iw: add set sar_specs command

Add set sar_specs command

usage: iw <phy> set sar_specs <sar type> <range index:sar power>*
e.g.
iw phy0 set sar_specs 0 0:100 1:90 2:80...
where sar type should correspond to wiphy's sar_capa,
and range index should be valid in wiphy's sar_capa.

For now, kernel sar type supports only 0 (NL80211_SAR_TYPE_POWER)
which means that the sar power limitation is specified in 0.25dBm unit.

Cc: Carl Huang <cjhuang@codeaurora.org>
Signed-off-by: Zong-Zhe Yang <kevin_yang@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://lore.kernel.org/r/20211007085615.40399-1-pkshih@realtek.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/sar.c b/sar.c
new file mode 100644 (file)
index 0000000..5ab54ec
--- /dev/null
+++ b/sar.c
@@ -0,0 +1,71 @@
+#include <errno.h>
+#include <string.h>
+
+#include <netlink/genl/genl.h>
+#include <netlink/msg.h>
+#include <netlink/attr.h>
+
+#include "nl80211.h"
+#include "iw.h"
+
+static int set_sar_specs(struct nl80211_state *state,
+                        struct nl_msg *msg,
+                        int argc, char **argv,
+                        enum id_input id)
+{
+       struct nlattr *nl_sar, *nl_specs, *nl_sub;
+       enum nl80211_sar_type type;
+       __u32 idx;
+       __s32 pwr;
+       char *tmp;
+       int count, i;
+
+       if (argc <= 1)
+               return -EINVAL;
+
+       type = atoi(argv[0]);
+
+       nl_sar = nla_nest_start(msg, NL80211_ATTR_SAR_SPEC);
+       if (!nl_sar)
+               goto nla_put_failure;
+
+       NLA_PUT_U32(msg, NL80211_SAR_ATTR_TYPE, type);
+
+       nl_specs = nla_nest_start(msg, NL80211_SAR_ATTR_SPECS);
+       if (!nl_specs)
+               goto nla_put_failure;
+
+       for (i = 1; i < argc; i++) {
+               tmp = strchr(argv[i], ':');
+               if (!tmp)
+                       return -EINVAL;
+
+               if (tmp != strrchr(argv[i], ':'))
+                       return -EINVAL;
+
+               count = sscanf(argv[i], "%u:%d", &idx, &pwr);
+               if (count != 2)
+                       return -EINVAL;
+
+               nl_sub = nla_nest_start(msg, i - 1);
+               if (!nl_sub)
+                       goto nla_put_failure;
+
+               NLA_PUT_U32(msg, NL80211_SAR_ATTR_SPECS_RANGE_INDEX, idx);
+               NLA_PUT_S32(msg, NL80211_SAR_ATTR_SPECS_POWER, pwr);
+
+               nla_nest_end(msg, nl_sub);
+       }
+
+       nla_nest_end(msg, nl_specs);
+       nla_nest_end(msg, nl_sar);
+
+       return 0;
+
+ nla_put_failure:
+       return -ENOBUFS;
+}
+
+COMMAND(set, sar_specs, "<sar type> <range index:sar power>*",
+       NL80211_CMD_SET_SAR_SPECS, 0, CIB_PHY, set_sar_specs,
+       "Set SAR specs corresponding to SAR capa of wiphy.");