } > +}; > + > +static int genpd_parse_state(struct genpd_power_state *genpd_state, > + struct device_node *state_node) > +{ > + int err; > + u32 residency; > + u32 entry_latency, exit_latency; > + const struct of_device_id *match_id; > + > + match_id = of_match_node(idle_state_match, state_node); > + if (!match_id) > + return -EINVAL; > + > + err = of_property_read_u32(state_node, "entry-latency-us", > + &entry_latency); > + if (err) { > + pr_debug(" * %s missing entry-latency-us property\n", > + state_node->full_name); > + return -EINVAL; > + } > + > + err = of_property_read_u32(state_node, "exit-latency-us", > + &exit_latency); > + if (err) { > + pr_debug(" * %s missing exit-latency-us property\n", > + state_node->full_name); > + return -EINVAL; > + } > + > + err = of_property_read_u32(state_node, "min-residency-us", &residency); > + if (!err) > + genpd_state->residency_ns = 1000 * residency; > + > + genpd_state->power_on_latency_ns = 1000 * exit_latency; > + genpd_state->power_off_latency_ns = 1000 * entry_latency; > + > + return 0; > +} > + > +/** > + * of_genpd_parse_idle_states: Return array of idle states for the genpd. > + * > + * @dn: The genpd device node > + * @states: The pointer to which the state array will be saved. > + * @n: The count of elements in the array returned from this function. > + * > + * Returns the device states parsed from the OF node. The memory for the states > + * is allocated by this function and is the responsibility of the caller to > + * free the memory after use. > + */ > +int of_genpd_parse_idle_states(struct device_node *dn, > + struct genpd_power_state **states, int *n) Instead of taking **states as a parameter, let's instead return it as a pointer for the allocated struct. In case of failures, let's return ERR_PTR(). > +{ > + struct genpd_power_state *st; > + struct device_node *np; > + int i = 0; > + int err, ret; > + int count; > + struct of_phandle_iterator it; > + > + count = of_count_phandle_with_args(dn, "domain-idle-states", NULL); If count is zero or an error, we should return an error code (ERR_PTR()). Right? > + > + st = kcalloc(count, sizeof(*st), GFP_KERNEL); > + if (!st) > + return -ENOMEM; > + > + /* Loop over the phandles until all the requested entry is found */ > + of_for_each_phandle(&it, err, dn, "domain-idle-states", NULL, 0) { > + np = of_node_get(it.node); I don't think you need to increment the usage count for the device node as that is already managed by of_for_each_phandle(). It's only in the error case below, when it's needed. > + ret = genpd_parse_state(&st[i++], np); > + if (ret) { > + pr_err > + ("Parsing idle state node %s failed with err %d\n", > + np->full_name, ret); > + of_node_put(np); > + goto fail; The goto seems unnecessary. Why not deal with all error handling here and return the error code? > + } > + of_node_put(np); According the comment above, you should be able to remove this. > + } > + > + *n = count; > + *states = st; > + > + return 0; > +fail: > + kfree(st); > + return ret; > +} > +EXPORT_SYMBOL(of_genpd_parse_idle_states); Please use EXPORT_SYMBOL_GPL() instead. > + > #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ > > > diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h > index f4492eb..b489496 100644 > --- a/include/linux/pm_domain.h > +++ b/include/linux/pm_domain.h > @@ -205,6 +205,8 @@ extern int of_genpd_add_device(struct of_phandle_args *args, > extern int of_genpd_add_subdomain(struct of_phandle_args *parent, > struct of_phandle_args *new_subdomain); > extern struct generic_pm_domain *of_genpd_remove_last(struct device_node *np); > +extern int of_genpd_parse_idle_states(struct device_node *dn, > + struct genpd_power_state **states, int *n); > > int genpd_dev_pm_attach(struct device *dev); > #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ > @@ -234,6 +236,12 @@ static inline int of_genpd_add_subdomain(struct of_phandle_args *parent, > return -ENODEV; > } > > +static inline int of_genpd_parse_idle_states(struct device_node *dn, > + struct genpd_power_state **states, int *n) > +{ > + return -ENODEV; > +} > + > static inline int genpd_dev_pm_attach(struct device *dev) > { > return -ENODEV; > -- > 2.7.4 > Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
