This adds MCS set parsing to iw. When you can 'iw list' you can
now see the MCS set actually parsed, this can tell you information
such as all the RX/TX MCS indexes supported, max TX spatial streams,
if TX unequal modulation is supported and your max supported HT
RX data rate.
This is as per 802.11n Draft 7 on section 7.3.2.57.4 Supported MCS Set field.
Signed-off-by: Luis R. Rodriguez <lrodriguez@xxxxxxxxxxx>
---
I don't see anything on the max HT RX rate though, so cannot test that.
My HT APs are also being shipped from NJ so I have no APs to test against
which I can go and tweak to ensure HT is enabled as I want. Please test
and review.
info.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 57 insertions(+), 0 deletions(-)
diff --git a/info.c b/info.c
index bf3b8bd..cabd4b6 100644
--- a/info.c
+++ b/info.c
@@ -1,3 +1,4 @@
+#include <stdbool.h>
#include <errno.h>
#include <net/if.h>
@@ -20,6 +21,24 @@ static void print_flag(const char *name, int *open)
*open = 1;
}
+static void print_mcs_index(unsigned char *mcs)
+{
+ unsigned int mcs_bit;
+
+ for (mcs_bit = 0; mcs_bit <= 76; mcs_bit++) {
+ unsigned int mcs_octet = mcs_bit/8;
+ unsigned int MCS_RATE_BIT = 1 << mcs_bit % 8;
+ bool mcs_rate_idx_set;
+
+ mcs_rate_idx_set = !!(mcs[mcs_octet] & MCS_RATE_BIT);
+
+ if (!mcs_rate_idx_set)
+ continue;
+
+ printf("\t\t\tMCS index %d\n", mcs_bit);
+ }
+}
+
static int print_phy_handler(struct nl_msg *msg, void *arg)
{
struct nlattr *tb_msg[NL80211_ATTR_MAX + 1];
@@ -128,10 +147,48 @@ static int print_phy_handler(struct nl_msg *msg, void *arg)
}
if (tb_band[NL80211_BAND_ATTR_HT_MCS_SET] &&
nla_len(tb_band[NL80211_BAND_ATTR_HT_MCS_SET]) == 16) {
+ /* As defined in 7.3.2.57.4 Supported MCS Set field */
+ unsigned int tx_max_num_spatial_streams, max_rx_supp_data_rate;
unsigned char *mcs = nla_data(tb_band[NL80211_BAND_ATTR_HT_MCS_SET]);
+ bool tx_mcs_set_defined, tx_mcs_set_equal, tx_unequal_modulation;
+
printf("\t\tHT MCS set: %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x %.2x\n",
mcs[0], mcs[1], mcs[2], mcs[3], mcs[4], mcs[5], mcs[6], mcs[7],
mcs[8], mcs[9], mcs[10], mcs[11], mcs[12], mcs[13], mcs[14], mcs[15]);
+
+ max_rx_supp_data_rate = ((mcs[10] >> 8) & ((mcs[11] & 0x3) << 8));
+ tx_mcs_set_defined = !!(mcs[12] & (1 << 0));
+ tx_mcs_set_equal = !(mcs[12] & (1 << 1));
+ tx_max_num_spatial_streams = (mcs[12] | ((1 << 3) | (1 << 4))) + 1;
+ tx_unequal_modulation = !!(mcs[12] & (1 << 5));
+
+ printf("\t\tHT Max RX data rate: %d Mbps\n", max_rx_supp_data_rate);
+
+ if (tx_mcs_set_defined) {
+ if (tx_mcs_set_equal) {
+ printf("\t\tHT TX/RX MCS rate indexes supported:\n");
+ print_mcs_index(&mcs[0]);
+ } else {
+ printf("\t\tHT RX MCS rate indexes supported:\n");
+ print_mcs_index(&mcs[0]);
+
+ if (tx_unequal_modulation)
+ printf("TX unequal modulation supported\n");
+ else
+ printf("TX unequal modulation not supported\n");
+
+ printf("\t\tHT TX Max spatiel streams: %d\n",
+ tx_max_num_spatial_streams);
+
+ printf("\t\tHT TX MCS rate indexes supported may differ\n");
+ }
+ }
+ else {
+ printf("\t\tHT RX MCS rate indexes supported:\n");
+ print_mcs_index(&mcs[0]);
+ printf("\t\tHT TX MCS rates indexes are undefined\n");
+ }
+
}
#endif
--
1.6.1.2.253.ga34a
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
