The RTL8723BU suffers the wifi disconnection problem while bluetooth
device connected. While wifi is doing tx/rx, the bluetooth will scan
without results. This is due to the wifi and bluetooth share the same
single antenna for RF communication and they need to have a mechanism
to collaborate.

BT information is provided via the packet sent from co-processor to
host (C2H). It contains the status of BT but the rtl8723bu_handle_c2h
dose not really handle it. And there's no bluetooth coexistence
mechanism to deal with it.

This commit adds a workqueue to set the tdma configurations and
coefficient table per the parsed bluetooth link status and given
wifi connection state. The tdma/coef table comes from the vendor
driver code of the RTL8192EU and RTL8723BU. However, this commit is
only for single antenna scenario which RTL8192EU is default dual
antenna. The rtl8xxxu_parse_rxdesc24 which invokes the handle_c2h
is only for 8723b and 8192e so the mechanism is expected to work
on both chips with single antenna. Note RTL8192EU dual antenna is
not supported.

Signed-off-by: Chris Chiu <c...@endlessm.com>
---

Notes:
  v2:
   - Add helper functions to replace bunch of tdma settings
   - Reformat some lines to meet kernel coding style
  v3:
   - Add comment for rtl8723bu_set_coex_with_type()


 .../net/wireless/realtek/rtl8xxxu/rtl8xxxu.h  |  37 +++
 .../realtek/rtl8xxxu/rtl8xxxu_8723b.c         |   2 -
 .../wireless/realtek/rtl8xxxu/rtl8xxxu_core.c | 269 +++++++++++++++++-
 3 files changed, 301 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h 
b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h
index 582c2a346cec..22e95b11bfbb 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu.h
@@ -1220,6 +1220,37 @@ enum ratr_table_mode_new {
        RATEID_IDX_BGN_3SS = 14,
 };
 
+#define BT_INFO_8723B_1ANT_B_FTP               BIT(7)
+#define BT_INFO_8723B_1ANT_B_A2DP              BIT(6)
+#define BT_INFO_8723B_1ANT_B_HID               BIT(5)
+#define BT_INFO_8723B_1ANT_B_SCO_BUSY          BIT(4)
+#define BT_INFO_8723B_1ANT_B_ACL_BUSY          BIT(3)
+#define BT_INFO_8723B_1ANT_B_INQ_PAGE          BIT(2)
+#define BT_INFO_8723B_1ANT_B_SCO_ESCO          BIT(1)
+#define BT_INFO_8723B_1ANT_B_CONNECTION        BIT(0)
+
+enum _BT_8723B_1ANT_STATUS {
+       BT_8723B_1ANT_STATUS_NON_CONNECTED_IDLE      = 0x0,
+       BT_8723B_1ANT_STATUS_CONNECTED_IDLE          = 0x1,
+       BT_8723B_1ANT_STATUS_INQ_PAGE                = 0x2,
+       BT_8723B_1ANT_STATUS_ACL_BUSY                = 0x3,
+       BT_8723B_1ANT_STATUS_SCO_BUSY                = 0x4,
+       BT_8723B_1ANT_STATUS_ACL_SCO_BUSY            = 0x5,
+       BT_8723B_1ANT_STATUS_MAX
+};
+
+struct rtl8xxxu_btcoex {
+       u8      bt_status;
+       bool    bt_busy;
+       bool    has_sco;
+       bool    has_a2dp;
+       bool    has_hid;
+       bool    has_pan;
+       bool    hid_only;
+       bool    a2dp_only;
+       bool    c2h_bt_inquiry;
+};
+
 #define RTL8XXXU_RATR_STA_INIT 0
 #define RTL8XXXU_RATR_STA_HIGH 1
 #define RTL8XXXU_RATR_STA_MID  2
@@ -1340,6 +1371,10 @@ struct rtl8xxxu_priv {
         */
        struct ieee80211_vif *vif;
        struct delayed_work ra_watchdog;
+       struct work_struct c2hcmd_work;
+       struct sk_buff_head c2hcmd_queue;
+       spinlock_t c2hcmd_lock;
+       struct rtl8xxxu_btcoex bt_coex;
 };
 
