USB: serial: cp210x: add 8-bit and 32-bit register access functions

cp210x_get_config and cp210x_set_config are cumbersome to use. This change
introduces new register access functions for 8 and 32-bit values, instead
of the above functions.

Signed-off-by: Konstantin Shkolnyy <konstantin.shkolnyy@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
This commit is contained in:
Konstantin Shkolnyy 2016-02-28 15:51:41 -06:00 committed by Johan Hovold
parent 19165b2b10
commit fe1b07e99c

View File

@ -469,6 +469,29 @@ static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req,
return result;
}
/*
* Reads any 32-bit CP210X_ register identified by req.
*/
static int cp210x_read_u32_reg(struct usb_serial_port *port, u8 req, u32 *val)
{
__le32 le32_val;
int err;
err = cp210x_read_reg_block(port, req, &le32_val, sizeof(le32_val));
if (err) {
/*
* FIXME Some callers don't bother to check for error,
* at least give them consistent junk until they are fixed
*/
*val = 0;
return err;
}
*val = le32_to_cpu(le32_val);
return 0;
}
/*
* Reads any 16-bit CP210X_ register identified by req.
*/
@ -482,9 +505,18 @@ static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val)
return err;
*val = le16_to_cpu(le16_val);
return 0;
}
/*
* Reads any 8-bit CP210X_ register identified by req.
*/
static int cp210x_read_u8_reg(struct usb_serial_port *port, u8 req, u8 *val)
{
return cp210x_read_reg_block(port, req, val, sizeof(*val));
}
/*
* Writes any 16-bit CP210X_ register (req) whose value is passed
* entirely in the wValue field of the USB request.
@ -507,6 +539,55 @@ static int cp210x_write_u16_reg(struct usb_serial_port *port, u8 req, u16 val)
return result;
}
/*
* 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)
{
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)
return -ENOMEM;
memcpy(dmabuf, buf, bufsize);
result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
req, REQTYPE_HOST_TO_INTERFACE, 0,
port_priv->bInterfaceNumber, dmabuf, bufsize,
USB_CTRL_SET_TIMEOUT);
kfree(dmabuf);
if (result == bufsize) {
result = 0;
} else {
dev_err(&port->dev, "failed set req 0x%x size %d status: %d\n",
req, bufsize, result);
if (result >= 0)
result = -EPROTO;
}
return result;
}
/*
* Writes any 32-bit CP210X_ register identified by req.
*/
static int cp210x_write_u32_reg(struct usb_serial_port *port, u8 req, u32 val)
{
__le32 le32_val;
le32_val = cpu_to_le32(val);
return cp210x_write_reg_block(port, req, &le32_val, sizeof(le32_val));
}
/*
* Detect CP2108 GET_LINE_CTL bug and activate workaround.
* Write a known good value 0x800, read it back.
@ -708,10 +789,10 @@ 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;
u32 baud;
u16 bits;
cp210x_get_config(port, CP210X_GET_BAUDRATE, &baud, 4);
cp210x_read_u32_reg(port, CP210X_GET_BAUDRATE, &baud);
dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud);
*baudp = baud;
@ -858,8 +939,7 @@ static void cp210x_change_speed(struct tty_struct *tty,
baud = cp210x_quantise_baudrate(baud);
dev_dbg(&port->dev, "%s - setting baud rate to %u\n", __func__, baud);
if (cp210x_set_config(port, CP210X_SET_BAUDRATE, &baud,
sizeof(baud))) {
if (cp210x_write_u32_reg(port, CP210X_SET_BAUDRATE, baud)) {
dev_warn(&port->dev, "failed to set baud rate to %u\n", baud);
if (old_termios)
baud = old_termios->c_ospeed;
@ -1030,10 +1110,10 @@ static void cp210x_dtr_rts(struct usb_serial_port *p, int on)
static int cp210x_tiocmget(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
unsigned int control;
u8 control;
int result;
cp210x_get_config(port, CP210X_GET_MDMSTS, &control, 1);
cp210x_read_u8_reg(port, CP210X_GET_MDMSTS, &control);
result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
|((control & CONTROL_RTS) ? TIOCM_RTS : 0)