Merge tag 'usb-3.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here is a set of patches that revert all of the changes done to the
  pl2303 USB serial driver in the 3.12-rc timeframe, as it turns out
  they break some devices that work just fine on 3.11.  As it's not a
  good idea to break working systems, drop them all and they will be
  reworked for future kernel versions such that there is no breakage.

  I've also included a MAINTAINERS update for the USB serial subsystem
  and a new device id for the ftdi_sio driver as well"

* tag 'usb-3.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: serial: ftdi_sio: add id for Z3X Box device
  USB: Maintainers change for usb serial drivers
  Revert "USB: pl2303: restrict the divisor based baud rate encoding method to the "HX" chip type"
  Revert "usb: pl2303: fix+improve the divsor based baud rate encoding method"
  Revert "usb: pl2303: do not round to the next nearest standard baud rate for the divisor based baud rate encoding method"
  Revert "usb: pl2303: remove 500000 baud from the list of standard baud rates"
  Revert "usb: pl2303: move the two baud rate encoding methods to separate functions"
  Revert "usb: pl2303: increase the allowed baud rate range for the divisor based encoding method"
  Revert "usb: pl2303: also use the divisor based baud rate encoding method for baud rates < 115200 with HX chips"
  Revert "usb: pl2303: add two comments concerning the supported baud rates with HX chips"
  Revert "pl2303: simplify the else-if contruct for type_1 chips in pl2303_startup()"
  Revert "pl2303: improve the chip type information output on startup"
  Revert "pl2303: improve the chip type detection/distinction"
  Revert "USB: pl2303: distinguish between original and cloned HX chips"

4 files changed, 66 insertions, 268 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 3438384d270c..ffcaf975bed7 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8917,61 +8917,14 @@ W:	http://pegasus2.sourceforge.net/
 S:      Maintained
 F:      drivers/net/usb/rtl8150.c
 
-USB SERIAL BELKIN F5U103 DRIVER
-M:      William Greathouse <wgreathouse@smva.com>
+USB SERIAL SUBSYSTEM
+M:      Johan Hovold <jhovold@gmail.com>
 L:      linux-usb@vger.kernel.org
 S:      Maintained
-F:      drivers/usb/serial/belkin_sa.*
-
-USB SERIAL CYPRESS M8 DRIVER
-M:      Lonnie Mendez <dignome@gmail.com>
-L:      linux-usb@vger.kernel.org
-S:      Maintained
-W:      http://geocities.com/i0xox0i
-W:      http://firstlight.net/cvs
-F:      drivers/usb/serial/cypress_m8.*
-
-USB SERIAL CYBERJACK DRIVER
-M:      Matthias Bruestle and Harald Welte <support@reiner-sct.com>
-W:      http://www.reiner-sct.de/support/treiber_cyberjack.php
-S:      Maintained
-F:      drivers/usb/serial/cyberjack.c
-
-USB SERIAL DIGI ACCELEPORT DRIVER
-M:      Peter Berger <pberger@brimson.com>
-M:      Al Borchers <alborchers@steinerpoint.com>
-L:      linux-usb@vger.kernel.org
-S:      Maintained
-F:      drivers/usb/serial/digi_acceleport.c
-
-USB SERIAL DRIVER
-M:      Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-L:      linux-usb@vger.kernel.org
-S:      Supported
 F:      Documentation/usb/usb-serial.txt
-F:      drivers/usb/serial/generic.c
-F:      drivers/usb/serial/usb-serial.c
+F:      drivers/usb/serial/
 F:      include/linux/usb/serial.h
 
-USB SERIAL EMPEG EMPEG-CAR MARK I/II DRIVER
-M:      Gary Brubaker <xavyer@ix.netcom.com>
-L:      linux-usb@vger.kernel.org
-S:      Maintained
-F:      drivers/usb/serial/empeg.c
-
-USB SERIAL KEYSPAN DRIVER
-M:      Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-L:      linux-usb@vger.kernel.org
-S:      Maintained
-F:      drivers/usb/serial/*keyspan*
-
-USB SERIAL WHITEHEAT DRIVER
-M:      Support Department <support@connecttech.com>
-L:      linux-usb@vger.kernel.org
-W:      http://www.connecttech.com
-S:      Supported
-F:      drivers/usb/serial/whiteheat*
-
 USB SMSC75XX ETHERNET DRIVER
 M:      Steve Glendinning <steve.glendinning@shawell.net>
 L:      netdev@vger.kernel.org
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index c45f9c0a1b34..b21d553c245b 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -904,6 +904,7 @@ static struct usb_device_id id_table_combined [] = {
         { USB_DEVICE(FTDI_VID, FTDI_LUMEL_PD12_PID) },
         /* Crucible Devices */
         { USB_DEVICE(FTDI_VID, FTDI_CT_COMET_PID) },
+        { USB_DEVICE(FTDI_VID, FTDI_Z3X_PID) },
         { }                                     /* Terminating entry */
 };
 
