On 10/19/21 12:32 PM, Cezary Rojewski wrote: > On 2021-10-19 6:58 PM, Pierre-Louis Bossart wrote: >>>> hmm. It's not clear whether we should initialize the regular hdac_bus >>>> fields in the ext_bus_init(). For plain HDA, these are also initialized >>>> in the caller. E.g. in sound/pci/hda/hda_controller.c. >>>> >>>> So if we start cleaning up, should we go further put this in >>>> snd_hdac_bus_init()? >>>> >>>> Then another is what is the right place for settings like "sync_write = >>>> 1". While this settings applies to all current users of the extended >>>> bus, this is really hw specific setting and not really a property of >>>> the extended bus, so this feels a bit out-of-place. >>> >>> I'm rather in favor of bigger cleanups. We can definitely move further >>> in the future : ) >> >> I am not opposed to updates in this hdaudio-ext part, but I am in favor >> of less ambitious step-by-step changes. >> >> a) This is legacy code where the initial authors have moved on, and it's >> very hard to figure out what the intent was. It's quite common to have >> discussion on feature v. bug, see e.g. the discussion we had on this in >> https://github.com/thesofproject/linux/pull/3175#pullrequestreview-772674119 >> >> >> b) In addition, this code is shared between two teams with separate >> testing/CI capabilities and limited number of commercial/shipping >> devices. There is a very large risk of introducing bugs even with the >> best intentions. >> >> Before we do any changes in functionality, there are already basic steps >> that can be done, e.g. using consistent naming between variables, the >> existing code is just confusing as can be: >> >> struct hdac_stream *stream; >> struct hdac_ext_stream *stream; >> struct hdac_stream *hstream; >> struct hdac_ext_stream *hstream; >> >> I started basic cleanups here: >> https://github.com/thesofproject/linux/pull/3158, I haven't had time to >> complete this because of more important locking issues, but I intend to >> send those clarifications for the next cycle. >> >> Again before we do large changes let's think of smaller steps and how we >> are going to validate those changes. > > Agree, step-by-step is the way to go. > > Isn't this patch a 'step' though? This isn't remotely a refactor, just > gathering of common parts of ext-bus initialization. We could start with > this so legacy users are unaffected, then have snd_hdac_bus_init() > updated so snd_hdac_ext_bus_init() is devoid of 'core' fields > assignments as suggested by Kai. If it was just moving common parts, I would have no issue. My main objection is that you went one step further and started renaming stuff in rather confusing ways, e.g. -void sof_hda_bus_init(struct hdac_bus *bus, struct device *dev) +void sof_hda_bus_init(struct hda_bus *bus, struct pci_dev *pdev, - * snd_hdac_ext_bus_init - initialize a HD-audio extended bus + * snd_hda_ext_bus_init - initialize a HD-audio extended bus hda_bus is a definition from hda_codec.h, I don't see a reason why we should use this structure when the vast majority of the code uses hdac_bus. And the purpose of hdac_ext is really to deal with *controller* extensions to couple/decouple DMAs. There is no dependency on codecs at that level. Even if there was, I also don't really see why/when we should start using hda_ext v. hdac_ext, the naming convention completely escapes me. It would seem logical to me to only use hdac_ext as an extension of hdac_, no? I also don't get what this means: + snd_hda_ext_bus_init(hbus, pci, NULL, ext_ops, "sklbus"); what is 'sklbus' and what purpose are you trying to accomplish with this change?
