/*
* Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#ifndef _LINUX_SERDEV_H
#define _LINUX_SERDEV_H
#include <linux/types.h>
#include <linux/device.h>
#include <linux/termios.h>
#include <linux/delay.h>
struct serdev_controller;
struct serdev_device;
/*
* serdev device structures
*/
/**
* struct serdev_device_ops - Callback operations for a serdev device
* @receive_buf: Function called with data received from device.
* @write_wakeup: Function called when ready to transmit more data.
*/
struct serdev_device_ops {
int (*receive_buf)(struct serdev_device *, const unsigned char *, size_t);
void (*write_wakeup)(struct serdev_device *);
};
/**
* struct serdev_device - Basic representation of an serdev device
* @dev: Driver model representation of the device.
* @nr: Device number on serdev bus.
* @ctrl: serdev controller managing this device.
* @ops: Device operations.
* @write_comp Completion used by serdev_device_write() internally
* @write_lock Lock to serialize access when writing data
*/
struct serdev_device {
struct device dev;
int nr;
struct serdev_controller *ctrl;
const struct serdev_device_ops *ops;
struct completion write_comp;
struct mutex write_lock;
};
static inline struct serdev_device *to_serdev_device(struct device *d)
{
return container_of(d, struct serdev_device, dev);
}
/**
* struct serdev_device_driver - serdev slave device driver
* @driver: serdev device drivers should initialize name field of this
* structure.
* @probe: binds this driver to a serdev device.
* @remove: unbinds this driver from the serdev device.
*/
struct serdev_device_driver {
struct device_driver driver;
int (*probe)(struct serdev_device *);
void (*remove)(struct serdev_device *);
};
static inline struct serdev_device_driver *to_serdev_device_driver(struct device_driver *d)
{
return container_of(d, struct serdev_device_driver, driver);
}
/*
* serdev controller structures
*/
struct serdev_controller_ops {
int (*write_buf)(struct serdev_controller *, const unsigned char *, size_t);
void (*write_flush)(struct serdev_controller *);
int (*write_room)(struct serdev_controller *);
int (*open)(struct serdev_controller *);
void (*close)(struct serdev_controller *);
void (*set_flow_control)(struct serdev_controller *, bool);
unsigned int (*set_baudrate)(struct serdev_controller *, unsigned int);
void (*wait_until_sent)(struct serdev_controller *, long);
int (*get_tiocm)(struct serdev_controller *);
int (*set_tiocm)(struct serdev_controller *, unsigned int, unsigned int);
};
/**
* struct serdev_controller - interface to the serdev controller
* @dev: Driver model representation of the device.
* @nr: number identifier for this controller/bus.
* @serdev: Pointer to slave device for this controller.
* @ops: Controller operations.
*/
struct serdev_controller {
struct device dev;
unsigned int nr;
struct serdev_device *serdev;
const struct serdev_controller_ops *ops;
};
static inline struct serdev_controller *to_serdev_controller(struct device *d)
{
return container_of(d, struct serdev_controller, dev);
}
static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev)
{
return dev_get_drvdata(&serdev->dev);
}
static inline void serdev_device_set_drvdata(struct serdev_device *serdev, void *data)
{
dev_set_drvdata(&serdev->dev, data);
}
/**
* serdev_device_put() - decrement serdev device refcount
* @serdev serdev device.
*/
static inline void serdev_device_put(struct serdev_device *serdev)
{
if (serdev)
put_device(&serdev->dev);
}
static inline void serdev_device_set_client_ops(struct serdev_device *serdev,
const struct serdev_device_ops *ops)
{
serdev->ops = ops;
}
static inline
void *serdev_controller_get_drvdata(const struct serdev_controller *ctrl)
{
return ctrl ? dev_get_drvdata(&ctrl->dev) : NULL;
}
static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl,
void *data)
{
dev_set_drvdata(&ctrl->dev, data);
}
/**
* serdev_controller_put() - decrement controller refcount
* @ctrl serdev controller.
