hsi.h

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/*
 * HSI core header file.
 *
 * Copyright (C) 2010 Nokia Corporation. All rights reserved.
 *
 * Contact: Carlos Chinea <[email protected]>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#ifndef __LINUX_HSI_H__
#define __LINUX_HSI_H__

#include <linux/device.h>
#include <linux/mutex.h>
#include <linux/scatterlist.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/notifier.h>

/* HSI message ttype */
#define HSI_MSG_READ    0
#define HSI_MSG_WRITE   1

/* HSI configuration values */
enum {
    HSI_MODE_STREAM = 1,
    HSI_MODE_FRAME,
};

enum {
    HSI_FLOW_SYNC,  /* Synchronized flow */
    HSI_FLOW_PIPE,  /* Pipelined flow */
};

enum {
    HSI_ARB_RR, /* Round-robin arbitration */
    HSI_ARB_PRIO,   /* Channel priority arbitration */
};

#define HSI_MAX_CHANNELS    16

/* HSI message status codes */
enum {
    HSI_STATUS_COMPLETED,   /* Message transfer is completed */
    HSI_STATUS_PENDING, /* Message pending to be read/write (POLL) */
    HSI_STATUS_PROCEEDING,  /* Message transfer is ongoing */
    HSI_STATUS_QUEUED,  /* Message waiting to be served */
    HSI_STATUS_ERROR,   /* Error when message transfer was ongoing */
};

/* HSI port event codes */
enum {
    HSI_EVENT_START_RX,
    HSI_EVENT_STOP_RX,
};

struct hsi_config {
    unsigned int    mode;
    unsigned int    channels;
    unsigned int    speed;
    union {
        unsigned int    flow;       /* RX only */
        unsigned int    arb_mode;   /* TX only */
    };
};

struct hsi_board_info {
    const char      *name;
    unsigned int        hsi_id;
    unsigned int        port;
    struct hsi_config   tx_cfg;
    struct hsi_config   rx_cfg;
    void            *platform_data;
    struct dev_archdata *archdata;
};

#ifdef CONFIG_HSI_BOARDINFO
extern int hsi_register_board_info(struct hsi_board_info const *info,
                            unsigned int len);
#else
static inline int hsi_register_board_info(struct hsi_board_info const *info,
                            unsigned int len)
{
    return 0;
}
#endif /* CONFIG_HSI_BOARDINFO */

struct hsi_client {
    struct device       device;
    struct hsi_config   tx_cfg;
    struct hsi_config   rx_cfg;
    /* private: */
    void            (*ehandler)(struct hsi_client *, unsigned long);
    unsigned int        pclaimed:1;
    struct notifier_block   nb;
};

#define to_hsi_client(dev) container_of(dev, struct hsi_client, device)

static inline void hsi_client_set_drvdata(struct hsi_client *cl, void *data)
{
    dev_set_drvdata(&cl->device, data);
}

static inline void *hsi_client_drvdata(struct hsi_client *cl)
{
    return dev_get_drvdata(&cl->device);
}

int hsi_register_port_event(struct hsi_client *cl,
            void (*handler)(struct hsi_client *, unsigned long));
int hsi_unregister_port_event(struct hsi_client *cl);

struct hsi_client_driver {
    struct device_driver    driver;
};

#define to_hsi_client_driver(drv) container_of(drv, struct hsi_client_driver,\
                                    driver)

int hsi_register_client_driver(struct hsi_client_driver *drv);

static inline void hsi_unregister_client_driver(struct hsi_client_driver *drv)
{
    driver_unregister(&drv->driver);
}

struct hsi_msg {
    struct list_head    link;
    struct hsi_client   *cl;
    struct sg_table     sgt;
    void            *context;

    void            (*complete)(struct hsi_msg *msg);
    void            (*destructor)(struct hsi_msg *msg);

    int         status;
    unsigned int        actual_len;
    unsigned int        channel;
    unsigned int        ttype:1;
    unsigned int        break_frame:1;
};

