[mirror_ubuntu-bionic-kernel.git] / include / linux / serdev.h

/*
 * 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 */
Commit	Line	Data
cd6484e1 RH	1	/*
	2	* Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 and
	6	* only version 2 as published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful,
	9	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	11	* GNU General Public License for more details.
	12	*/
	13	#ifndef _LINUX_SERDEV_H
	14	#define _LINUX_SERDEV_H
	15
	16	#include <linux/types.h>
	17	#include <linux/device.h>
5659dab2	18	#include <linux/termios.h>
756db778	19	#include <linux/delay.h>
cd6484e1 RH	20
	21	struct serdev_controller;
	22	struct serdev_device;
	23
	24	/*
	25	* serdev device structures
	26	*/
	27
	28	/**
	29	* struct serdev_device_ops - Callback operations for a serdev device
	30	* @receive_buf: Function called with data received from device.
	31	* @write_wakeup: Function called when ready to transmit more data.
	32	*/
	33	struct serdev_device_ops {
	34	int (receive_buf)(struct serdev_device , const unsigned char *, size_t);
	35	void (write_wakeup)(struct serdev_device );
	36	};
	37
	38	/**
	39	* struct serdev_device - Basic representation of an serdev device
	40	* @dev: Driver model representation of the device.
	41	* @nr: Device number on serdev bus.
	42	* @ctrl: serdev controller managing this device.
	43	* @ops: Device operations.
6fe729c4 AS	44	* @write_comp Completion used by serdev_device_write() internally
6fe729c4 AS	45	* @write_lock Lock to serialize access when writing data
cd6484e1 RH	46	*/
	47	struct serdev_device {
	48	struct device dev;
	49	int nr;
	50	struct serdev_controller *ctrl;
	51	const struct serdev_device_ops *ops;
6fe729c4 AS	52	struct completion write_comp;
6fe729c4 AS	53	struct mutex write_lock;
cd6484e1 RH	54	};
	55
	56	static inline struct serdev_device to_serdev_device(struct device d)
	57	{
	58	return container_of(d, struct serdev_device, dev);
	59	}
	60
	61	/**
	62	* struct serdev_device_driver - serdev slave device driver
	63	* @driver: serdev device drivers should initialize name field of this
	64	* structure.
	65	* @probe: binds this driver to a serdev device.
	66	* @remove: unbinds this driver from the serdev device.
	67	*/
	68	struct serdev_device_driver {
	69	struct device_driver driver;
	70	int (probe)(struct serdev_device );
	71	void (remove)(struct serdev_device );
	72	};
	73
	74	static inline struct serdev_device_driver to_serdev_device_driver(struct device_driver d)
	75	{
	76	return container_of(d, struct serdev_device_driver, driver);
	77	}
	78
	79	/*
	80	* serdev controller structures
	81	*/
	82	struct serdev_controller_ops {
	83	int (write_buf)(struct serdev_controller , const unsigned char *, size_t);
	84	void (write_flush)(struct serdev_controller );
	85	int (write_room)(struct serdev_controller );
	86	int (open)(struct serdev_controller );
	87	void (close)(struct serdev_controller );
	88	void (set_flow_control)(struct serdev_controller , bool);
	89	unsigned int (set_baudrate)(struct serdev_controller , unsigned int);
b3f80c8f	90	void (wait_until_sent)(struct serdev_controller , long);
5659dab2 SR	91	int (get_tiocm)(struct serdev_controller );
5659dab2 SR	92	int (set_tiocm)(struct serdev_controller , unsigned int, unsigned int);
cd6484e1 RH	93	};
	94
	95	/**
	96	* struct serdev_controller - interface to the serdev controller
	97	* @dev: Driver model representation of the device.
	98	* @nr: number identifier for this controller/bus.
	99	* @serdev: Pointer to slave device for this controller.
	100	* @ops: Controller operations.
