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Diffstat (limited to 'drivers/usb/serial/pl2303.c')
-rw-r--r--drivers/usb/serial/pl2303.c352
1 files changed, 248 insertions, 104 deletions
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index cb6bbed374f2..e7a84f0f5179 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -4,6 +4,11 @@
* 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
@@ -29,6 +34,7 @@
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
+#include <asm/unaligned.h>
#include "pl2303.h"
/*
@@ -128,10 +134,17 @@ MODULE_DEVICE_TABLE(usb, id_table);
enum pl2303_type {
- 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 */
+ 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 */
};
+/*
+ * 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;
@@ -171,6 +184,7 @@ 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);
@@ -183,15 +197,38 @@ 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;
- else if (serial->dev->descriptor.bMaxPacketSize0 == 0x40)
- type = HX;
- else if (serial->dev->descriptor.bDeviceClass == 0x00)
- type = type_1;
- else if (serial->dev->descriptor.bDeviceClass == 0xFF)
+ 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) {
type = type_1;
- dev_dbg(&serial->interface->dev, "device type: %d\n", type);
+ type_str = "type_1";
+ }
+ dev_dbg(&serial->interface->dev, "device type: %s\n", type_str);
spriv->type = type;
usb_set_serial_data(serial, spriv);
@@ -206,10 +243,10 @@ 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 == HX)
- pl2303_vendor_write(2, 0x44, serial);
- else
+ if (type == type_0 || type == type_1)
pl2303_vendor_write(2, 0x24, serial);
+ else
+ pl2303_vendor_write(2, 0x44, serial);
kfree(buf);
return 0;
@@ -235,6 +272,8 @@ static int pl2303_port_probe(struct usb_serial_port *port)
usb_set_serial_port_data(port, priv);
+ port->port.drain_delay = 256;
+
return 0;
}
@@ -261,6 +300,175 @@ 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])
+{
+ /*
+ * 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 };
+ /*
+ * 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.
+ */
+ int i;
+
+ /* 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;
+
+ /*
+ * 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 */
+ } 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.
+ */
+ 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;
+
+ 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);
+}
+
static void pl2303_set_termios(struct tty_struct *tty,
struct usb_serial_port *port, struct ktermios *old_termios)
{
@@ -268,27 +476,18 @@ static void pl2303_set_termios(struct tty_struct *tty,
struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
struct pl2303_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
- unsigned int cflag;
unsigned char *buf;
- int baud;
int i;
u8 control;
- const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400, 3600,
- 4800, 7200, 9600, 14400, 19200, 28800, 38400,
- 57600, 115200, 230400, 460800, 500000, 614400,
- 921600, 1228800, 2457600, 3000000, 6000000 };
- int baud_floor, baud_ceil;
- int k;
-
- /* The PL2303 is reported to lose bytes if you change
- serial settings even to the same values as before. Thus
- we actually need to filter in this specific case */
+ /*
+ * The PL2303 is reported to lose bytes if you change serial settings
+ * even to the same values as before. Thus we actually need to filter
+ * in this specific case.
+ */
if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
return;
- cflag = tty->termios.c_cflag;
-
buf = kzalloc(7, GFP_KERNEL);
if (!buf) {
dev_err(&port->dev, "%s - out of memory.\n", __func__);
@@ -303,8 +502,8 @@ static void pl2303_set_termios(struct tty_struct *tty,
0, 0, buf, 7, 100);
dev_dbg(&port->dev, "0xa1:0x21:0:0 %d - %7ph\n", i, buf);
- if (cflag & CSIZE) {
- switch (cflag & CSIZE) {
+ if (C_CSIZE(tty)) {
+ switch (C_CSIZE(tty)) {
case CS5:
buf[6] = 5;
break;
@@ -317,73 +516,22 @@ static void pl2303_set_termios(struct tty_struct *tty,
default:
case CS8:
buf[6] = 8;
- break;
}
dev_dbg(&port->dev, "data bits = %d\n", buf[6]);
}
- /* For reference buf[0]:buf[3] baud rate value */
- /* 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)
- */
- baud = tty_get_baud_rate(tty);
- dev_dbg(&port->dev, "baud requested = %d\n", baud);
- if (baud) {
- /* Set baudrate to nearest supported value */
