[PATCH v3 2/3] staging: r8188eu: Shorten calls chain of rtw_read8/16/32()

["Fabio M. De Francesco" <fmdefrancesco@xxxxxxxxx>]

Shorten the calls chain of rtw_read8/16/32() down to the actual reads.
For this purpose unify the three usb_read8/16/32 into the new
usb_read(); make the latter parameterizable with 'size'; embed most of
the code of usbctrl_vendorreq() into usb_read() and use in it the new
usb_control_msg_recv() API of USB Core.

Suggested-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Co-developed-by: Pavel Skripkin <paskripkin@xxxxxxxxx>
Signed-off-by: Pavel Skripkin <paskripkin@xxxxxxxxx>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@xxxxxxxxx>
---

v2->v3: No changes.

v1->v2: No changes.

 drivers/staging/r8188eu/hal/usb_ops_linux.c | 92 +++++++++++++++++----
 1 file changed, 78 insertions(+), 14 deletions(-)

diff --git a/drivers/staging/r8188eu/hal/usb_ops_linux.c b/drivers/staging/r8188eu/hal/usb_ops_linux.c
index a87b0d2e87d0..f9c4fd5a2c53 100644
--- a/drivers/staging/r8188eu/hal/usb_ops_linux.c
+++ b/drivers/staging/r8188eu/hal/usb_ops_linux.c
@@ -97,38 +97,102 @@ static int usbctrl_vendorreq(struct intf_hdl *pintfhdl, u16 value, void *pdata,
 	return status;
 }
 
+static int usb_read(struct intf_hdl *intfhdl, u32 addr, void *data, u8 size)
+{
+	u16 value = (u16)(addr & 0x0000ffff);
+	struct adapter *adapt = intfhdl->padapter;
+	struct dvobj_priv *dvobjpriv = adapter_to_dvobj(adapt);
+	struct usb_device *udev = dvobjpriv->pusbdev;
+	int status;
+	u8 *io_buf;
+	int vendorreq_times = 0;
+
+	if (adapt->bSurpriseRemoved || adapt->pwrctrlpriv.pnp_bstop_trx) {
+		status = -EPERM;
+		goto exit;
+	}
+
+	mutex_lock(&dvobjpriv->usb_vendor_req_mutex);
+
+	/*  Acquire IO memory for vendorreq */
+	io_buf = dvobjpriv->usb_vendor_req_buf;
+
+	if (!io_buf) {
+		DBG_88E("[%s] io_buf == NULL\n", __func__);
+		status = -ENOMEM;
+		goto release_mutex;
+	}
+
+	while (++vendorreq_times <= MAX_USBCTRL_VENDORREQ_TIMES) {
+		status = usb_control_msg_recv(udev, 0, REALTEK_USB_VENQT_CMD_REQ,
+					      REALTEK_USB_VENQT_READ, value,
+					      REALTEK_USB_VENQT_CMD_IDX, io_buf,
+					      size, RTW_USB_CONTROL_MSG_TIMEOUT,
+					      GFP_KERNEL);
+		if (!status) {   /*  Success this control transfer. */
+			rtw_reset_continual_urb_error(dvobjpriv);
+			memcpy(data, io_buf, size);
+		} else { /*  error cases */
+			DBG_88E("reg 0x%x, usb %s %u fail, status:%d vendorreq_times:%d\n",
+				value, "read", size, status, vendorreq_times);
+
+			if (status == (-ESHUTDOWN) || status == -ENODEV) {
+				adapt->bSurpriseRemoved = true;
+			} else {
+				struct hal_data_8188e *haldata = GET_HAL_DATA(adapt);
+
+				haldata->srestpriv.wifi_error_status = USB_VEN_REQ_CMD_FAIL;
+			}
+
+			if (rtw_inc_and_chk_continual_urb_error(dvobjpriv)) {
+				adapt->bSurpriseRemoved = true;
+				break;
+			}
+		}
+
+		/*  firmware download is checksummed, don't retry */
+		if ((value >= FW_8188E_START_ADDRESS && value <= FW_8188E_END_ADDRESS) || !status)
+			break;
+	}
+
+release_mutex:
+	mutex_unlock(&dvobjpriv->usb_vendor_req_mutex);
+exit:
+	return status;
+}
+
 u8 rtw_read8(struct adapter *adapter, u32 addr)
 {
-	struct io_priv *pio_priv = &adapter->iopriv;
-	struct intf_hdl *pintfhdl = &pio_priv->intf;
-	u16 wvalue = (u16)(addr & 0x0000ffff);
+	struct io_priv *io_priv = &adapter->iopriv;
+	struct intf_hdl *intfhdl = &io_priv->intf;
+	u16 value = (u16)(addr & 0x0000ffff);
 	u8 data;
 
-	usbctrl_vendorreq(pintfhdl, wvalue, &data, 1, REALTEK_USB_VENQT_READ);
+	usb_read(intfhdl, value, &data, 1);
 
 	return data;
 }
 
 u16 rtw_read16(struct adapter *adapter, u32 addr)
 {
-	struct io_priv *pio_priv = &adapter->iopriv;
-	struct intf_hdl *pintfhdl = &pio_priv->intf;
-	u16 wvalue = (u16)(addr & 0x0000ffff);
-	__le32 data;
+	struct io_priv *io_priv = &adapter->iopriv;
+	struct intf_hdl *intfhdl = &io_priv->intf;
+	u16 value = (u16)(addr & 0x0000ffff);
+	__le16 data;
 
-	usbctrl_vendorreq(pintfhdl, wvalue, &data, 2, REALTEK_USB_VENQT_READ);
+	usb_read(intfhdl, value, &data, 2);
 
-	return (u16)(le32_to_cpu(data) & 0xffff);
+	return le16_to_cpu(data);
 }
 
 u32 rtw_read32(struct adapter *adapter, u32 addr)
 {
-	struct io_priv *pio_priv = &adapter->iopriv;
-	struct intf_hdl *pintfhdl = &pio_priv->intf;
-	u16 wvalue = (u16)(addr & 0x0000ffff);
+	struct io_priv *io_priv = &adapter->iopriv;
+	struct intf_hdl *intfhdl = &io_priv->intf;
+	u16 value = (u16)(addr & 0x0000ffff);
 	__le32 data;
 
-	usbctrl_vendorreq(pintfhdl, wvalue, &data, 4, REALTEK_USB_VENQT_READ);
+	usb_read(intfhdl, value, &data, 4);
 
 	return le32_to_cpu(data);
 }
-- 
2.33.0