ieee802154: add TX power control to wpan_phy

Replace the current u8 transmit_power in wpan_phy with s8 transmit_power.
The u8 field contained the actual tx power and a tolerance field,
which no physical radio every used. Adjust sysfs entries to keep
compatibility with userspace, give tolerances of +-1dB statically there.

This patch only adds support for this in the at86rf230 driver and the
RF212 chip. Configuration calculation for RF212 is also somewhat basic,
but does the job - the RF212 datasheet gives a large table with
suggested values for combinations of TX power and page/channel, if this
does not work well, we might have to copy the whole table.

Signed-off-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 64 insertions, 4 deletions

diff --git a/net/ieee802154/ieee802154.h b/net/ieee802154/ieee802154.h
index cee4425b9956..6cbc8965be91 100644
--- a/net/ieee802154/ieee802154.h
+++ b/net/ieee802154/ieee802154.h
@@ -53,6 +53,7 @@ int ieee802154_list_phy(struct sk_buff *skb, struct genl_info *info);
 int ieee802154_dump_phy(struct sk_buff *skb, struct netlink_callback *cb);
 int ieee802154_add_iface(struct sk_buff *skb, struct genl_info *info);
 int ieee802154_del_iface(struct sk_buff *skb, struct genl_info *info);
+int ieee802154_set_phyparams(struct sk_buff *skb, struct genl_info *info);
 
 enum ieee802154_mcgrp_ids {
         IEEE802154_COORD_MCGRP,
diff --git a/net/ieee802154/netlink.c b/net/ieee802154/netlink.c
index 43f1b2bf469f..67c151bf4b91 100644
--- a/net/ieee802154/netlink.c
+++ b/net/ieee802154/netlink.c
@@ -115,6 +115,7 @@ static const struct genl_ops ieee8021154_ops[] = {
                         ieee802154_dump_phy),
         IEEE802154_OP(IEEE802154_ADD_IFACE, ieee802154_add_iface),
         IEEE802154_OP(IEEE802154_DEL_IFACE, ieee802154_del_iface),
+        IEEE802154_OP(IEEE802154_SET_PHYPARAMS, ieee802154_set_phyparams),
         /* see nl-mac.c */
         IEEE802154_OP(IEEE802154_ASSOCIATE_REQ, ieee802154_associate_req),
         IEEE802154_OP(IEEE802154_ASSOCIATE_RESP, ieee802154_associate_resp),
diff --git a/net/ieee802154/nl-phy.c b/net/ieee802154/nl-phy.c
index 89b265aea151..d3ee62fbae99 100644
--- a/net/ieee802154/nl-phy.c
+++ b/net/ieee802154/nl-phy.c
@@ -55,7 +55,8 @@ static int ieee802154_nl_fill_phy(struct sk_buff *msg, u32 portid,
         mutex_lock(&phy->pib_lock);
         if (nla_put_string(msg, IEEE802154_ATTR_PHY_NAME, wpan_phy_name(phy)) ||
             nla_put_u8(msg, IEEE802154_ATTR_PAGE, phy->current_page) ||
-            nla_put_u8(msg, IEEE802154_ATTR_CHANNEL, phy->current_channel))
+            nla_put_u8(msg, IEEE802154_ATTR_CHANNEL, phy->current_channel) ||
+            nla_put_s8(msg, IEEE802154_ATTR_TXPOWER, phy->transmit_power))
                 goto nla_put_failure;
         for (i = 0; i < 32; i++) {
                 if (phy->channels_supported[i])
@@ -354,3 +355,49 @@ out_dev:
 
