2017-01-03 11:03:55

by Rafał Miłecki

[permalink] [raw]
Subject: [PATCH V4 1/2] dt-bindings: document common IEEE 802.11 frequency limit property

From: Rafał Miłecki <[email protected]>

This new file should be used for properties that apply to all wireless
devices.

Signed-off-by: Rafał Miłecki <[email protected]>
---
V2: Switch to a single ieee80211-freq-limit property that allows specifying
*multiple* ranges. This resolves problem with more complex rules as pointed
by Felx.
Make description implementation agnostic as pointed by Arend.
Rename node to wifi as suggested by Martin.
V3: Use more real-life frequencies in the example.
---
.../devicetree/bindings/net/wireless/ieee80211.txt | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/wireless/ieee80211.txt

diff --git a/Documentation/devicetree/bindings/net/wireless/ieee80211.txt b/Documentation/devicetree/bindings/net/wireless/ieee80211.txt
new file mode 100644
index 0000000..0cd1219
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/wireless/ieee80211.txt
@@ -0,0 +1,18 @@
+Common IEEE 802.11 properties
+
+This provides documentation of common properties that are valid for all wireless
+devices.
+
+Optional properties:
+ - ieee80211-freq-limit : list of supported frequency ranges in KHz
+
+Example:
+
+pcie@0,0 {
+ reg = <0x0000 0 0 0 0>;
+ wifi@0,0 {
+ reg = <0x0000 0 0 0 0>;
+ ieee80211-freq-limit = <2402000 2482000>,
+ <5170000 5250000>;
+ };
+};
--
2.10.1


2017-01-03 23:09:41

by Rob Herring (Arm)

[permalink] [raw]
Subject: Re: [PATCH V4 1/2] dt-bindings: document common IEEE 802.11 frequency limit property

On Tue, Jan 03, 2017 at 12:03:38PM +0100, Rafał Miłecki wrote:
> From: Rafał Miłecki <[email protected]>
>
> This new file should be used for properties that apply to all wireless
> devices.

The commit msg should answer the questions I asked on v1.

> Signed-off-by: Rafał Miłecki <[email protected]>
> ---
> V2: Switch to a single ieee80211-freq-limit property that allows specifying
> *multiple* ranges. This resolves problem with more complex rules as pointed
> by Felx.
> Make description implementation agnostic as pointed by Arend.
> Rename node to wifi as suggested by Martin.
> V3: Use more real-life frequencies in the example.
> ---
> .../devicetree/bindings/net/wireless/ieee80211.txt | 18 ++++++++++++++++++
> 1 file changed, 18 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/net/wireless/ieee80211.txt
>
> diff --git a/Documentation/devicetree/bindings/net/wireless/ieee80211.txt b/Documentation/devicetree/bindings/net/wireless/ieee80211.txt
> new file mode 100644
> index 0000000..0cd1219
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/wireless/ieee80211.txt
> @@ -0,0 +1,18 @@
> +Common IEEE 802.11 properties
> +
> +This provides documentation of common properties that are valid for all wireless
> +devices.
> +
> +Optional properties:
> + - ieee80211-freq-limit : list of supported frequency ranges in KHz
> +
> +Example:
> +
> +pcie@0,0 {
> + reg = <0x0000 0 0 0 0>;
> + wifi@0,0 {
> + reg = <0x0000 0 0 0 0>;
> + ieee80211-freq-limit = <2402000 2482000>,
> + <5170000 5250000>;
> + };
> +};
> --
> 2.10.1
>
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html

2017-01-03 13:30:04

by Arend Van Spriel

[permalink] [raw]
Subject: Re: [PATCH V4 3/2] brcmfmac: use wiphy_read_of_freq_limits to respect extra limits

What is with the patch numbering, ie. 3/2?

On 3-1-2017 12:03, Rafał Miłecki wrote:
> From: Rafał Miłecki <[email protected]>
>
> 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 on DT to support such devices properly.
>
> This patch adds check for channel being disabled with orig_flags which
> is how this wiphy helper works.

this is the first mention about the wiphy helper. Probably need
statement here that call to wiphy_read_of_freq_limits() was added in
this patch which applies the extra limitation info read from DT.

> Signed-off-by: Rafał Miłecki <[email protected]>
> ---
> This patch should probably go through wireless-driver-next, 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
> ---
> drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
> index ccae3bb..f95e316 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;
> +
> /* assuming the chanspecs order is HT20,
> * HT40 upper, HT40 lower, and VHT80.
> */
> @@ -6477,6 +6480,7 @@ static int brcmf_setup_wiphy(struct wiphy *wiphy, struct brcmf_if *ifp)
> wiphy->bands[NL80211_BAND_5GHZ] = band;
> }
> }
> + wiphy_read_of_freq_limits(wiphy);

The return value is ignored, which I suppose is fine. So does the
function need a return value at all? Is there a scenario where the DT
info *must* be supplied?

