On 4-1-2017 22:19, Rafał Miłecki wrote: > On 4 January 2017 at 21:07, Arend Van Spriel > <arend.vanspriel@xxxxxxxxxxxx> wrote: >> On 4-1-2017 18:58, Rafał Miłecki wrote: >>> From: Rafał Miłecki <rafal@xxxxxxxxxx> >>> >>> There are some devices (e.g. Netgear R8000 home router) with one chipset >>> model used for different radios, some of them limited to subbands. NVRAM >>> entries don't contain any extra info on such limitations and firmware >>> reports full list of channels to us. We need to store extra limitation >>> info in DT to support such devices properly. >>> >>> Now there is a cfg80211 helper for reading such info use it in brcmfmac. >>> This patch adds check for channel being disabled with orig_flags which >>> is how this wiphy helper and wiphy_register work. >>> >>> Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx> >>> --- >>> This patch should probably go through wireless-driver-next which is why >>> it got weird number 4/3. I'm sending it just as a proof of concept. >>> It was succesfully tested on SmartRG SR400ac with BCM43602. >>> >>> V4: Respect IEEE80211_CHAN_DISABLED in orig_flags >>> V5: Update commit message >>> V6: Call wiphy_read_of_freq_limits after brcmf_setup_wiphybands to make it work >>> with helper setting "flags" instead of "orig_flags". >>> --- >>> drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 9 ++++++++- >>> 1 file changed, 8 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c >>> index ccae3bb..a008ba5 100644 >>> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c >>> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c >>> @@ -5886,6 +5886,9 @@ static int brcmf_construct_chaninfo(struct brcmf_cfg80211_info *cfg, >>> band->band); >>> channel[index].hw_value = ch.control_ch_num; >>> >>> + if (channel->orig_flags & IEEE80211_CHAN_DISABLED) >>> + continue; >>> + >> >> So to be clear this is still needed for subsequent calls to >> brcmf_setup_wiphybands(). The subsequent calls are done from the >> regulatory notifier. So I think we have an issue with this approach. Say >> the device comes up with US. That would set DISABLED flags for channels >> 12 to 14. With a country update to PL we would want to enable channels >> 12 and 13, right? The orig_flags are copied from the initial flags >> during wiphy_register() so it seems we will skip enabling 12 and 13. I >> think we should remove the check above and call >> wiphy_read_of_freq_limits() as a last step within >> brcmf_setup_wiphybands(). It means it is called every time, but it >> safeguards that the limits in DT are always applied. > > I'm not exactly happy with channels management in brcmfmac. Before > calling wiphy_register it already disables channels unavailable for > current country. This results in setting IEEE80211_CHAN_DISABLED in What do you mean by current country. There is none that we are aware off in the driver. So we obtain the channels for the current country/revision in the firmware and enable those before wiphy_register(). This all is within the probe/init sequence so I do not really see an issue. As the wiphy object is not yet registered there is no user-space awareness > orig_flags of channels that may become available later, after country > change. Please note it happens even right now, without this patch. Nope. As stated earlier the country setting in firmware is not updated unless you provide a *proper* mapping of user-space country code to firmware country code/revision. That is the reason, ie. firmware simply returns the same list of channels as nothing changed from its perspective. We may actually drop 11d support. > Maybe you can workaround this by ignoring orig_flags in custom > regulatory code, but I'd just prefer to have it nicely handled in the > first place. Please care to explain your ideas before putting any effort in this "feature". As the author of the code that makes you unhappy and as driver maintainer I would like to get a clearer picture of your point of view. What exactly is the issue that makes you unhappy. > This is the next feature I'm going to work on. AFAIU this patch won't > be applied for now (it's for wireless-drivers-next and we first need > to get wiphy_read_of_freq_limits in that tree). By the time that > happens I may have another patchset cleaning brcmfmac ready. And FWIW > this patch wouldn't make things worse *at this point* as we don't > really support country switching for any device yet. Now who is *we*? We as Broadcom can, because we know how to map the ISO 3166-1 country code to firmware country code/revision for a specific firmware release. Firmware uses its own regulatory rules which may differ from what regdb has. Now I know Intel submitted a mechanism to export firmware rules to regdb so maybe we should consider switching to that api if that has been upstreamed. Need to check. > So I hope problem with channels in brcmfmac doesn't mean we need to > postpone patches 1-3. I do not see any reason to postpone. Regards, Arend -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
