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: Konstantin Shkolnyy <konstantin.shkolnyy@gmail.com>
[johan: minor style change ]
Signed-off-by: Johan Hovold <johan@kernel.org>

diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c
index 666e4c562d881982409bbbf88b4837cb9169040a..c7405928dfcdc360a396f24c63c4d9f406eea504 100644 (file)
--- a/drivers/usb/serial/cp210x.c
+++ b/drivers/usb/serial/cp210x.c
@@ -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));
        }
 
 }