linux/drivers/usb/serial/upd78f0730.c
Johan Hovold 6ff58ae17f USB: serial: return errors from break handling
Start propagating errors to user space when setting the break state
fails.

This will be used by follow-on changes to also report when a driver or
device does not support break control.

Tested-by: Corey Minyard <cminyard@mvista.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
2023-06-07 17:00:23 +02:00

436 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Renesas Electronics uPD78F0730 USB to serial converter driver
*
* Copyright (C) 2014,2016 Maksim Salau <maksim.salau@gmail.com>
*
* Protocol of the adaptor is described in the application note U19660EJ1V0AN00
* μPD78F0730 8-bit Single-Chip Microcontroller
* USB-to-Serial Conversion Software
* <https://www.renesas.com/en-eu/doc/DocumentServer/026/U19660EJ1V0AN00.pdf>
*
* The adaptor functionality is limited to the following:
* - data bits: 7 or 8
* - stop bits: 1 or 2
* - parity: even, odd or none
* - flow control: none
* - baud rates: 0, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 153600
* - signals: DTR, RTS and BREAK
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#define DRIVER_DESC "Renesas uPD78F0730 USB to serial converter driver"
#define DRIVER_AUTHOR "Maksim Salau <maksim.salau@gmail.com>"
static const struct usb_device_id id_table[] = {
{ USB_DEVICE(0x0409, 0x0063) }, /* V850ESJX3-STICK */
{ USB_DEVICE(0x045B, 0x0212) }, /* YRPBRL78G13, YRPBRL78G14 */
{ USB_DEVICE(0x064B, 0x7825) }, /* Analog Devices EVAL-ADXL362Z-DB */
{}
};
MODULE_DEVICE_TABLE(usb, id_table);
/*
* Each adaptor is associated with a private structure, that holds the current
* state of control signals (DTR, RTS and BREAK).
*/
struct upd78f0730_port_private {
struct mutex lock; /* mutex to protect line_signals */
u8 line_signals;
};
/* Op-codes of control commands */
#define UPD78F0730_CMD_LINE_CONTROL 0x00
#define UPD78F0730_CMD_SET_DTR_RTS 0x01
#define UPD78F0730_CMD_SET_XON_XOFF_CHR 0x02
#define UPD78F0730_CMD_OPEN_CLOSE 0x03
#define UPD78F0730_CMD_SET_ERR_CHR 0x04
/* Data sizes in UPD78F0730_CMD_LINE_CONTROL command */
#define UPD78F0730_DATA_SIZE_7_BITS 0x00
#define UPD78F0730_DATA_SIZE_8_BITS 0x01
#define UPD78F0730_DATA_SIZE_MASK 0x01
/* Stop-bit modes in UPD78F0730_CMD_LINE_CONTROL command */
#define UPD78F0730_STOP_BIT_1_BIT 0x00
#define UPD78F0730_STOP_BIT_2_BIT 0x02
#define UPD78F0730_STOP_BIT_MASK 0x02
/* Parity modes in UPD78F0730_CMD_LINE_CONTROL command */
#define UPD78F0730_PARITY_NONE 0x00
#define UPD78F0730_PARITY_EVEN 0x04
#define UPD78F0730_PARITY_ODD 0x08
#define UPD78F0730_PARITY_MASK 0x0C
/* Flow control modes in UPD78F0730_CMD_LINE_CONTROL command */
#define UPD78F0730_FLOW_CONTROL_NONE 0x00
#define UPD78F0730_FLOW_CONTROL_HW 0x10
#define UPD78F0730_FLOW_CONTROL_SW 0x20
#define UPD78F0730_FLOW_CONTROL_MASK 0x30
/* Control signal bits in UPD78F0730_CMD_SET_DTR_RTS command */
#define UPD78F0730_RTS 0x01
#define UPD78F0730_DTR 0x02
#define UPD78F0730_BREAK 0x04
/* Port modes in UPD78F0730_CMD_OPEN_CLOSE command */
#define UPD78F0730_PORT_CLOSE 0x00
#define UPD78F0730_PORT_OPEN 0x01
/* Error character substitution modes in UPD78F0730_CMD_SET_ERR_CHR command */
#define UPD78F0730_ERR_CHR_DISABLED 0x00
#define UPD78F0730_ERR_CHR_ENABLED 0x01
/*
* Declaration of command structures
*/
/* UPD78F0730_CMD_LINE_CONTROL command */
struct upd78f0730_line_control {
u8 opcode;
__le32 baud_rate;
u8 params;
} __packed;
/* UPD78F0730_CMD_SET_DTR_RTS command */
struct upd78f0730_set_dtr_rts {
u8 opcode;
u8 params;
};
/* UPD78F0730_CMD_SET_XON_OFF_CHR command */
struct upd78f0730_set_xon_xoff_chr {
u8 opcode;
u8 xon;
u8 xoff;
};
/* UPD78F0730_CMD_OPEN_CLOSE command */
struct upd78f0730_open_close {
u8 opcode;
u8 state;
