Re: [PATCH v4 1/8] reset: modify the way reset lookup works for board files

Philipp Zabel
2018-03-23T13:43:52Z

On Fri, 2018-03-23 at 14:04 +0100, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
>
> Commit 7af1bb19f1d7 ("reset: add support for non-DT systems")
> introduced reset control lookup mechanism for boards that still use
> board files.
>
> The routine used to register lookup entries takes the corresponding
> reset_controlled_dev structure as argument.
>
> It's been determined however that for the first user of this new
> interface - davinci psc driver - it will be easier to register the
> lookup entries using the reset controller device name.
>
> This patch changes the way lookup entries are added.
>
> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> ---
> drivers/reset/core.c | 38 +++++++++++++++++++++++++++++++-------
> include/linux/reset-controller.h | 14 ++++++++------
> 2 files changed, 39 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/reset/core.c b/drivers/reset/core.c
> index 06fa4907afc4..f4a29c046995 100644
> --- a/drivers/reset/core.c
> +++ b/drivers/reset/core.c
> @@ -153,12 +153,10 @@ EXPORT_SYMBOL_GPL(devm_reset_controller_register);
>
> /**
> * reset_controller_add_lookup - register a set of lookup entries
> - * @rcdev: initialized reset controller device owning the reset line
> * @lookup: array of reset lookup entries
> * @num_entries: number of entries in the lookup array
> */
> -void reset_controller_add_lookup(struct reset_controller_dev *rcdev,
> - struct reset_control_lookup *lookup,
> +void reset_controller_add_lookup(struct reset_control_lookup *lookup,
> unsigned int num_entries)
> {
> struct reset_control_lookup *entry;
> @@ -168,13 +166,12 @@ void reset_controller_add_lookup(struct reset_controller_dev *rcdev,
> for (i = 0; i < num_entries; i++) {
> entry = &lookup[i];
>
> - if (!entry->dev_id) {
> - pr_warn("%s(): reset lookup entry has no dev_id, skipping\n",
> + if (!entry->dev_id || !entry->provider) {
> + pr_warn("%s(): reset lookup entry badly specified, skipping\n",
> __func__);
> continue;
> }
>
> - entry->rcdev = rcdev;
> list_add_tail(&entry->list, &reset_lookup_list);
> }
> mutex_unlock(&reset_lookup_mutex);
> @@ -526,11 +523,30 @@ struct reset_control *__of_reset_control_get(struct device_node *node,
> }
> EXPORT_SYMBOL_GPL(__of_reset_control_get);
>
> +static struct reset_controller_dev *
> +__reset_controller_by_name(const char *name)
> +{
> + struct reset_controller_dev *rcdev;
> +
> + lockdep_assert_held(&reset_list_mutex);
> +
> + list_for_each_entry(rcdev, &reset_controller_list, list) {
> + if (!rcdev->dev)
> + continue;
> +
> + if (!strcmp(name, dev_name(rcdev->dev)))
> + return rcdev;
> + }
> +
> + return NULL;
> +}
> +
> static struct reset_control *
> __reset_control_get_from_lookup(struct device *dev, const char *con_id,
> bool shared, bool optional)
> {
> const struct reset_control_lookup *lookup;
> + struct reset_controller_dev *rcdev;
> const char *dev_id = dev_name(dev);
> struct reset_control *rstc = NULL;
>
> @@ -547,7 +563,15 @@ __reset_control_get_from_lookup(struct device *dev, const char *con_id,
> ((con_id && lookup->con_id) &&
> !strcmp(con_id, lookup->con_id))) {
> mutex_lock(&reset_list_mutex);
> - rstc = __reset_control_get_internal(lookup->rcdev,
> + rcdev = __reset_controller_by_name(lookup->provider);
> + if (!rcdev) {
> + mutex_unlock(&reset_list_mutex);
> + mutex_unlock(&reset_lookup_mutex);
> + /* Reset provider may not be ready yet. */
> + return -EPROBE_DEFER;

Thanks, I've applied this patch to reset/next with the following change:

-                               return -EPROBE_DEFER;
+                               return ERR_PTR(-EPROBE_DEFER);

regards
Philipp