Message-ID: <920f0b73-238e-8923-2344-98ac5cc96d7d@linaro.org>
Date:   Thu, 9 Feb 2023 15:49:46 +0000
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Subject: Re: [PATCH 2/5] soundwire: qcom: enable runtime pm before controller
 is registered
Content-Language: en-US
To:     Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
        vkoul@kernel.org
Cc:     yung-chuan.liao@linux.intel.com, alsa-devel@alsa-project.org,
        linux-kernel@vger.kernel.org, steev@kali.org,
        johan+linaro@kernel.org, quic_bjorande@quicinc.com
References: <20230209131336.18252-1-srinivas.kandagatla@linaro.org>
 <20230209131336.18252-3-srinivas.kandagatla@linaro.org>
 <92a2560a-74cd-aa13-fea6-7619e355b26e@linux.intel.com>
From:   Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
In-Reply-To: <92a2560a-74cd-aa13-fea6-7619e355b26e@linux.intel.com>
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Precedence: bulk


On 09/02/2023 15:21, Pierre-Louis Bossart wrote:
> 
> 
> On 2/9/23 07:13, Srinivas Kandagatla wrote:
>> Registering controller even before pm runtime is enabled will result
>> in pm runtime underflow warnings. Fix this by properly moving
>> the runtime pm enable before registering controller.
> 
> That seems very odd. The Intel code configures the pm_runtime stuff
> *after* the call to sdw_bus_master_add(), and we've not seen any
> underflow warnings? We even configure pm_runtime after starting the bus.
> Likewise for peripherals the pm_runtime part is enabled after the device
> is initialized.
> 
This was very random during bootup, Let me see if I can collect a back 
trace after reverting this patch..

--srini

> Not following the problem and suggested solution.
> 
>> Fixes: 74e79da9fd46 ("soundwire: qcom: add runtime pm support")
>> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
>> ---
>>   drivers/soundwire/qcom.c | 12 ++++++------
>>   1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
>> index 9d8ae77bad0a..b2363839624c 100644
>> --- a/drivers/soundwire/qcom.c
>> +++ b/drivers/soundwire/qcom.c
>> @@ -1417,6 +1417,12 @@ static int qcom_swrm_probe(struct platform_device *pdev)
>>   		}
>>   	}
>>   
>> +	pm_runtime_set_autosuspend_delay(dev, 3000);
>> +	pm_runtime_use_autosuspend(dev);
>> +	pm_runtime_mark_last_busy(dev);
>> +	pm_runtime_set_active(dev);
>> +	pm_runtime_enable(dev);
>> +
>>   	ret = sdw_bus_master_add(&ctrl->bus, dev, dev->fwnode);
>>   	if (ret) {
>>   		dev_err(dev, "Failed to register Soundwire controller (%d)\n",
>> @@ -1435,12 +1441,6 @@ static int qcom_swrm_probe(struct platform_device *pdev)
>>   		 (ctrl->version >> 24) & 0xff, (ctrl->version >> 16) & 0xff,
>>   		 ctrl->version & 0xffff);
>>   
>> -	pm_runtime_set_autosuspend_delay(dev, 3000);
>> -	pm_runtime_use_autosuspend(dev);
>> -	pm_runtime_mark_last_busy(dev);
>> -	pm_runtime_set_active(dev);
>> -	pm_runtime_enable(dev);
>> -
>>   	/* Clk stop is not supported on WSA Soundwire masters */
>>   	if (ctrl->version <= 0x01030000) {
>>   		ctrl->clock_stop_not_supported = true;