struct hsi_msg *hsi_alloc_msg(unsigned int n_frag, gfp_t flags);
void hsi_free_msg(struct hsi_msg *msg);

struct hsi_port {
    struct device           device;
    struct hsi_config       tx_cfg;
    struct hsi_config       rx_cfg;
    unsigned int            num;
    unsigned int            shared:1;
    int             claimed;
    struct mutex            lock;
    int             (*async)(struct hsi_msg *msg);
    int             (*setup)(struct hsi_client *cl);
    int             (*flush)(struct hsi_client *cl);
    int             (*start_tx)(struct hsi_client *cl);
    int             (*stop_tx)(struct hsi_client *cl);
    int             (*release)(struct hsi_client *cl);
    /* private */
    struct atomic_notifier_head n_head;
};

#define to_hsi_port(dev) container_of(dev, struct hsi_port, device)
#define hsi_get_port(cl) to_hsi_port((cl)->device.parent)

int hsi_event(struct hsi_port *port, unsigned long event);
int hsi_claim_port(struct hsi_client *cl, unsigned int share);
void hsi_release_port(struct hsi_client *cl);

static inline int hsi_port_claimed(struct hsi_client *cl)
{
    return cl->pclaimed;
}

static inline void hsi_port_set_drvdata(struct hsi_port *port, void *data)
{
    dev_set_drvdata(&port->device, data);
}

static inline void *hsi_port_drvdata(struct hsi_port *port)
{
    return dev_get_drvdata(&port->device);
}

struct hsi_controller {
    struct device       device;
    struct module       *owner;
    unsigned int        id;
    unsigned int        num_ports;
    struct hsi_port     **port;
};

#define to_hsi_controller(dev) container_of(dev, struct hsi_controller, device)

struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags);
void hsi_put_controller(struct hsi_controller *hsi);
int hsi_register_controller(struct hsi_controller *hsi);
void hsi_unregister_controller(struct hsi_controller *hsi);

static inline void hsi_controller_set_drvdata(struct hsi_controller *hsi,
                                void *data)
{
    dev_set_drvdata(&hsi->device, data);
}

static inline void *hsi_controller_drvdata(struct hsi_controller *hsi)
{
    return dev_get_drvdata(&hsi->device);
}

static inline struct hsi_port *hsi_find_port_num(struct hsi_controller *hsi,
                            unsigned int num)
{
    return (num < hsi->num_ports) ? hsi->port[num] : NULL;
}

/*
 * API for HSI clients
 */
int hsi_async(struct hsi_client *cl, struct hsi_msg *msg);

static inline unsigned int hsi_id(struct hsi_client *cl)
{
    return  to_hsi_controller(cl->device.parent->parent)->id;
}

static inline unsigned int hsi_port_id(struct hsi_client *cl)
{
    return  to_hsi_port(cl->device.parent)->num;
}

static inline int hsi_setup(struct hsi_client *cl)
{
    if (!hsi_port_claimed(cl))
        return -EACCES;
    return  hsi_get_port(cl)->setup(cl);
}

static inline int hsi_flush(struct hsi_client *cl)
{
    if (!hsi_port_claimed(cl))
        return -EACCES;
    return hsi_get_port(cl)->flush(cl);
}

static inline int hsi_async_read(struct hsi_client *cl, struct hsi_msg *msg)
{
    msg->ttype = HSI_MSG_READ;
    return hsi_async(cl, msg);
}

static inline int hsi_async_write(struct hsi_client *cl, struct hsi_msg *msg)
{
    msg->ttype = HSI_MSG_WRITE;
    return hsi_async(cl, msg);
}

static inline int hsi_start_tx(struct hsi_client *cl)
{
    if (!hsi_port_claimed(cl))
        return -EACCES;
    return hsi_get_port(cl)->start_tx(cl);
}

static inline int hsi_stop_tx(struct hsi_client *cl)
{
    if (!hsi_port_claimed(cl))
        return -EACCES;
    return hsi_get_port(cl)->stop_tx(cl);
}
#endif /* __LINUX_HSI_H__ */