usb: pl2303: move the two baud rate encoding methods to separate functions
Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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@ -269,30 +269,18 @@ static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
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return retval;
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}
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static void pl2303_encode_baudrate(struct tty_struct *tty,
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struct usb_serial_port *port,
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static int pl2303_baudrate_encode_direct(int baud, enum pl2303_type type,
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u8 buf[4])
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{
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struct usb_serial *serial = port->serial;
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struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
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int baud;
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baud = tty_get_baud_rate(tty);
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dev_dbg(&port->dev, "baud requested = %d\n", baud);
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if (!baud)
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return;
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if (spriv->type != HX || baud <= 115200) {
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/*
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* NOTE: Only the values defined in baud_sup are supported !
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* => if unsupported values are set, the PL2303 seems to
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* use 9600 baud (at least my PL2303X always does)
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*/
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const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400,
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3600, 4800, 7200, 9600, 14400, 19200,
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28800, 38400, 57600, 115200, 230400,
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460800, 614400, 921600, 1228800,
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2457600, 3000000, 6000000 };
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const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400, 3600,
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4800, 7200, 9600, 14400, 19200, 28800, 38400,
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57600, 115200, 230400, 460800, 614400, 921600,
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1228800, 2457600, 3000000, 6000000 };
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int i;
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/* Set baudrate to nearest supported value */
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@ -300,27 +288,28 @@ static void pl2303_encode_baudrate(struct tty_struct *tty,
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if (baud_sup[i] > baud)
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break;
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}
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if (i == ARRAY_SIZE(baud_sup))
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baud = baud_sup[i - 1];
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else if (i > 0
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&& (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
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else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
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baud = baud_sup[i - 1];
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else
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baud = baud_sup[i];
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/* type_0, type_1 only support up to 1228800 baud */
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if (spriv->type != HX)
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if (type != HX)
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baud = min_t(int, baud, 1228800);
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/* Direct (standard) baud rate encoding method */
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put_unaligned_le32(baud, buf);
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} else {
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return baud;
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}
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static int pl2303_baudrate_encode_divisor(int baud, enum pl2303_type type,
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u8 buf[4])
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{
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/*
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* Divisor based baud rate encoding method
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*
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* NOTE: it's not clear if the type_0/1 chips
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* support this method
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* NOTE: it's not clear if the type_0/1 chips support this method
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*
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* divisor = 12MHz * 32 / baudrate = 2^A * B
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*
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@ -337,7 +326,7 @@ static void pl2303_encode_baudrate(struct tty_struct *tty,
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/* Respect the specified baud rate limits */
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baud = max_t(int, baud, 75);
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if (spriv->type == HX)
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if (type == HX)
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baud = min_t(int, baud, 6000000);
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else
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baud = min_t(int, baud, 1228800);
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@ -376,8 +365,32 @@ static void pl2303_encode_baudrate(struct tty_struct *tty,
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if (B <= 8)
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B = 512;
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baud = 12000000 * 32 / ((1 << A) * B);
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}
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return baud;
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}
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static void pl2303_encode_baudrate(struct tty_struct *tty,
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struct usb_serial_port *port,
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enum pl2303_type type,
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u8 buf[4])
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{
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int baud;
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baud = tty_get_baud_rate(tty);
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dev_dbg(&port->dev, "baud requested = %d\n", baud);
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if (!baud)
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return;
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/*
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* There are two methods for setting/encoding the baud rate
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* 1) Direct method: encodes the baud rate value directly
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* => supported by all chip types
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* 2) Divisor based method: encodes a divisor to a base value (12MHz*32)
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* => supported by HX chips (and likely not by type_0/1 chips)
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*/
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if (type != HX || baud <= 115200)
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baud = pl2303_baudrate_encode_direct(baud, type, buf);
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else
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baud = pl2303_baudrate_encode_divisor(baud, type, buf);
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/* Save resulting baud rate */
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tty_encode_baud_rate(tty, baud, baud);
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dev_dbg(&port->dev, "baud set = %d\n", baud);
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@ -434,8 +447,8 @@ static void pl2303_set_termios(struct tty_struct *tty,
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dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
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}
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/* For reference buf[0]:buf[3] baud rate value */
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pl2303_encode_baudrate(tty, port, &buf[0]);
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/* For reference: buf[0]:buf[3] baud rate value */
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pl2303_encode_baudrate(tty, port, spriv->type, buf);
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/* For reference buf[4]=0 is 1 stop bits */
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/* For reference buf[4]=1 is 1.5 stop bits */
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