| Message ID | 20170103110340.23249-2-zajec5@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Johannes Berg |
| Headers | show |
On 3-1-2017 12:03, Rafał Miłecki wrote: > From: Rafał Miłecki <rafal@milecki.pl> > > This patch adds a helper for reading that new property and applying > limitations or supported channels specified this way. > It may be useful for specifying single band devices or devices that > support only some part of the whole band. It's common that tri-band > routers have separated radios for lower and higher part of 5 GHz band. > > Signed-off-by: Rafał Miłecki <rafal@milecki.pl> > --- > V2: Put main code in core.c as it isn't strictly part of regulatory - pointed > by Arend. > Update to support ieee80211-freq-limit (new property). > V3: Introduce separated wiphy_read_of_freq_limits function. > Add extra sanity checks for DT data. > Move code back to reg.c as suggested by Johannes. > V4: Move code to of.c > Use one helper called at init time (no runtime hooks) > Modify orig_flags > --- > include/net/cfg80211.h | 26 ++++++++++ > net/wireless/Makefile | 1 + > net/wireless/of.c | 137 +++++++++++++++++++++++++++++++++++++++++++++++++ > net/wireless/reg.c | 4 +- > net/wireless/reg.h | 2 + > 5 files changed, 168 insertions(+), 2 deletions(-) > create mode 100644 net/wireless/of.c > > diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h > index ca2ac1c..d7723a8 100644 > --- a/include/net/cfg80211.h > +++ b/include/net/cfg80211.h > @@ -311,6 +311,32 @@ struct ieee80211_supported_band { > struct ieee80211_sta_vht_cap vht_cap; > }; > > +/** > + * wiphy_read_of_freq_limits - read frequency limits from device tree > + * > + * @wiphy: the wireless device to get extra limits for > + * > + * Some devices may have extra limitations specified in DT. This may be useful > + * for chipsets that normally support more bands but are limited due to board > + * design (e.g. by antennas or extermal power amplifier). > + * > + * This function reads info from DT and uses it to *modify* channels (disable > + * unavailable ones). It's usually a *bad* idea to use it in drivers with > + * shared channel data as DT limitations are device specific. > + * > + * As this function access device node it has to be called after set_wiphy_dev. You are aware that you need to modify this description with earlier patch "cfg80211: allow passing struct device in the wiphy_new call", right? :-p > + * It also modifies channels so they have to be set first. > + */ > +#ifdef CONFIG_OF > +int wiphy_read_of_freq_limits(struct wiphy *wiphy); > +#else /* CONFIG_OF */ > +static inline int wiphy_read_of_freq_limits(struct wiphy *wiphy) > +{ > + return 0; > +} > +#endif /* !CONFIG_OF */ > + > + [...] > diff --git a/net/wireless/reg.c b/net/wireless/reg.c > index 5dbac37..bda0e9e 100644 > --- a/net/wireless/reg.c > +++ b/net/wireless/reg.c > @@ -748,8 +748,8 @@ static bool is_valid_rd(const struct ieee80211_regdomain *rd) > return true; > } > > -static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range, > - u32 center_freq_khz, u32 bw_khz) > +bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range, > + u32 center_freq_khz, u32 bw_khz) > { > u32 start_freq_khz, end_freq_khz; would it be more appropriate to move this function to util.c? Regards, Arend
On 3 January 2017 at 13:10, Arend Van Spriel <arend.vanspriel@broadcom.com> wrote: > On 3-1-2017 12:03, Rafał Miłecki wrote: >> From: Rafał Miłecki <rafal@milecki.pl> >> >> This patch adds a helper for reading that new property and applying >> limitations or supported channels specified this way. >> It may be useful for specifying single band devices or devices that >> support only some part of the whole band. It's common that tri-band >> routers have separated radios for lower and higher part of 5 GHz band. >> >> Signed-off-by: Rafał Miłecki <rafal@milecki.pl> >> --- >> V2: Put main code in core.c as it isn't strictly part of regulatory - pointed >> by Arend. >> Update to support ieee80211-freq-limit (new property). >> V3: Introduce separated wiphy_read_of_freq_limits function. >> Add extra sanity checks for DT data. >> Move code back to reg.c as suggested by Johannes. >> V4: Move code