Commit 19165b2b authored by Konstantin Shkolnyy's avatar Konstantin Shkolnyy Committed by Johan Hovold
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USB: serial: cp210x: add 16-bit register access functions 



cp210x_get_config and cp210x_set_config are cumbersome to use. This change
introduces new register access functions for 16-bit values, instead of
the above functions.

Signed-off-by: default avatarKonstantin Shkolnyy <konstantin.shkolnyy@gmail.com>
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
parent 6424839c

drivers/usb/serial/cp210x.c

+108 −39
Original line number Diff line number Diff line
@@ -423,14 +423,88 @@ static int cp210x_set_config(struct usb_serial_port *port, u8 request, 
}



/*

 * cp210x_set_config_single

 * Convenience function for calling cp210x_set_config on single data values

 * without requiring an integer pointer

 * Reads a variable-sized block of CP210X_ registers, identified by req.

 * Returns data into buf in native USB byte order.

 */

static inline int cp210x_set_config_single(struct usb_serial_port *port,

		u8 request, unsigned int data)

static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,

		void *buf, int bufsize)

{

	return cp210x_set_config(port, request, &data, 2);

	struct usb_serial *serial = port->serial;

	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);

	void *dmabuf;

	int result;



	dmabuf = kmalloc(bufsize, GFP_KERNEL);

	if (!dmabuf) {

		/*

		 * FIXME Some callers don't bother to check for error,

		 * at least give them consistent junk until they are fixed

		 */

		memset(buf, 0, bufsize);

		return -ENOMEM;

	}



	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),

			req, REQTYPE_INTERFACE_TO_HOST, 0,

			port_priv->bInterfaceNumber, dmabuf, bufsize,

			USB_CTRL_SET_TIMEOUT);

	if (result == bufsize) {

		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 = -EPROTO;



		/*

		 * FIXME Some callers don't bother to check for error,

		 * at least give them consistent junk until they are fixed

		 */

		memset(buf, 0, bufsize);

	}



	kfree(dmabuf);



	return result;

}



/*

 * Reads any 16-bit CP210X_ register identified by req.

 */

static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)

{

	__le16 le16_val;

	int err;



	err = cp210x_read_reg_block(port, req, &le16_val, sizeof(le16_val));

	if (err)

		return err;



	*val = le16_to_cpu(le16_val);

	return 0;

}



/*

 * Writes any 16-bit CP210X_ register (req) whose value is passed

 * entirely in the wValue field of the USB request.

 */

static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)

{

	struct usb_serial *serial = port->serial;

	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);

	int result;



	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),

			req, REQTYPE_HOST_TO_INTERFACE, val,

			port_priv->bInterfaceNumber, NULL, 0,

			USB_CTRL_SET_TIMEOUT);

	if (result < 0) {

		dev_err(&port->dev, "failed set request 0x%x status: %d\n",

				req, result);

	}



	return result;

}



/*
@@ -442,47 +516,46 @@ static inline int cp210x_set_config_single(struct usb_serial_port *port, 
static int cp210x_detect_swapped_line_ctl(struct usb_serial_port *port)

{

	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);

	unsigned int line_ctl_save;

	unsigned int line_ctl_test;

	u16 line_ctl_save;

	u16 line_ctl_test;

	int err;



	err = cp210x_get_config(port, CP210X_GET_LINE_CTL, &line_ctl_save, 2);

	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_save);

	if (err)

		return err;



	line_ctl_test = 0x800;

	err = cp210x_set_config(port, CP210X_SET_LINE_CTL, &line_ctl_test, 2);

	err = cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, 0x800);

	if (err)

		return err;



	err = cp210x_get_config(port, CP210X_GET_LINE_CTL, &line_ctl_test, 2);

	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, &line_ctl_test);

	if (err)

		return err;



	if (line_ctl_test == 8) {

		port_priv->has_swapped_line_ctl = true;

		line_ctl_save = swab16((u16)line_ctl_save);

		line_ctl_save = swab16(line_ctl_save);

	}



	return cp210x_set_config(port, CP210X_SET_LINE_CTL, &line_ctl_save, 2);

	return cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, line_ctl_save);

}



/*

 * Must always be called instead of cp210x_get_config(CP210X_GET_LINE_CTL)

 * Must always be called instead of cp210x_read_u16_reg(CP210X_GET_LINE_CTL)

 * to workaround cp2108 bug and get correct value.

 */

static int cp210x_get_line_ctl(struct usb_serial_port *port, unsigned int *ctl)

static int cp210x_get_line_ctl(struct usb_serial_port *port, u16 *ctl)

{

	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);

	int err;



	err = cp210x_get_config(port, CP210X_GET_LINE_CTL, ctl, 2);

	err = cp210x_read_u16_reg(port, CP210X_GET_LINE_CTL, ctl);

	if (err)

		return err;



	/* Workaround swapped bytes in 16-bit value from CP210X_GET_LINE_CTL */

	if (port_priv->has_swapped_line_ctl)

		*ctl = swab16((u16)(*ctl));

		*ctl = swab16(*ctl);



	return 0;

