From fff0a2ca3a061c230b0e905e7586267a517538ac Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Wed, 12 Apr 2017 18:37:15 -0400 Subject: [PATCH] tty: move baudrate handling code to a file of its own To allow reuse without the rest of the tty_ioctl code. No logical changes from this patch. Signed-off-by: Nicolas Pitre Signed-off-by: Greg Kroah-Hartman --- drivers/tty/Makefile | 3 +- drivers/tty/tty_baudrate.c | 232 +++++++++++++++++++++++++++++++++++++ drivers/tty/tty_ioctl.c | 222 ----------------------------------- 3 files changed, 234 insertions(+), 223 deletions(-) create mode 100644 drivers/tty/tty_baudrate.c diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile index b95bed92da9f..6983b5a49ec3 100644 --- a/drivers/tty/Makefile +++ b/drivers/tty/Makefile @@ -1,5 +1,6 @@ obj-$(CONFIG_TTY) += tty_io.o n_tty.o tty_ioctl.o tty_ldisc.o \ - tty_buffer.o tty_port.o tty_mutex.o tty_ldsem.o + tty_buffer.o tty_port.o tty_mutex.o \ + tty_ldsem.o tty_baudrate.o obj-$(CONFIG_LEGACY_PTYS) += pty.o obj-$(CONFIG_UNIX98_PTYS) += pty.o obj-$(CONFIG_AUDIT) += tty_audit.o diff --git a/drivers/tty/tty_baudrate.c b/drivers/tty/tty_baudrate.c new file mode 100644 index 000000000000..5c33fd25676d --- /dev/null +++ b/drivers/tty/tty_baudrate.c @@ -0,0 +1,232 @@ +/* + * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds + */ + +#include +#include +#include +#include +#include + + +/* + * Routine which returns the baud rate of the tty + * + * Note that the baud_table needs to be kept in sync with the + * include/asm/termbits.h file. + */ +static const speed_t baud_table[] = { + 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, + 9600, 19200, 38400, 57600, 115200, 230400, 460800, +#ifdef __sparc__ + 76800, 153600, 307200, 614400, 921600 +#else + 500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000, + 2500000, 3000000, 3500000, 4000000 +#endif +}; + +#ifndef __sparc__ +static const tcflag_t baud_bits[] = { + B0, B50, B75, B110, B134, B150, B200, B300, B600, + B1200, B1800, B2400, B4800, B9600, B19200, B38400, + B57600, B115200, B230400, B460800, B500000, B576000, + B921600, B1000000, B1152000, B1500000, B2000000, B2500000, + B3000000, B3500000, B4000000 +}; +#else +static const tcflag_t baud_bits[] = { + B0, B50, B75, B110, B134, B150, B200, B300, B600, + B1200, B1800, B2400, B4800, B9600, B19200, B38400, + B57600, B115200, B230400, B460800, B76800, B153600, + B307200, B614400, B921600 +}; +#endif + +static int n_baud_table = ARRAY_SIZE(baud_table); + +/** + * tty_termios_baud_rate + * @termios: termios structure + * + * Convert termios baud rate data into a speed. This should be called + * with the termios lock held if this termios is a terminal termios + * structure. May change the termios data. Device drivers can call this + * function but should use ->c_[io]speed directly as they are updated. + * + * Locking: none + */ + +speed_t tty_termios_baud_rate(struct ktermios *termios) +{ + unsigned int cbaud; + + cbaud = termios->c_cflag & CBAUD; + +#ifdef BOTHER + /* Magic token for arbitrary speed via c_ispeed/c_ospeed */ + if (cbaud == BOTHER) + return termios->c_ospeed; +#endif + if (cbaud & CBAUDEX) { + cbaud &= ~CBAUDEX; + + if (cbaud < 1 || cbaud + 15 > n_baud_table) + termios->c_cflag &= ~CBAUDEX; + else + cbaud += 15; + } + return baud_table[cbaud]; +} +EXPORT_SYMBOL(tty_termios_baud_rate); + +/** + * tty_termios_input_baud_rate + * @termios: termios structure + * + * Convert termios baud rate data into a speed. This should be called + * with the termios lock held if this termios is a terminal termios + * structure. May change the termios data. Device drivers can call this + * function but should use ->c_[io]speed directly as they are updated. + * + * Locking: none + */ + +speed_t tty_termios_input_baud_rate(struct ktermios *termios) +{ +#ifdef IBSHIFT + unsigned int cbaud = (termios->c_cflag >> IBSHIFT) & CBAUD; + + if (cbaud == B0) + return tty_termios_baud_rate(termios); + + /* Magic token for arbitrary speed via c_ispeed*/ + if (cbaud == BOTHER) + return termios->c_ispeed; + + if (cbaud & CBAUDEX) { + cbaud &= ~CBAUDEX; + + if (cbaud < 1 || cbaud + 15 > n_baud_table) + termios->c_cflag &= ~(CBAUDEX << IBSHIFT); + else + cbaud += 15; + } + return baud_table[cbaud]; +#else + return tty_termios_baud_rate(termios); +#endif +} +EXPORT_SYMBOL(tty_termios_input_baud_rate); + +/** + * tty_termios_encode_baud_rate + * @termios: ktermios structure holding user requested state + * @ispeed: input speed + * @ospeed: output speed + * + * Encode the speeds set into the passed termios structure. This is + * used as a library helper for drivers so that they can report back + * the actual speed selected when it differs from the speed requested + * + * For maximal back compatibility with legacy SYS5/POSIX *nix behaviour + * we need to carefully set the bits when the user does not get the + * desired speed. We allow small margins and preserve as much of possible + * of the input intent to keep compatibility. + * + * Locking: Caller should hold termios lock. This is already held + * when calling this function from the driver termios handler. + * + * The ifdefs deal with platforms whose owners have yet to update them + * and will all go away once this is done. + */ + +void tty_termios_encode_baud_rate(struct ktermios *termios, + speed_t ibaud, speed_t obaud) +{ + int i = 0; + int ifound = -1, ofound = -1; + int iclose = ibaud/50, oclose = obaud/50; + int ibinput = 0; + + if (obaud == 0) /* CD dropped */ + ibaud = 0; /* Clear ibaud to be sure */ + + termios->c_ispeed = ibaud; + termios->c_ospeed = obaud; + +#ifdef BOTHER + /* If the user asked for a precise weird speed give a precise weird + answer. If they asked for a Bfoo speed they may have problems + digesting non-exact replies so fuzz a bit */ + + if ((termios->c_cflag & CBAUD) == BOTHER) + oclose = 0; + if (((termios->c_cflag >> IBSHIFT) & CBAUD) == BOTHER) + iclose = 0; + if ((termios->c_cflag >> IBSHIFT) & CBAUD) + ibinput = 1; /* An input speed was specified */ +#endif + termios->c_cflag &= ~CBAUD; + + /* + * Our goal is to find a close match to the standard baud rate + * returned. Walk the baud rate table and if we get a very close + * match then report back the speed as a POSIX Bxxxx value by + * preference + */ + + do { + if (obaud - oclose <= baud_table[i] && + obaud + oclose >= baud_table[i]) { + termios->c_cflag |= baud_bits[i]; + ofound = i; + } + if (ibaud - iclose <= baud_table[i] && + ibaud + iclose >= baud_table[i]) { + /* For the case input == output don't set IBAUD bits + if the user didn't do so */ + if (ofound == i && !ibinput) + ifound = i; +#ifdef IBSHIFT + else { + ifound = i; + termios->c_cflag |= (baud_bits[i] << IBSHIFT); + } +#endif + } + } while (++i < n_baud_table); + + /* + * If we found no match then use BOTHER if provided or warn + * the user their platform maintainer needs to wake up if not. + */ +#ifdef BOTHER + if (ofound == -1) + termios->c_cflag |= BOTHER; + /* Set exact input bits only if the input and output differ or the + user already did */ + if (ifound == -1 && (ibaud != obaud || ibinput)) + termios->c_cflag |= (BOTHER << IBSHIFT); +#else + if (ifound == -1 || ofound == -1) + pr_warn_once("tty: Unable to return correct speed data as your architecture needs updating.