From e691ac2f75b69bee743f0370d79454ba4429b175 Mon Sep 17 00:00:00 2001 From: Rafał Miłecki Date: Wed, 4 Jan 2017 18:58:31 +0100 Subject: cfg80211: support ieee80211-freq-limit DT property MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This patch adds a helper for reading that new property and applying limitations of supported channels specified this way. It is used with devices that normally support a wide wireless band but in a given config are limited to some part of it (usually due to board design). For example a dual-band chipset may be able to support one band only because of used antennas. It's also common that tri-band routers have separated radios for lower and higher part of 5 GHz band and it may be impossible to say which is which without a DT info. Signed-off-by: Rafał Miłecki [add new function to documentation, fix link] Signed-off-by: Johannes Berg --- include/net/cfg80211.h | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'include/net/cfg80211.h') diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index ca2ac1ce5862..41a9ecd82ca0 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -311,6 +311,34 @@ 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 external 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. You should make + * sure to call it only if channels in wiphy are copied and can be modified + * without affecting other devices. + * + * 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. + * If using this helper, call it before wiphy_register(). + */ +#ifdef CONFIG_OF +void wiphy_read_of_freq_limits(struct wiphy *wiphy); +#else /* CONFIG_OF */ +static inline void wiphy_read_of_freq_limits(struct wiphy *wiphy) +{ +} +#endif /* !CONFIG_OF */ + + /* * Wireless hardware/device configuration structures and methods */ -- cgit v1.2.3-58-ga151