diff --git a/drivers/usb/serial/ftdi_sio_ids.h b/drivers/usb/serial/ftdi_sio_ids.h
index 1b8af461b522..a7019d1e3058 100644
--- a/drivers/usb/serial/ftdi_sio_ids.h
+++ b/drivers/usb/serial/ftdi_sio_ids.h
@@ -1307,3 +1307,9 @@
  * Manufacturer: Crucible Technologies
  */
 #define FTDI_CT_COMET_PID       0x8e08
+
+/*
+ * Product: Z3X Box
+ * Manufacturer: Smart GSM Team
+ */
+#define FTDI_Z3X_PID            0x0011
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index bedf8e47713b..1e6de4cd079d 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -4,11 +4,6 @@
  * Copyright (C) 2001-2007 Greg Kroah-Hartman (greg@kroah.com)
  * Copyright (C) 2003 IBM Corp.
  *
- * Copyright (C) 2009, 2013 Frank Schäfer <fschaefer.oss@googlemail.com>
- *  - fixes, improvements and documentation for the baud rate encoding methods
- * Copyright (C) 2013 Reinhard Max <max@suse.de>
- *  - fixes and improvements for the divisor based baud rate encoding method
- *
  * Original driver for 2.2.x by anonymous
  *
  *      This program is free software; you can redistribute it and/or
@@ -134,18 +129,10 @@ MODULE_DEVICE_TABLE(usb, id_table);
 
 
 enum pl2303_type {
-        type_0,         /* H version ? */
-        type_1,         /* H version ? */
-        HX_TA,          /* HX(A) / X(A) / TA version  */ /* TODO: improve */
-        HXD_EA_RA_SA,   /* HXD / EA / RA / SA version */ /* TODO: improve */
-        TB,             /* TB version */
-        HX_CLONE,       /* Cheap and less functional clone of the HX chip */
+        type_0,         /* don't know the difference between type 0 and */
+        type_1,         /* type 1, until someone from prolific tells us... */
+        HX,             /* HX version of the pl2303 chip */
 };
-/*
- * NOTE: don't know the difference between type 0 and type 1,
- * until someone from Prolific tells us...
- * TODO: distinguish between X/HX, TA and HXD, EA, RA, SA variants
- */
 
 struct pl2303_serial_private {
         enum pl2303_type type;
@@ -185,7 +172,6 @@ static int pl2303_startup(struct usb_serial *serial)
 {
         struct pl2303_serial_private *spriv;
         enum pl2303_type type = type_0;
-        char *type_str = "unknown (treating as type_0)";
         unsigned char *buf;
 
         spriv = kzalloc(sizeof(*spriv), GFP_KERNEL);
@@ -198,53 +184,15 @@ static int pl2303_startup(struct usb_serial *serial)
                 return -ENOMEM;
         }
 