*/
static inline void serdev_controller_put(struct serdev_controller *ctrl)
{
if (ctrl)
put_device(&ctrl->dev);
}
struct serdev_device *serdev_device_alloc(struct serdev_controller *);
int serdev_device_add(struct serdev_device *);
void serdev_device_remove(struct serdev_device *);
struct serdev_controller *serdev_controller_alloc(struct device *, size_t);
int serdev_controller_add(struct serdev_controller *);
void serdev_controller_remove(struct serdev_controller *);
static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl)
{
struct serdev_device *serdev = ctrl->serdev;
if (!serdev || !serdev->ops->write_wakeup)
return;
serdev->ops->write_wakeup(serdev);
}
static inline int serdev_controller_receive_buf(struct serdev_controller *ctrl,
const unsigned char *data,
size_t count)
{
struct serdev_device *serdev = ctrl->serdev;
if (!serdev || !serdev->ops->receive_buf)
return 0;
return serdev->ops->receive_buf(serdev, data, count);
}
#if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
int serdev_device_open(struct serdev_device *);
void serdev_device_close(struct serdev_device *);
unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int);
void serdev_device_set_flow_control(struct serdev_device *, bool);
int serdev_device_write_buf(struct serdev_device *, const unsigned char *, size_t);
void serdev_device_wait_until_sent(struct serdev_device *, long);
int serdev_device_get_tiocm(struct serdev_device *);
int serdev_device_set_tiocm(struct serdev_device *, int, int);
void serdev_device_write_wakeup(struct serdev_device *);
int serdev_device_write(struct serdev_device *, const unsigned char *, size_t, unsigned long);
void serdev_device_write_flush(struct serdev_device *);
int serdev_device_write_room(struct serdev_device *);
/*
* serdev device driver functions
*/
int __serdev_device_driver_register(struct serdev_device_driver *, struct module *);
#define serdev_device_driver_register(sdrv) \
__serdev_device_driver_register(sdrv, THIS_MODULE)
/**
* serdev_device_driver_unregister() - unregister an serdev client driver
* @sdrv: the driver to unregister
*/
static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv)
{
if (sdrv)
driver_unregister(&sdrv->driver);
}
#define module_serdev_device_driver(__serdev_device_driver) \
module_driver(__serdev_device_driver, serdev_device_driver_register, \
serdev_device_driver_unregister)
#else
static inline int serdev_device_open(struct serdev_device *sdev)
{
return -ENODEV;
}
static inline void serdev_device_close(struct serdev_device *sdev) {}
static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate)
{
return 0;
}
static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {}
static inline int serdev_device_write_buf(struct serdev_device *serdev,
const unsigned char *buf,
size_t count)
{
return -ENODEV;
}
static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {}
static inline int serdev_device_get_tiocm(struct serdev_device *serdev)
{
return -ENOTSUPP;
}
static inline int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear)
{
return -ENOTSUPP;
}
static inline int serdev_device_write(struct serdev_device *sdev, const unsigned char *buf,
size_t count, unsigned long timeout)
{
return -ENODEV;
}
static inline void serdev_device_write_flush(struct serdev_device *sdev) {}
static inline int serdev_device_write_room(struct serdev_device *sdev)
{
return 0;
}
#define serdev_device_driver_register(x)
#define serdev_device_driver_unregister(x)
#endif /* CONFIG_SERIAL_DEV_BUS */
static inline bool serdev_device_get_cts(struct serdev_device *serdev)
{
int status = serdev_device_get_tiocm(serdev);
return !!(status & TIOCM_CTS);
}
static inline int serdev_device_wait_for_cts(struct serdev_device *serdev, bool state, int timeout_ms)
{
unsigned long timeout;
bool signal;
timeout = jiffies + msecs_to_jiffies(timeout_ms);
while (time_is_after_jiffies(timeout)) {
signal = serdev_device_get_cts(serdev);
if (signal == state)
return 0;
usleep_range(1000, 2000);
}
return -ETIMEDOUT;
}
static inline int serdev_device_set_rts(struct serdev_device *serdev, bool enable)
{
if (enable)
return serdev_device_set_tiocm(serdev, TIOCM_RTS, 0);
else
return serdev_device_set_tiocm(serdev, 0, TIOCM_RTS);
}
/*
* serdev hooks into TTY core
*/
struct tty_port;
struct tty_driver;
#ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT
struct device *serdev_tty_port_register(struct tty_port *port,
struct device *parent,
struct tty_driver *drv, int idx);
int serdev_tty_port_unregister(struct tty_port *port);
#else
static inline struct device *serdev_tty_port_register(struct tty_port *port,
struct device *parent,
struct tty_driver *drv, int idx)
{
return ERR_PTR(-ENODEV);
}
static inline int serdev_tty_port_unregister(struct tty_port *port)
{
return -ENODEV;
}
#endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */
#endif /*_LINUX_SERDEV_H */