         return rc;
 }
+
+int ieee802154_set_phyparams(struct sk_buff *skb, struct genl_info *info)
+{
+        struct wpan_phy *phy;
+        const char *name;
+        int txpower;
+        int rc = -EINVAL;
+
+        pr_debug("%s\n", __func__);
+
+        if (!info->attrs[IEEE802154_ATTR_PHY_NAME])
+                return -EINVAL;
+
+        name = nla_data(info->attrs[IEEE802154_ATTR_PHY_NAME]);
+        if (name[nla_len(info->attrs[IEEE802154_ATTR_PHY_NAME]) - 1] != '\0')
+                return -EINVAL; /* phy name should be null-terminated */
+
+        txpower = nla_get_s8(info->attrs[IEEE802154_ATTR_TXPOWER]);
+
+        phy = wpan_phy_find(name);
+        if (!phy)
+                return -ENODEV;
+
+        if (!phy->set_txpower)
+                goto out;
+
+        mutex_lock(&phy->pib_lock);
+
+        rc = phy->set_txpower(phy, txpower);
+        if (rc < 0) {
+                mutex_unlock(&phy->pib_lock);
+                goto out;
+        }
+
+        phy->transmit_power = txpower;
+
+        mutex_unlock(&phy->pib_lock);
+
+        wpan_phy_put(phy);
+
+        return 0;
+
+out:
+        wpan_phy_put(phy);
+        return rc;
+}
diff --git a/net/ieee802154/nl_policy.c b/net/ieee802154/nl_policy.c
index 6adda4d46f95..90b1d0d2c14e 100644
--- a/net/ieee802154/nl_policy.c
+++ b/net/ieee802154/nl_policy.c
@@ -52,5 +52,7 @@ const struct nla_policy ieee802154_policy[IEEE802154_ATTR_MAX + 1] = {
         [IEEE802154_ATTR_DURATION] = { .type = NLA_U8, },
         [IEEE802154_ATTR_ED_LIST] = { .len = 27 },
         [IEEE802154_ATTR_CHANNEL_PAGE_LIST] = { .len = 32 * 4, },
+
+        [IEEE802154_ATTR_TXPOWER] = { .type = NLA_S8, },
 };
 
diff --git a/net/ieee802154/wpan-class.c b/net/ieee802154/wpan-class.c
index 4dd37615a749..8d6f6704da84 100644
--- a/net/ieee802154/wpan-class.c
+++ b/net/ieee802154/wpan-class.c
@@ -44,9 +44,7 @@ static DEVICE_ATTR_RO(name);
 
 MASTER_SHOW(current_channel, "%d");
 MASTER_SHOW(current_page, "%d");
-MASTER_SHOW_COMPLEX(transmit_power, "%d +- %d dB",
-        ((signed char) (phy->transmit_power << 2)) >> 2,
-        (phy->transmit_power >> 6) ? (phy->transmit_power >> 6) * 3 : 1);
+MASTER_SHOW(transmit_power, "%d +- 1 dB");
 MASTER_SHOW(cca_mode, "%d");
 
 static ssize_t channels_supported_show(struct device *dev,
diff --git a/net/mac802154/ieee802154_dev.c b/net/mac802154/ieee802154_dev.c
index 52ae6646a411..9eb49e0886a4 100644
--- a/net/mac802154/ieee802154_dev.c
+++ b/net/mac802154/ieee802154_dev.c
@@ -165,6 +165,16 @@ err:
         return ERR_PTR(err);
 }
 
+static int mac802154_set_txpower(struct wpan_phy *phy, int db)
+{
+        struct mac802154_priv *priv = wpan_phy_priv(phy);
+
+        if (!priv->ops->set_txpower)
+                return -ENOTSUPP;
+
+        return priv->ops->set_txpower(&priv->hw, db);
+}
+
 struct ieee802154_dev *
 ieee802154_alloc_device(size_t priv_data_len, struct ieee802154_ops *ops)
 {
@@ -242,6 +252,7 @@ int ieee802154_register_device(struct ieee802154_dev *dev)
 
         priv->phy->add_iface = mac802154_add_iface;
         priv->phy->del_iface = mac802154_del_iface;
+        priv->phy->set_txpower = mac802154_set_txpower;
 
         rc = wpan_phy_register(priv->phy);
         if (rc < 0)