\n"); +#endif +} +EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate); + +/** + * tty_encode_baud_rate - set baud rate of the tty + * @ibaud: input baud rate + * @obad: output baud rate + * + * Update the current termios data for the tty with the new speed + * settings. The caller must hold the termios_rwsem for the tty in + * question. + */ + +void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud) +{ + tty_termios_encode_baud_rate(&tty->termios, ibaud, obaud); +} +EXPORT_SYMBOL_GPL(tty_encode_baud_rate); diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c index a9a978731c5b..efa96e6c4c1b 100644 --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -258,228 +258,6 @@ static void unset_locked_termios(struct tty_struct *tty, struct ktermios *old) /* FIXME: What should we do for i/ospeed */ } -/* - * Routine which returns the baud rate of the tty - * - * Note that the baud_table needs to be kept in sync with the - * include/asm/termbits.h file. - */ -static const speed_t baud_table[] = { - 0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, - 9600, 19200, 38400, 57600, 115200, 230400, 460800, -#ifdef __sparc__ - 76800, 153600, 307200, 614400, 921600 -#else - 500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000, - 2500000, 3000000, 3500000, 4000000 -#endif -}; - -#ifndef __sparc__ -static const tcflag_t baud_bits[] = { - B0, B50, B75, B110, B134, B150, B200, B300, B600, - B1200, B1800, B2400, B4800, B9600, B19200, B38400, - B57600, B115200, B230400, B460800, B500000, B576000, - B921600, B1000000, B1152000, B1500000, B2000000, B2500000, - B3000000, B3500000, B4000000 -}; -#else -static const tcflag_t baud_bits[] = { - B0, B50, B75, B110, B134, B150, B200, B300, B600, - B1200, B1800, B2400, B4800, B9600, B19200, B38400, - B57600, B115200, B230400, B460800, B76800, B153600, - B307200, B614400, B921600 -}; -#endif - -static int n_baud_table = ARRAY_SIZE(baud_table); - -/** - * tty_termios_baud_rate - * @termios: termios structure - * - * Convert termios baud rate data into a speed. This should be called - * with the termios lock held if this termios is a terminal termios - * structure. May change the termios data. Device drivers can call this - * function but should use ->c_[io]speed directly as they are updated. - * - * Locking: none - */ - -speed_t tty_termios_baud_rate(struct ktermios *termios) -{ - unsigned int cbaud; - - cbaud = termios->c_cflag & CBAUD; - -#ifdef BOTHER - /* Magic token for arbitrary speed via c_ispeed/c_ospeed */ - if (cbaud == BOTHER) - return termios->c_ospeed; -#endif - if (cbaud & CBAUDEX) { - cbaud &= ~CBAUDEX; - - if (cbaud < 1 || cbaud + 15 > n_baud_table) - termios->c_cflag &= ~CBAUDEX; - else - cbaud += 15; - } - return baud_table[cbaud]; -} -EXPORT_SYMBOL(tty_termios_baud_rate); - -/** - * tty_termios_input_baud_rate - * @termios: termios structure - * - * Convert termios baud rate data into a speed. This should be called - * with the termios lock held if this termios is a terminal termios - * structure. May change the termios data. Device drivers can call this - * function but should use ->c_[io]speed directly as they are updated. - * - * Locking: none - */ - -speed_t tty_termios_input_baud_rate(struct ktermios *termios) -{ -#ifdef IBSHIFT - unsigned int cbaud = (termios->c_cflag >> IBSHIFT) & CBAUD; - - if (cbaud == B0) - return tty_termios_baud_rate(termios); - - /* Magic token for arbitrary speed via c_ispeed*/ - if (cbaud == BOTHER) - return termios->c_ispeed; - - if (cbaud & CBAUDEX) { - cbaud &= ~CBAUDEX; - - if (cbaud < 1 || cbaud + 15 > n_baud_table) - termios->c_cflag &= ~(CBAUDEX << IBSHIFT); - else - cbaud += 15; - } - return