 struct rtl8xxxu_rx_urb {
@@ -1486,6 +1521,8 @@ void rtl8xxxu_fill_txdesc_v2(struct ieee80211_hw *hw, 
struct ieee80211_hdr *hdr,
                             struct rtl8xxxu_txdesc32 *tx_desc32, bool sgi,
                             bool short_preamble, bool ampdu_enable,
                             u32 rts_rate);
+void rtl8723bu_set_ps_tdma(struct rtl8xxxu_priv *priv,
+                          u8 arg1, u8 arg2, u8 arg3, u8 arg4, u8 arg5);
 
 extern struct rtl8xxxu_fileops rtl8192cu_fops;
 extern struct rtl8xxxu_fileops rtl8192eu_fops;
diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723b.c 
b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723b.c
index ceffe05bd65b..9ba661b3d767 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723b.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8723b.c
@@ -1580,9 +1580,7 @@ static void rtl8723b_enable_rf(struct rtl8xxxu_priv *priv)
        /*
         * Software control, antenna at WiFi side
         */
-#ifdef NEED_PS_TDMA
        rtl8723bu_set_ps_tdma(priv, 0x08, 0x00, 0x00, 0x00, 0x00);
-#endif
 
        rtl8xxxu_write32(priv, REG_BT_COEX_TABLE1, 0x55555555);
        rtl8xxxu_write32(priv, REG_BT_COEX_TABLE2, 0x55555555);
diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c 
b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
index bd5ccb3aa5d7..8c47fdf2fdef 100644
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
@@ -3820,9 +3820,8 @@ void rtl8xxxu_power_off(struct rtl8xxxu_priv *priv)
        rtl8xxxu_write8(priv, REG_RSV_CTRL, 0x0e);
 }
 
-#ifdef NEED_PS_TDMA
-static void rtl8723bu_set_ps_tdma(struct rtl8xxxu_priv *priv,
-                                 u8 arg1, u8 arg2, u8 arg3, u8 arg4, u8 arg5)
+void rtl8723bu_set_ps_tdma(struct rtl8xxxu_priv *priv,
+                          u8 arg1, u8 arg2, u8 arg3, u8 arg4, u8 arg5)
 {
        struct h2c_cmd h2c;
 
@@ -3835,7 +3834,6 @@ static void rtl8723bu_set_ps_tdma(struct rtl8xxxu_priv 
*priv,
        h2c.b_type_dma.data5 = arg5;
        rtl8xxxu_gen2_h2c_cmd(priv, &h2c, sizeof(h2c.b_type_dma));
 }
-#endif
 
 void rtl8xxxu_gen2_disable_rf(struct rtl8xxxu_priv *priv)
 {
@@ -5186,12 +5184,265 @@ static void rtl8xxxu_rx_urb_work(struct work_struct 
*work)
        }
 }
 