-        if (serial->dev->descriptor.bDeviceClass == 0x02) {
+        if (serial->dev->descriptor.bDeviceClass == 0x02)
                 type = type_0;
-                type_str = "type_0";
-        } else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40) {
-                /*
-                 * NOTE: The bcdDevice version is the only difference between
-                 * the device descriptors of the X/HX, HXD, EA, RA, SA, TA, TB
-                 */
-                if (le16_to_cpu(serial->dev->descriptor.bcdDevice) == 0x300) {
-                        /* Check if the device is a clone */
-                        pl2303_vendor_read(0x9494, 0, serial, buf);
-                        /*
-                         * NOTE: Not sure if this read is really needed.
-                         * The HX returns 0x00, the clone 0x02, but the Windows
-                         * driver seems to ignore the value and continues.
-                         */
-                        pl2303_vendor_write(0x0606, 0xaa, serial);
-                        pl2303_vendor_read(0x8686, 0, serial, buf);
-                        if (buf[0] != 0xaa) {
-                                type = HX_CLONE;
-                                type_str = "X/HX clone (limited functionality)";
-                        } else {
-                                type = HX_TA;
-                                type_str = "X/HX/TA";
-                        }
-                        pl2303_vendor_write(0x0606, 0x00, serial);
-                } else if (le16_to_cpu(serial->dev->descriptor.bcdDevice)
-                                                                     == 0x400) {
-                        type = HXD_EA_RA_SA;
-                        type_str = "HXD/EA/RA/SA";
-                } else if (le16_to_cpu(serial->dev->descriptor.bcdDevice)
-                                                                     == 0x500) {
-                        type = TB;
-                        type_str = "TB";
-                } else {
-                        dev_info(&serial->interface->dev,
-                                           "unknown/unsupported device type\n");
-                        kfree(spriv);
-                        kfree(buf);
-                        return -ENODEV;
-                }
-        } else if (serial->dev->descriptor.bDeviceClass == 0x00
-                   || serial->dev->descriptor.bDeviceClass == 0xFF) {
+        else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
+                type = HX;
+        else if (serial->dev->descriptor.bDeviceClass == 0x00)
                 type = type_1;
-                type_str = "type_1";
-        }
-        dev_dbg(&serial->interface->dev, "device type: %s\n", type_str);
+        else if (serial->dev->descriptor.bDeviceClass == 0xFF)
+                type = type_1;
+        dev_dbg(&serial->interface->dev, "device type: %d\n", type);
 
         spriv->type = type;
         usb_set_serial_data(serial, spriv);
@@ -259,10 +207,10 @@ static int pl2303_startup(struct usb_serial *serial)
         pl2303_vendor_read(0x8383, 0, serial, buf);
         pl2303_vendor_write(0, 1, serial);
         pl2303_vendor_write(1, 0, serial);
-        if (type == type_0 || type == type_1)
-                pl2303_vendor_write(2, 0x24, serial);
-        else
+        if (type == HX)
                 pl2303_vendor_write(2, 0x44, serial);
+        else
+                pl2303_vendor_write(2, 0x24, serial);
 
         kfree(buf);
         return 0;
@@ -316,174 +264,65 @@ static int pl2303_set_control_lines(struct usb_serial_port *port, u8 value)
         return retval;
 }
 
-static int pl2303_baudrate_encode_direct(int baud, enum pl2303_type type,
-                                                                      u8 buf[4])
+static void pl2303_encode_baudrate(struct tty_struct *tty,
+                                        struct usb_serial_port *port,
+                                        u8 buf[4])
 {
-        /*
-         * NOTE: Only the values defined in baud_sup are supported !
-         * => if unsupported values are set, the PL2303 uses 9600 baud instead
-         * => HX clones just don't work at unsupported baud rates < 115200 baud,
-         *    for baud rates > 115200 they run at 115200 baud
-         */
         const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400, 3600,
-                                 4800, 7200, 9600, 14400, 19200, 28800, 38400,
-                                 57600, 115200, 230400, 460800, 614400, 921600,
-                                 1228800, 2457600, 3000000, 6000000, 12000000 };
+                                 4800, 7200, 9600, 14400, 19200, 28800, 38400,
+                                 57600, 115200, 230400, 460800, 500000, 614400,
+                                 921600, 1228800, 2457600, 3000000, 6000000 };
+
+        struct usb_serial *serial = port->serial;
+        struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
+        int baud;
+        int i;
+
         /*
-         * NOTE: With the exception of type_0/1 devices, the following
-         * additional baud rates are supported (tested with HX rev. 3A only):
-         * 110*, 56000*, 128000, 134400, 161280, 201600, 256000*, 268800,
-         * 403200, 806400.      (*: not HX and HX clones)
-         *
-         * Maximum values: HXD, TB: 12000000; HX, TA: 6000000;
-         *                 type_0+1: 1228800; RA: 921600; HX clones, SA: 115200
-         *
-         * As long as we are not using this encoding method for anything else
-         * than the type_0+1, HX and HX clone chips, there is no point in
-         * complicating the code to support them.
+         * NOTE: Only the values defined in baud_sup are supported!
+         *       => if unsupported values are set, the PL2303 seems to use
+         *          9600 baud (at least my PL2303X always does)
          */
-        int i;
+        baud = tty_get_baud_rate(tty);
+        dev_dbg(&port->dev, "baud requested = %d\n", baud);
+        if (!baud)
+                return;
 
