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author | Konstantin Shkolnyy <konstantin.shkolnyy@gmail.com> | 2016-02-28 21:51:41 (GMT) |
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committer | Johan Hovold <johan@kernel.org> | 2016-02-29 18:04:49 (GMT) |
commit | fe1b07e99ce572a870711d4c989baf031468093b (patch) | |
tree | 903bfbdad3b8d34d4dd2c696331b78ef7937286d /drivers/usb/serial | |
parent | 19165b2b10a3b3d18b32a6add465379deade0736 (diff) | |
download | linux-fe1b07e99ce572a870711d4c989baf031468093b.tar.xz |
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>
Diffstat (limited to 'drivers/usb/serial')
-rw-r--r-- | drivers/usb/serial/cp210x.c | 92 |
1 files changed, 86 insertions, 6 deletions
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index e9b2bdd..666e4c5 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -470,6 +470,29 @@ static int cp210x_read_reg_block(struct usb_serial_port *port, u8 req, } /* + * 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. */ static int cp210x_read_u16_reg(struct usb_serial_port *port, u8 req, u16 *val) @@ -482,10 +505,19 @@ 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. */ @@ -508,6 +540,55 @@ 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) +{ + 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. * If it comes back swapped the bug is detected. @@ -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) |