From fe1b07e99ce572a870711d4c989baf031468093b Mon Sep 17 00:00:00 2001 From: Konstantin Shkolnyy Date: Sun, 28 Feb 2016 15:51:41 -0600 Subject: [PATCH] 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 Signed-off-by: Johan Hovold --- drivers/usb/serial/cp210x.c | 92 ++++++++++++++++++++++++++++++++++--- 1 file changed, 86 insertions(+), 6 deletions(-) diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index e9b2bddd719f..666e4c562d88 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -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) -- 2.20.1