baud_table[cbaud]; -#else - return tty_termios_baud_rate(termios); -#endif -} -EXPORT_SYMBOL(tty_termios_input_baud_rate); - -/** - * tty_termios_encode_baud_rate - * @termios: ktermios structure holding user requested state - * @ispeed: input speed - * @ospeed: output speed - * - * Encode the speeds set into the passed termios structure. This is - * used as a library helper for drivers so that they can report back - * the actual speed selected when it differs from the speed requested - * - * For maximal back compatibility with legacy SYS5/POSIX *nix behaviour - * we need to carefully set the bits when the user does not get the - * desired speed. We allow small margins and preserve as much of possible - * of the input intent to keep compatibility. - * - * Locking: Caller should hold termios lock. This is already held - * when calling this function from the driver termios handler. - * - * The ifdefs deal with platforms whose owners have yet to update them - * and will all go away once this is done. - */ - -void tty_termios_encode_baud_rate(struct ktermios *termios, - speed_t ibaud, speed_t obaud) -{ - int i = 0; - int ifound = -1, ofound = -1; - int iclose = ibaud/50, oclose = obaud/50; - int ibinput = 0; - - if (obaud == 0) /* CD dropped */ - ibaud = 0; /* Clear ibaud to be sure */ - - termios->c_ispeed = ibaud; - termios->c_ospeed = obaud; - -#ifdef BOTHER - /* If the user asked for a precise weird speed give a precise weird - answer. If they asked for a Bfoo speed they may have problems - digesting non-exact replies so fuzz a bit */ - - if ((termios->c_cflag & CBAUD) == BOTHER) - oclose = 0; - if (((termios->c_cflag >> IBSHIFT) & CBAUD) == BOTHER) - iclose = 0; - if ((termios->c_cflag >> IBSHIFT) & CBAUD) - ibinput = 1; /* An input speed was specified */ -#endif - termios->c_cflag &= ~CBAUD; - - /* - * Our goal is to find a close match to the standard baud rate - * returned. Walk the baud rate table and if we get a very close - * match then report back the speed as a POSIX Bxxxx value by - * preference - */ - - do { - if (obaud - oclose <= baud_table[i] && - obaud + oclose >= baud_table[i]) { - termios->c_cflag |= baud_bits[i]; - ofound = i; - } - if (ibaud - iclose <= baud_table[i] && - ibaud + iclose >= baud_table[i]) { - /* For the case input == output don't set IBAUD bits - if the user didn't do so */ - if (ofound == i && !ibinput) - ifound = i; -#ifdef IBSHIFT - else { - ifound = i; - termios->c_cflag |= (baud_bits[i] << IBSHIFT); - } -#endif - } - } while (++i < n_baud_table); - - /* - * If we found no match then use BOTHER if provided or warn - * the user their platform maintainer needs to wake up if not. - */ -#ifdef BOTHER - if (ofound == -1) - termios->c_cflag |= BOTHER; - /* Set exact input bits only if the input and output differ or the - user already did */ - if (ifound == -1 && (ibaud != obaud || ibinput)) - termios->c_cflag |= (BOTHER << IBSHIFT); -#else - if (ifound == -1 || ofound == -1) - pr_warn_once("tty: Unable to return correct speed data as your architecture needs updating.\n"); -#endif -} -EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate); - -/** - * tty_encode_baud_rate - set baud rate of the tty - * @ibaud: input baud rate - * @obad: output baud rate - * - * Update the current termios data for the tty with the new speed - * settings. The caller must hold the termios_rwsem for the tty in - * question. - */ - -void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud) -{ - tty_termios_encode_baud_rate(&tty->termios, ibaud, obaud); -} -EXPORT_SYMBOL_GPL(tty_encode_baud_rate); - /** * tty_termios_copy_hw - copy hardware settings * @new: New termios