[...] >>> +int of_genpd_parse_idle_states(struct device_node *dn, >>> + struct genpd_power_state **states, int *n) >> >> >> Instead of taking **states as a parameter, let's instead return it as >> a pointer for the allocated struct. In case of failures, let's return >> ERR_PTR(). >> > Hmm.. I thought about it. There are 2 return values from this function. > If we return a pointer to the allocated memory, we still have to return > the size of it as an argument. I wasn't happy splitting the return > values in 2 different places. Ahh, right. So let's keep it as is! [...] Kind regards Uffe -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" 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/drivers/base/power/domain.c b/drivers/base/power/domain.c index 4e87170..4208b67 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1917,6 +1917,101 @@ out: return ret ? -EPROBE_DEFER : 0; } EXPORT_SYMBOL_GPL(genpd_dev_pm_attach); + +static const struct of_device_id idle_state_match[] = { + { .compatible = "arm,idle-state", }, + { } +}; + +static int genpd_parse_state(struct genpd_power_state *genpd_state, + struct device_node *state_node) +{ + int err; + u32 residency; + u32 entry_latency, exit_latency; + const struct of_device_id *match_id; + + match_id = of_match_node(idle_state_match, state_node); + if (!match_id) + return -EINVAL; + + err = of_property_read_u32(state_node, "entry-latency-us", + &entry_latency); + if (err) { + pr_debug(" * %s missing entry-latency-us property\n", + state_node->full_name); + return -EINVAL; + } + + err = of_property_read_u32(state_node, "exit-latency-us", + &exit_latency); + if (err) { + pr_debug(" * %s missing exit-latency-us property\n", + state_node->full_name); + return -EINVAL; + } + + err = of_property_read_u32(state_node, "min-residency-us", &residency); + if (!err) + genpd_state->residency_ns = 1000 * residency; + + genpd_state->power_on_latency_ns = 1000 * exit_latency; + genpd_state->power_off_latency_ns = 1000 * entry_latency; + + return 0; +} + +/** + * of_genpd_parse_idle_states: Return array of idle states for the genpd. + * + * @dn: The genpd device node + * @states: The pointer to which the state array will be saved. + * @n: The count of elements in the array returned from this function. + * + * Returns the device states parsed from the OF node. The memory for the states + * is allocated by this function and is the responsibility of the caller to + * free the memory after use. + */ +int of_genpd_parse_idle_states(struct device_node *dn, + struct genpd_power_state **states, int *n) +{ + struct genpd_power_state *st; + struct device_node *np; + int i = 0; + int err, ret; + int count; + struct of_phandle_iterator it; + + count = of_count_phandle_with_args(dn, "domain-idle-states", NULL); + + st = kcalloc(count, sizeof(*st), GFP_KERNEL); + if (!st) + return -ENOMEM; + + /* Loop over the phandles until all the requested entry is found */ + of_for_each_phandle(&it, err, dn, "domain-idle-states", NULL, 0) { + np = of_node_get(it.node); + ret = genpd_parse_state(&st[i++], np); + if (ret) { + pr_err + ("Parsing idle state node %s failed with err %d\n", + np->full_name, ret); + of_node_put(np); + goto fail; + } + of_node_put(np); + } + + *n = count; + *states = st; + + return 0; +fail: + kfree(st); + return ret; +} +EXPORT_SYMBOL(of_genpd_parse_idle_states); + #endif /* CONFIG_PM_GENERIC_DOMAINS_OF */ diff --git a/include/linux/pm_domain.h b/include/linux/pm_domain.h index f4492eb..b489496 100644 --- a/include/linux/pm_domain.h +++ b/include/linux/pm_domain.h @@ -205,6 +205,8 @@ extern int of_genpd_add_device(struct of_phandle_args *args, extern int of_genpd_add_subdomain(struct of_phandle_args *parent, struct of_phandle_args *new_subdomain); extern struct generic_pm_domain *of_genpd_remove_last(struct device_node *np); +extern int of_genpd_parse_idle_states(struct device_node *dn, + struct genpd_power_state **states, int *n); int genpd_dev_pm_attach(struct device *dev); #else /* !CONFIG_PM_GENERIC_DOMAINS_OF */ @@ -234,6 +236,12 @@ static inline int of_genpd_add_subdomain(struct of_phandle_args *parent, return -ENODEV; } +static inline int of_genpd_parse_idle_states(struct device_node *dn, + struct genpd_power_state **states, int *n) +{ + return -ENODEV; +} + static inline int genpd_dev_pm_attach(struct device *dev) { return -ENODEV;