linux/drivers/tty/serdev/serdev-ttyport.c
Linus Torvalds db5933225f TTY/Staging driver updates for 4.16-rc1
Here is the big tty/serial driver update for 4.16-rc1.
 
 The usual number of various serial driver fixes and updates to try to
 get them to work with crazy hardware configurations (seriously, how many
 different ways are hardware engineers going to come up with to hook up a
 simple UART?)
 
 There is also some serdev bugfixes and updates, as well as a smattering
 of other small fixes in here.
 
 All have been in the linux-next tree for a while, with no reported
 issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/staging driver updates from Greg KH:
 "Here is the big tty/serial driver update for 4.16-rc1.

  The usual number of various serial driver fixes and updates to try to
  get them to work with crazy hardware configurations (seriously, how
  many different ways are hardware engineers going to come up with to
  hook up a simple UART?)

  There is also some serdev bugfixes and updates, as well as a
  smattering of other small fixes in here.

  All have been in the linux-next tree for a while, with no reported
  issues"

* tag 'tty-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (65 commits)
  tty: serial: exar: Relocate sleep wake-up handling
  tty: fix data race between tty_init_dev and flush of buf
  serial: imx: fix endless loop during suspend
  serial: core: mark port as initialized after successful IRQ change
  serdev: only match serdev devices
  serdev: do not generate modaliases for controllers
  serial: mxs-auart: don't use GPIOF_* with gpiod_get_direction
  serial: 8250_dw: Revert "Improve clock rate setting"
  MAINTAINERS: Add myself as designated reviewer for 8250_dw
  gpio: serial: max310x: Support open-drain configuration for GPIOs
  serdev: Fix serdev_uevent failure on ACPI enumerated serdev-controllers
  serial: 8250_ingenic: Parse earlycon options
  serial: 8250_ingenic: Add support for the JZ4770 SoC
  serial: core: Make uart_parse_options take const char* argument
  serial: 8250_of: fix return code when probe function fails to get reset
  serial: imx: Only wakeup via RTSDEN bit if the system has RTS/CTS
  serial: 8250_uniphier: fix error return code in uniphier_uart_probe()
  tty: n_gsm: Allow ADM response in addition to UA for control dlci
  tty: omap-serial: Fix initial on-boot RTS GPIO level
  tty: serial: jsm: Add one check against NULL pointer dereference
  ...
2018-02-01 09:46:00 -08:00