	101	*/
	102	struct serdev_controller {
	103	struct device dev;
	104	unsigned int nr;
	105	struct serdev_device *serdev;
	106	const struct serdev_controller_ops *ops;
	107	};
	108
	109	static inline struct serdev_controller to_serdev_controller(struct device d)
	110	{
	111	return container_of(d, struct serdev_controller, dev);
	112	}
	113
	114	static inline void serdev_device_get_drvdata(const struct serdev_device serdev)
	115	{
	116	return dev_get_drvdata(&serdev->dev);
	117	}
	118
	119	static inline void serdev_device_set_drvdata(struct serdev_device serdev, void data)
	120	{
	121	dev_set_drvdata(&serdev->dev, data);
	122	}
	123
	124	/**
	125	* serdev_device_put() - decrement serdev device refcount
	126	* @serdev serdev device.
	127	*/
	128	static inline void serdev_device_put(struct serdev_device *serdev)
	129	{
	130	if (serdev)
	131	put_device(&serdev->dev);
	132	}
	133
	134	static inline void serdev_device_set_client_ops(struct serdev_device *serdev,
	135	const struct serdev_device_ops *ops)
	136	{
	137	serdev->ops = ops;
	138	}
	139
	140	static inline
	141	void serdev_controller_get_drvdata(const struct serdev_controller ctrl)
	142	{
	143	return ctrl ? dev_get_drvdata(&ctrl->dev) : NULL;
	144	}
	145
	146	static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl,
	147	void *data)
	148	{
	149	dev_set_drvdata(&ctrl->dev, data);
	150	}
	151
	152	/**
	153	* serdev_controller_put() - decrement controller refcount
	154	* @ctrl serdev controller.
	155	*/
	156	static inline void serdev_controller_put(struct serdev_controller *ctrl)
157	{
158	if (ctrl)
159	put_device(&ctrl->dev);
160	}
161
162	struct serdev_device serdev_device_alloc(struct serdev_controller );
163	int serdev_device_add(struct serdev_device *);
164	void serdev_device_remove(struct serdev_device *);
165
166	struct serdev_controller serdev_controller_alloc(struct device , size_t);
167	int serdev_controller_add(struct serdev_controller *);
168	void serdev_controller_remove(struct serdev_controller *);
169
170	static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl)
171	{
172	struct serdev_device *serdev = ctrl->serdev;
173
174	if (!serdev \|\| !serdev->ops->write_wakeup)
175	return;
176
9d1d994d	177	serdev->ops->write_wakeup(serdev);
cd6484e1 RH	178	}
	179
	180	static inline int serdev_controller_receive_buf(struct serdev_controller *ctrl,
	181	const unsigned char *data,
	182	size_t count)
	183	{
	184	struct serdev_device *serdev = ctrl->serdev;
	185
	186	if (!serdev \|\| !serdev->ops->receive_buf)
fd00cf81	187	return 0;
cd6484e1	188
9d1d994d	189	return serdev->ops->receive_buf(serdev, data, count);
cd6484e1 RH	190	}
	191
	192	#if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
	193
	194	int serdev_device_open(struct serdev_device *);
	195	void serdev_device_close(struct serdev_device *);
	196	unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int);
	197	void serdev_device_set_flow_control(struct serdev_device *, bool);
6bdc00d0	198	int serdev_device_write_buf(struct serdev_device , const unsigned char , size_t);
b3f80c8f	199	void serdev_device_wait_until_sent(struct serdev_device *, long);
5659dab2 SR	200	int serdev_device_get_tiocm(struct serdev_device *);
5659dab2 SR	201	int serdev_device_set_tiocm(struct serdev_device *, int, int);
6fe729c4 AS	202	void serdev_device_write_wakeup(struct serdev_device *);
6fe729c4 AS	203	int serdev_device_write(struct serdev_device , const unsigned char , size_t, unsigned long);
cd6484e1 RH	204	void serdev_device_write_flush(struct serdev_device *);
	205	int serdev_device_write_room(struct serdev_device *);
	206
	207	/*
	208	* serdev device driver functions
	209	*/
	210	int __serdev_device_driver_register(struct serdev_device_driver , struct module );
