ieee802154: add support for CCA mode in wpan phys

The standard describes four modes of clear channel assesment: "energy
above threshold", "carrier found", and the logical and/or of these two.
Support for CCA mode setting is included in the at86rf230 driver,
predicated for RF212 chips.

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

7 files changed, 57 insertions, 3 deletions

diff --git a/drivers/net/ieee802154/at86rf230.c b/drivers/net/ieee802154/at86rf230.c
index 3d40c2350261..c60871aff333 100644
--- a/drivers/net/ieee802154/at86rf230.c
+++ b/drivers/net/ieee802154/at86rf230.c
@@ -794,6 +794,14 @@ at86rf212_set_lbt(struct ieee802154_dev *dev, bool on)
         return at86rf230_write_subreg(lp, SR_CSMA_LBT_MODE, on);
 }
 
+static int
+at86rf212_set_cca_mode(struct ieee802154_dev *dev, u8 mode)
+{
+        struct at86rf230_local *lp = dev->priv;
+
+        return at86rf230_write_subreg(lp, SR_CCA_MODE, mode);
+}
+
 static struct ieee802154_ops at86rf230_ops = {
         .owner = THIS_MODULE,
         .xmit = at86rf230_xmit,
@@ -814,6 +822,7 @@ static struct ieee802154_ops at86rf212_ops = {
         .set_hw_addr_filt = at86rf230_set_hw_addr_filt,
         .set_txpower = at86rf212_set_txpower,
         .set_lbt = at86rf212_set_lbt,
+        .set_cca_mode = at86rf212_set_cca_mode,
 };
 
 static void at86rf230_irqwork(struct work_struct *work)
diff --git a/include/linux/nl802154.h b/include/linux/nl802154.h
index 326baee227f7..5edefc14bd83 100644
--- a/include/linux/nl802154.h
+++ b/include/linux/nl802154.h
@@ -72,6 +72,7 @@ enum {
 
         IEEE802154_ATTR_TXPOWER,
         IEEE802154_ATTR_LBT_ENABLED,
+        IEEE802154_ATTR_CCA_MODE,
 
         __IEEE802154_ATTR_MAX,
 };
diff --git a/include/net/mac802154.h b/include/net/mac802154.h
index 521edcb0e586..1a98e5014e66 100644
--- a/include/net/mac802154.h
+++ b/include/net/mac802154.h
@@ -122,6 +122,10 @@ struct ieee802154_dev {
  *        Enables or disables listen before talk on the device. Called with
  *        pib_lock held.
  *        Returns either zero, or negative errno.
+ *
+ * set_cca_mode
+ *        Sets the CCA mode used by the device. Called with pib_lock held.
+ *        Returns either zero, or negative errno.
  */
 struct ieee802154_ops {
         struct module   *owner;
@@ -140,6 +144,7 @@ struct ieee802154_ops {
                                      u8 addr[IEEE802154_ADDR_LEN]);
         int             (*set_txpower)(struct ieee802154_dev *dev, int db);
         int             (*set_lbt)(struct ieee802154_dev *dev, bool on);
+        int             (*set_cca_mode)(struct ieee802154_dev *dev, u8 mode);
 };
 
 /* Basic interface to register ieee802154 device */
diff --git a/include/net/wpan-phy.h b/include/net/wpan-phy.h
index 804e6c4f5f8a..03b59051972d 100644
--- a/include/net/wpan-phy.h
+++ b/include/net/wpan-phy.h
@@ -58,6 +58,7 @@ struct wpan_phy {
 
         int (*set_txpower)(struct wpan_phy *phy, int db);
         int (*set_lbt)(struct wpan_phy *phy, bool on);
+        int (*set_cca_mode)(struct wpan_phy *phy, u8 cca_mode);
 
         char priv[0] __attribute__((__aligned__(NETDEV_ALIGN)));
 };
diff --git a/net/ieee802154/nl-phy.c b/net/ieee802154/nl-phy.c
index f029310b0662..36f58d633868 100644
--- a/net/ieee802154/nl-phy.c
+++ b/net/ieee802154/nl-phy.c
@@ -57,7 +57,8 @@ static int ieee802154_nl_fill_phy(struct sk_buff *msg, u32 portid,
             nla_put_u8(msg, IEEE802154_ATTR_PAGE, phy->current_page) ||
             nla_put_u8(msg, IEEE802154_ATTR_CHANNEL, phy->current_channel) ||
             nla_put_s8(msg, IEEE802154_ATTR_TXPOWER, phy->transmit_power) ||
-            nla_put_u8(msg, IEEE802154_ATTR_LBT_ENABLED, phy->lbt))
+            nla_put_u8(msg, IEEE802154_ATTR_LBT_ENABLED, phy->lbt) ||
+            nla_put_u8(msg, IEEE802154_ATTR_CCA_MODE, phy->cca_mode))
                 goto nla_put_failure;
         for (i = 0; i < 32; i++) {
                 if (phy->channels_supported[i])
@@ -385,6 +386,23 @@ static int phy_set_lbt(struct wpan_phy *phy, struct genl_info *info)
         return 0;
 }
 