         /* Set baudrate to nearest supported value */
         for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
                 if (baud_sup[i] > baud)
                         break;
         }
+
         if (i == ARRAY_SIZE(baud_sup))
                 baud = baud_sup[i - 1];
         else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
                 baud = baud_sup[i - 1];
         else
                 baud = baud_sup[i];
-        /* Respect the chip type specific baud rate limits */
-        /*
-         * FIXME: as long as we don't know how to distinguish between the
-         * HXD, EA, RA, and SA chip variants, allow the max. value of 12M.
-         */
-        if (type == HX_TA)
-                baud = min_t(int, baud, 6000000);
-        else if (type == type_0 || type == type_1)
-                baud = min_t(int, baud, 1228800);
-        else if (type == HX_CLONE)
-                baud = min_t(int, baud, 115200);
-        /* Direct (standard) baud rate encoding method */
-        put_unaligned_le32(baud, buf);
-
-        return baud;
-}
 
-static int pl2303_baudrate_encode_divisor(int baud, enum pl2303_type type,
-                                                                      u8 buf[4])
-{
-        /*
-         * Divisor based baud rate encoding method
-         *
-         * NOTE: HX clones do NOT support this method.
-         * It's not clear if the type_0/1 chips support it.
-         *
-         * divisor = 12MHz * 32 / baudrate = 2^A * B
-         *
-         * with
-         *
-         * A = buf[1] & 0x0e
-         * B = buf[0]  +  (buf[1] & 0x01) << 8
-         *
-         * Special cases:
-         * => 8 < B < 16: device seems to work not properly
-         * => B <= 8: device uses the max. value B = 512 instead
-         */
-        unsigned int A, B;
+        /* type_0, type_1 only support up to 1228800 baud */
+        if (spriv->type != HX)
+                baud = min_t(int, baud, 1228800);
 
-        /*
-         * NOTE: The Windows driver allows maximum baud rates of 110% of the
-         * specified maximium value.
-         * Quick tests with early (2004) HX (rev. A) chips suggest, that even
-         * higher baud rates (up to the maximum of 24M baud !) are working fine,
-         * but that should really be tested carefully in "real life" scenarios
-         * before removing the upper limit completely.
-         * Baud rates smaller than the specified 75 baud are definitely working
-         * fine.
-         */
-        if (type == type_0 || type == type_1)
-                baud = min_t(int, baud, 1228800 * 1.1);
-        else if (type == HX_TA)
-                baud = min_t(int, baud, 6000000 * 1.1);
-        else if (type == HXD_EA_RA_SA)
-                /* HXD, EA: 12Mbps; RA: 1Mbps; SA: 115200 bps */
-                /*
-                 * FIXME: as long as we don't know how to distinguish between
-                 * these chip variants, allow the max. of these values
-                 */
-                baud = min_t(int, baud, 12000000 * 1.1);
-        else if (type == TB)
-                baud = min_t(int, baud, 12000000 * 1.1);
-        /* Determine factors A and B */
-        A = 0;
-        B = 12000000 * 32 / baud;  /* 12MHz */
-        B <<= 1; /* Add one bit for rounding */
-        while (B > (512 << 1) && A <= 14) {
-                A += 2;
-                B >>= 2;
-        }
-        if (A > 14) { /* max. divisor = min. baudrate reached */
-                A = 14;
-                B = 512;
-                /* => ~45.78 baud */
+        if (baud <= 115200) {
+                put_unaligned_le32(baud, buf);
         } else {
-                B = (B + 1) >> 1; /* Round the last bit */
-        }
-        /* Handle special cases */
-        if (B == 512)
-                B = 0; /* also: 1 to 8 */
-        else if (B < 16)
                 /*
-                 * NOTE: With the current algorithm this happens
-                 * only for A=0 and means that the min. divisor
-                 * (respectively: the max. baudrate) is reached.
+                 * Apparently the formula for higher speeds is:
+                 * baudrate = 12M * 32 / (2^buf[1]) / buf[0]
                  */
-                B = 16;         /* => 24 MBaud */
-        /* Encode the baud rate */
-        buf[3] = 0x80;     /* Select divisor encoding method */
-        buf[2] = 0;
-        buf[1] = (A & 0x0e);            /* A */
-        buf[1] |= ((B & 0x100) >> 8);   /* MSB of B */
-        buf[0] = B & 0xff;              /* 8 LSBs of B */
-        /* Calculate the actual/resulting baud rate */
-        if (B <= 8)
-                B = 512;
-        baud = 12000000 * 32 / ((1 << A) * B);
-
-        return baud;
-}
-
-static void pl2303_encode_baudrate(struct tty_struct *tty,
-                                        struct usb_serial_port *port,
-                                        enum pl2303_type type,
-                                        u8 buf[4])
-{
-        int baud;
+                unsigned tmp = 12000000 * 32 / baud;
+                buf[3] = 0x80;
+                buf[2] = 0;
+                buf[1] = (tmp >= 256);
+                while (tmp >= 256) {
+                        tmp >>= 2;
+                        buf[1] <<= 1;
+                }
+                buf[0] = tmp;
+        }
 
