include/linux/hsi/hsi.h

   1 /*
   2  * HSI core header file.
   3  *
   4  * Copyright (C) 2010 Nokia Corporation. All rights reserved.
   5  *
   6  * Contact: Carlos Chinea <carlos.chinea@nokia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  20  * 02110-1301 USA
  21  */
  22
  23 #ifndef __LINUX_HSI_H__
  24 #define __LINUX_HSI_H__
  25
  26 #include <linux/device.h>
  27 #include <linux/mutex.h>
  28 #include <linux/scatterlist.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/list.h>
  31 #include <linux/module.h>
  32
  33 /* HSI message ttype */
  34 #define HSI_MSG_READ    0
  35 #define HSI_MSG_WRITE   1
  36
  37 /* HSI configuration values */
  38 enum {
  39         HSI_MODE_STREAM = 1,
  40         HSI_MODE_FRAME,
  41 };
  42
  43 enum {
  44         HSI_FLOW_SYNC,  /* Synchronized flow */
  45         HSI_FLOW_PIPE,  /* Pipelined flow */
  46 };
  47
  48 enum {
  49         HSI_ARB_RR,     /* Round-robin arbitration */
  50         HSI_ARB_PRIO,   /* Channel priority arbitration */
  51 };
  52
  53 #define HSI_MAX_CHANNELS        16
  54
  55 /* HSI message status codes */
  56 enum {
  57         HSI_STATUS_COMPLETED,   /* Message transfer is completed */
  58         HSI_STATUS_PENDING,     /* Message pending to be read/write (POLL) */
  59         HSI_STATUS_PROCEEDING,  /* Message transfer is ongoing */
  60         HSI_STATUS_QUEUED,      /* Message waiting to be served */
  61         HSI_STATUS_ERROR,       /* Error when message transfer was ongoing */
  62 };
  63
  64 /* HSI port event codes */
  65 enum {
  66         HSI_EVENT_START_RX,
  67         HSI_EVENT_STOP_RX,
  68 };
  69
  70 /**
  71  * struct hsi_config - Configuration for RX/TX HSI modules
  72  * @mode: Bit transmission mode (STREAM or FRAME)
  73  * @channels: Number of channels to use [1..16]
  74  * @speed: Max bit transmission speed (Kbit/s)
  75  * @flow: RX flow type (SYNCHRONIZED or PIPELINE)
  76  * @arb_mode: Arbitration mode for TX frame (Round robin, priority)
  77  */
  78 struct hsi_config {
  79         unsigned int    mode;
  80         unsigned int    channels;
  81         unsigned int    speed;
  82         union {
  83                 unsigned int    flow;           /* RX only */
  84                 unsigned int    arb_mode;       /* TX only */
  85         };
  86 };
  87
  88 /**
  89  * struct hsi_board_info - HSI client board info
  90  * @name: Name for the HSI device
  91  * @hsi_id: HSI controller id where the client sits
  92  * @port: Port number in the controller where the client sits
  93  * @tx_cfg: HSI TX configuration
  94  * @rx_cfg: HSI RX configuration
  95  * @platform_data: Platform related data
  96  * @archdata: Architecture-dependent device data
  97  */
  98 struct hsi_board_info {
  99         const char              *name;
 100         unsigned int            hsi_id;
 101         unsigned int            port;
 102         struct hsi_config       tx_cfg;
 103         struct hsi_config       rx_cfg;
 104         void                    *platform_data;
 105         struct dev_archdata     *archdata;
 106 };
 107
 108 #ifdef CONFIG_HSI_BOARDINFO
 109 extern int hsi_register_board_info(struct hsi_board_info const *info,
 110                                                         unsigned int len);
 111 #else
 112 static inline int hsi_register_board_info(struct hsi_board_info const *info,
 113                                                         unsigned int len)
 114 {
 115         return 0;
 116 }
 117 #endif /* CONFIG_HSI_BOARDINFO */
 118
 119 /**
 120  * struct hsi_client - HSI client attached to an HSI port
 121  * @device: Driver model representation of the device
 122  * @tx_cfg: HSI TX configuration
 123  * @rx_cfg: HSI RX configuration
 124  * @hsi_start_rx: Called after incoming wake line goes high
 125  * @hsi_stop_rx: Called after incoming wake line goes low
 126  */
 127 struct hsi_client {
 128         struct device           device;
 129         struct hsi_config       tx_cfg;
 130         struct hsi_config       rx_cfg;
 131         void                    (*hsi_start_rx)(struct hsi_client *cl);
 132         void                    (*hsi_stop_rx)(struct hsi_client *cl);
 133         /* private: */
 134         unsigned int            pclaimed:1;
 135         struct list_head        link;
 136 };
 137
 138 #define to_hsi_client(dev) container_of(dev, struct hsi_client, device)
 139
 140 static inline void hsi_client_set_drvdata(struct hsi_client *cl, void *data)
 141 {
 142         dev_set_drvdata(&cl->device, data);
 143 }
 144
 145 static inline void *hsi_client_drvdata(struct hsi_client *cl)
 146 {
 147         return dev_get_drvdata(&cl->device);
 148 }
 149
 150 /**
 151  * struct hsi_client_driver - Driver associated to an HSI client
 152  * @driver: Driver model representation of the driver
 153  */
 154 struct hsi_client_driver {
 155         struct device_driver    driver;
 156 };
 157
 158 #define to_hsi_client_driver(drv) container_of(drv, struct hsi_client_driver,\
 159                                                                         driver)
 160
 161 int hsi_register_client_driver(struct hsi_client_driver *drv);
 162
 163 static inline void hsi_unregister_client_driver(struct hsi_client_driver *drv)
 164 {
 165         driver_unregister(&drv->driver);
 166 }
 167
 168 /**
 169  * struct hsi_msg - HSI message descriptor
 170  * @link: Free to use by the current descriptor owner
 171  * @cl: HSI device client that issues the transfer
 172  * @sgt: Head of the scatterlist array
 173  * @context: Client context data associated to the transfer
 174  * @complete: Transfer completion callback
 175  * @destructor: Destructor to free resources when flushing
 176  * @status: Status of the transfer when completed
 177  * @actual_len: Actual length of data transfered on completion
 178  * @channel: Channel were to TX/RX the message
 179  * @ttype: Transfer type (TX if set, RX otherwise)
 180  * @break_frame: if true HSI will send/receive a break frame. Data buffers are
 181  *              ignored in the request.