}
@@ -533,8 +606,7 @@ static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port) 
{

	int result;



	result = cp210x_set_config_single(port, CP210X_IFC_ENABLE,

								UART_ENABLE);

	result = cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_ENABLE);

	if (result) {

		dev_err(&port->dev, "%s - Unable to enable UART\n", __func__);

		return result;
@@ -552,15 +624,12 @@ static int cp210x_open(struct tty_struct *tty, struct usb_serial_port *port) 


static void cp210x_close(struct usb_serial_port *port)

{

	unsigned int purge_ctl;



	usb_serial_generic_close(port);



	/* Clear both queues; cp2108 needs this to avoid an occasional hang */

	purge_ctl = PURGE_ALL;

	cp210x_set_config(port, CP210X_PURGE, &purge_ctl, 2);

	cp210x_write_u16_reg(port, CP210X_PURGE, PURGE_ALL);



	cp210x_set_config_single(port, CP210X_IFC_ENABLE, UART_DISABLE);

	cp210x_write_u16_reg(port, CP210X_IFC_ENABLE, UART_DISABLE);

}



/*
@@ -640,7 +709,7 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, 
	struct device *dev = &port->dev;

	unsigned int cflag, modem_ctl[4];

	unsigned int baud;

	unsigned int bits;

	u16 bits;



	cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
@@ -673,14 +742,14 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, 
		cflag |= CS8;

		bits &= ~BITS_DATA_MASK;

		bits |= BITS_DATA_8;

		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);

		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);

		break;

	default:

		dev_dbg(dev, "%s - Unknown number of data bits, using 8\n", __func__);

		cflag |= CS8;

		bits &= ~BITS_DATA_MASK;

		bits |= BITS_DATA_8;

		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);

		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);

		break;

	}
@@ -711,7 +780,7 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, 
		dev_dbg(dev, "%s - Unknown parity mode, disabling parity\n", __func__);

		cflag &= ~PARENB;

		bits &= ~BITS_PARITY_MASK;

		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);

		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);

		break;

	}
@@ -723,7 +792,7 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, 
	case BITS_STOP_1_5:

		dev_dbg(dev, "%s - stop bits = 1.5 (not supported, using 1 stop bit)\n", __func__);

		bits &= ~BITS_STOP_MASK;

		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);

		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);

		break;

	case BITS_STOP_2:

		dev_dbg(dev, "%s - stop bits = 2\n", __func__);
@@ -732,7 +801,7 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, 
	default:

		dev_dbg(dev, "%s - Unknown number of stop bits, using 1 stop bit\n", __func__);

		bits &= ~BITS_STOP_MASK;

		cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2);

		cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits);

		break;

	}
@@ -806,7 +875,7 @@ static void cp210x_set_termios(struct tty_struct *tty, 
{

	struct device *dev = &port->dev;

	unsigned int cflag, old_cflag;

	unsigned int bits;

	u16 bits;

	unsigned int modem_ctl[4];



	cflag = tty->termios.c_cflag;
@@ -845,7 +914,7 @@ static void cp210x_set_termios(struct tty_struct *tty, 
			bits |= BITS_DATA_8;

			break;

		}

		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))

		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))

			dev_dbg(dev, "Number of data bits requested not supported by device\n");

	}
@@ -872,7 +941,7 @@ static void cp210x_set_termios(struct tty_struct *tty, 
				}

			}

		}

		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))

		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))

			dev_dbg(dev, "Parity mode not supported by device\n");

	}
@@ -886,7 +955,7 @@ static void cp210x_set_termios(struct tty_struct *tty, 
			bits |= BITS_STOP_1;

			dev_dbg(dev, "%s - stop bits = 1\n", __func__);

		}

		if (cp210x_set_config(port, CP210X_SET_LINE_CTL, &bits, 2))

		if (cp210x_write_u16_reg(port, CP210X_SET_LINE_CTL, bits))

			dev_dbg(dev, "Number of stop bits requested not supported by device\n");

	}
@@ -926,7 +995,7 @@ static int cp210x_tiocmset(struct tty_struct *tty, 
static int cp210x_tiocmset_port(struct usb_serial_port *port,

		unsigned int set, unsigned int clear)

{

	unsigned int control = 0;

	u16 control = 0;



	if (set & TIOCM_RTS) {

		control |= CONTROL_RTS;
@@ -947,7 +1016,7 @@ static int cp210x_tiocmset_port(struct usb_serial_port *port, 


	dev_dbg(&port->dev, "%s - control = 0x%.4x\n", __func__, control);



	return cp210x_set_config(port, CP210X_SET_MHS, &control, 2);

	return cp210x_write_u16_reg(port, CP210X_SET_MHS, control);

}



static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
@@ -981,7 +1050,7 @@ static int cp210x_tiocmget(struct tty_struct *tty) 
static void cp210x_break_ctl(struct tty_struct *tty, int break_state)

{

	struct usb_serial_port *port = tty->driver_data;

	unsigned int state;

	u16 state;



	if (break_state == 0)

		state = BREAK_OFF;
@@ -989,7 +1058,7 @@ static void cp210x_break_ctl(struct tty_struct *tty, int break_state) 
		state = BREAK_ON;

	dev_dbg(&port->dev, "%s - turning break %s\n", __func__,

		state == BREAK_OFF ? "off" : "on");

	cp210x_set_config(port, CP210X_SET_BREAK, &state, 2);

	cp210x_write_u16_reg(port, CP210X_SET_BREAK, state);

}



static int cp210x_port_probe(struct usb_serial_port *port)