From: Wang Sheng Long <shenglong.wang.ext@xxxxxxxxxxx>
The cp210x driver lacks soft-flow function,so need and
this function.
Signed-off-by: Wang Sheng Long <shenglong.wang.ext@xxxxxxxxxxx>
---
drivers/usb/serial/cp210x.c | 110 +++++++++++++++++++++++++++++++++---
1 file changed, 103 insertions(+), 7 deletions(-)
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index e732949f65..ad5db0e2ae 100644
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -380,6 +380,9 @@ static struct usb_serial_driver * const serial_drivers[] = {
#define CP210X_PARTNUM_CP2102N_QFN20 0x22
#define CP210X_PARTNUM_UNKNOWN 0xFF
+#define CP210X_VSTART 0x11
+#define CP210X_VSTOP 0x13
+
/* CP210X_GET_COMM_STATUS returns these 0x13 bytes */
struct cp210x_comm_status {
__le32 ulErrors;
@@ -391,6 +394,15 @@ struct cp210x_comm_status {
u8 bReserved;
} __packed;
+struct cp210x_chars_respones{
+ u8 bEofchar;
+ u8 bErrochar;
+ u8 bBreakchar;
+ u8 bEventchar;
+ u8 bXonchar;
+ u8 bXoffchar;
+} __packed;
+
/*
* CP210X_PURGE - 16 bits passed in wValue of USB request.
* SiLabs app note AN571 gives a strange description of the 4 bits:
@@ -624,6 +636,43 @@ static int cp210x_read_vendor_block(struct usb_serial *serial, u8 type, u16 val,
return result;
}
+/*
+ * Read and Write Characrters Respones operate
+ * Register SET_CHARS/GET_CHATS
+ */
+static int cp210x_operate_chars_block(struct usb_serial_port *port, u8 req, u8 type,
+ void *buf, int bufsize)
+{
+ struct usb_serial *serial = port->serial;
+ struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
+ void *dmabuf;
+ int result;
+
+ dmabuf = kmemdup(buf, bufsize, GFP_KERNEL);
+ if (!dmabuf)
+ return -ENOMEM;
+
+ result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
+ req, type, 0, port_priv->bInterfaceNumber, dmabuf, bufsize,
+ USB_CTRL_SET_TIMEOUT);
+ if (result == bufsize) {
+ if (type == REQTYPE_DEVICE_TO_HOST)
+ memcpy(buf, dmabuf, bufsize);
+
+ result = 0;
+ } else {
+ dev_err(&port->dev, "failed get req 0x%x size %d status: %d\n",
+ req, bufsize, result);
+ if (result >= 0)
+ result = -EIO;
+
+ }
+
+ kfree(dmabuf);
+
+ return result;
+}
+
/*
* Writes any 16-bit CP210X_ register (req) whose value is passed
* entirely in the wValue field of the USB request.
@@ -650,8 +699,8 @@ static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
* Writes a variable-sized block of CP210X_ registers, identified by req.
* Data in buf must be in native USB byte order.
*/
-static int cp210x_write_reg_block(struct usb_serial_port *port, u8 req,
- void *buf, int bufsize)
+static int cp210x_write_reg_block(struct usb_serial_port *port,
+ u8 req, void *buf, int bufsize)
{
struct usb_serial *serial = port->serial;
struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);
@@ -1134,11 +1183,17 @@ static void cp210x_set_termios(struct tty_struct *tty,
struct usb_serial_port *port, struct ktermios *old_termios)
{
struct device *dev = &port->dev;
- unsigned int cflag, old_cflag;
+ struct cp210x_chars_respones CharsRes;
+ struct cp210x_flow_ctl flow_ctl;
+ unsigned int cflag, old_cflag, iflag;
u16 bits;
+ int result;
+ u32 ctl_hs;
+ u32 flow_repl;
cflag = tty->termios.c_cflag;
old_cflag = old_termios->c_cflag;
+ iflag = tty->termios.c_iflag;
if (tty->termios.c_ospeed != old_termios->c_ospeed)
cp210x_change_speed(tty, port, old_termios);
@@ -1212,10 +1267,6 @@ static void cp210x_set_termios(struct tty_struct *tty,
}
if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
- struct cp210x_flow_ctl flow_ctl;
- u32 ctl_hs;
- u32 flow_repl;
-
cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl,
sizeof(flow_ctl));
ctl_hs = le32_to_cpu(flow_ctl.ulControlHandshake);
@@ -1252,6 +1303,51 @@ static void cp210x_set_termios(struct tty_struct *tty,
sizeof(flow_ctl));
}
+ /* Set Software Flow Control
+ * Xon/Xoff code
+ * Check the IXOFF/IXON status in the iflag component of the
+ * termios structure.
+ *
+ */
+ if ((iflag & IXOFF) || (iflag & IXON)) {
+ /*set vstart/vstop chars */
+ result = cp210x_operate_chars_block(port, CP210X_GET_CHARS,
+ REQTYPE_DEVICE_TO_HOST, &CharsRes, sizeof(CharsRes));
+ dev_dbg(dev, "%s - bXonchar=0x%x bXoffchar=0x%x \n",
+ __func__, CharsRes.bXonchar, CharsRes.bXoffchar);
+ if (result < 0) {
+ dev_err(dev, "Read Characrters Respones failed "
+ "xon/xoff software flow control\n");
+ return;
+ }
+ CharsRes.bXonchar = CP210X_VSTART;
+ CharsRes.bXoffchar = CP210X_VSTOP;
+ result = cp210x_operate_chars_block(port, CP210X_SET_CHARS,
+ REQTYPE_HOST_TO_INTERFACE, &CharsRes, sizeof(CharsRes));
+ if (result < 0) {
+ memset(&CharsRes, 0, sizeof(CharsRes));
+ dev_err(dev, "Write Characrters Respones failed"
+ "xon/xoff software flow control\n");
+ return;
+ }
+ /*Set Rx/Tx Flow Contrl Flag in ulFlowReplace*/
+ cp210x_read_reg_block(port, CP210X_GET_FLOW, &flow_ctl, sizeof(flow_ctl));
+ flow_repl = le32_to_cpu(flow_ctl.ulFlowReplace);
+ dev_dbg(dev, "%s - read ulControlHandshake=0x%08x, ulFlowReplace=0x%08x\n",
+ __func__, ctl_hs, flow_repl);
+ if (iflag & IXOFF)
+ flow_repl |= CP210X_SERIAL_AUTO_RECEIVE;
+ else
+ flow_repl &= ~CP210X_SERIAL_AUTO_RECEIVE;
+
+ if (iflag & IXON)
+ flow_repl |= CP210X_SERIAL_AUTO_TRANSMIT;
+ else
+ flow_repl &= ~CP210X_SERIAL_AUTO_TRANSMIT;
+
+ flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl);
+ cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl, sizeof(flow_ctl));
+ }
}
static int cp210x_tiocmset(struct tty_struct *tty,
--
2.17.1