 182  */
 183 struct hsi_msg {
 184         struct list_head        link;
 185         struct hsi_client       *cl;
 186         struct sg_table         sgt;
 187         void                    *context;
 188
 189         void                    (*complete)(struct hsi_msg *msg);
 190         void                    (*destructor)(struct hsi_msg *msg);
 191
 192         int                     status;
 193         unsigned int            actual_len;
 194         unsigned int            channel;
 195         unsigned int            ttype:1;
 196         unsigned int            break_frame:1;
 197 };
 198
 199 struct hsi_msg *hsi_alloc_msg(unsigned int n_frag, gfp_t flags);
 200 void hsi_free_msg(struct hsi_msg *msg);
 201
 202 /**
 203  * struct hsi_port - HSI port device
 204  * @device: Driver model representation of the device
 205  * @tx_cfg: Current TX path configuration
 206  * @rx_cfg: Current RX path configuration
 207  * @num: Port number
 208  * @shared: Set when port can be shared by different clients
 209  * @claimed: Reference count of clients which claimed the port
 210  * @lock: Serialize port claim
 211  * @async: Asynchronous transfer callback
 212  * @setup: Callback to set the HSI client configuration
 213  * @flush: Callback to clean the HW state and destroy all pending transfers
 214  * @start_tx: Callback to inform that a client wants to TX data
 215  * @stop_tx: Callback to inform that a client no longer wishes to TX data
 216  * @release: Callback to inform that a client no longer uses the port
 217  * @clients: List of hsi_clients using the port.
 218  * @clock: Lock to serialize access to the clients list.
 219  */
 220 struct hsi_port {
 221         struct device                   device;
 222         struct hsi_config               tx_cfg;
 223         struct hsi_config               rx_cfg;
 224         unsigned int                    num;
 225         unsigned int                    shared:1;
 226         int                             claimed;
 227         struct mutex                    lock;
 228         int                             (*async)(struct hsi_msg *msg);
 229         int                             (*setup)(struct hsi_client *cl);
 230         int                             (*flush)(struct hsi_client *cl);
 231         int                             (*start_tx)(struct hsi_client *cl);
 232         int                             (*stop_tx)(struct hsi_client *cl);
 233         int                             (*release)(struct hsi_client *cl);
 234         struct list_head                clients;
 235         spinlock_t                      clock;
 236 };
 237
 238 #define to_hsi_port(dev) container_of(dev, struct hsi_port, device)
 239 #define hsi_get_port(cl) to_hsi_port((cl)->device.parent)
 240
 241 void hsi_event(struct hsi_port *port, unsigned int event);
 242 int hsi_claim_port(struct hsi_client *cl, unsigned int share);
 243 void hsi_release_port(struct hsi_client *cl);
 244
 245 static inline int hsi_port_claimed(struct hsi_client *cl)
 246 {
 247         return cl->pclaimed;
 248 }
 249
 250 static inline void hsi_port_set_drvdata(struct hsi_port *port, void *data)
 251 {
 252         dev_set_drvdata(&port->device, data);
 253 }
 254
 255 static inline void *hsi_port_drvdata(struct hsi_port *port)
 256 {
 257         return dev_get_drvdata(&port->device);
 258 }
 259
 260 /**
 261  * struct hsi_controller - HSI controller device
 262  * @device: Driver model representation of the device
 263  * @owner: Pointer to the module owning the controller
 264  * @id: HSI controller ID
 265  * @num_ports: Number of ports in the HSI controller
 266  * @port: Array of HSI ports
 267  */
 268 struct hsi_controller {
 269         struct device           device;
 270         struct module           *owner;
 271         unsigned int            id;
 272         unsigned int            num_ports;
 273         struct hsi_port         *port;
 274 };
 275
 276 #define to_hsi_controller(dev) container_of(dev, struct hsi_controller, device)
 277
 278 struct hsi_controller *hsi_alloc_controller(unsigned int n_ports, gfp_t flags);
 279 void hsi_free_controller(struct hsi_controller *hsi);