to of.c >> Use one helper called at init time (no runtime hooks) >> Modify orig_flags >> --- >> include/net/cfg80211.h | 26 ++++++++++ >> net/wireless/Makefile | 1 + >> net/wireless/of.c | 137 +++++++++++++++++++++++++++++++++++++++++++++++++ >> net/wireless/reg.c | 4 +- >> net/wireless/reg.h | 2 + >> 5 files changed, 168 insertions(+), 2 deletions(-) >> create mode 100644 net/wireless/of.c >> >> diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h >> index ca2ac1c..d7723a8 100644 >> --- a/include/net/cfg80211.h >> +++ b/include/net/cfg80211.h >> @@ -311,6 +311,32 @@ struct ieee80211_supported_band { >> struct ieee80211_sta_vht_cap vht_cap; >> }; >> >> +/** >> + * wiphy_read_of_freq_limits - read frequency limits from device tree >> + * >> + * @wiphy: the wireless device to get extra limits for >> + * >> + * Some devices may have extra limitations specified in DT. This may be useful >> + * for chipsets that normally support more bands but are limited due to board >> + * design (e.g. by antennas or extermal power amplifier). >> + * >> + * This function reads info from DT and uses it to *modify* channels (disable >> + * unavailable ones). It's usually a *bad* idea to use it in drivers with >> + * shared channel data as DT limitations are device specific. >> + * >> + * As this function access device node it has to be called after set_wiphy_dev. > > You are aware that you need to modify this description with earlier > patch "cfg80211: allow passing struct device in the wiphy_new call", > right? :-p I dropped that earlier patch for now as it's no longer a requirement for this change. If someone find is useful though, I'll be happy to resume my work on it later. And update this documentation as you pointed out ;) >> + * It also modifies channels so they have to be set first. >> + */ >> +#ifdef CONFIG_OF >> +int wiphy_read_of_freq_limits(struct wiphy *wiphy); >> +#else /* CONFIG_OF */ >> +static inline int wiphy_read_of_freq_limits(struct wiphy *wiphy) >> +{ >> + return 0; >> +} >> +#endif /* !CONFIG_OF */ >> + >> + > > [...] > >> diff --git a/net/wireless/reg.c b/net/wireless/reg.c >> index 5dbac37..bda0e9e 100644 >> --- a/net/wireless/reg.c >> +++ b/net/wireless/reg.c >> @@ -748,8 +748,8 @@ static bool is_valid_rd(const struct ieee80211_regdomain *rd) >> return true; >> } >> >> -static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range, >> - u32 center_freq_khz, u32 bw_khz) >> +bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range, >> + u32 center_freq_khz, u32 bw_khz) >> { >> u32 start_freq_khz, end_freq_khz; > > would it be more appropriate to move this function to util.c? I'm OK with moving this function (and maybe struct ieee80211_freq_range as well). Any objections?
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index ca2ac1c..d7723a8 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -311,6 +311,32 @@ struct ieee80211_supported_band { struct ieee80211_sta_vht_cap vht_cap; }; +/** + * wiphy_read_of_freq_limits - read frequency limits from device tree + * + * @wiphy: the wireless device to get extra limits for + * + * Some devices may have extra limitations specified in DT. This may be useful + * for chipsets that normally support more bands but are limited due to board + * design (e.g. by antennas or extermal power amplifier). + * + * This function reads info from DT and uses it to *modify* channels (disable + * unavailable ones). It's usually a *bad* idea to use it in drivers with + * shared channel data as DT limitations are device specific. + * + * As this function access device node it has to be called after set_wiphy_dev. + * It also modifies channels so they have to be set first. + */ +#ifdef CONFIG_OF +int wiphy_read_of_freq_limits(struct wiphy *wiphy); +#else /* CONFIG_OF */ +static inline int wiphy_read_of_freq_limits(struct wiphy *wiphy) +{ + return 0; +} +#endif /* !CONFIG_OF */ + + /* * Wireless hardware/device configuration structures and methods */ diff --git a/net/wireless/Makefile b/net/wireless/Makefile index 4c9e39f..95b4c09 100644 --- a/net/wireless/Makefile +++ b/net/wireless/Makefile @@ -11,6 +11,7 @@ obj-$(CONFIG_WEXT_PRIV) += wext-priv.o cfg80211-y += core.o