brcmutil: add field storing control channel to the struct brcmu_chan

Our d11 code supports encoding/decoding channel info into/from chanspec
format used by firmware. Current implementation is quite misleading
because of the way "chnum" field is used.
When encoding channel info, "chnum" has to be filled by a caller with
*center* channel number. However when decoding chanspec the same field
is filled with a *control* channel number.

1) This can be confusing. It's expected for information to be the same
   after encoding and decoding.
2) It doesn't allow accessing all info when decoding. Some functions may
   need to know both channel numbers, e.g. cfg80211 callback getting
   current channel.
Solve this by adding a separated field for control channel.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Reviewed-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/drivers/net/wireless/broadcom/brcm80211/include/brcmu_d11.h b/drivers/net/wireless/broadcom/brcm80211/include/brcmu_d11.h
index f9745ea8b3e0..8b8b2ecb3199 100644
--- a/drivers/net/wireless/broadcom/brcm80211/include/brcmu_d11.h
+++ b/drivers/net/wireless/broadcom/brcm80211/include/brcmu_d11.h
@@ -125,14 +125,36 @@ enum brcmu_chan_sb {
 	BRCMU_CHAN_SB_UU = BRCMU_CHAN_SB_LUU,
 };
 
+/**
+ * struct brcmu_chan - stores channel formats
+ *
+ * This structure can be used with functions translating chanspec into generic
+ * channel info and the other way.
+ *
+ * @chspec: firmware specific format
+ * @chnum: center channel number
+ * @control_ch_num: control channel number
+ * @band: frequency band
+ * @bw: channel width
+ * @sb: control sideband (location of control channel against the center one)
+ */
 struct brcmu_chan {
 	u16 chspec;
 	u8 chnum;
+	u8 control_ch_num;
 	u8 band;
 	enum brcmu_chan_bw bw;
 	enum brcmu_chan_sb sb;
 };
 
+/**
+ * struct brcmu_d11inf - provides functions translating channel format
+ *
+ * @io_type: determines version of channel format used by firmware
+ * @encchspec: encodes channel info into a chanspec, requires center channel
+ *	number, ignores control one
+ * @decchspec: decodes chanspec into generic info
+ */
 struct brcmu_d11inf {
 	u8 io_type;