diff options
Diffstat (limited to 'drivers/usb/serial/pl2303.c')
-rw-r--r-- | drivers/usb/serial/pl2303.c | 253 |
1 files changed, 56 insertions, 197 deletions
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c index e7a84f0f5179..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 @@ -134,17 +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 */ + 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; @@ -184,7 +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); @@ -197,38 +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) { - type = HX_TA; - type_str = "X/HX/TA"; - } 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); @@ -243,10 +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; @@ -300,170 +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 seems to - * use 9600 baud (at least my PL2303X always does) - */ 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) - * - * Maximum values: HXD, TB: 12000000; HX, TA: 6000000; - * type_0+1: 1228800; RA: 921600; SA: 115200 - * - * As long as we are not using this encoding method for anything else - * than the type_0+1 and HX 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); - /* 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: it's not clear if the type_0/1 chips support this method - * - * 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) - * => supported by HX chips (and likely not by 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) - 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); @@ -520,8 +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 */ @@ -598,10 +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); } @@ -638,7 +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 { |