forked from mirrors/linux
		
	Adds serdev_device_break_ctl() and an implementation for ttyport. This function simply calls the break_ctl in tty layer, which can assert a break signal over UART-TX line, if the tty and the underlying platform and UART peripheral supports this operation. Signed-off-by: Neeraj Sanjay Kale <neeraj.sanjaykale@nxp.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
		
			
				
	
	
		
			344 lines
		
	
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			344 lines
		
	
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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 * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
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 */
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#ifndef _LINUX_SERDEV_H
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#define _LINUX_SERDEV_H
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#include <linux/types.h>
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#include <linux/device.h>
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#include <linux/iopoll.h>
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#include <linux/uaccess.h>
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#include <linux/termios.h>
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#include <linux/delay.h>
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struct serdev_controller;
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struct serdev_device;
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/*
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 * serdev device structures
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 */
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/**
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 * struct serdev_device_ops - Callback operations for a serdev device
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 * @receive_buf:	Function called with data received from device;
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 *			returns number of bytes accepted; may sleep.
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 * @write_wakeup:	Function called when ready to transmit more data; must
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 *			not sleep.
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 */
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struct serdev_device_ops {
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	int (*receive_buf)(struct serdev_device *, const unsigned char *, size_t);
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	void (*write_wakeup)(struct serdev_device *);
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};
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/**
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 * struct serdev_device - Basic representation of an serdev device
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 * @dev:	Driver model representation of the device.
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 * @nr:		Device number on serdev bus.
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 * @ctrl:	serdev controller managing this device.
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 * @ops:	Device operations.
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 * @write_comp	Completion used by serdev_device_write() internally
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 * @write_lock	Lock to serialize access when writing data
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 */
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struct serdev_device {
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	struct device dev;
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	int nr;
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	struct serdev_controller *ctrl;
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	const struct serdev_device_ops *ops;
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	struct completion write_comp;
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	struct mutex write_lock;
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};
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static inline struct serdev_device *to_serdev_device(struct device *d)
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{
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	return container_of(d, struct serdev_device, dev);
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}
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/**
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 * struct serdev_device_driver - serdev slave device driver
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 * @driver:	serdev device drivers should initialize name field of this
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 *		structure.
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 * @probe:	binds this driver to a serdev device.
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 * @remove:	unbinds this driver from the serdev device.
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 */
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struct serdev_device_driver {
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	struct device_driver driver;
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	int	(*probe)(struct serdev_device *);
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	void	(*remove)(struct serdev_device *);
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};
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static inline struct serdev_device_driver *to_serdev_device_driver(struct device_driver *d)
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{
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	return container_of(d, struct serdev_device_driver, driver);
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}
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enum serdev_parity {
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	SERDEV_PARITY_NONE,
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	SERDEV_PARITY_EVEN,
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	SERDEV_PARITY_ODD,
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};
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/*
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 * serdev controller structures
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 */
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struct serdev_controller_ops {
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	int (*write_buf)(struct serdev_controller *, const unsigned char *, size_t);
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	void (*write_flush)(struct serdev_controller *);
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	int (*write_room)(struct serdev_controller *);
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	int (*open)(struct serdev_controller *);
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	void (*close)(struct serdev_controller *);
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	void (*set_flow_control)(struct serdev_controller *, bool);
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	int (*set_parity)(struct serdev_controller *, enum serdev_parity);
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	unsigned int (*set_baudrate)(struct serdev_controller *, unsigned int);
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	void (*wait_until_sent)(struct serdev_controller *, long);
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	int (*get_tiocm)(struct serdev_controller *);
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	int (*set_tiocm)(struct serdev_controller *, unsigned int, unsigned int);
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	int (*break_ctl)(struct serdev_controller *ctrl, unsigned int break_state);
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};
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/**
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 * struct serdev_controller - interface to the serdev controller
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 * @dev:	Driver model representation of the device.
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 * @nr:		number identifier for this controller/bus.
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 * @serdev:	Pointer to slave device for this controller.
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 * @ops:	Controller operations.
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 */
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struct serdev_controller {
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	struct device		dev;
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	unsigned int		nr;
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	struct serdev_device	*serdev;
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	const struct serdev_controller_ops *ops;
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};
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static inline struct serdev_controller *to_serdev_controller(struct device *d)
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{
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	return container_of(d, struct serdev_controller, dev);
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}
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static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev)
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{
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	return dev_get_drvdata(&serdev->dev);
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}
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static inline void serdev_device_set_drvdata(struct serdev_device *serdev, void *data)
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{
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	dev_set_drvdata(&serdev->dev, data);
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}
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/**
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 * serdev_device_put() - decrement serdev device refcount
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 * @serdev	serdev device.
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 */
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static inline void serdev_device_put(struct serdev_device *serdev)
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{
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	if (serdev)
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		put_device(&serdev->dev);
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}
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static inline void serdev_device_set_client_ops(struct serdev_device *serdev,
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					      const struct serdev_device_ops *ops)
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{
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	serdev->ops = ops;
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}
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static inline
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void *serdev_controller_get_drvdata(const struct serdev_controller *ctrl)
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{
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	return ctrl ? dev_get_drvdata(&ctrl->dev) : NULL;
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}
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static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl,
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					       void *data)
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{
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	dev_set_drvdata(&ctrl->dev, data);
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}
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/**
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 * serdev_controller_put() - decrement controller refcount
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 * @ctrl	serdev controller.
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 */
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static inline void serdev_controller_put(struct serdev_controller *ctrl)
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{
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	if (ctrl)
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		put_device(&ctrl->dev);
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}
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struct serdev_device *serdev_device_alloc(struct serdev_controller *);
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int serdev_device_add(struct serdev_device *);
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void serdev_device_remove(struct serdev_device *);
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struct serdev_controller *serdev_controller_alloc(struct device *, size_t);
