Re: [PATCH v4 2/5] remoteproc: Add device-managed variants of rproc_alloc/rproc_add

[Paul Cercueil <paul@crapouillou.net>]

Hi Fabien,


Le jeu., déc. 12, 2019 at 09:43, Fabien DESSENNE 
<fabien.dessenne@st.com> a écrit :
> Hi Paul,
> 
> 
> Good initiative! See me remarks below.
> 
> 
> On 10/12/2019 5:40 PM, Paul Cercueil wrote:
>>  Add API functions devm_rproc_alloc() and devm_rproc_add(), which 
>> behave
>>  like rproc_alloc() and rproc_add() respectively, but register their
>>  respective cleanup function to be called on driver detach.
>> 
>>  Signed-off-by: Paul Cercueil <paul@crapouillou.net>
>>  ---
>> 
>>  Notes:
>>       v3: New patch
>>       v4: No change
>> 
>>    drivers/remoteproc/remoteproc_core.c | 67 
>> ++++++++++++++++++++++++++++
>>    include/linux/remoteproc.h           |  5 +++
>>    2 files changed, 72 insertions(+)
>> 
>>  diff --git a/drivers/remoteproc/remoteproc_core.c 
>> b/drivers/remoteproc/remoteproc_core.c
>>  index 307df98347ba..0a9fc7fdd1c3 100644
>>  --- a/drivers/remoteproc/remoteproc_core.c
>>  +++ b/drivers/remoteproc/remoteproc_core.c
> 
> 
> Maybe these devm function shall be defined in a new 
> remoteproc/devres.c
> file. Although it seems to be a common usage I don't know if there is 
> a
> rule for that.

It's not a rule, more like a good practice. I'll do that.


> 
>>  @@ -1932,6 +1932,33 @@ int rproc_add(struct rproc *rproc)
>>    }
>>    EXPORT_SYMBOL(rproc_add);
>> 
>>  +static void devm_rproc_remove(void *rproc)
>>  +{
>>  +	rproc_del(rproc);
>>  +}
>>  +
>>  +/**
>>  + * devm_rproc_add() - resource managed rproc_add()
>>  + * @dev: the underlying device
>>  + * @rproc: the remote processor handle to register
>>  + *
>>  + * This function performs like rproc_add() but the registered 
>> rproc device will
>>  + * automatically be removed on driver detach.
>>  + *
>>  + * Returns 0 on success and an appropriate error code otherwise.
>>  + */
>>  +int devm_rproc_add(struct device *dev, struct rproc *rproc)
>>  +{
>>  +	int err;
>>  +
>>  +	err = rproc_add(rproc);
>>  +	if (err)
>>  +		return err;
>>  +
>>  +	return devm_add_action_or_reset(dev, devm_rproc_remove, rproc);
>>  +}
>>  +EXPORT_SYMBOL(devm_rproc_add);
>>  +
>>    /**
>>     * rproc_type_release() - release a remote processor instance
>>     * @dev: the rproc's device
>>  @@ -2149,6 +2176,46 @@ int rproc_del(struct rproc *rproc)
>>    }
>>    EXPORT_SYMBOL(rproc_del);
>> 
>>  +static void devm_rproc_free(struct device *dev, void *res)
>>  +{
>>  +	rproc_free(*(struct rproc **)res);
>>  +}
>>  +
>>  +/**
>>  + * devm_rproc_alloc() - resource managed rproc_alloc()
>>  + * @dev: the underlying device
>>  + * @name: name of this remote processor
>>  + * @ops: platform-specific handlers (mainly start/stop)
>>  + * @firmware: name of firmware file to load, can be NULL
>>  + * @len: length of private data needed by the rproc driver (in 
>> bytes)
>>  + *
>>  + * This function performs like rproc_alloc() but the acuired rproc 
>> device will
> 
> 
> typo: s/acuired/acquired
> 
> 
>>  + * automatically be released on driver detach.
>>  + *
>>  + * On success the new rproc is returned, and on failure, NULL.
>>  + */
>>  +struct rproc *devm_rproc_alloc(struct device *dev, const char 
>> *name,
>>  +			       const struct rproc_ops *ops,
>>  +			       const char *firmware, int len)
>>  +{
>>  +	struct rproc **ptr, *rproc;
>>  +
>>  +	ptr = devres_alloc(devm_rproc_free, sizeof(*ptr), GFP_KERNEL);
>>  +	if (!ptr)
>>  +		return ERR_PTR(-ENOMEM);
>>  +
>>  +	rproc = rproc_alloc(dev, name, ops, firmware, len);
>>  +	if (rproc) {
>>  +		*ptr = rproc;
>>  +		devres_add(dev, ptr);
>>  +	} else {
>>  +		devres_free(ptr);
>>  +	}
>>  +
>>  +	return rproc;
> 
> 
> Can't you use devm_add_action_or_reset() here too?

Yes, I guess that will make things simpler.

Thanks,
-Paul


> 
>>  +}
>>  +EXPORT_SYMBOL(devm_rproc_alloc);
>>  +
>>    /**
>>     * rproc_add_subdev() - add a subdevice to a remoteproc
>>     * @rproc: rproc handle to add the subdevice to
>>  diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
>>  index 16ad66683ad0..5f201f0c86c3 100644
>>  --- a/include/linux/remoteproc.h
>>  +++ b/include/linux/remoteproc.h
>>  @@ -595,6 +595,11 @@ int rproc_add(struct rproc *rproc);
>>    int rproc_del(struct rproc *rproc);
>>    void rproc_free(struct rproc *rproc);
>> 
>>  +struct rproc *devm_rproc_alloc(struct device *dev, const char 
>> *name,
>>  +			       const struct rproc_ops *ops,
>>  +			       const char *firmware, int len);
>>  +int devm_rproc_add(struct device *dev, struct rproc *rproc);
>>  +
>>    void rproc_add_carveout(struct rproc *rproc, struct 
>> rproc_mem_entry *mem);
>> 
>>    struct rproc_mem_entry *
> 
> 
> BR
> 
> Fabien