	211	#define serdev_device_driver_register(sdrv) \
	212	__serdev_device_driver_register(sdrv, THIS_MODULE)
	213
	214	/**
	215	* serdev_device_driver_unregister() - unregister an serdev client driver
	216	* @sdrv: the driver to unregister
	217	*/
	218	static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv)
	219	{
	220	if (sdrv)
	221	driver_unregister(&sdrv->driver);
	222	}
	223
	224	#define module_serdev_device_driver(__serdev_device_driver) \
	225	module_driver(__serdev_device_driver, serdev_device_driver_register, \
	226	serdev_device_driver_unregister)
	227
	228	#else
	229
	230	static inline int serdev_device_open(struct serdev_device *sdev)
	231	{
	232	return -ENODEV;
	233	}
	234	static inline void serdev_device_close(struct serdev_device *sdev) {}
	235	static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate)
	236	{
	237	return 0;
	238	}
	239	static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {}
6bdc00d0 SW	240	static inline int serdev_device_write_buf(struct serdev_device *serdev,
	241	const unsigned char *buf,
	242	size_t count)
	243	{
	244	return -ENODEV;
	245	}
b3f80c8f	246	static inline void serdev_device_wait_until_sent(struct serdev_device *sdev, long timeout) {}
5659dab2 SR	247	static inline int serdev_device_get_tiocm(struct serdev_device *serdev)
	248	{
	249	return -ENOTSUPP;
	250	}
	251	static inline int serdev_device_set_tiocm(struct serdev_device *serdev, int set, int clear)
	252	{
	253	return -ENOTSUPP;
	254	}
6fe729c4 AS	255	static inline int serdev_device_write(struct serdev_device sdev, const unsigned char buf,
6fe729c4 AS	256	size_t count, unsigned long timeout)
cd6484e1 RH	257	{
	258	return -ENODEV;
	259	}
	260	static inline void serdev_device_write_flush(struct serdev_device *sdev) {}
	261	static inline int serdev_device_write_room(struct serdev_device *sdev)
	262	{
	263	return 0;
	264	}
	265
	266	#define serdev_device_driver_register(x)
	267	#define serdev_device_driver_unregister(x)
	268
	269	#endif /* CONFIG_SERIAL_DEV_BUS */
	270
756db778 SR	271	static inline bool serdev_device_get_cts(struct serdev_device *serdev)
	272	{
	273	int status = serdev_device_get_tiocm(serdev);
	274	return !!(status & TIOCM_CTS);
	275	}
	276
	277	static inline int serdev_device_wait_for_cts(struct serdev_device *serdev, bool state, int timeout_ms)
	278	{
	279	unsigned long timeout;
	280	bool signal;
	281
	282	timeout = jiffies + msecs_to_jiffies(timeout_ms);
	283	while (time_is_after_jiffies(timeout)) {
	284	signal = serdev_device_get_cts(serdev);
	285	if (signal == state)
	286	return 0;
	287	usleep_range(1000, 2000);
	288	}
	289
	290	return -ETIMEDOUT;
	291	}
	292
	293	static inline int serdev_device_set_rts(struct serdev_device *serdev, bool enable)
	294	{
	295	if (enable)
	296	return serdev_device_set_tiocm(serdev, TIOCM_RTS, 0);
	297	else
	298	return serdev_device_set_tiocm(serdev, 0, TIOCM_RTS);
	299	}
	300
bed35c6d RH	301	/*
	302	* serdev hooks into TTY core
	303	*/
	304	struct tty_port;
	305	struct tty_driver;
	306
	307	#ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT
	308	struct device serdev_tty_port_register(struct tty_port port,
	309	struct device *parent,
	310	struct tty_driver *drv, int idx);
8cde11b2	311	int serdev_tty_port_unregister(struct tty_port *port);
bed35c6d RH	312	#else
	313	static inline struct device serdev_tty_port_register(struct tty_port port,
	314	struct device *parent,
	315	struct tty_driver *drv, int idx)
	316	{
	317	return ERR_PTR(-ENODEV);
	318	}
8cde11b2 JH	319	static inline int serdev_tty_port_unregister(struct tty_port *port)
	320	{
	321	return -ENODEV;
	322	}
bed35c6d RH	323	#endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */
bed35c6d RH	324
cd6484e1	325	#endif /_LINUX_SERDEV_H /