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int serdev_controller_add(struct serdev_controller *);
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void serdev_controller_remove(struct serdev_controller *);
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static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl)
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{
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	struct serdev_device *serdev = ctrl->serdev;
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	if (!serdev || !serdev->ops->write_wakeup)
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		return;
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	serdev->ops->write_wakeup(serdev);
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}
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static inline int serdev_controller_receive_buf(struct serdev_controller *ctrl,
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					      const unsigned char *data,
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					      size_t count)
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{
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	struct serdev_device *serdev = ctrl->serdev;
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	if (!serdev || !serdev->ops->receive_buf)
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		return 0;
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	return serdev->ops->receive_buf(serdev, data, count);
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}
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#if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
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int serdev_device_open(struct serdev_device *);
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void serdev_device_close(struct serdev_device *);
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int devm_serdev_device_open(struct device *, struct serdev_device *);
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unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int);
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void serdev_device_set_flow_control(struct serdev_device *, bool);
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int serdev_device_write_buf(struct serdev_device *, const unsigned char *, size_t);
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void serdev_device_wait_until_sent(struct serdev_device *, long);
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int serdev_device_get_tiocm(struct serdev_device *);
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int serdev_device_set_tiocm(struct serdev_device *, int, int);
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int serdev_device_break_ctl(struct serdev_device *serdev, int break_state);
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void serdev_device_write_wakeup(struct serdev_device *);
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int serdev_device_write(struct serdev_device *, const unsigned char *, size_t, long);
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void serdev_device_write_flush(struct serdev_device *);
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int serdev_device_write_room(struct serdev_device *);
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/*
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 * serdev device driver functions
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 */
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int __serdev_device_driver_register(struct serdev_device_driver *, struct module *);
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#define serdev_device_driver_register(sdrv) \
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	__serdev_device_driver_register(sdrv, THIS_MODULE)
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/**
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 * serdev_device_driver_unregister() - unregister an serdev client driver
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 * @sdrv:	the driver to unregister
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 */
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static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv)
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{
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	if (sdrv)
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		driver_unregister(&sdrv->driver);
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}
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#define module_serdev_device_driver(__serdev_device_driver) \
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	module_driver(__serdev_device_driver, serdev_device_driver_register, \
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			serdev_device_driver_unregister)
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#else
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static inline int serdev_device_open(struct serdev_device *sdev)
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{
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	return -ENODEV;
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}
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static inline void serdev_device_close(struct serdev_device *sdev) {}
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static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate)
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{
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	return 0;
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}
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static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {}
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static inline int serdev_device_write_buf(struct serdev_device *serdev,
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					  const unsigned char *buf,
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					  size_t count)
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{
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	return -ENODEV;
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}
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static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {}
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static inline int serdev_device_get_tiocm(struct serdev_device *serdev)
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{
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	return -EOPNOTSUPP;
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}
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static inline int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear)
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{
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	return -EOPNOTSUPP;
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}
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static inline int serdev_device_break_ctl(struct serdev_device *serdev, int break_state)
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{
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	return -EOPNOTSUPP;
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}
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static inline int serdev_device_write(struct serdev_device *sdev, const unsigned char *buf,
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				      size_t count, unsigned long timeout)
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{
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	return -ENODEV;
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}
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static inline void serdev_device_write_flush(struct serdev_device *sdev) {}
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static inline int serdev_device_write_room(struct serdev_device *sdev)
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{
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	return 0;
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}
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#define serdev_device_driver_register(x)
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#define serdev_device_driver_unregister(x)
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#endif /* CONFIG_SERIAL_DEV_BUS */
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static inline bool serdev_device_get_cts(struct serdev_device *serdev)
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{
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	int status = serdev_device_get_tiocm(serdev);
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	return !!(status & TIOCM_CTS);
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}
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static inline int serdev_device_wait_for_cts(struct serdev_device *serdev, bool state, int timeout_ms)
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{
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	bool signal;
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	return readx_poll_timeout(serdev_device_get_cts, serdev, signal, signal == state,
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				  2000, timeout_ms * 1000);
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}
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static inline int serdev_device_set_rts(struct serdev_device *serdev, bool enable)
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{
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	if (enable)
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		return serdev_device_set_tiocm(serdev, TIOCM_RTS, 0);
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	else
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		return serdev_device_set_tiocm(serdev, 0, TIOCM_RTS);
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}
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int serdev_device_set_parity(struct serdev_device *serdev,
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			     enum serdev_parity parity);
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/*
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 * serdev hooks into TTY core
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 */
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struct tty_port;
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struct tty_driver;
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#ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT
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struct device *serdev_tty_port_register(struct tty_port *port,
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					struct device *parent,
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					struct tty_driver *drv, int idx);
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int serdev_tty_port_unregister(struct tty_port *port);
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#else
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static inline struct device *serdev_tty_port_register(struct tty_port *port,
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					   struct device *parent,
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					   struct tty_driver *drv, int idx)
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{
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	return ERR_PTR(-ENODEV);
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}
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static inline int serdev_tty_port_unregister(struct tty_port *port)
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{
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	return -ENODEV;
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}
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#endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */
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struct acpi_resource;
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struct acpi_resource_uart_serialbus;
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#ifdef CONFIG_ACPI
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bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
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				   struct acpi_resource_uart_serialbus **uart);
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#else
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static inline bool serdev_acpi_get_uart_resource(struct acpi_resource *ares,
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						 struct acpi_resource_uart_serialbus **uart)
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{
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	return false;
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}
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#endif /* CONFIG_ACPI */
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#endif /*_LINUX_SERDEV_H */
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