USB: serial: f81534: add auto RTS direction support

#define F81534_DEFAULT_BAUD_RATE	9600

#define F81534_PORT_CONF_RS232		0

#define F81534_PORT_CONF_RS485		BIT(0)

#define F81534_PORT_CONF_RS485_INVERT	(BIT(0) | BIT(1))

#define F81534_PORT_CONF_MODE_MASK	GENMASK(1, 0)

#define F81534_PORT_CONF_DISABLE_PORT	BIT(3)

#define F81534_PORT_CONF_NOT_EXIST_PORT	BIT(7)

#define F81534_PORT_UNAVAILABLE		\

	(F81534_PORT_CONF_DISABLE_PORT | F81534_PORT_CONF_NOT_EXIST_PORT)

#define F81534_1X_RXTRIGGER		0xc3

#define F81534_8X_RXTRIGGER		0xcf

 *			01: 18.46MHz.

 *			10: 24MHz.

 *			11: 14.77MHz.

 * Bit4:	Auto direction(RTS) control (RTS pin Low when TX)

 * Bit5:	Invert direction(RTS) when Bit4 enabled (RTS pin high when TX)

 */

#define F81534_UART_EN			BIT(0)

#define F81534_CLK_24_MHZ		BIT(2)

#define F81534_CLK_14_77_MHZ		(BIT(1) | BIT(2))

#define F81534_CLK_MASK			GENMASK(2, 1)

#define F81534_CLK_RS485_MODE		BIT(4)

#define F81534_CLK_RS485_INVERT		BIT(5)

static const struct usb_device_id f81534_id_table[] = {

	{ USB_DEVICE(FINTEK_VENDOR_ID_1, FINTEK_DEVICE_ID) },

static int f81534_port_probe(struct usb_serial_port *port)

{

	struct f81534_serial_private *serial_priv;

	struct f81534_port_private *port_priv;

	int ret;

	u8 value;

	serial_priv = usb_get_serial_data(port->serial);

	port_priv = devm_kzalloc(&port->dev, sizeof(*port_priv), GFP_KERNEL);

	if (!port_priv)

		return -ENOMEM;

	if (ret)

		return ret;

	value = serial_priv->conf_data[port_priv->phy_num];

	switch (value & F81534_PORT_CONF_MODE_MASK) {

	case F81534_PORT_CONF_RS485_INVERT:

		port_priv->shadow_clk |= F81534_CLK_RS485_MODE |

					F81534_CLK_RS485_INVERT;

		dev_dbg(&port->dev, "RS485 invert mode\n");

		break;

	case F81534_PORT_CONF_RS485:

		port_priv->shadow_clk |= F81534_CLK_RS485_MODE;

		dev_dbg(&port->dev, "RS485 mode\n");

		break;

	default:

	case F81534_PORT_CONF_RS232:

		dev_dbg(&port->dev, "RS232 mode\n");

		break;

	}

	return 0;

}