+static int phy_set_cca_mode(struct wpan_phy *phy, struct genl_info *info)
+{
+        u8 mode = nla_get_u8(info->attrs[IEEE802154_ATTR_CCA_MODE]);
+        int rc;
+
+        if (mode > 3)
+                return -EINVAL;
+
+        rc = phy->set_cca_mode(phy, mode);
+        if (rc < 0)
+                return rc;
+
+        phy->cca_mode = mode;
+
+        return 0;
+}
+
 int ieee802154_set_phyparams(struct sk_buff *skb, struct genl_info *info)
 {
         struct wpan_phy *phy;
@@ -394,7 +412,8 @@ int ieee802154_set_phyparams(struct sk_buff *skb, struct genl_info *info)
         pr_debug("%s\n", __func__);
 
         if (!info->attrs[IEEE802154_ATTR_PHY_NAME] &&
-            !info->attrs[IEEE802154_ATTR_LBT_ENABLED])
+            !info->attrs[IEEE802154_ATTR_LBT_ENABLED] &&
+            !info->attrs[IEEE802154_ATTR_CCA_MODE])
                 return -EINVAL;
 
         name = nla_data(info->attrs[IEEE802154_ATTR_PHY_NAME]);
@@ -406,7 +425,8 @@ int ieee802154_set_phyparams(struct sk_buff *skb, struct genl_info *info)
                 return -ENODEV;
 
         if ((!phy->set_txpower && info->attrs[IEEE802154_ATTR_TXPOWER]) ||
-            (!phy->set_lbt && info->attrs[IEEE802154_ATTR_LBT_ENABLED]))
+            (!phy->set_lbt && info->attrs[IEEE802154_ATTR_LBT_ENABLED]) ||
+            (!phy->set_cca_mode && info->attrs[IEEE802154_ATTR_CCA_MODE]))
                 goto out;
 
         mutex_lock(&phy->pib_lock);
@@ -423,6 +443,12 @@ int ieee802154_set_phyparams(struct sk_buff *skb, struct genl_info *info)
                         goto error;
         }
 
+        if (info->attrs[IEEE802154_ATTR_CCA_MODE]) {
+                rc = phy_set_cca_mode(phy, info);
+                if (rc < 0)
+                        goto error;
+        }
+
         mutex_unlock(&phy->pib_lock);
 
         wpan_phy_put(phy);
diff --git a/net/ieee802154/nl_policy.c b/net/ieee802154/nl_policy.c
index a09f6423a6e9..d87c2c904110 100644
--- a/net/ieee802154/nl_policy.c
+++ b/net/ieee802154/nl_policy.c
@@ -55,5 +55,6 @@ const struct nla_policy ieee802154_policy[IEEE802154_ATTR_MAX + 1] = {
 
         [IEEE802154_ATTR_TXPOWER] = { .type = NLA_S8, },
         [IEEE802154_ATTR_LBT_ENABLED] = { .type = NLA_U8, },
+        [IEEE802154_ATTR_CCA_MODE] = { .type = NLA_U8, },
 };
 
diff --git a/net/mac802154/ieee802154_dev.c b/net/mac802154/ieee802154_dev.c
index 56338c8cfc33..4965e4ce6b5b 100644
--- a/net/mac802154/ieee802154_dev.c
+++ b/net/mac802154/ieee802154_dev.c
@@ -185,6 +185,16 @@ static int mac802154_set_lbt(struct wpan_phy *phy, bool on)
         return priv->ops->set_lbt(&priv->hw, on);
 }
 
+static int mac802154_set_cca_mode(struct wpan_phy *phy, u8 mode)
+{
+        struct mac802154_priv *priv = wpan_phy_priv(phy);
+
+        if (!priv->ops->set_cca_mode)
+                return -ENOTSUPP;
+
+        return priv->ops->set_cca_mode(&priv->hw, mode);
+}
+
 struct ieee802154_dev *
 ieee802154_alloc_device(size_t priv_data_len, struct ieee802154_ops *ops)
 {
@@ -264,6 +274,7 @@ int ieee802154_register_device(struct ieee802154_dev *dev)
         priv->phy->del_iface = mac802154_del_iface;
         priv->phy->set_txpower = mac802154_set_txpower;
         priv->phy->set_lbt = mac802154_set_lbt;
+        priv->phy->set_cca_mode = mac802154_set_cca_mode;
 
         rc = wpan_phy_register(priv->phy);
         if (rc < 0)