+/*
+ * The RTL8723BU/RTL8192EU vendor driver use coexistence table type
+ * 0-7 to represent writing different combinations of register values
+ * to REG_BT_COEX_TABLEs. It's for different kinds of coexistence use
+ * cases which Realtek doesn't provide detail for these settings. Keep
+ * this aligned with vendor driver for easier maintenance.
+ */
+void rtl8723bu_set_coex_with_type(struct rtl8xxxu_priv *priv, u8 type)
+{
+       switch (type) {
+       case 0:
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE1, 0x55555555);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE2, 0x55555555);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE3, 0x00ffffff);
+               rtl8xxxu_write8(priv, REG_BT_COEX_TABLE4, 0x03);
+               break;
+       case 1:
+       case 3:
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE1, 0x55555555);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE2, 0x5a5a5a5a);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE3, 0x00ffffff);
+               rtl8xxxu_write8(priv, REG_BT_COEX_TABLE4, 0x03);
+               break;
+       case 2:
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE1, 0x5a5a5a5a);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE2, 0x5a5a5a5a);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE3, 0x00ffffff);
+               rtl8xxxu_write8(priv, REG_BT_COEX_TABLE4, 0x03);
+               break;
+       case 4:
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE1, 0x5a5a5a5a);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE2, 0xaaaa5a5a);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE3, 0x00ffffff);
+               rtl8xxxu_write8(priv, REG_BT_COEX_TABLE4, 0x03);
+               break;
+       case 5:
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE1, 0x5a5a5a5a);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE2, 0xaa5a5a5a);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE3, 0x00ffffff);
+               rtl8xxxu_write8(priv, REG_BT_COEX_TABLE4, 0x03);
+               break;
+       case 6:
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE1, 0x55555555);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE2, 0xaaaaaaaa);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE3, 0x00ffffff);
+               rtl8xxxu_write8(priv, REG_BT_COEX_TABLE4, 0x03);
+               break;
+       case 7:
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE1, 0xaaaaaaaa);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE2, 0xaaaaaaaa);
+               rtl8xxxu_write32(priv, REG_BT_COEX_TABLE3, 0x00ffffff);
+               rtl8xxxu_write8(priv, REG_BT_COEX_TABLE4, 0x03);
+               break;
+       default:
+               break;
+       }
+}
+
+void rtl8723bu_update_bt_link_info(struct rtl8xxxu_priv *priv, u8 bt_info)
+{
+       struct rtl8xxxu_btcoex *btcoex = &priv->bt_coex;
+
+       if (bt_info & BT_INFO_8723B_1ANT_B_INQ_PAGE)
+               btcoex->c2h_bt_inquiry = true;
+       else
+               btcoex->c2h_bt_inquiry = false;
+
+       if (!(bt_info & BT_INFO_8723B_1ANT_B_CONNECTION)) {
+               btcoex->bt_status = BT_8723B_1ANT_STATUS_NON_CONNECTED_IDLE;
+               btcoex->has_sco = false;
+               btcoex->has_hid = false;
+               btcoex->has_pan = false;
+               btcoex->has_a2dp = false;
+       } else {
+               if ((bt_info & 0x1f) == BT_INFO_8723B_1ANT_B_CONNECTION)
+                       btcoex->bt_status = BT_8723B_1ANT_STATUS_CONNECTED_IDLE;
+               else if ((bt_info & BT_INFO_8723B_1ANT_B_SCO_ESCO) ||
+                        (bt_info & BT_INFO_8723B_1ANT_B_SCO_BUSY))
+                       btcoex->bt_status = BT_8723B_1ANT_STATUS_SCO_BUSY;
+               else if (bt_info & BT_INFO_8723B_1ANT_B_ACL_BUSY)
+                       btcoex->bt_status = BT_8723B_1ANT_STATUS_ACL_BUSY;
+               else
+                       btcoex->bt_status = BT_8723B_1ANT_STATUS_MAX;
+
+               if (bt_info & BT_INFO_8723B_1ANT_B_FTP)
+                       btcoex->has_pan = true;
+               else
+                       btcoex->has_pan = false;
+
+               if (bt_info & BT_INFO_8723B_1ANT_B_A2DP)
+                       btcoex->has_a2dp = true;
+               else
+                       btcoex->has_a2dp = false;
+
+               if (bt_info & BT_INFO_8723B_1ANT_B_HID)
+                       btcoex->has_hid = true;
+               else
+                       btcoex->has_hid = false;
+
+               if (bt_info & BT_INFO_8723B_1ANT_B_SCO_ESCO)
+                       btcoex->has_sco = true;
+               else
+                       btcoex->has_sco = false;
+       }
+
+       if (!btcoex->has_a2dp && !btcoex->has_sco &&
+           !btcoex->has_pan && btcoex->has_hid)
+               btcoex->hid_only = true;
+       else
+               btcoex->hid_only = false;
+
+       if (!btcoex->has_sco && !btcoex->has_pan &&
+           !btcoex->has_hid && btcoex->has_a2dp)
+               btcoex->has_a2dp = true;
+       else
+               btcoex->has_a2dp = false;
+
+       if (btcoex->bt_status == BT_8723B_1ANT_STATUS_SCO_BUSY ||
+           btcoex->bt_status == BT_8723B_1ANT_STATUS_ACL_BUSY)
+               btcoex->bt_busy = true;
+       else
+               btcoex->bt_busy = false;
+}
+
+void rtl8723bu_handle_bt_inquiry(struct rtl8xxxu_priv *priv)
