[PATCH] soundwire: qcom: adjust autoenumeration timeout

[PATCH] soundwire: qcom: adjust autoenumeration timeout

[Srinivas Kandagatla]

Currently timeout for autoenumeration during probe and bus reset is set to
2 secs which is really a big value. This can have an adverse effect on
boot time if the slave device is not ready/reset.
This was the case with wcd938x which was not reset yet but we spent 2
secs waiting in the soundwire controller probe. Reduce this time to
1/10 of Hz which should be good enough time to finish autoenumeration
if any slaves are available on the bus.

Reported-by: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
---
 drivers/soundwire/qcom.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
index da1ad7ebb1aa..432e5cb9a4d2 100644
--- a/drivers/soundwire/qcom.c
+++ b/drivers/soundwire/qcom.c
@@ -105,7 +105,7 @@
 
 #define SWRM_SPECIAL_CMD_ID	0xF
 #define MAX_FREQ_NUM		1
-#define TIMEOUT_MS		(2 * HZ)
+#define TIMEOUT_MS		(HZ/10)
 #define QCOM_SWRM_MAX_RD_LEN	0x1
 #define QCOM_SDW_MAX_PORTS	14
 #define DEFAULT_CLK_FREQ	9600000
-- 
2.21.0

Re: [PATCH] soundwire: qcom: adjust autoenumeration timeout

[Pierre-Louis Bossart]

On 4/29/22 11:09, Srinivas Kandagatla wrote:
> Currently timeout for autoenumeration during probe and bus reset is set to
> 2 secs which is really a big value. This can have an adverse effect on
> boot time if the slave device is not ready/reset.
> This was the case with wcd938x which was not reset yet but we spent 2
> secs waiting in the soundwire controller probe. Reduce this time to
> 1/10 of Hz which should be good enough time to finish autoenumeration
> if any slaves are available on the bus.

Can I ask why this is dependent on a software configuration you have no control on?

Why not simply:

#define TIMEOUT_MS		100

?

> 
> Reported-by: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
> ---
>  drivers/soundwire/qcom.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
> index da1ad7ebb1aa..432e5cb9a4d2 100644
> --- a/drivers/soundwire/qcom.c
> +++ b/drivers/soundwire/qcom.c
> @@ -105,7 +105,7 @@
>  
>  #define SWRM_SPECIAL_CMD_ID	0xF
>  #define MAX_FREQ_NUM		1
> -#define TIMEOUT_MS		(2 * HZ)
> +#define TIMEOUT_MS		(HZ/10)
>  #define QCOM_SWRM_MAX_RD_LEN	0x1
>  #define QCOM_SDW_MAX_PORTS	14
>  #define DEFAULT_CLK_FREQ	9600000

Re: [PATCH] soundwire: qcom: adjust autoenumeration timeout

[Srinivas Kandagatla]

On 29/04/2022 17:19, Pierre-Louis Bossart wrote:
> 
> 
> On 4/29/22 11:09, Srinivas Kandagatla wrote:
>> Currently timeout for autoenumeration during probe and bus reset is set to
>> 2 secs which is really a big value. This can have an adverse effect on
>> boot time if the slave device is not ready/reset.
>> This was the case with wcd938x which was not reset yet but we spent 2
>> secs waiting in the soundwire controller probe. Reduce this time to
>> 1/10 of Hz which should be good enough time to finish autoenumeration
>> if any slaves are available on the bus.
> 
> Can I ask why this is dependent on a software configuration you have no control on?
> 
> Why not simply:
> 
> #define TIMEOUT_MS		100
> 
> ?

That will work too.

--srini


> 
>>
>> Reported-by: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
>> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
>> ---
>>   drivers/soundwire/qcom.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
>> index da1ad7ebb1aa..432e5cb9a4d2 100644
>> --- a/drivers/soundwire/qcom.c
>> +++ b/drivers/soundwire/qcom.c
>> @@ -105,7 +105,7 @@
>>   
>>   #define SWRM_SPECIAL_CMD_ID	0xF
>>   #define MAX_FREQ_NUM		1
>> -#define TIMEOUT_MS		(2 * HZ)
>> +#define TIMEOUT_MS		(HZ/10)
>>   #define QCOM_SWRM_MAX_RD_LEN	0x1
>>   #define QCOM_SDW_MAX_PORTS	14
>>   #define DEFAULT_CLK_FREQ	9600000