NFC: Add dev_up and dev_down control operations

Add 2 new nfc control operations:
dev_up to turn on the nfc device
dev_down to turn off the nfc device

Signed-off-by: Ilan Elias <ilane@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 137 insertions, 0 deletions

diff --git a/net/nfc/core.c b/net/nfc/core.c
index 284e2f6a14ff..47e02c1b8c02 100644
--- a/net/nfc/core.c
+++ b/net/nfc/core.c
@@ -53,6 +53,80 @@ int nfc_printk(const char *level, const char *format, ...)
 EXPORT_SYMBOL(nfc_printk);
 
 /**
+ * nfc_dev_up - turn on the NFC device
+ *
+ * @dev: The nfc device to be turned on
+ *
+ * The device remains up until the nfc_dev_down function is called.
+ */
+int nfc_dev_up(struct nfc_dev *dev)
+{
+        int rc = 0;
+
+        nfc_dbg("dev_name=%s", dev_name(&dev->dev));
+
+        device_lock(&dev->dev);
+
+        if (!device_is_registered(&dev->dev)) {
+                rc = -ENODEV;
+                goto error;
+        }
+
+        if (dev->dev_up) {
+                rc = -EALREADY;
+                goto error;
+        }
+
+        if (dev->ops->dev_up)
+                rc = dev->ops->dev_up(dev);
+
+        if (!rc)
+                dev->dev_up = true;
+
+error:
+        device_unlock(&dev->dev);
+        return rc;
+}
+
+/**
+ * nfc_dev_down - turn off the NFC device
+ *
+ * @dev: The nfc device to be turned off
+ */
+int nfc_dev_down(struct nfc_dev *dev)
+{
+        int rc = 0;
+
+        nfc_dbg("dev_name=%s", dev_name(&dev->dev));
+
+        device_lock(&dev->dev);
+
+        if (!device_is_registered(&dev->dev)) {
+                rc = -ENODEV;
+                goto error;
+        }
+
+        if (!dev->dev_up) {
+                rc = -EALREADY;
+                goto error;
+        }
+
+        if (dev->polling || dev->remote_activated) {
+                rc = -EBUSY;
+                goto error;
+        }
+
+        if (dev->ops->dev_down)
+                dev->ops->dev_down(dev);
+
+        dev->dev_up = false;
+
+error:
+        device_unlock(&dev->dev);
+        return rc;
+}
+
+/**
  * nfc_start_poll - start polling for nfc targets
  *
  * @dev: The nfc device that must start polling
@@ -144,6 +218,8 @@ int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
         }
 
         rc = dev->ops->activate_target(dev, target_idx, protocol);
+        if (!rc)
+                dev->remote_activated = true;
 
 error:
         device_unlock(&dev->dev);
@@ -170,6 +246,7 @@ int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx)
         }
 
         dev->ops->deactivate_target(dev, target_idx);
+        dev->remote_activated = false;
 
 error:
         device_unlock(&dev->dev);
diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
index ccdff7953f7d..03f8818e1f16 100644
--- a/net/nfc/netlink.c
+++ b/net/nfc/netlink.c
@@ -367,6 +367,52 @@ out_putdev:
         return rc;
 }
 
+static int nfc_genl_dev_up(struct sk_buff *skb, struct genl_info *info)
+{
+        struct nfc_dev *dev;
+        int rc;
+        u32 idx;
+
+        nfc_dbg("entry");
+
+        if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+                return -EINVAL;
+
+        idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+        dev = nfc_get_device(idx);
+        if (!dev)
+                return -ENODEV;
+
+        rc = nfc_dev_up(dev);
+
+        nfc_put_device(dev);
+        return rc;
+}
+
+static int nfc_genl_dev_down(struct sk_buff *skb, struct genl_info *info)
+{
+        struct nfc_dev *dev;
+        int rc;
+        u32 idx;
+
+        nfc_dbg("entry");
+
+        if (!info->attrs[NFC_ATTR_DEVICE_INDEX])
+                return -EINVAL;
+
+        idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
+
+        dev = nfc_get_device(idx);
+        if (!dev)
+                return -ENODEV;
+
+        rc = nfc_dev_down(dev);
+
+        nfc_put_device(dev);
+        return rc;
+}
+
 static int nfc_genl_start_poll(struct sk_buff *skb, struct genl_info *info)
 {
         struct nfc_dev *dev;
@@ -441,6 +487,16 @@ static struct genl_ops nfc_genl_ops[] = {
                 .policy = nfc_genl_policy,
         },
         {
+                .cmd = NFC_CMD_DEV_UP,
+                .doit = nfc_genl_dev_up,
+                .policy = nfc_genl_policy,
+        },
+        {
+                .cmd = NFC_CMD_DEV_DOWN,
+                .doit = nfc_genl_dev_down,
+                .policy = nfc_genl_policy,
+        },
+        {
                 .cmd = NFC_CMD_START_POLL,
                 .doit = nfc_genl_start_poll,
                 .policy = nfc_genl_policy,
diff --git a/net/nfc/nfc.h b/net/nfc/nfc.h
index aaf9832298f3..1a877de8e230 100644
--- a/net/nfc/nfc.h
+++ b/net/nfc/nfc.h
@@ -101,6 +101,10 @@ static inline void nfc_device_iter_exit(struct class_dev_iter *iter)
         class_dev_iter_exit(iter);
 }
 
+int nfc_dev_up(struct nfc_dev *dev);
+
+int nfc_dev_down(struct nfc_dev *dev);
+
 int nfc_start_poll(struct nfc_dev *dev, u32 protocols);
 
 int nfc_stop_poll(struct nfc_dev *dev);