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 284e2f6..47e02c1 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 ccdff79..03f8818 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 aaf9832..1a877de 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);