include/linux/mhi.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
   4  *
   5  */
   6 #ifndef _MHI_H_
   7 #define _MHI_H_
   8
   9 #include <linux/device.h>
  10 #include <linux/dma-direction.h>
  11 #include <linux/mutex.h>
  12 #include <linux/rwlock_types.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/slab.h>
  15 #include <linux/spinlock_types.h>
  16 #include <linux/wait.h>
  17 #include <linux/workqueue.h>
  18
  19 struct mhi_chan;
  20 struct mhi_event;
  21 struct mhi_ctxt;
  22 struct mhi_cmd;
  23 struct mhi_buf_info;
  24
  25 /**
  26  * enum mhi_callback - MHI callback
  27  * @MHI_CB_IDLE: MHI entered idle state
  28  * @MHI_CB_PENDING_DATA: New data available for client to process
  29  * @MHI_CB_LPM_ENTER: MHI host entered low power mode
  30  * @MHI_CB_LPM_EXIT: MHI host about to exit low power mode
  31  * @MHI_CB_EE_RDDM: MHI device entered RDDM exec env
  32  * @MHI_CB_EE_MISSION_MODE: MHI device entered Mission Mode exec env
  33  * @MHI_CB_SYS_ERROR: MHI device entered error state (may recover)
  34  * @MHI_CB_FATAL_ERROR: MHI device entered fatal error state
  35  * @MHI_CB_BW_REQ: Received a bandwidth switch request from device
  36  */
  37 enum mhi_callback {
  38         MHI_CB_IDLE,
  39         MHI_CB_PENDING_DATA,
  40         MHI_CB_LPM_ENTER,
  41         MHI_CB_LPM_EXIT,
  42         MHI_CB_EE_RDDM,
  43         MHI_CB_EE_MISSION_MODE,
  44         MHI_CB_SYS_ERROR,
  45         MHI_CB_FATAL_ERROR,
  46         MHI_CB_BW_REQ,
  47 };
  48
  49 /**
  50  * enum mhi_flags - Transfer flags
  51  * @MHI_EOB: End of buffer for bulk transfer
  52  * @MHI_EOT: End of transfer
  53  * @MHI_CHAIN: Linked transfer
  54  */
  55 enum mhi_flags {
  56         MHI_EOB,
  57         MHI_EOT,
  58         MHI_CHAIN,
  59 };
  60
  61 /**
  62  * enum mhi_device_type - Device types
  63  * @MHI_DEVICE_XFER: Handles data transfer
  64  * @MHI_DEVICE_CONTROLLER: Control device
  65  */
  66 enum mhi_device_type {
  67         MHI_DEVICE_XFER,
  68         MHI_DEVICE_CONTROLLER,
  69 };
  70
  71 /**
  72  * enum mhi_ch_type - Channel types
  73  * @MHI_CH_TYPE_INVALID: Invalid channel type
  74  * @MHI_CH_TYPE_OUTBOUND: Outbound channel to the device
  75  * @MHI_CH_TYPE_INBOUND: Inbound channel from the device
  76  * @MHI_CH_TYPE_INBOUND_COALESCED: Coalesced channel for the device to combine
  77  *                                 multiple packets and send them as a single
  78  *                                 large packet to reduce CPU consumption
  79  */
  80 enum mhi_ch_type {
  81         MHI_CH_TYPE_INVALID = 0,
  82         MHI_CH_TYPE_OUTBOUND = DMA_TO_DEVICE,
  83         MHI_CH_TYPE_INBOUND = DMA_FROM_DEVICE,
  84         MHI_CH_TYPE_INBOUND_COALESCED = 3,
  85 };
  86
  87 /**
  88  * struct image_info - Firmware and RDDM table table
  89  * @mhi_buf - Buffer for firmware and RDDM table
  90  * @entries - # of entries in table
  91  */
  92 struct image_info {
  93         struct mhi_buf *mhi_buf;
  94         struct bhi_vec_entry *bhi_vec;
  95         u32 entries;
  96 };
  97
  98 /**
  99  * struct mhi_link_info - BW requirement
 100  * target_link_speed - Link speed as defined by TLS bits in LinkControl reg