+{
+       struct ieee80211_vif *vif;
+       struct rtl8xxxu_btcoex *btcoex;
+       bool wifi_connected;
+
+       vif = priv->vif;
+       btcoex = &priv->bt_coex;
+       wifi_connected = (vif && vif->bss_conf.assoc);
+
+       if (!wifi_connected) {
+               rtl8723bu_set_ps_tdma(priv, 0x8, 0x0, 0x0, 0x0, 0x0);
+               rtl8723bu_set_coex_with_type(priv, 0);
+       } else if (btcoex->has_sco || btcoex->has_hid || btcoex->has_a2dp) {
+               rtl8723bu_set_ps_tdma(priv, 0x61, 0x35, 0x3, 0x11, 0x11);
+               rtl8723bu_set_coex_with_type(priv, 4);
+       } else if (btcoex->has_pan) {
+               rtl8723bu_set_ps_tdma(priv, 0x61, 0x3f, 0x3, 0x11, 0x11);
+               rtl8723bu_set_coex_with_type(priv, 4);
+       } else {
+               rtl8723bu_set_ps_tdma(priv, 0x8, 0x0, 0x0, 0x0, 0x0);
+               rtl8723bu_set_coex_with_type(priv, 7);
+       }
+}
+
+void rtl8723bu_handle_bt_info(struct rtl8xxxu_priv *priv)
+{
+       struct ieee80211_vif *vif;
+       struct rtl8xxxu_btcoex *btcoex;
+       bool wifi_connected;
+
+       vif = priv->vif;
+       btcoex = &priv->bt_coex;
+       wifi_connected = (vif && vif->bss_conf.assoc);
+
+       if (wifi_connected) {
+               u32 val32 = 0;
+               u32 high_prio_tx = 0, high_prio_rx = 0;
+
+               val32 = rtl8xxxu_read32(priv, 0x770);
+               high_prio_tx = val32 & 0x0000ffff;
+               high_prio_rx = (val32  & 0xffff0000) >> 16;
+
+               if (btcoex->bt_busy) {
+                       if (btcoex->hid_only) {
+                               rtl8723bu_set_ps_tdma(priv, 0x61, 0x20,
+                                                     0x3, 0x11, 0x11);
+                               rtl8723bu_set_coex_with_type(priv, 5);
+                       } else if (btcoex->a2dp_only) {
+                               rtl8723bu_set_ps_tdma(priv, 0x61, 0x35,
+                                                     0x3, 0x11, 0x11);
+                               rtl8723bu_set_coex_with_type(priv, 4);
+                       } else if ((btcoex->has_a2dp && btcoex->has_pan) ||
+                                  (btcoex->has_hid && btcoex->has_a2dp &&
+                                   btcoex->has_pan)) {
+                               rtl8723bu_set_ps_tdma(priv, 0x51, 0x21,
+                                                     0x3, 0x10, 0x10);
+                               rtl8723bu_set_coex_with_type(priv, 4);
+                       } else if (btcoex->has_hid && btcoex->has_a2dp) {
+                               rtl8723bu_set_ps_tdma(priv, 0x51, 0x21,
+                                                     0x3, 0x10, 0x10);
+                               rtl8723bu_set_coex_with_type(priv, 3);
+                       } else {
+                               rtl8723bu_set_ps_tdma(priv, 0x61, 0x35,
+                                                     0x3, 0x11, 0x11);
+                               rtl8723bu_set_coex_with_type(priv, 4);
+                       }
+               } else {
+                       rtl8723bu_set_ps_tdma(priv, 0x8, 0x0, 0x0, 0x0, 0x0);
+                       if (high_prio_tx + high_prio_rx <= 60)
+                               rtl8723bu_set_coex_with_type(priv, 2);
+                       else
+                               rtl8723bu_set_coex_with_type(priv, 7);
+               }
+       } else {
+               rtl8723bu_set_ps_tdma(priv, 0x8, 0x0, 0x0, 0x0, 0x0);
+               rtl8723bu_set_coex_with_type(priv, 0);
+       }
+}
+
+static void rtl8xxxu_c2hcmd_callback(struct work_struct *work)
+{
+       struct rtl8xxxu_priv *priv;
+       struct rtl8723bu_c2h *c2h;
+       struct ieee80211_vif *vif;
+       struct device *dev;
+       struct sk_buff *skb = NULL;
+       unsigned long flags;
+       int len;
+       u8 bt_info = 0;
+       struct rtl8xxxu_btcoex *btcoex;
+
+       priv = container_of(work, struct rtl8xxxu_priv, c2hcmd_work);
+       vif = priv->vif;
+       btcoex = &priv->bt_coex;
+       dev = &priv->udev->dev;
+
+       if (priv->rf_paths > 1)
+               goto out;
+
+       while (!skb_queue_empty(&priv->c2hcmd_queue)) {
+               spin_lock_irqsave(&priv->c2hcmd_lock, flags);
+               skb = __skb_dequeue(&priv->c2hcmd_queue);
+               spin_unlock_irqrestore(&priv->c2hcmd_lock, flags);
+
+               c2h = (struct rtl8723bu_c2h *)skb->data;
+               len = skb->len - 2;
+
+               switch (c2h->id) {
+               case C2H_8723B_BT_INFO:
+                       bt_info = c2h->bt_info.bt_info;
+
+                       rtl8723bu_update_bt_link_info(priv, bt_info);
+                       if (btcoex->c2h_bt_inquiry) {
+                               rtl8723bu_handle_bt_inquiry(priv);
+                               break;
+                       }
+                       rtl8723bu_handle_bt_info(priv);
+                       break;
+               default:
+                       break;
+               }
+       }
+
+out:
+       dev_kfree_skb(skb);
+}
+
 static void rtl8723bu_handle_c2h(struct rtl8xxxu_priv *priv,
                                 struct sk_buff *skb)
 {
        struct rtl8723bu_c2h *c2h = (struct rtl8723bu_c2h *)skb->data;
        struct device *dev = &priv->udev->dev;
        int len;
+       unsigned long flags;
 
