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

Bartosz Golaszewski
2018-03-23T13:46:25Z

2018-03-23 14:43 GMT+01:00 Philipp Zabel <p.zabel@pengutronix.de>:
> 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

Oops, thanks for spotting that.

Thanks,
Bart