Re: [PATCH 4/5] soundwire: qcom: avoid dependency on CONFIG_SLIMBUS

Jonathan Marek
2020-06-09T11:32:58Z

On 6/9/20 5:52 AM, Srinivas Kandagatla wrote:
>
>
> On 08/06/2020 21:43, Jonathan Marek wrote:
>> The driver may be used without slimbus, so don't depend on slimbus.
>>
>> Signed-off-by: Jonathan Marek <jonathan@marek.ca>
>> ---
>>   drivers/soundwire/Kconfig | 1 -
>>   drivers/soundwire/qcom.c  | 5 +++++
>>   2 files changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/soundwire/Kconfig b/drivers/soundwire/Kconfig
>> index fa2b4ab92ed9..d121cf739090 100644
>> --- a/drivers/soundwire/Kconfig
>> +++ b/drivers/soundwire/Kconfig
>> @@ -33,7 +33,6 @@ config SOUNDWIRE_INTEL
>>   config SOUNDWIRE_QCOM
>>       tristate "Qualcomm SoundWire Master driver"
>> -    depends on SLIMBUS
>>       depends on SND_SOC
>
> Why not move this to imply SLIMBUS this will give more flexibility!
>
>

If you mean to change it to "select SLIMBUS", I'd prefer not to, because
this would increase code size unnecessarily in my kernel.

>>       help
>>         SoundWire Qualcomm Master driver.
>> diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c
>> index 14334442615f..ac81c64768ea 100644
>> --- a/drivers/soundwire/qcom.c
>> +++ b/drivers/soundwire/qcom.c
>> @@ -769,13 +769,18 @@ static int qcom_swrm_probe(struct
>> platform_device *pdev)
>>       if (!ctrl)
>>           return -ENOMEM;
>> +#ifdef CONFIG_SLIMBUS
>>       if (dev->parent->bus == &slimbus_bus) {
>> +#else
>> +    if (false) {
>> +#endif
>
> May be you can do bit more cleanup here, which could endup like:
>
>
> ctrl->regmap = dev_get_regmap(dev->parent, NULL);
> if (!ctrl->regmap) {
>     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>     if (res) {
>         ctrl->mmio = devm_ioremap_resource(dev, res);
>         if (IS_ERR(ctrl->mmio)) {
>             dev_err(dev, "No valid mem resource found\n");
>             return PTR_ERR(ctrl->mmio);
>         }
>
>         ctrl->reg_read = qcom_swrm_cpu_reg_read;
>         ctrl->reg_write = qcom_swrm_cpu_reg_write;
>     } else {
>         dev_err(dev, "No valid slim resource found\n");
>         return -EINVAL;
>     }
> } else {
>     ctrl->reg_read = qcom_swrm_ahb_reg_read;
>     ctrl->reg_write = qcom_swrm_ahb_reg_write;
> }
>
>
>
> thanks,
> srini

I don't think this is better, it feels more obfuscated, and I think its
possible we may end up with the mmio sdw having a parent with a regmap.
(it is not how I did things up in my upstream stack, but in downstream
the sdw nodes are inside the "macro" codec nodes)

I understand the '#ifdef CONFIG_SLIMBUS'/'dev->parent->bus ==
&slimbus_bus' is ugly, but at least its clear what's going on. Unless
you have a better suggestion?

>>           ctrl->reg_read = qcom_swrm_ahb_reg_read;
>>           ctrl->reg_write = qcom_swrm_ahb_reg_write;
>>           ctrl->regmap = dev_get_regmap(dev->parent, NULL);
>>           if (!ctrl->regmap)
>>               return -EINVAL;
>>       } else {
>> +
>>           res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>           ctrl->reg_read = qcom_swrm_cpu_reg_read;
>>