diff options
Diffstat (limited to 'drivers/base/core.c')
| -rw-r--r-- | drivers/base/core.c | 98 |
1 files changed, 89 insertions, 9 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c index 14d46af40f9a..b93f3c5716ae 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -92,12 +92,13 @@ static int __fwnode_link_add(struct fwnode_handle *con, return 0; } -int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup) +int fwnode_link_add(struct fwnode_handle *con, struct fwnode_handle *sup, + u8 flags) { int ret; mutex_lock(&fwnode_link_lock); - ret = __fwnode_link_add(con, sup, 0); + ret = __fwnode_link_add(con, sup, flags); mutex_unlock(&fwnode_link_lock); return ret; } @@ -125,7 +126,7 @@ static void __fwnode_link_del(struct fwnode_link *link) */ static void __fwnode_link_cycle(struct fwnode_link *link) { - pr_debug("%pfwf: Relaxing link with %pfwf\n", + pr_debug("%pfwf: cycle: depends on %pfwf\n", link->consumer, link->supplier); link->flags |= FWLINK_FLAG_CYCLE; } @@ -284,10 +285,12 @@ static bool device_is_ancestor(struct device *dev, struct device *target) return false; } +#define DL_MARKER_FLAGS (DL_FLAG_INFERRED | \ + DL_FLAG_CYCLE | \ + DL_FLAG_MANAGED) static inline bool device_link_flag_is_sync_state_only(u32 flags) { - return (flags & ~(DL_FLAG_INFERRED | DL_FLAG_CYCLE)) == - (DL_FLAG_SYNC_STATE_ONLY | DL_FLAG_MANAGED); + return (flags & ~DL_MARKER_FLAGS) == DL_FLAG_SYNC_STATE_ONLY; } /** @@ -1009,7 +1012,8 @@ static struct fwnode_handle *fwnode_links_check_suppliers( return NULL; list_for_each_entry(link, &fwnode->suppliers, c_hook) - if (!(link->flags & FWLINK_FLAG_CYCLE)) + if (!(link->flags & + (FWLINK_FLAG_CYCLE | FWLINK_FLAG_IGNORE))) return link->supplier; return NULL; @@ -1869,6 +1873,7 @@ static void fw_devlink_unblock_consumers(struct device *dev) device_links_write_unlock(); } +#define get_dev_from_fwnode(fwnode) get_device((fwnode)->dev) static bool fwnode_init_without_drv(struct fwnode_handle *fwnode) { @@ -1900,6 +1905,63 @@ static bool fwnode_ancestor_init_without_drv(struct fwnode_handle *fwnode) } /** + * fwnode_is_ancestor_of - Test if @ancestor is ancestor of @child + * @ancestor: Firmware which is tested for being an ancestor + * @child: Firmware which is tested for being the child + * + * A node is considered an ancestor of itself too. + * + * Return: true if @ancestor is an ancestor of @child. Otherwise, returns false. + */ +static bool fwnode_is_ancestor_of(const struct fwnode_handle *ancestor, + const struct fwnode_handle *child) +{ + struct fwnode_handle *parent; + + if (IS_ERR_OR_NULL(ancestor)) + return false; + + if (child == ancestor) + return true; + + fwnode_for_each_parent_node(child, parent) { + if (parent == ancestor) { + fwnode_handle_put(parent); + return true; + } + } + return false; +} + +/** + * fwnode_get_next_parent_dev - Find device of closest ancestor fwnode + * @fwnode: firmware node + * + * Given a firmware node (@fwnode), this function finds its closest ancestor + * firmware node that has a corresponding struct device and returns that struct + * device. + * + * The caller is responsible for calling put_device() on the returned device + * pointer. + * + * Return: a pointer to the device of the @fwnode's closest ancestor. + */ +static struct device *fwnode_get_next_parent_dev(const struct fwnode_handle *fwnode) +{ + struct fwnode_handle *parent; + struct device *dev; + + fwnode_for_each_parent_node(fwnode, parent) { + dev = get_dev_from_fwnode(parent); + if (dev) { + fwnode_handle_put(parent); + return dev; + } + } + return NULL; +} + +/** * __fw_devlink_relax_cycles - Relax and mark dependency cycles. * @con: Potential consumer device. * @sup_handle: Potential supplier's fwnode. @@ -1943,6 +2005,7 @@ static bool __fw_devlink_relax_cycles(struct device *con, /* Termination condition. */ if (sup_dev == con) { + pr_debug("----- cycle: start -----\n"); ret = true; goto out; } @@ -1959,6 +2022,9 @@ static bool __fw_devlink_relax_cycles(struct device *con, } list_for_each_entry(link, &sup_handle->suppliers, c_hook) { + if (link->flags & FWLINK_FLAG_IGNORE) + continue; + if (__fw_devlink_relax_cycles(con, link->supplier)) { __fwnode_link_cycle(link); ret = true; @@ -1974,8 +2040,11 @@ static bool __fw_devlink_relax_cycles(struct device *con, else par_dev = fwnode_get_next_parent_dev(sup_handle); - if (par_dev && __fw_devlink_relax_cycles(con, par_dev->fwnode)) + if (par_dev && __fw_devlink_relax_cycles(con, par_dev->fwnode)) { + pr_debug("%pfwf: cycle: child of %pfwf\n", sup_handle, + par_dev->fwnode); ret = true; + } if (!sup_dev) goto out; @@ -1991,6 +2060,8 @@ static bool __fw_devlink_relax_cycles(struct device *con, if (__fw_devlink_relax_cycles(con, dev_link->supplier->fwnode)) { + pr_debug("%pfwf: cycle: depends on %pfwf\n", sup_handle, + dev_link->supplier->fwnode); fw_devlink_relax_link(dev_link); dev_link->flags |= DL_FLAG_CYCLE; ret = true; @@ -2032,6 +2103,9 @@ static int fw_devlink_create_devlink(struct device *con, int ret = 0; u32 flags; + if (link->flags & FWLINK_FLAG_IGNORE) + return 0; + if (con->fwnode == link->consumer) flags = fw_devlink_get_flags(link->flags); else @@ -2058,13 +2132,19 @@ static int fw_devlink_create_devlink(struct device *con, /* * SYNC_STATE_ONLY device links don't block probing and supports cycles. - * So cycle detection isn't necessary and shouldn't be done. + * So, one might expect that cycle detection isn't necessary for them. + * However, if the device link was marked as SYNC_STATE_ONLY because + * it's part of a cycle, then we still need to do cycle detection. This + * is because the consumer and supplier might be part of multiple cycles + * and we need to detect all those cycles. */ - if (!(flags & DL_FLAG_SYNC_STATE_ONLY)) { + if (!device_link_flag_is_sync_state_only(flags) || + flags & DL_FLAG_CYCLE) { device_links_write_lock(); if (__fw_devlink_relax_cycles(con, sup_handle)) { __fwnode_link_cycle(link); flags = fw_devlink_get_flags(link->flags); + pr_debug("----- cycle: end -----\n"); dev_info(con, "Fixed dependency cycle(s) with %pfwf\n", sup_handle); } |