NFC: Add secure element enablement internal API

Called via netlink, this API will enable or disable a specific secure
element. When a secure element is enabled, it will handle card emulation
and more generically ISO-DEP target mode, i.e. all target mode cases
except for p2p target mode.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

2 files changed, 109 insertions, 4 deletions

diff --git a/net/nfc/core.c b/net/nfc/core.c
index 5b60b9ddfc8f..dc96a83aa6ab 100644
--- a/net/nfc/core.c
+++ b/net/nfc/core.c
@@ -528,6 +528,108 @@ error:
         return rc;
 }
 
+static struct nfc_se *find_se(struct nfc_dev *dev, u32 se_idx)
+{
+        struct nfc_se *se, *n;
+
+        list_for_each_entry_safe(se, n, &dev->secure_elements, list)
+                if (se->idx == se_idx)
+                        return se;
+
+        return NULL;
+}
+
+int nfc_enable_se(struct nfc_dev *dev, u32 se_idx)
+{
+
+        struct nfc_se *se;
+        int rc;
+
+        pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
+
+        device_lock(&dev->dev);
+
+        if (!device_is_registered(&dev->dev)) {
+                rc = -ENODEV;
+                goto error;
+        }
+
+        if (!dev->dev_up) {
+                rc = -ENODEV;
+                goto error;
+        }
+
+        if (dev->polling) {
+                rc = -EBUSY;
+                goto error;
+        }
+
+        if (!dev->ops->enable_se || !dev->ops->disable_se) {
+                rc = -EOPNOTSUPP;
+                goto error;
+        }
+
+        se = find_se(dev, se_idx);
+        if (!se) {
+                rc = -EINVAL;
+                goto error;
+        }
+
+        if (se->type == NFC_SE_ENABLED) {
+                rc = -EALREADY;
+                goto error;
+        }
+
+        rc = dev->ops->enable_se(dev, se_idx);
+
+error:
+        device_unlock(&dev->dev);
+        return rc;
+}
+
+int nfc_disable_se(struct nfc_dev *dev, u32 se_idx)
+{
+
+        struct nfc_se *se;
+        int rc;
+
+        pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
+
+        device_lock(&dev->dev);
+
+        if (!device_is_registered(&dev->dev)) {
+                rc = -ENODEV;
+                goto error;
+        }
+
+        if (!dev->dev_up) {
+                rc = -ENODEV;
+                goto error;
+        }
+
+        if (!dev->ops->enable_se || !dev->ops->disable_se) {
+                rc = -EOPNOTSUPP;
+                goto error;
+        }
+
+        se = find_se(dev, se_idx);
+        if (!se) {
+                rc = -EINVAL;
+                goto error;
+        }
+
+        if (se->type == NFC_SE_DISABLED) {
+                rc = -EALREADY;
+                goto error;
+        }
+
+        rc = dev->ops->disable_se(dev, se_idx);
+
+error:
+        device_unlock(&dev->dev);
+        return rc;
+}
+
 int nfc_set_remote_general_bytes(struct nfc_dev *dev, u8 *gb, u8 gb_len)
 {
         pr_debug("dev_name=%s gb_len=%d\n", dev_name(&dev->dev), gb_len);
@@ -762,14 +864,14 @@ EXPORT_SYMBOL(nfc_driver_failure);
 
 int nfc_add_se(struct nfc_dev *dev, u32 se_idx, u16 type)
 {
-        struct nfc_se *se, *n;
+        struct nfc_se *se;
         int rc;
 
         pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
 
-        list_for_each_entry_safe(se, n, &dev->secure_elements, list)
-                if (se->idx == se_idx)
-                        return -EALREADY;
+        se = find_se(dev, se_idx);
+        if (se)
+                return -EALREADY;
 
         se = kzalloc(sizeof(struct nfc_se), GFP_KERNEL);
         if (!se)
diff --git a/net/nfc/nfc.h b/net/nfc/nfc.h
index a6aeee094aa4..ee85a1fc1b24 100644
--- a/net/nfc/nfc.h
+++ b/net/nfc/nfc.h
@@ -147,4 +147,7 @@ int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx);
 int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, struct sk_buff *skb,
                       data_exchange_cb_t cb, void *cb_context);
 
+int nfc_enable_se(struct nfc_dev *dev, u32 se_idx);
+int nfc_disable_se(struct nfc_dev *dev, u32 se_idx);
+
 #endif /* __LOCAL_NFC_H */