mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-22 20:23:57 +08:00
e691ac2f75
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 <rafal@milecki.pl> [add new function to documentation, fix link] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
139 lines
3.4 KiB
C
139 lines
3.4 KiB
C
/*
|
|
* 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 "core.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 (cfg80211_does_bw_fit_range(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->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->flags |= IEEE80211_CHAN_DISABLED;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
void 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;
|
|
int err = 0;
|
|
|
|
if (!dev)
|
|
return;
|
|
np = dev_of_node(dev);
|
|
if (!np)
|
|
return;
|
|
|
|
prop = of_find_property(np, "ieee80211-freq-limit", &len);
|
|
if (!prop)
|
|
return;
|
|
|
|
if (!len || len % sizeof(u32) || len / sizeof(u32) % 2) {
|
|
dev_err(dev, "ieee80211-freq-limit wrong format");
|
|
return;
|
|
}
|
|
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_kfree;
|
|
}
|
|
|
|
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_kfree;
|
|
}
|
|
|
|
p = of_prop_next_u32(prop, p, &limit->end_freq_khz);
|
|
if (!p) {
|
|
err = -EINVAL;
|
|
goto out_kfree;
|
|
}
|
|
|
|
if (!limit->start_freq_khz ||
|
|
!limit->end_freq_khz ||
|
|
limit->start_freq_khz >= limit->end_freq_khz) {
|
|
err = -EINVAL;
|
|
goto out_kfree;
|
|
}
|
|
}
|
|
|
|
wiphy_freq_limits_apply(wiphy, freq_limits, n_freq_limits);
|
|
|
|
out_kfree:
|
|
kfree(freq_limits);
|
|
if (err)
|
|
dev_err(dev, "Failed to get limits: %d\n", err);
|
|
}
|
|
EXPORT_SYMBOL(wiphy_read_of_freq_limits);
|