Commit 7084fa86 authored by Konstantin Shkolnyy's avatar Konstantin Shkolnyy Committed by Johan Hovold
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USB: serial: cp210x: add new access functions for large registers 



cp210x_get_config and cp210x_set_config are cumbersome to use. This change
switches large register access to use new block functions. The old
functions are removed because now they become unused.

Signed-off-by: default avatarKonstantin Shkolnyy <konstantin.shkolnyy@gmail.com>
[johan: minor style change ]
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
parent fe1b07e9

drivers/usb/serial/cp210x.c

+24 −113
Original line number Diff line number Diff line
@@ -323,105 +323,6 @@ struct cp210x_comm_status { 
 */

#define PURGE_ALL		0x000f



/*

 * cp210x_get_config

 * Reads from the CP210x configuration registers

 * 'size' is specified in bytes.

 * 'data' is a pointer to a pre-allocated array of integers large

 * enough to hold 'size' bytes (with 4 bytes to each integer)

 */

static int cp210x_get_config(struct usb_serial_port *port, u8 request,

		unsigned int *data, int size)

{

	struct usb_serial *serial = port->serial;

	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);

	__le32 *buf;

	int result, i, length;



	/* Number of integers required to contain the array */

	length = (((size - 1) | 3) + 1) / 4;



	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);

	if (!buf)

		return -ENOMEM;



	/* Issue the request, attempting to read 'size' bytes */

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

				request, REQTYPE_INTERFACE_TO_HOST, 0x0000,

				port_priv->bInterfaceNumber, buf, size,

				USB_CTRL_GET_TIMEOUT);



	/* Convert data into an array of integers */

	for (i = 0; i < length; i++)

		data[i] = le32_to_cpu(buf[i]);



	kfree(buf);



	if (result != size) {

		dev_dbg(&port->dev, "%s - Unable to send config request, request=0x%x size=%d result=%d\n",

			__func__, request, size, result);

		if (result > 0)

			result = -EPROTO;



		return result;

	}



	return 0;

}



/*

 * cp210x_set_config

 * Writes to the CP210x configuration registers

 * Values less than 16 bits wide are sent directly

 * 'size' is specified in bytes.

 */

static int cp210x_set_config(struct usb_serial_port *port, u8 request,

		unsigned int *data, int size)

{

	struct usb_serial *serial = port->serial;

	struct cp210x_port_private *port_priv = usb_get_serial_port_data(port);

	__le32 *buf;

	int result, i, length;



	/* Number of integers required to contain the array */

	length = (((size - 1) | 3) + 1) / 4;



	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);

	if (!buf)

		return -ENOMEM;



	/* Array of integers into bytes */

	for (i = 0; i < length; i++)

		buf[i] = cpu_to_le32(data[i]);



	if (size > 2) {

		result = usb_control_msg(serial->dev,

				usb_sndctrlpipe(serial->dev, 0),

				request, REQTYPE_HOST_TO_INTERFACE, 0x0000,

				port_priv->bInterfaceNumber, buf, size,

				USB_CTRL_SET_TIMEOUT);

	} else {

		result = usb_control_msg(serial->dev,

				usb_sndctrlpipe(serial->dev, 0),

				request, REQTYPE_HOST_TO_INTERFACE, data[0],

				port_priv->bInterfaceNumber, NULL, 0,

				USB_CTRL_SET_TIMEOUT);

	}



	kfree(buf);



	if ((size > 2 && result != size) || result < 0) {

		dev_dbg(&port->dev, "%s - Unable to send request, request=0x%x size=%d result=%d\n",

			__func__, request, size, result);

		if (result > 0)

			result = -EPROTO;



		return result;

	}



	return 0;

}



/*

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

 * Returns data into buf in native USB byte order.
@@ -788,7 +689,8 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, 
	unsigned int *cflagp, unsigned int *baudp)

{

	struct device *dev = &port->dev;

	unsigned int cflag, modem_ctl[4];

	unsigned int cflag;

	u8 modem_ctl[16];

	u32 baud;

	u16 bits;
@@ -886,8 +788,9 @@ static void cp210x_get_termios_port(struct usb_serial_port *port, 
		break;

	}



	cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);

	if (modem_ctl[0] & 0x0008) {

	cp210x_read_reg_block(port, CP210X_GET_FLOW, modem_ctl,

			sizeof(modem_ctl));

	if (modem_ctl[0] & 0x08) {

		dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);

		cflag |= CRTSCTS;

	} else {
@@ -956,7 +859,7 @@ static void cp210x_set_termios(struct tty_struct *tty, 
	struct device *dev = &port->dev;

	unsigned int cflag, old_cflag;

	u16 bits;

	unsigned int modem_ctl[4];

	u8 modem_ctl[16];



	cflag = tty->termios.c_cflag;

	old_cflag = old_termios->c_cflag;
@@ -1040,27 +943,35 @@ static void cp210x_set_termios(struct tty_struct *tty, 
	}



	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {

		cp210x_get_config(port, CP210X_GET_FLOW, modem_ctl, 16);

		dev_dbg(dev, "%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x\n",

			__func__, modem_ctl[0], modem_ctl[1],

			modem_ctl[2], modem_ctl[3]);



		/* Only bytes 0, 4 and 7 out of first 8 have functional bits */



		cp210x_read_reg_block(port, CP210X_GET_FLOW, modem_ctl,

				sizeof(modem_ctl));

		dev_dbg(dev, "%s - read modem controls = %02x .. .. .. %02x .. .. %02x\n",

			__func__, modem_ctl[0], modem_ctl[4], modem_ctl[7]);



		if (cflag & CRTSCTS) {

			modem_ctl[0] &= ~0x7B;

			modem_ctl[0] |= 0x09;

			modem_ctl[1] = 0x80;

			modem_ctl[4] = 0x80;

			/* FIXME - why clear reserved bits just read? */

			modem_ctl[5] = 0;

			modem_ctl[6] = 0;

			modem_ctl[7] = 0;

			dev_dbg(dev, "%s - flow control = CRTSCTS\n", __func__);

		} else {

			modem_ctl[0] &= ~0x7B;

			modem_ctl[0] |= 0x01;

			modem_ctl[1] |= 0x40;

			/* FIXME - OR here instead of assignment looks wrong */

			modem_ctl[4] |= 0x40;

			dev_dbg(dev, "%s - flow control = NONE\n", __func__);

		}



		dev_dbg(dev, "%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x\n",

			__func__, modem_ctl[0], modem_ctl[1],

			modem_ctl[2], modem_ctl[3]);

		cp210x_set_config(port, CP210X_SET_FLOW, modem_ctl, 16);

		dev_dbg(dev, "%s - write modem controls = %02x .. .. .. %02x .. .. %02x\n",

			__func__, modem_ctl[0], modem_ctl[4], modem_ctl[7]);

		cp210x_write_reg_block(port, CP210X_SET_FLOW, modem_ctl,

				sizeof(modem_ctl));

	}



}

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