};
/* UPD78F0730_CMD_SET_ERR_CHR command */
struct upd78f0730_set_err_chr {
u8 opcode;
u8 state;
u8 err_char;
};
static int upd78f0730_send_ctl(struct usb_serial_port *port,
const void *data, int size)
{
struct usb_device *usbdev = port->serial->dev;
void *buf;
int res;
if (size <= 0 || !data)
return -EINVAL;
buf = kmemdup(data, size, GFP_KERNEL);
if (!buf)
return -ENOMEM;
res = usb_control_msg(usbdev, usb_sndctrlpipe(usbdev, 0), 0x00,
USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT,
0x0000, 0x0000, buf, size, USB_CTRL_SET_TIMEOUT);
kfree(buf);
if (res < 0) {
struct device *dev = &port->dev;
dev_err(dev, "failed to send control request %02x: %d\n",
*(u8 *)data, res);
return res;
}
return 0;
}
static int upd78f0730_port_probe(struct usb_serial_port *port)
{
struct upd78f0730_port_private *private;
private = kzalloc(sizeof(*private), GFP_KERNEL);
if (!private)
return -ENOMEM;
mutex_init(&private->lock);
usb_set_serial_port_data(port, private);
return 0;
}
static void upd78f0730_port_remove(struct usb_serial_port *port)
{
struct upd78f0730_port_private *private;
private = usb_get_serial_port_data(port);
mutex_destroy(&private->lock);
kfree(private);
}
static int upd78f0730_tiocmget(struct tty_struct *tty)
{
struct upd78f0730_port_private *private;
struct usb_serial_port *port = tty->driver_data;
int signals;
int res;
private = usb_get_serial_port_data(port);
mutex_lock(&private->lock);
signals = private->line_signals;
mutex_unlock(&private->lock);
res = ((signals & UPD78F0730_DTR) ? TIOCM_DTR : 0) |
((signals & UPD78F0730_RTS) ? TIOCM_RTS : 0);
dev_dbg(&port->dev, "%s - res = %x\n", __func__, res);
return res;
}
static int upd78f0730_tiocmset(struct tty_struct *tty,
unsigned int set, unsigned int clear)
{
struct usb_serial_port *port = tty->driver_data;
struct upd78f0730_port_private *private;
struct upd78f0730_set_dtr_rts request;
struct device *dev = &port->dev;
int res;
private = usb_get_serial_port_data(port);
mutex_lock(&private->lock);
if (set & TIOCM_DTR) {
private->line_signals |= UPD78F0730_DTR;
dev_dbg(dev, "%s - set DTR\n", __func__);
}
if (set & TIOCM_RTS) {
private->line_signals |= UPD78F0730_RTS;
dev_dbg(dev, "%s - set RTS\n", __func__);
}
if (clear & TIOCM_DTR) {
private->line_signals &= ~UPD78F0730_DTR;
dev_dbg(dev, "%s - clear DTR\n", __func__);
}
if (clear & TIOCM_RTS) {
private->line_signals &= ~UPD78F0730_RTS;
dev_dbg(dev, "%s - clear RTS\n", __func__);
}
request.opcode = UPD78F0730_CMD_SET_DTR_RTS;
request.params = private->line_signals;
res = upd78f0730_send_ctl(port, &request, sizeof(request));
mutex_unlock(&private->lock);
return res;
}
static int upd78f0730_break_ctl(struct tty_struct *tty, int break_state)
{
struct upd78f0730_port_private *private;
struct usb_serial_port *port = tty->driver_data;
struct upd78f0730_set_dtr_rts request;
struct device *dev = &port->dev;
int res;
private = usb_get_serial_port_data(port);
mutex_lock(&private->lock);
if (break_state) {
private->line_signals |= UPD78F0730_BREAK;
dev_dbg(dev, "%s - set BREAK\n", __func__);
} else {
private->line_signals &= ~UPD78F0730_BREAK;
dev_dbg(dev, "%s - clear BREAK\n", __func__);
}
request.opcode = UPD78F0730_CMD_SET_DTR_RTS;
request.params = private->line_signals;
res = upd78f0730_send_ctl(port, &request, sizeof(request));
mutex_unlock(&private->lock);
return res;
}
static void upd78f0730_dtr_rts(struct usb_serial_port *port, int on)
{
struct tty_struct *tty = port->port.tty;
unsigned int set = 0;
unsigned int clear = 0;
if (on)
set = TIOCM_DTR | TIOCM_RTS;
else
clear = TIOCM_DTR | TIOCM_RTS;
upd78f0730_tiocmset(tty, set, clear);
}
static speed_t upd78f0730_get_baud_rate(struct tty_struct *tty)
{
const speed_t baud_rate = tty_get_baud_rate(tty);
static const speed_t supported[] = {
0, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 153600
};
int i;
for (i = ARRAY_SIZE(supported) - 1; i >= 0; i--) {
if (baud_rate == supported[i])
return baud_rate;
}
/* If the baud rate is not supported, switch to the default one */
tty_encode_baud_rate(tty, 9600, 9600);
return tty_get_baud_rate(tty);
}
static void upd78f0730_set_termios(struct tty_struct *tty,
struct usb_serial_port *port,
const struct ktermios *old_termios)
{
struct device *dev = &port->dev;
struct upd78f0730_line_control request;
speed_t baud_rate;
if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios))
return;
if (C_BAUD(tty) == B0)
upd78f0730_dtr_rts(port, 0);
else if (old_termios && (old_termios->c_cflag & CBAUD) == B0)
upd78f0730_dtr_rts(port, 1);
baud_rate = upd78f0730_get_baud_rate(tty);
request.opcode = UPD78F0730_CMD_LINE_CONTROL;
request.baud_rate = cpu_to_le32(baud_rate);
request.params = 0;
dev_dbg(dev, "%s - baud rate = %d\n", __func__, baud_rate);
switch (C_CSIZE(tty)) {
case CS7:
request.params |= UPD78F0730_DATA_SIZE_7_BITS;
dev_dbg(dev, "%s - 7 data bits\n", __func__);
break;
default:
tty->termios.c_cflag &= ~CSIZE;
tty->termios.c_cflag |= CS8;
dev_warn(dev, "data size is not supported, using 8 bits\n");
fallthrough;
case CS8:
request.params |= UPD78F0730_DATA_SIZE_8_BITS;
dev_dbg(dev, "%s - 8 data bits\n", __func__);
break;
}
if (C_PARENB(tty)) {
if (C_PARODD(tty)) {
request.params |= UPD78F0730_PARITY_ODD;
dev_dbg(dev, "%s - odd parity\n", __func__);
} else {
request.params |= UPD78F0730_PARITY_EVEN;
dev_dbg(dev, "%s - even parity\n", __func__);
}
if (C_CMSPAR(tty)) {
tty->termios.c_cflag &= ~CMSPAR;
dev_warn(dev, "MARK/SPACE parity is not supported\n");
}
} else {
request.params |= UPD78F0730_PARITY_NONE;
dev_dbg(dev, "%s - no parity\n", __func__);
}
if (C_CSTOPB(tty)) {
request.params |= UPD78F0730_STOP_BIT_2_BIT;
dev_dbg(dev, "%s - 2 stop bits\n", __func__);
} else {
request.params |= UPD78F0730_STOP_BIT_1_BIT;
dev_dbg(dev, "%s - 1 stop bit\n", __func__);
}
if (C_CRTSCTS(tty)) {
tty->termios.c_cflag &= ~CRTSCTS;
dev_warn(dev, "RTSCTS flow control is not supported\n");
}
if (I_IXOFF(tty) || I_IXON(tty)) {
tty->termios.c_iflag &= ~(IXOFF | IXON);
dev_warn(dev, "XON/XOFF flow control is not supported\n");
}
request.params |= UPD78F0730_FLOW_CONTROL_NONE;
dev_dbg(dev, "%s - no flow control\n", __func__);
upd78f0730_send_ctl(port, &request, sizeof(request));
}
static int upd78f0730_open(struct tty_struct *tty, struct usb_serial_port *port)
{
static const struct upd78f0730_open_close request = {
.opcode = UPD78F0730_CMD_OPEN_CLOSE,
.state = UPD78F0730_PORT_OPEN
};
int res;
res = upd78f0730_send_ctl(port, &request, sizeof(request));
if (res)
return res;
if (tty)
upd78f0730_set_termios(tty, port, NULL);
return usb_serial_generic_open(tty, port);
}
static void upd78f0730_close(struct usb_serial_port *port)
{
static const struct upd78f0730_open_close request = {
.opcode = UPD78F0730_CMD_OPEN_CLOSE,
.state = UPD78F0730_PORT_CLOSE
};
usb_serial_generic_close(port);
upd78f0730_send_ctl(port, &request, sizeof(request));
}
static struct usb_serial_driver upd78f0730_device = {
.driver = {
.owner = THIS_MODULE,
.name = "upd78f0730",
},
.id_table = id_table,
.num_ports = 1,
.port_probe = upd78f0730_port_probe,
.port_remove = upd78f0730_port_remove,
.open = upd78f0730_open,
.close = upd78f0730_close,
.set_termios = upd78f0730_set_termios,
.tiocmget = upd78f0730_tiocmget,
.tiocmset = upd78f0730_tiocmset,
.dtr_rts = upd78f0730_dtr_rts,
.break_ctl = upd78f0730_break_ctl,
};
static struct usb_serial_driver * const serial_drivers[] = {
&upd78f0730_device,
NULL
};
module_usb_serial_driver(serial_drivers, id_table);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_LICENSE("GPL v2");