[PATCH v2] Bluetooth: btmtksdio: Add in-band wakeup support

[sean.wang at mediatek.com]

From: Sean Wang <sean.wang at mediatek.com>

Commit ce64b3e94919 ("Bluetooth: mt7921s: Support wake on bluetooth")
adds the wake on bluethooth via a dedicated GPIO.

Extend the wake-on-bluetooth to use the SDIO DAT1 pin (in-band wakeup),
when supported by the SDIO host driver.

Co-developed-by: Yake Yang <yake.yang at mediatek.com>
Signed-off-by: Yake Yang <yake.yang at mediatek.com>
Signed-off-by: Sean Wang <sean.wang at mediatek.com>
---
v2: enhance the patch description and comments
---
 drivers/bluetooth/btmtksdio.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/bluetooth/btmtksdio.c b/drivers/bluetooth/btmtksdio.c
index d6700efcfe8c..9d79c9107b3a 100644
--- a/drivers/bluetooth/btmtksdio.c
+++ b/drivers/bluetooth/btmtksdio.c
@@ -118,6 +118,7 @@ MODULE_DEVICE_TABLE(sdio, btmtksdio_table);
 #define BTMTKSDIO_FUNC_ENABLED		3
 #define BTMTKSDIO_PATCH_ENABLED		4
 #define BTMTKSDIO_HW_RESET_ACTIVE	5
+#define BTMTKSDIO_INBAND_WAKEUP		6
 
 struct mtkbtsdio_hdr {
 	__le16	len;
@@ -1294,6 +1295,9 @@ static bool btmtksdio_sdio_wakeup(struct hci_dev *hdev)
 		.wakeup_delay = cpu_to_le16(0x20),
 	};
 
+	if (test_bit(BTMTKSDIO_INBAND_WAKEUP, &bdev->tx_state))
+		return may_wakeup;
+
 	if (may_wakeup && bdev->data->chipid == 0x7921) {
 		struct sk_buff *skb;
 
@@ -1384,6 +1388,10 @@ static int btmtksdio_probe(struct sdio_func *func,
 	 */
 	pm_runtime_put_noidle(bdev->dev);
 
+	/* Mark if MMC host supports wake on bluetooth by SDIO */
+	if (device_can_wakeup(func->card->host->parent))
+		set_bit(BTMTKSDIO_INBAND_WAKEUP, &bdev->tx_state);
+
 	err = device_init_wakeup(bdev->dev, true);
 	if (err)
 		bt_dev_err(hdev, "failed to initialize device wakeup");
-- 
2.25.1