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author | Jon Hunter <jonathanh@nvidia.com> | 2016-09-12 12:01:13 +0100 |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-09-13 02:49:34 +0200 |
commit | 3fe577107ccf1974958701df710e0b07ef16db75 (patch) | |
tree | 3dd76befaccad67978dd0db1e9ba898705067c00 /drivers/base/power/domain.c | |
parent | de0aa06d8b1c39df1071bfe169b3b97ca6bc01ac (diff) | |
download | op-kernel-dev-3fe577107ccf1974958701df710e0b07ef16db75.zip op-kernel-dev-3fe577107ccf1974958701df710e0b07ef16db75.tar.gz |
PM / Domains: Add support for removing PM domains
The genpd framework allows users to add PM domains via the pm_genpd_init()
function, however, there is no corresponding function to remove a PM
domain. For most devices this may be fine as the PM domains are never
removed, however, for devices that wish to populate the PM domains from
within a driver, having the ability to remove a PM domain if the probing
of the device fails or the driver is unloaded is necessary.
Add the function pm_genpd_remove() to remove a PM domain by referencing
it's generic_pm_domain structure. Note that the bulk of the code that
removes the PM domain is placed in a separate local function
genpd_remove() (which is called by pm_genpd_remove()). The code is
structured in this way to prepare for adding another function to remove
a PM domain by provider that will also call genpd_remove(). Note that
users of genpd_remove() must call this function with the mutex,
gpd_list_lock, held.
PM domains can only be removed if the associated provider has been
removed, they are not a parent domain to another PM domain and have no
devices associated with them.
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/base/power/domain.c')
-rw-r--r-- | drivers/base/power/domain.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index d5135ca..7481e3e 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -1358,6 +1358,66 @@ int pm_genpd_init(struct generic_pm_domain *genpd, } EXPORT_SYMBOL_GPL(pm_genpd_init); +static int genpd_remove(struct generic_pm_domain *genpd) +{ + struct gpd_link *l, *link; + + if (IS_ERR_OR_NULL(genpd)) + return -EINVAL; + + mutex_lock(&genpd->lock); + + if (genpd->has_provider) { + mutex_unlock(&genpd->lock); + pr_err("Provider present, unable to remove %s\n", genpd->name); + return -EBUSY; + } + + if (!list_empty(&genpd->master_links) || genpd->device_count) { + mutex_unlock(&genpd->lock); + pr_err("%s: unable to remove %s\n", __func__, genpd->name); + return -EBUSY; + } + + list_for_each_entry_safe(link, l, &genpd->slave_links, slave_node) { + list_del(&link->master_node); + list_del(&link->slave_node); + kfree(link); + } + + list_del(&genpd->gpd_list_node); + mutex_unlock(&genpd->lock); + cancel_work_sync(&genpd->power_off_work); + pr_debug("%s: removed %s\n", __func__, genpd->name); + + return 0; +} + +/** + * pm_genpd_remove - Remove a generic I/O PM domain + * @genpd: Pointer to PM domain that is to be removed. + * + * To remove the PM domain, this function: + * - Removes the PM domain as a subdomain to any parent domains, + * if it was added. + * - Removes the PM domain from the list of registered PM domains. + * + * The PM domain will only be removed, if the associated provider has + * been removed, it is not a parent to any other PM domain and has no + * devices associated with it. + */ +int pm_genpd_remove(struct generic_pm_domain *genpd) +{ + int ret; + + mutex_lock(&gpd_list_lock); + ret = genpd_remove(genpd); + mutex_unlock(&gpd_list_lock); + + return ret; +} +EXPORT_SYMBOL_GPL(pm_genpd_remove); + #ifdef CONFIG_PM_GENERIC_DOMAINS_OF typedef struct generic_pm_domain *(*genpd_xlate_t)(struct of_phandle_args *args, |