- for (k=0; k<ARRAY_SIZE(baud_sup); k++) {
- if (baud_sup[k] / baud) {
- baud_ceil = baud_sup[k];
- if (k==0) {
- baud = baud_ceil;
- } else {
- baud_floor = baud_sup[k-1];
- if ((baud_ceil % baud)
- > (baud % baud_floor))
- baud = baud_floor;
- else
- baud = baud_ceil;
- }
- break;
- }
- }
- if (baud > 1228800) {
- /* type_0, type_1 only support up to 1228800 baud */
- if (spriv->type != HX)
- baud = 1228800;
- else if (baud > 6000000)
- baud = 6000000;
- }
- dev_dbg(&port->dev, "baud set = %d\n", baud);
- if (baud <= 115200) {
- buf[0] = baud & 0xff;
- buf[1] = (baud >> 8) & 0xff;
- buf[2] = (baud >> 16) & 0xff;
- buf[3] = (baud >> 24) & 0xff;
- } else {
- /* apparently the formula for higher speeds is:
- * baudrate = 12M * 32 / (2^buf[1]) / buf[0]
- */
- unsigned tmp = 12*1000*1000*32 / baud;
- buf[3] = 0x80;
- buf[2] = 0;
- buf[1] = (tmp >= 256);
- while (tmp >= 256) {
- tmp >>= 2;
- buf[1] <<= 1;
- }
- buf[0] = tmp;
- }
- }
+ /* For reference: buf[0]:buf[3] baud rate value */
+ pl2303_encode_baudrate(tty, port, spriv->type, buf);
/* For reference buf[4]=0 is 1 stop bits */
/* For reference buf[4]=1 is 1.5 stop bits */
/* For reference buf[4]=2 is 2 stop bits */
- if (cflag & CSTOPB) {
- /* NOTE: Comply with "real" UARTs / RS232:
+ if (C_CSTOPB(tty)) {
+ /*
+ * NOTE: Comply with "real" UARTs / RS232:
* use 1.5 instead of 2 stop bits with 5 data bits
*/
- if ((cflag & CSIZE) == CS5) {
+ if (C_CSIZE(tty) == CS5) {
buf[4] = 1;
dev_dbg(&port->dev, "stop bits = 1.5\n");
} else {
@@ -395,14 +543,14 @@ static void pl2303_set_termios(struct tty_struct *tty,
dev_dbg(&port->dev, "stop bits = 1\n");
}
- if (cflag & PARENB) {
+ if (C_PARENB(tty)) {
/* For reference buf[5]=0 is none parity */
/* For reference buf[5]=1 is odd parity */
/* For reference buf[5]=2 is even parity */
/* For reference buf[5]=3 is mark parity */
/* For reference buf[5]=4 is space parity */
- if (cflag & PARODD) {
- if (cflag & CMSPAR) {
+ if (C_PARODD(tty)) {
+ if (tty->termios.c_cflag & CMSPAR) {
buf[5] = 3;
dev_dbg(&port->dev, "parity = mark\n");
} else {
@@ -410,7 +558,7 @@ static void pl2303_set_termios(struct tty_struct *tty,
dev_dbg(&port->dev, "parity = odd\n");
}
} else {
- if (cflag & CMSPAR) {
+ if (tty->termios.c_cflag & CMSPAR) {
buf[5] = 4;
dev_dbg(&port->dev, "parity = space\n");
} else {
@@ -431,7 +579,7 @@ static void pl2303_set_termios(struct tty_struct *tty,
/* change control lines if we are switching to or from B0 */
spin_lock_irqsave(&priv->lock, flags);
control = priv->line_control;
- if ((cflag & CBAUD) == B0)
+ if (C_BAUD(tty) == B0)
priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
@@ -443,26 +591,21 @@ static void pl2303_set_termios(struct tty_struct *tty,
spin_unlock_irqrestore(&priv->lock, flags);
}
- buf[0] = buf[1] = buf[2] = buf[3] = buf[4] = buf[5] = buf[6] = 0;
-
+ memset(buf, 0, 7);
i = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
0, 0, buf, 7, 100);
dev_dbg(&port->dev, "0xa1:0x21:0:0 %d - %7ph\n", i, buf);
- if (cflag & CRTSCTS) {
- if (spriv->type == HX)
- pl2303_vendor_write(0x0, 0x61, serial);
- else
+ if (C_CRTSCTS(tty)) {
+ if (spriv->type == type_0 || spriv->type == type_1)
pl2303_vendor_write(0x0, 0x41, serial);
+ else
+ pl2303_vendor_write(0x0, 0x61, serial);
} else {
pl2303_vendor_write(0x0, 0x0, serial);
}
- /* Save resulting baud rate */
- if (baud)
- tty_encode_baud_rate(tty, baud, baud);
-
kfree(buf);
}
@@ -495,7 +638,7 @@ 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 != HX) {
+ if (spriv->type == type_0 || spriv->type == type_1) {
usb_clear_halt(serial->dev, port->write_urb->pipe);
usb_clear_halt(serial->dev, port->read_urb->pipe);
} else {
@@ -521,7 +664,6 @@ static int pl2303_open(struct tty_struct *tty, struct usb_serial_port *port)
return result;
}
- port->port.drain_delay = 256;
return 0;
}
@@ -789,8 +931,10 @@ static void pl2303_process_read_urb(struct urb *urb)
tty_flag = TTY_PARITY;
else if (line_status & UART_FRAME_ERROR)
tty_flag = TTY_FRAME;
- dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__, tty_flag);
+ if (tty_flag != TTY_NORMAL)
+ dev_dbg(&port->dev, "%s - tty_flag = %d\n", __func__,
+ tty_flag);
/* overrun is special, not associated with a char */
if (line_status & UART_OVERRUN_ERROR)
tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.