321 lines
7.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
*/
#include <linux/kernel.h>
#include <linux/serdev.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/poll.h>
#define SERPORT_ACTIVE 1
struct serport {
struct tty_port *port;
struct tty_struct *tty;
struct tty_driver *tty_drv;
int tty_idx;
unsigned long flags;
};
/*
* Callback functions from the tty port.
*/
static int ttyport_receive_buf(struct tty_port *port, const unsigned char *cp,
const unsigned char *fp, size_t count)
{
struct serdev_controller *ctrl = port->client_data;
struct serport *serport = serdev_controller_get_drvdata(ctrl);
int ret;
if (!test_bit(SERPORT_ACTIVE, &serport->flags))
return 0;
ret = serdev_controller_receive_buf(ctrl, cp, count);
dev_WARN_ONCE(&ctrl->dev, ret < 0 || ret > count,
"receive_buf returns %d (count = %zu)\n",
ret, count);
if (ret < 0)
return 0;
else if (ret > count)
return count;
return ret;
}
static void ttyport_write_wakeup(struct tty_port *port)
{
struct serdev_controller *ctrl = port->client_data;
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty;
tty = tty_port_tty_get(port);
if (!tty)
return;
if (test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags) &&
test_bit(SERPORT_ACTIVE, &serport->flags))
serdev_controller_write_wakeup(ctrl);
/* Wake up any tty_wait_until_sent() */
wake_up_interruptible(&tty->write_wait);
tty_kref_put(tty);
}
static const struct tty_port_client_operations client_ops = {
.receive_buf = ttyport_receive_buf,
.write_wakeup = ttyport_write_wakeup,
};
/*
* Callback functions from the serdev core.
*/
static int ttyport_write_buf(struct serdev_controller *ctrl, const unsigned char *data, size_t len)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
if (!test_bit(SERPORT_ACTIVE, &serport->flags))
return 0;
set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
return tty->ops->write(serport->tty, data, len);
}
static void ttyport_write_flush(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
tty_driver_flush_buffer(tty);
}
static int ttyport_write_room(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
return tty_write_room(tty);
}
static int ttyport_open(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty;
struct ktermios ktermios;
int ret;
tty = tty_init_dev(serport->tty_drv, serport->tty_idx);
if (IS_ERR(tty))
return PTR_ERR(tty);
serport->tty = tty;
if (!tty->ops->open || !tty->ops->close) {
ret = -ENODEV;
goto err_unlock;
}
ret = tty->ops->open(serport->tty, NULL);
if (ret)
goto err_close;
tty_unlock(serport->tty);
/* Bring the UART into a known 8 bits no parity hw fc state */
ktermios = tty->termios;
ktermios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP |
INLCR | IGNCR | ICRNL | IXON);
ktermios.c_oflag &= ~OPOST;
ktermios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
ktermios.c_cflag &= ~(CSIZE | PARENB);
ktermios.c_cflag |= CS8;
ktermios.c_cflag |= CRTSCTS;
/* Hangups are not supported so make sure to ignore carrier detect. */
ktermios.c_cflag |= CLOCAL;
tty_set_termios(tty, &ktermios);
set_bit(SERPORT_ACTIVE, &serport->flags);
return 0;
err_close:
tty->ops->close(tty, NULL);
err_unlock:
tty_unlock(tty);
tty_release_struct(tty, serport->tty_idx);
return ret;
}
static void ttyport_close(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
clear_bit(SERPORT_ACTIVE, &serport->flags);
tty_lock(tty);
if (tty->ops->close)
tty->ops->close(tty, NULL);
tty_unlock(tty);
tty_release_struct(tty, serport->tty_idx);
}
static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigned int speed)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
struct ktermios ktermios = tty->termios;
ktermios.c_cflag &= ~CBAUD;
tty_termios_encode_baud_rate(&ktermios, speed, speed);
/* tty_set_termios() return not checked as it is always 0 */
tty_set_termios(tty, &ktermios);
return ktermios.c_ospeed;
}
static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
struct ktermios ktermios = tty->termios;
if (enable)
ktermios.c_cflag |= CRTSCTS;
else
ktermios.c_cflag &= ~CRTSCTS;
tty_set_termios(tty, &ktermios);
}
static int ttyport_set_parity(struct serdev_controller *ctrl,
enum serdev_parity parity)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
struct ktermios ktermios = tty->termios;
ktermios.c_cflag &= ~(PARENB | PARODD | CMSPAR);
if (parity != SERDEV_PARITY_NONE) {
ktermios.c_cflag |= PARENB;
if (parity == SERDEV_PARITY_ODD)
ktermios.c_cflag |= PARODD;
}
tty_set_termios(tty, &ktermios);
if ((tty->termios.c_cflag & (PARENB | PARODD | CMSPAR)) !=
(ktermios.c_cflag & (PARENB | PARODD | CMSPAR)))
return -EINVAL;
return 0;
}
static void ttyport_wait_until_sent(struct serdev_controller *ctrl, long timeout)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
tty_wait_until_sent(tty, timeout);
}
static int ttyport_get_tiocm(struct serdev_controller *ctrl)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
if (!tty->ops->tiocmget)
return -ENOTSUPP;
return tty->driver->ops->tiocmget(tty);
}
static int ttyport_set_tiocm(struct serdev_controller *ctrl, unsigned int set, unsigned int clear)
{
struct serport *serport = serdev_controller_get_drvdata(ctrl);
struct tty_struct *tty = serport->tty;
if (!tty->ops->tiocmset)
return -ENOTSUPP;
return tty->driver->ops->tiocmset(tty, set, clear);
}
static const struct serdev_controller_ops ctrl_ops = {
.write_buf = ttyport_write_buf,
.write_flush = ttyport_write_flush,
.write_room = ttyport_write_room,
.open = ttyport_open,
.close = ttyport_close,
.set_flow_control = ttyport_set_flow_control,
.set_parity = ttyport_set_parity,
.set_baudrate = ttyport_set_baudrate,
.wait_until_sent = ttyport_wait_until_sent,
.get_tiocm = ttyport_get_tiocm,
.set_tiocm = ttyport_set_tiocm,
};
struct device *serdev_tty_port_register(struct tty_port *port,
struct device *parent,
struct tty_driver *drv, int idx)
{
const struct tty_port_client_operations *old_ops;
struct serdev_controller *ctrl;
struct serport *serport;
int ret;
if (!port || !drv || !parent)
return ERR_PTR(-ENODEV);
ctrl = serdev_controller_alloc(parent, sizeof(struct serport));
if (!ctrl)
return ERR_PTR(-ENOMEM);
serport = serdev_controller_get_drvdata(ctrl);
serport->port = port;
serport->tty_idx = idx;
serport->tty_drv = drv;
ctrl->ops = &ctrl_ops;
old_ops = port->client_ops;
port->client_ops = &client_ops;
port->client_data = ctrl;
ret = serdev_controller_add(ctrl);
if (ret)
goto err_reset_data;
dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx);
return &ctrl->dev;
err_reset_data:
port->client_data = NULL;
port->client_ops = old_ops;
serdev_controller_put(ctrl);
return ERR_PTR(ret);
}
int serdev_tty_port_unregister(struct tty_port *port)
{
struct serdev_controller *ctrl = port->client_data;
struct serport *serport = serdev_controller_get_drvdata(ctrl);
if (!serport)
return -ENODEV;
serdev_controller_remove(ctrl);
port->client_ops = NULL;
port->client_data = NULL;
serdev_controller_put(ctrl);
return 0;
}