        len = skb->len - 2;
 
@@ -5229,6 +5480,12 @@ static void rtl8723bu_handle_c2h(struct rtl8xxxu_priv 
*priv,
                               16, 1, c2h->raw.payload, len, false);
                break;
        }
+
+       spin_lock_irqsave(&priv->c2hcmd_lock, flags);
+       __skb_queue_tail(&priv->c2hcmd_queue, skb);
+       spin_unlock_irqrestore(&priv->c2hcmd_lock, flags);
+
+       schedule_work(&priv->c2hcmd_work);
 }
 
 int rtl8xxxu_parse_rxdesc16(struct rtl8xxxu_priv *priv, struct sk_buff *skb)
@@ -5353,7 +5610,6 @@ int rtl8xxxu_parse_rxdesc24(struct rtl8xxxu_priv *priv, 
struct sk_buff *skb)
                struct device *dev = &priv->udev->dev;
                dev_dbg(dev, "%s: C2H packet\n", __func__);
                rtl8723bu_handle_c2h(priv, skb);
-               dev_kfree_skb(skb);
                return RX_TYPE_C2H;
        }
 
@@ -6274,6 +6530,9 @@ static int rtl8xxxu_probe(struct usb_interface *interface,
        spin_lock_init(&priv->rx_urb_lock);
        INIT_WORK(&priv->rx_urb_wq, rtl8xxxu_rx_urb_work);
        INIT_DELAYED_WORK(&priv->ra_watchdog, rtl8xxxu_watchdog_callback);
+       spin_lock_init(&priv->c2hcmd_lock);
+       INIT_WORK(&priv->c2hcmd_work, rtl8xxxu_c2hcmd_callback);
+       skb_queue_head_init(&priv->c2hcmd_queue);
 
        usb_set_intfdata(interface, hw);
 
-- 
2.20.1

Reply via email to