diff options
Diffstat (limited to 'drivers/hwspinlock')
| -rw-r--r-- | drivers/hwspinlock/hwspinlock_core.c | 28 | ||||
| -rw-r--r-- | drivers/hwspinlock/hwspinlock_internal.h | 3 | ||||
| -rw-r--r-- | drivers/hwspinlock/qcom_hwspinlock.c | 25 |
3 files changed, 56 insertions, 0 deletions
diff --git a/drivers/hwspinlock/hwspinlock_core.c b/drivers/hwspinlock/hwspinlock_core.c index 0c0a932c00f3..6505261e6068 100644 --- a/drivers/hwspinlock/hwspinlock_core.c +++ b/drivers/hwspinlock/hwspinlock_core.c @@ -306,6 +306,34 @@ void __hwspin_unlock(struct hwspinlock *hwlock, int mode, unsigned long *flags) EXPORT_SYMBOL_GPL(__hwspin_unlock); /** + * hwspin_lock_bust() - bust a specific hwspinlock + * @hwlock: a previously-acquired hwspinlock which we want to bust + * @id: identifier of the remote lock holder, if applicable + * + * This function will bust a hwspinlock that was previously acquired as + * long as the current owner of the lock matches the id given by the caller. + * + * Context: Process context. + * + * Returns: 0 on success, or -EINVAL if the hwspinlock does not exist, or + * the bust operation fails, and -EOPNOTSUPP if the bust operation is not + * defined for the hwspinlock. + */ +int hwspin_lock_bust(struct hwspinlock *hwlock, unsigned int id) +{ + if (WARN_ON(!hwlock)) + return -EINVAL; + + if (!hwlock->bank->ops->bust) { + pr_err("bust operation not defined\n"); + return -EOPNOTSUPP; + } + + return hwlock->bank->ops->bust(hwlock, id); +} +EXPORT_SYMBOL_GPL(hwspin_lock_bust); + +/** * of_hwspin_lock_simple_xlate - translate hwlock_spec to return a lock id * @hwlock_spec: hwlock specifier as found in the device tree * diff --git a/drivers/hwspinlock/hwspinlock_internal.h b/drivers/hwspinlock/hwspinlock_internal.h index 29892767bb7a..f298fc0ee5ad 100644 --- a/drivers/hwspinlock/hwspinlock_internal.h +++ b/drivers/hwspinlock/hwspinlock_internal.h @@ -21,6 +21,8 @@ struct hwspinlock_device; * @trylock: make a single attempt to take the lock. returns 0 on * failure and true on success. may _not_ sleep. * @unlock: release the lock. always succeed. may _not_ sleep. + * @bust: optional, platform-specific bust handler, called by hwspinlock + * core to bust a specific lock. * @relax: optional, platform-specific relax handler, called by hwspinlock * core while spinning on a lock, between two successive * invocations of @trylock. may _not_ sleep. @@ -28,6 +30,7 @@ struct hwspinlock_device; struct hwspinlock_ops { int (*trylock)(struct hwspinlock *lock); void (*unlock)(struct hwspinlock *lock); + int (*bust)(struct hwspinlock *lock, unsigned int id); void (*relax)(struct hwspinlock *lock); }; diff --git a/drivers/hwspinlock/qcom_hwspinlock.c b/drivers/hwspinlock/qcom_hwspinlock.c index 814dfe8697bf..0390979fd765 100644 --- a/drivers/hwspinlock/qcom_hwspinlock.c +++ b/drivers/hwspinlock/qcom_hwspinlock.c @@ -64,9 +64,34 @@ static void qcom_hwspinlock_unlock(struct hwspinlock *lock) pr_err("%s: failed to unlock spinlock\n", __func__); } +static int qcom_hwspinlock_bust(struct hwspinlock *lock, unsigned int id) +{ + struct regmap_field *field = lock->priv; + u32 owner; + int ret; + + ret = regmap_field_read(field, &owner); + if (ret) { + dev_err(lock->bank->dev, "unable to query spinlock owner\n"); + return ret; + } + + if (owner != id) + return 0; + + ret = regmap_field_write(field, 0); + if (ret) { + dev_err(lock->bank->dev, "failed to bust spinlock\n"); + return ret; + } + + return 0; +} + static const struct hwspinlock_ops qcom_hwspinlock_ops = { .trylock = qcom_hwspinlock_trylock, .unlock = qcom_hwspinlock_unlock, + .bust = qcom_hwspinlock_bust, }; static const struct regmap_config sfpb_mutex_config = { |