[PATCH 2/2] add a new field for SERVICE field information

From: Benjamin Berg <[email protected]>

This can be used to report information used for bandwidth signalling.

Signed-off-by: Benjamin Berg <[email protected]>
---
 fields/SERVICE field.md | 42 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)
 create mode 100644 fields/SERVICE field.md

diff --git a/fields/SERVICE field.md b/fields/SERVICE field.md
new file mode 100644
index 0000000..ff9919b
--- /dev/null
+++ b/fields/SERVICE field.md	
@@ -0,0 +1,42 @@
+---
+title: SERVICE field
+categories: [defined]
+type: 36
+---
+Type
+: 36
+
+Structure
+: u8 known
+: u8 flags
+: u16 service\_field
+: u8 ch\_bw\_in\_non\_ht
+
+Unit(s)
+: none
+
+For some frames, the scrambler and SERVICE field bits may be used to encode
+further information about the frame. This field exists to report related
+information when available.
+
+The `known` field indicates which information is known:
+
+| **flag** | **definition** | **notes** |
+| 0x01 | service field known | The service field bits in `service_field` are valid. |
+| 0x02 | scrambler init known | The lower bits in `service_field` represent the scrambler initialization value. |
+| 0x03 | dynamic BW in non-HT known | In `ch_bw_in_non_ht` part of the field. |
+
+The `flags` field is any combination of the following:
+
+| **flag** | **definition** | **notes** |
+| 0x01 | dynamic BW in non-HT | Set if the dynamic BW in non-HT bit was set in the scrambler bits |
+| 0x02 | 11bit scrambler init | Set for frames that have 11 bit of scrambler initialization (e.g. EHT) |
+
+The `service_field` may contain both the scrambler initialization and the SERVICE field value
+that was received depending on the flags in `known`. The lower bits are used to store the
+scrambler initialization as the SERVICE field must be all zero there.
+The scrambler initialization may be 7 or 11 bit long depending on the PHY type of the frame.
+If it is 11 bit, then the corresponding bit is set in `flags`.
+
+The `ch_bw_in_non_ht` field contains the value of `CH_BANDWIDTH_IN_NON_HT` as defined in
+IEEE802.11REVmf-D1.0 Table 17-8 - "TXVECTOR parameter `CH_BANDWIDTH_IN_NON_HT` values".
-- 
2.51.1