NFC: digital: Add 'tg_listen_md' and 'tg_get_rf_tech' driver hooks

The digital layer of the NFC subsystem currently
supports a 'tg_listen_mdaa' driver hook that supports
devices that can do mode detection and automatic
anticollision.  However, there are some devices that
can do mode detection but not automatic anitcollision
so add the 'tg_listen_md' hook to support those devices.

In order for the digital layer to get the RF technology
detected by the device from the driver, add the
'tg_get_rf_tech' hook.  It is only valid to call this
hook immediately after a successful call to 'tg_listen_md'.

CC: Thierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

3 files changed, 81 insertions, 9 deletions

diff --git a/net/nfc/digital.h b/net/nfc/digital.h
index 71ad7eefddd4..3c39c72eb038 100644
--- a/net/nfc/digital.h
+++ b/net/nfc/digital.h
@@ -29,6 +29,7 @@
 #define DIGITAL_CMD_TG_SEND        1
 #define DIGITAL_CMD_TG_LISTEN      2
 #define DIGITAL_CMD_TG_LISTEN_MDAA 3
+#define DIGITAL_CMD_TG_LISTEN_MD   4
 
 #define DIGITAL_MAX_HEADER_LEN 7
 #define DIGITAL_CRC_LEN        2
@@ -121,6 +122,8 @@ int digital_tg_send_dep_res(struct nfc_digital_dev *ddev, struct sk_buff *skb);
 
 int digital_tg_listen_nfca(struct nfc_digital_dev *ddev, u8 rf_tech);
 int digital_tg_listen_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech);
+void digital_tg_recv_md_req(struct nfc_digital_dev *ddev, void *arg,
+                            struct sk_buff *resp);
 
 typedef u16 (*crc_func_t)(u16, const u8 *, size_t);
 
diff --git a/net/nfc/digital_core.c b/net/nfc/digital_core.c
index 361bc37d2db1..009bcf317101 100644
--- a/net/nfc/digital_core.c
+++ b/net/nfc/digital_core.c
@@ -201,6 +201,11 @@ static void digital_wq_cmd(struct work_struct *work)
                                                digital_send_cmd_complete, cmd);
                 break;
 
+        case DIGITAL_CMD_TG_LISTEN_MD:
+                rc = ddev->ops->tg_listen_md(ddev, cmd->timeout,
+                                               digital_send_cmd_complete, cmd);
+                break;
+
         default:
                 pr_err("Unknown cmd type %d\n", cmd->type);
                 return;
@@ -293,6 +298,12 @@ static int digital_tg_listen_mdaa(struct nfc_digital_dev *ddev, u8 rf_tech)
                                 500, digital_tg_recv_atr_req, NULL);
 }
 
+static int digital_tg_listen_md(struct nfc_digital_dev *ddev, u8 rf_tech)
+{
+        return digital_send_cmd(ddev, DIGITAL_CMD_TG_LISTEN_MD, NULL, NULL, 500,
+                                digital_tg_recv_md_req, NULL);
+}
+
 int digital_target_found(struct nfc_digital_dev *ddev,
                          struct nfc_target *target, u8 protocol)
 {
@@ -510,6 +521,9 @@ static int digital_start_poll(struct nfc_dev *nfc_dev, __u32 im_protocols,
                 if (ddev->ops->tg_listen_mdaa) {
                         digital_add_poll_tech(ddev, 0,
                                               digital_tg_listen_mdaa);
+                } else if (ddev->ops->tg_listen_md) {
+                        digital_add_poll_tech(ddev, 0,
+                                              digital_tg_listen_md);
                 } else {
                         digital_add_poll_tech(ddev, NFC_DIGITAL_RF_TECH_106A,
                                               digital_tg_listen_nfca);
@@ -737,7 +751,7 @@ struct nfc_digital_dev *nfc_digital_allocate_device(struct nfc_digital_ops *ops,
 
         if (!ops->in_configure_hw || !ops->in_send_cmd || !ops->tg_listen ||
             !ops->tg_configure_hw || !ops->tg_send_cmd || !ops->abort_cmd ||
-            !ops->switch_rf)
+            !ops->switch_rf || (ops->tg_listen_md && !ops->tg_get_rf_tech))
                 return NULL;
 
         ddev = kzalloc(sizeof(struct nfc_digital_dev), GFP_KERNEL);
diff --git a/net/nfc/digital_technology.c b/net/nfc/digital_technology.c
index d276518cc8bf..fb58ed2dd41d 100644
--- a/net/nfc/digital_technology.c
+++ b/net/nfc/digital_technology.c
@@ -1218,33 +1218,48 @@ exit:
         dev_kfree_skb(resp);
 }
 
-int digital_tg_listen_nfca(struct nfc_digital_dev *ddev, u8 rf_tech)
+static int digital_tg_config_nfca(struct nfc_digital_dev *ddev)
 {
         int rc;
 
-        rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
+        rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
+                                     NFC_DIGITAL_RF_TECH_106A);
         if (rc)
                 return rc;
 
-        rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
-                                     NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
+        return digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
+                                       NFC_DIGITAL_FRAMING_NFCA_NFC_DEP);
+}
+
+int digital_tg_listen_nfca(struct nfc_digital_dev *ddev, u8 rf_tech)
+{
+        int rc;
+
+        rc = digital_tg_config_nfca(ddev);
         if (rc)
                 return rc;
 
         return digital_tg_listen(ddev, 300, digital_tg_recv_sens_req, NULL);
 }
 
-int digital_tg_listen_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech)
+static int digital_tg_config_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech)
 {
         int rc;
-        u8 *nfcid2;
 
         rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
         if (rc)
                 return rc;
 
-        rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
-                                     NFC_DIGITAL_FRAMING_NFCF_NFC_DEP);
+        return digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
+                                       NFC_DIGITAL_FRAMING_NFCF_NFC_DEP);
+}
+
+int digital_tg_listen_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech)
+{
+        int rc;
+        u8 *nfcid2;
+
+        rc = digital_tg_config_nfcf(ddev, rf_tech);
         if (rc)
                 return rc;
 
@@ -1258,3 +1273,43 @@ int digital_tg_listen_nfcf(struct nfc_digital_dev *ddev, u8 rf_tech)
 
         return digital_tg_listen(ddev, 300, digital_tg_recv_sensf_req, nfcid2);
 }
+
+void digital_tg_recv_md_req(struct nfc_digital_dev *ddev, void *arg,
+                            struct sk_buff *resp)
+{
+        u8 rf_tech;
+        int rc;
+
+        if (IS_ERR(resp)) {
+                resp = NULL;
+                goto exit_free_skb;
+        }
+
+        rc = ddev->ops->tg_get_rf_tech(ddev, &rf_tech);
+        if (rc)
+                goto exit_free_skb;
+
+        switch (rf_tech) {
+        case NFC_DIGITAL_RF_TECH_106A:
+                rc = digital_tg_config_nfca(ddev);
+                if (rc)
+                        goto exit_free_skb;
+                digital_tg_recv_sens_req(ddev, arg, resp);
+                break;
+        case NFC_DIGITAL_RF_TECH_212F:
+        case NFC_DIGITAL_RF_TECH_424F:
+                rc = digital_tg_config_nfcf(ddev, rf_tech);
+                if (rc)
+                        goto exit_free_skb;
+                digital_tg_recv_sensf_req(ddev, arg, resp);
+                break;
+        default:
+                goto exit_free_skb;
+        }
+
+        return;
+
+exit_free_skb:
+        digital_poll_next_tech(ddev);
+        dev_kfree_skb(resp);
+}