-        baud = tty_get_baud_rate(tty);
-        dev_dbg(&port->dev, "baud requested = %d\n", baud);
-        if (!baud)
-                return;
-        /*
-         * There are two methods for setting/encoding the baud rate
-         * 1) Direct method: encodes the baud rate value directly
-         *    => supported by all chip types
-         * 2) Divisor based method: encodes a divisor to a base value (12MHz*32)
-         *    => not supported by HX clones (and likely type_0/1 chips)
-         *
-         * NOTE: Although the divisor based baud rate encoding method is much
-         * more flexible, some of the standard baud rate values can not be
-         * realized exactly. But the difference is very small (max. 0.2%) and
-         * the device likely uses the same baud rate generator for both methods
-         * so that there is likley no difference.
-         */
-        if (type == type_0 || type == type_1 || type == HX_CLONE)
-                baud = pl2303_baudrate_encode_direct(baud, type, buf);
-        else
-                baud = pl2303_baudrate_encode_divisor(baud, type, buf);
         /* Save resulting baud rate */
         tty_encode_baud_rate(tty, baud, baud);
         dev_dbg(&port->dev, "baud set = %d\n", baud);
@@ -540,8 +379,8 @@ static void pl2303_set_termios(struct tty_struct *tty,
                 dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
         }
 
-        /* For reference:   buf[0]:buf[3] baud rate value */
-        pl2303_encode_baudrate(tty, port, spriv->type, buf);
+        /* For reference buf[0]:buf[3] baud rate value */
+        pl2303_encode_baudrate(tty, port, &buf[0]);
 
         /* For reference buf[4]=0 is 1 stop bits */
         /* For reference buf[4]=1 is 1.5 stop bits */
@@ -618,10 +457,10 @@ static void pl2303_set_termios(struct tty_struct *tty,
         dev_dbg(&port->dev, "0xa1:0x21:0:0  %d - %7ph\n", i, buf);
 
         if (C_CRTSCTS(tty)) {
-                if (spriv->type == type_0 || spriv->type == type_1)
-                        pl2303_vendor_write(0x0, 0x41, serial);
-                else
+                if (spriv->type == HX)
                         pl2303_vendor_write(0x0, 0x61, serial);
+                else
+                        pl2303_vendor_write(0x0, 0x41, serial);
         } else {
                 pl2303_vendor_write(0x0, 0x0, serial);
         }
@@ -658,7 +497,7 @@ static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
         struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
         int result;
 
-        if (spriv->type == type_0 || spriv->type == type_1) {
+        if (spriv->type != HX) {
                 usb_clear_halt(serial->dev, port->write_urb->pipe);
                 usb_clear_halt(serial->dev, port->read_urb->pipe);
         } else {
@@ -833,7 +672,6 @@ static void pl2303_break_ctl(struct tty_struct *tty, int break_state)
         result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
                                  BREAK_REQUEST, BREAK_REQUEST_TYPE, state,
                                  0, NULL, 0, 100);
-        /* NOTE: HX clones don't support sending breaks, -EPIPE is returned */
         if (result)
                 dev_err(&port->dev, "error sending break = %d\n", result);
 }