diff options
| -rw-r--r-- | drivers/reset/core.c | 31 |
1 files changed, 25 insertions, 6 deletions
diff --git a/drivers/reset/core.c b/drivers/reset/core.c index c8fb4426b218..1d21c6f7d56c 100644 --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -280,9 +280,6 @@ int reset_control_assert(struct reset_control *rstc) if (reset_control_is_array(rstc)) return reset_control_array_assert(rstc_to_array(rstc)); - if (!rstc->rcdev->ops->assert) - return -ENOTSUPP; - if (rstc->shared) { if (WARN_ON(atomic_read(&rstc->triggered_count) != 0)) return -EINVAL; @@ -292,6 +289,21 @@ int reset_control_assert(struct reset_control *rstc) if (atomic_dec_return(&rstc->deassert_count) != 0) return 0; + + /* + * Shared reset controls allow the reset line to be in any state + * after this call, so doing nothing is a valid option. + */ + if (!rstc->rcdev->ops->assert) + return 0; + } else { + /* + * If the reset controller does not implement .assert(), there + * is no way to guarantee that the reset line is asserted after + * this call. + */ + if (!rstc->rcdev->ops->assert) + return -ENOTSUPP; } return rstc->rcdev->ops->assert(rstc->rcdev, rstc->id); @@ -321,9 +333,6 @@ int reset_control_deassert(struct reset_control *rstc) if (reset_control_is_array(rstc)) return reset_control_array_deassert(rstc_to_array(rstc)); - if (!rstc->rcdev->ops->deassert) - return -ENOTSUPP; - if (rstc->shared) { if (WARN_ON(atomic_read(&rstc->triggered_count) != 0)) return -EINVAL; @@ -332,6 +341,16 @@ int reset_control_deassert(struct reset_control *rstc) return 0; } + /* + * If the reset controller does not implement .deassert(), we assume + * that it handles self-deasserting reset lines via .reset(). In that + * case, the reset lines are deasserted by default. If that is not the + * case, the reset controller driver should implement .deassert() and + * return -ENOTSUPP. + */ + if (!rstc->rcdev->ops->deassert) + return 0; + return rstc->rcdev->ops->deassert(rstc->rcdev, rstc->id); } EXPORT_SYMBOL_GPL(reset_control_deassert); |