 280 int hsi_register_controller(struct hsi_controller *hsi);
 281 void hsi_unregister_controller(struct hsi_controller *hsi);
 282
 283 static inline void hsi_controller_set_drvdata(struct hsi_controller *hsi,
 284                                                                 void *data)
 285 {
 286         dev_set_drvdata(&hsi->device, data);
 287 }
 288
 289 static inline void *hsi_controller_drvdata(struct hsi_controller *hsi)
 290 {
 291         return dev_get_drvdata(&hsi->device);
 292 }
 293
 294 static inline struct hsi_port *hsi_find_port_num(struct hsi_controller *hsi,
 295                                                         unsigned int num)
 296 {
 297         return (num < hsi->num_ports) ? &hsi->port[num] : NULL;
 298 }
 299
 300 /*
 301  * API for HSI clients
 302  */
 303 int hsi_async(struct hsi_client *cl, struct hsi_msg *msg);
 304
 305 /**
 306  * hsi_id - Get HSI controller ID associated to a client
 307  * @cl: Pointer to a HSI client
 308  *
 309  * Return the controller id where the client is attached to
 310  */
 311 static inline unsigned int hsi_id(struct hsi_client *cl)
 312 {
 313         return  to_hsi_controller(cl->device.parent->parent)->id;
 314 }
 315
 316 /**
 317  * hsi_port_id - Gets the port number a client is attached to
 318  * @cl: Pointer to HSI client
 319  *
 320  * Return the port number associated to the client
 321  */
 322 static inline unsigned int hsi_port_id(struct hsi_client *cl)
 323 {
 324         return  to_hsi_port(cl->device.parent)->num;
 325 }
 326
 327 /**
 328  * hsi_setup - Configure the client's port
 329  * @cl: Pointer to the HSI client
 330  *
 331  * When sharing ports, clients should either relay on a single
 332  * client setup or have the same setup for all of them.
 333  *
 334  * Return -errno on failure, 0 on success
 335  */
 336 static inline int hsi_setup(struct hsi_client *cl)
 337 {
 338         if (!hsi_port_claimed(cl))
 339                 return -EACCES;
 340         return  hsi_get_port(cl)->setup(cl);
 341 }
 342
 343 /**
 344  * hsi_flush - Flush all pending transactions on the client's port
 345  * @cl: Pointer to the HSI client
 346  *
 347  * This function will destroy all pending hsi_msg in the port and reset
 348  * the HW port so it is ready to receive and transmit from a clean state.
 349  *
 350  * Return -errno on failure, 0 on success
 351  */
 352 static inline int hsi_flush(struct hsi_client *cl)
 353 {
 354         if (!hsi_port_claimed(cl))
 355                 return -EACCES;
 356         return hsi_get_port(cl)->flush(cl);
 357 }
 358
 359 /**
 360  * hsi_async_read - Submit a read transfer
 361  * @cl: Pointer to the HSI client
 362  * @msg: HSI message descriptor of the transfer
 363  *
 364  * Return -errno on failure, 0 on success
 365  */
 366 static inline int hsi_async_read(struct hsi_client *cl, struct hsi_msg *msg)
 367 {
 368         msg->ttype = HSI_MSG_READ;
 369         return hsi_async(cl, msg);
 370 }
 371
 372 /**
 373  * hsi_async_write - Submit a write transfer
 374  * @cl: Pointer to the HSI client
 375  * @msg: HSI message descriptor of the transfer
 376  *
 377  * Return -errno on failure, 0 on success
 378  */
 379 static inline int hsi_async_write(struct hsi_client *cl, struct hsi_msg *msg)
 380 {
 381         msg->ttype = HSI_MSG_WRITE;
 382         return hsi_async(cl, msg);
 383 }
 384
 385 /**
 386  * hsi_start_tx - Signal the port that the client wants to start a TX
 387  * @cl: Pointer to the HSI client
 388  *
 389  * Return -errno on failure, 0 on success
 390  */
 391 static inline int hsi_start_tx(struct hsi_client *cl)
 392 {
 393         if (!hsi_port_claimed(cl))
 394                 return -EACCES;
 395         return hsi_get_port(cl)->start_tx(cl);
 396 }
 397
 398 /**
 399  * hsi_stop_tx - Signal the port that the client no longer wants to transmit
 400  * @cl: Pointer to the HSI client
 401  *
 402  * Return -errno on failure, 0 on success
 403  */
 404 static inline int hsi_stop_tx(struct hsi_client *cl)
 405 {
 406         if (!hsi_port_claimed(cl))
 407                 return -EACCES;
 408         return hsi_get_port(cl)->stop_tx(cl);
 409 }
 410 #endif /* __LINUX_HSI_H__ */