Regards,
Arend

2017-01-03 14:17:46

by Rafał Miłecki

[permalink] [raw]
Subject: Re: [PATCH V4 2/2] cfg80211: support ieee80211-freq-limit DT property

On 3 January 2017 at 13:10, Arend Van Spriel
<[email protected]> wrote:
> On 3-1-2017 12:03, Rafa=C5=82 Mi=C5=82ecki wrote:
>> From: Rafa=C5=82 Mi=C5=82ecki <[email protected]>
>>
>> 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: Rafa=C5=82 Mi=C5=82ecki <[email protected]>
>> ---
>> V2: Put main code in core.c as it isn't strictly part of regulatory - po=
inted
>> 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 (d=
isable
>> + * unavailable ones). It's usually a *bad* idea to use it in drivers wi=
th
>> + * shared channel data as DT limitations are device specific.
>> + *
>> + * As this function access device node it has to be called after set_wi=
phy_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_regdo=
main *rd)
>> return true;
>> }
>>
>> -static bool reg_does_bw_fit(const struct ieee80211_freq_range *freq_ran=
ge,
>> - 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?

--=20
Rafa=C5=82

2017-01-03 11:03:59

by Rafał Miłecki

[permalink] [raw]
Subject: [PATCH V4 3/2] brcmfmac: use wiphy_read_of_freq_limits to respect extra limits

From: Rafał Miłecki <[email protected]>

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 on DT to support such devices properly.

This patch adds check for channel being disabled with orig_flags which
is how this wiphy helper works.

Signed-off-by: Rafał Miłecki <[email protected]>
---
This patch should probably go through wireless-driver-next, 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
---
drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
index ccae3bb..f95e316 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;
+
/* assuming the chanspecs order is HT20,
* HT40 upper, HT40 lower, and VHT80.
*/
@@ -6477,6 +6480,7 @@ static int brcmf_setup_wiphy(struct wiphy *wiphy, struct brcmf_if *ifp)
wiphy->bands[NL80211_BAND_5GHZ] = band;
}
}
+ wiphy_read_of_freq_limits(wiphy);
err = brcmf_setup_wiphybands(wiphy);
return err;
}
--
2.10.1

2017-01-03 14:24:13

by Rafał Miłecki

[permalink] [raw]
Subject: Re: [PATCH V4 3/2] brcmfmac: use wiphy_read_of_freq_limits to respect extra limits

On 3 January 2017 at 14:29, Arend Van Spriel
<[email protected]> wrote:
> What is with the patch numbering, ie. 3/2?

It's my small trick related to the "This patch should probably go
through wireless-driver-next" ;) I wanted to make it clear that only 2
patches are strictly targeted for the mac80211-next tree.


> On 3-1-2017 12:03, Rafa=C5=82 Mi=C5=82ecki wrote:
>> From: Rafa=C5=82 Mi=C5=82ecki <[email protected]>
>>
>> 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 on DT to support such devices properly.
>>
>> This patch adds check for channel being disabled with orig_flags which
>> is how this wiphy helper works.
>
> this is the first mention about the wiphy helper. Probably need
> statement here that call to wiphy_read_of_freq_limits() was added in
> this patch which applies the extra limitation info read from DT.

OK, I'll improve this description.


>> Signed-off-by: Rafa=C5=82 Mi=C5=82ecki <[email protected]>
>> ---
>> This patch should probably go through wireless-driver-next, 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
>> ---
>> drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 4 ++++
>> 1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c=
b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
>> index ccae3bb..f95e316 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_c=
fg80211_info *cfg,
>> band->band);
>> channel[index].hw_value =3D ch.control_ch_num;
>>
>> + if (channel->orig_flags & IEEE80211_CHAN_DISABLED)
>> + continue;
>> +
>> /* assuming the chanspecs order is HT20,
>> * HT40 upper, HT40 lower, and VHT80.
>> */
>> @@ -6477,6 +6480,7 @@ static int brcmf_setup_wiphy(struct wiphy *wiphy, =
struct brcmf_if *ifp)
>> wiphy->bands[NL80211_BAND_5GHZ] =3D band;
>> }
>> }
>> + wiphy_read_of_freq_limits(wiphy);
>
> The return value is ignored, which I suppose is fine. So does the
> function need a return value at all? Is there a scenario where the DT
> info *must* be supplied?

To be honest, I can't decide. Right now I don't see a point of
checking that function result (as you noticed, it should never be
required). If no one objects, I'll try switching that function to
void.

--=20
Rafa=C5=82

2017-01-03 12:10:32

by Arend Van Spriel

[permalink] [raw]
Subject: Re: [PATCH V4 2/2] cfg80211: support ieee80211-freq-limit DT property

On 3-1-2017 12:03, Rafał Miłecki wrote:
> From: Rafał Miłecki <[email protected]>
>
> 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 <[email protected]>
> ---
> 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

2017-01-03 11:03:57

by Rafał Miłecki

[permalink] [raw]
Subject: [PATCH V4 2/2] cfg80211: support ieee80211-freq-limit DT property

From: Rafał Miłecki <[email protected]>

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 <[email protected]>
---
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.
+ * 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 <[email protected]>
+ *
+ * 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);

--
2.10.1