[PATCH v3] rtl8xxxu: add bluetooth co-existence support for single antenna

From: Chris Chiu
Date: Sat Oct 05 2019 - 05:48:40 EST


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 <chiu@xxxxxxxxxxxx>
---

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