[PATCH v5 2/8] Bluetooth: btusb: mediatek: return error code for failed register access

Chris Lu
2024-06-26T02:53:48Z

Update the code to immediately return an error code if accessing a
related register fails. This ensures that our desired logic for
subsequent register operations is maintained and allows us to promptly
catch any unexpected errors.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Chris Lu <chris.lu@mediatek.com>
---
drivers/bluetooth/btusb.c | 114 ++++++++++++++++++++++++++++----------
1 file changed, 84 insertions(+), 30 deletions(-)

diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
index fcdd660add19..8239d9c891e6 100644
--- a/drivers/bluetooth/btusb.c
+++ b/drivers/bluetooth/btusb.c
@@ -3037,47 +3037,98 @@ static int btusb_mtk_subsys_reset(struct hci_dev *hdev, u32 dev_id)
int err;

if (dev_id == 0x7922) {
- btusb_mtk_uhw_reg_read(data, MTK_BT_SUBSYS_RST, &val);
+ err = btusb_mtk_uhw_reg_read(data, MTK_BT_SUBSYS_RST, &val);
+ if (err < 0)
+ return err;
val |= 0x00002020;
- btusb_mtk_uhw_reg_write(data, MTK_BT_SUBSYS_RST, val);
- btusb_mtk_uhw_reg_write(data, MTK_EP_RST_OPT, 0x00010001);
- btusb_mtk_uhw_reg_read(data, MTK_BT_SUBSYS_RST, &val);
+ err = btusb_mtk_uhw_reg_write(data, MTK_BT_SUBSYS_RST, val);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_write(data, MTK_EP_RST_OPT, 0x00010001);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_BT_SUBSYS_RST, &val);
+ if (err < 0)
+ return err;
val |= BIT(0);
- btusb_mtk_uhw_reg_write(data, MTK_BT_SUBSYS_RST, val);
+ err = btusb_mtk_uhw_reg_write(data, MTK_BT_SUBSYS_RST, val);
+ if (err < 0)
+ return err;
msleep(100);
} else if (dev_id == 0x7925) {
- btusb_mtk_uhw_reg_read(data, MTK_BT_RESET_REG_CONNV3, &val);
+ err = btusb_mtk_uhw_reg_read(data, MTK_BT_RESET_REG_CONNV3, &val);
+ if (err < 0)
+ return err;
val |= (1 << 5);
- btusb_mtk_uhw_reg_write(data, MTK_BT_RESET_REG_CONNV3, val);
- btusb_mtk_uhw_reg_read(data, MTK_BT_RESET_REG_CONNV3, &val);
+ err = btusb_mtk_uhw_reg_write(data, MTK_BT_RESET_REG_CONNV3, val);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_BT_RESET_REG_CONNV3, &val);
+ if (err < 0)
+ return err;
val &= 0xFFFF00FF;
+ if (err < 0)
+ return err;
val |= (1 << 13);
- btusb_mtk_uhw_reg_write(data, MTK_BT_RESET_REG_CONNV3, val);
- btusb_mtk_uhw_reg_write(data, MTK_EP_RST_OPT, 0x00010001);
- btusb_mtk_uhw_reg_read(data, MTK_BT_RESET_REG_CONNV3, &val);
+ err = btusb_mtk_uhw_reg_write(data, MTK_BT_RESET_REG_CONNV3, val);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_write(data, MTK_EP_RST_OPT, 0x00010001);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_BT_RESET_REG_CONNV3, &val);
+ if (err < 0)
+ return err;
val |= (1 << 0);
- btusb_mtk_uhw_reg_write(data, MTK_BT_RESET_REG_CONNV3, val);
- btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT, 0x000000FF);
- btusb_mtk_uhw_reg_read(data, MTK_UDMA_INT_STA_BT, &val);
- btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT1, 0x000000FF);
- btusb_mtk_uhw_reg_read(data, MTK_UDMA_INT_STA_BT1, &val);
+ err = btusb_mtk_uhw_reg_write(data, MTK_BT_RESET_REG_CONNV3, val);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT, 0x000000FF);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_UDMA_INT_STA_BT, &val);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT1, 0x000000FF);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_UDMA_INT_STA_BT1, &val);
+ if (err < 0)
+ return err;
msleep(100);
} else {
/* It's Device EndPoint Reset Option Register */
bt_dev_dbg(hdev, "Initiating reset mechanism via uhw");
- btusb_mtk_uhw_reg_write(data, MTK_EP_RST_OPT, MTK_EP_RST_IN_OUT_OPT);
- btusb_mtk_uhw_reg_read(data, MTK_BT_WDT_STATUS, &val);
-
+ err = btusb_mtk_uhw_reg_write(data, MTK_EP_RST_OPT, MTK_EP_RST_IN_OUT_OPT);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_BT_WDT_STATUS, &val);
+ if (err < 0)
+ return err;
/* Reset the bluetooth chip via USB interface. */
- btusb_mtk_uhw_reg_write(data, MTK_BT_SUBSYS_RST, 1);
- btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT, 0x000000FF);
- btusb_mtk_uhw_reg_read(data, MTK_UDMA_INT_STA_BT, &val);
- btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT1, 0x000000FF);
- btusb_mtk_uhw_reg_read(data, MTK_UDMA_INT_STA_BT1, &val);
+ err = btusb_mtk_uhw_reg_write(data, MTK_BT_SUBSYS_RST, 1);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT, 0x000000FF);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_UDMA_INT_STA_BT, &val);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT1, 0x000000FF);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_UDMA_INT_STA_BT1, &val);
+ if (err < 0)
+ return err;
/* MT7921 need to delay 20ms between toggle reset bit */
msleep(20);
- btusb_mtk_uhw_reg_write(data, MTK_BT_SUBSYS_RST, 0);
- btusb_mtk_uhw_reg_read(data, MTK_BT_SUBSYS_RST, &val);
+ err = btusb_mtk_uhw_reg_write(data, MTK_BT_SUBSYS_RST, 0);
+ if (err < 0)
+ return err;
+ err = btusb_mtk_uhw_reg_read(data, MTK_BT_SUBSYS_RST, &val);
+ if (err < 0)
+ return err;
}

err = readx_poll_timeout(btusb_mtk_reset_done, hdev, val,
@@ -3085,11 +3136,14 @@ static int btusb_mtk_subsys_reset(struct hci_dev *hdev, u32 dev_id)
if (err < 0)
bt_dev_err(hdev, "Reset timeout");

- if (dev_id == 0x7922)
- btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT, 0x000000FF);
+ if (dev_id == 0x7922) {
+ err = btusb_mtk_uhw_reg_write(data, MTK_UDMA_INT_STA_BT, 0x000000FF);
+ if (err < 0)
+ return err;
+ }

- btusb_mtk_id_get(data, 0x70010200, &val);
- if (!val)
+ err = btusb_mtk_id_get(data, 0x70010200, &val);
+ if (err < 0 || !val)
bt_dev_err(hdev, "Can't get device id, subsys reset fail.");

return err;
--
2.18.0