sysfs.o radiotap.o util.o reg.o scan.o nl80211.o cfg80211-y += mlme.o ibss.o sme.o chan.o ethtool.o mesh.o ap.o trace.o ocb.o +cfg80211-$(CONFIG_OF) += of.o cfg80211-$(CONFIG_CFG80211_DEBUGFS) += debugfs.o cfg80211-$(CONFIG_CFG80211_WEXT) += wext-compat.o wext-sme.o cfg80211-$(CONFIG_CFG80211_INTERNAL_REGDB) += regdb.o diff --git a/net/wireless/of.c b/net/wireless/of.c new file mode 100644 index 0000000..d5791c8 --- /dev/null +++ b/net/wireless/of.c @@ -0,0 +1,137 @@ +/* + * Copyright (C) 2017 Rafał Miłecki <rafal@milecki.pl> + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include <linux/of.h> +#include <net/cfg80211.h> +#include "reg.h" + +static bool wiphy_freq_limits_valid_chan(struct wiphy *wiphy, + struct ieee80211_freq_range *freq_limits, + unsigned int n_freq_limits, + struct ieee80211_channel *chan) +{ + u32 bw = MHZ_TO_KHZ(20); + int i; + + for (i = 0; i < n_freq_limits; i++) { + struct ieee80211_freq_range *limit = &freq_limits[i]; + + if (reg_does_bw_fit(limit, MHZ_TO_KHZ(chan->center_freq), bw)) + return true; + } + + return false; +} + +static void wiphy_freq_limits_apply(struct wiphy *wiphy, + struct ieee80211_freq_range *freq_limits, + unsigned int n_freq_limits) +{ + enum nl80211_band band; + int i; + + if (WARN_ON(!n_freq_limits)) + return; + + for (band = 0; band < NUM_NL80211_BANDS; band++) { + struct ieee80211_supported_band *sband = wiphy->bands[band]; + + if (!sband) + continue; + + for (i = 0; i < sband->n_channels; i++) { + struct ieee80211_channel *chan = &sband->channels[i]; + + if (chan->orig_flags & IEEE80211_CHAN_DISABLED) + continue; + + if (!wiphy_freq_limits_valid_chan(wiphy, freq_limits, + n_freq_limits, + chan)) { + pr_debug("Disabling freq %d MHz as it's out of OF limits\n", + chan->center_freq); + chan->orig_flags |= IEEE80211_CHAN_DISABLED; + } + } + } +} + +int wiphy_read_of_freq_limits(struct wiphy *wiphy) +{ + struct device *dev = wiphy_dev(wiphy); + struct device_node *np; + struct property *prop; + struct ieee80211_freq_range *freq_limits; + unsigned int n_freq_limits; + const __be32 *p; + int len, i, err; + + if (!dev) + return 0; + np = dev_of_node(dev); + if (!np) + return 0; + + prop = of_find_property(np, "ieee80211-freq-limit", &len); + if (!prop) + return 0; + + if (!len || len % sizeof(u32) || len / sizeof(u32) % 2) { + dev_err(dev, "ieee80211-freq-limit wrong format"); + return -EPROTO; + } + n_freq_limits = len / sizeof(u32) / 2; + + freq_limits = kcalloc(n_freq_limits, sizeof(*freq_limits), GFP_KERNEL); + if (!freq_limits) { + err = -ENOMEM; + goto out; + } + + p = NULL; + for (i = 0; i < n_freq_limits; i++) { + struct ieee80211_freq_range *limit = &freq_limits[i]; + + p = of_prop_next_u32(prop, p, &limit->start_freq_khz); + if (!p) { + err = -EINVAL; + goto out; + } + + p = of_prop_next_u32(prop, p, &limit->end_freq_khz); + if (!p) { + err = -EINVAL; + goto out; + } + + if (!limit->start_freq_khz || + !limit->end_freq_khz || + limit->start_freq_khz >= limit->end_freq_khz) { + err = -EINVAL; + goto out; + } + } + + wiphy_freq_limits_apply(wiphy, freq_limits, n_freq_limits); + + return 0; + +out: + dev_err(dev, "Failed to get limits: %d\n", err); + kfree(freq_limits); + return err; +} +EXPORT_SYMBOL(wiphy_read_of_freq_limits); diff --git a/net/wireless/reg.c b/net/wireless/reg.c index 5dbac37..bda0e9e 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -748,8 +748,8 @@ static bool is_valid_rd(const struct ieee80211_regdomain *rd) return true; } -static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range, - u32 center_freq_khz, u32 bw_khz) +bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range, + u32 center_freq_khz, u32 bw_khz) { u32 start_freq_khz, end_freq_khz; diff --git a/net/wireless/reg.h b/net/wireless/reg.h index f6ced31..b8e44ef 100644 --- a/net/wireless/reg.h +++ b/net/wireless/reg.h @@ -54,6 +54,8 @@ void regulatory_exit(void); int set_regdom(const struct ieee80211_regdomain *rd, enum ieee80211_regd_source regd_src); +bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_range, + u32 center_freq_khz, u32 bw_khz); unsigned int reg_get_max_bandwidth(const struct ieee80211_regdomain *rd, const struct ieee80211_reg_rule *rule);