Re: [PATCH v3 2/3] i3c: master: Add Qualcomm I3C controller driver
From: Krzysztof Kozlowski
Date: Wed Apr 09 2025 - 02:10:50 EST
On 09/04/2025 07:48, Mukesh Kumar Savaliya wrote:
> Hi Krzysztof,
>
> On 4/9/2025 12:11 AM, Krzysztof Kozlowski wrote:
>> On 08/04/2025 15:23, Mukesh Kumar Savaliya wrote:
>>>>> +
>>>>> +static int i3c_geni_runtime_get_mutex_lock(struct geni_i3c_dev *gi3c)
>>>>> +{
>>>>
>>>> You miss sparse/lockdep annotations.
>>>>
>>> This is called in pair only, but to avoid repeated code in caller
>>> functions, we have designed this wrapper.
>>> i3c_geni_runtime_get_mutex_lock()
>>> i3c_geni_runtime_put_mutex_unlock().
>>>
>>> caller function maintains the parity. e.g. geni_i3c_master_priv_xfers().
>>>
>>> Does a comment help here ? Then i can write up to add.
>>
>> I do not see how this is relevant to my comment at all.
>>
> What i understood is you suspect about lock/unlock imbalance right ?
> I know that Lockdep annotations will be used to check if locks are
> acquired and released in a proper order.
>
> You want me to add below code in both the functions mentioned ?
> lockdep_assert_held(&gi3c->lock);
>
> What exact sparse/attribute can be added ? I am not sure about that.
I don't think you tried enough.
git grep sparse -- Documentation/
which gives you the file name, so:
git grep lock -- Documentation/dev-tools/sparse.rst
Use sparse instead of lockdep.
>>>
>>>>> + int ret;
>>>>> +
>>>>> + mutex_lock(&gi3c->lock);
>>>>> + reinit_completion(&gi3c->done);
>>>>> + ret = pm_runtime_get_sync(gi3c->se.dev);
>>>>> + if (ret < 0) {
>>>>> + dev_err(gi3c->se.dev, "error turning on SE resources:%d\n", ret);
>>>>> + pm_runtime_put_noidle(gi3c->se.dev);
>>>>> + /* Set device in suspended since resume failed */
>>>>> + pm_runtime_set_suspended(gi3c->se.dev);
>>>>> + mutex_unlock(&gi3c->lock);
>>>>
>>>> Either you lock or don't lock, don't mix these up.
>>>>
>>> Caller is taking care of not calling i3c_geni_runtime_put_mutex_unlock()
>>> if this failed.
>>
>>
>> I do not see how this is relevant to my comment at all.
>>
> same as above
>>>>> + return ret;
>>>>> + }
>>>>> +
>>>>> + return 0;
>>>>> +}
>>>>> +
>>>>> +static void i3c_geni_runtime_put_mutex_unlock(struct geni_i3c_dev *gi3c)
>>>>> +{
>>>>
>>>> Missing annotations.
>>>>
>>> Shall i add a comment here ?
>>
>> Do you understand what is sparse? And lockdep?
>>
> Little but not clear on exact sparse attribute to be added. please help
> me. if you can help with some clear comment and sample, will be easier
> if you can.
You did not even bother to grep for simple term.
Best regards,
Krzysztof