 101  * target_link_width - Link width as defined by NLW bits in LinkStatus reg
 102  */
 103 struct mhi_link_info {
 104         unsigned int target_link_speed;
 105         unsigned int target_link_width;
 106 };
 107
 108 /**
 109  * enum mhi_ee_type - Execution environment types
 110  * @MHI_EE_PBL: Primary Bootloader
 111  * @MHI_EE_SBL: Secondary Bootloader
 112  * @MHI_EE_AMSS: Modem, aka the primary runtime EE
 113  * @MHI_EE_RDDM: Ram dump download mode
 114  * @MHI_EE_WFW: WLAN firmware mode
 115  * @MHI_EE_PTHRU: Passthrough
 116  * @MHI_EE_EDL: Embedded downloader
 117  */
 118 enum mhi_ee_type {
 119         MHI_EE_PBL,
 120         MHI_EE_SBL,
 121         MHI_EE_AMSS,
 122         MHI_EE_RDDM,
 123         MHI_EE_WFW,
 124         MHI_EE_PTHRU,
 125         MHI_EE_EDL,
 126         MHI_EE_MAX_SUPPORTED = MHI_EE_EDL,
 127         MHI_EE_DISABLE_TRANSITION, /* local EE, not related to mhi spec */
 128         MHI_EE_NOT_SUPPORTED,
 129         MHI_EE_MAX,
 130 };
 131
 132 /**
 133  * enum mhi_state - MHI states
 134  * @MHI_STATE_RESET: Reset state
 135  * @MHI_STATE_READY: Ready state
 136  * @MHI_STATE_M0: M0 state
 137  * @MHI_STATE_M1: M1 state
 138  * @MHI_STATE_M2: M2 state
 139  * @MHI_STATE_M3: M3 state
 140  * @MHI_STATE_M3_FAST: M3 Fast state
 141  * @MHI_STATE_BHI: BHI state
 142  * @MHI_STATE_SYS_ERR: System Error state
 143  */
 144 enum mhi_state {
 145         MHI_STATE_RESET = 0x0,
 146         MHI_STATE_READY = 0x1,
 147         MHI_STATE_M0 = 0x2,
 148         MHI_STATE_M1 = 0x3,
 149         MHI_STATE_M2 = 0x4,
 150         MHI_STATE_M3 = 0x5,
 151         MHI_STATE_M3_FAST = 0x6,
 152         MHI_STATE_BHI = 0x7,
 153         MHI_STATE_SYS_ERR = 0xFF,
 154         MHI_STATE_MAX,
 155 };
 156
 157 /**
 158  * enum mhi_ch_ee_mask - Execution environment mask for channel
 159  * @MHI_CH_EE_PBL: Allow channel to be used in PBL EE
 160  * @MHI_CH_EE_SBL: Allow channel to be used in SBL EE
 161  * @MHI_CH_EE_AMSS: Allow channel to be used in AMSS EE
 162  * @MHI_CH_EE_RDDM: Allow channel to be used in RDDM EE
 163  * @MHI_CH_EE_PTHRU: Allow channel to be used in PTHRU EE
 164  * @MHI_CH_EE_WFW: Allow channel to be used in WFW EE
 165  * @MHI_CH_EE_EDL: Allow channel to be used in EDL EE
 166  */
 167 enum mhi_ch_ee_mask {
 168         MHI_CH_EE_PBL = BIT(MHI_EE_PBL),
 169         MHI_CH_EE_SBL = BIT(MHI_EE_SBL),
 170         MHI_CH_EE_AMSS = BIT(MHI_EE_AMSS),
 171         MHI_CH_EE_RDDM = BIT(MHI_EE_RDDM),
 172         MHI_CH_EE_PTHRU = BIT(MHI_EE_PTHRU),
 173         MHI_CH_EE_WFW = BIT(MHI_EE_WFW),
 174         MHI_CH_EE_EDL = BIT(MHI_EE_EDL),
 175 };
 176
 177 /**
 178  * enum mhi_er_data_type - Event ring data types
 179  * @MHI_ER_DATA: Only client data over this ring
 180  * @MHI_ER_CTRL: MHI control data and client data
 181  */
 182 enum mhi_er_data_type {
 183         MHI_ER_DATA,
 184         MHI_ER_CTRL,
 185 };
 186
 187 /**
 188  * enum mhi_db_brst_mode - Doorbell mode
 189  * @MHI_DB_BRST_DISABLE: Burst mode disable
 190  * @MHI_DB_BRST_ENABLE: Burst mode enable
 191  */
 192 enum mhi_db_brst_mode {
 193         MHI_DB_BRST_DISABLE = 0x2,
 194         MHI_DB_BRST_ENABLE = 0x3,
 195 };
 196
 197 /**
 198  * struct mhi_channel_config - Channel configuration structure for controller
 199  * @name: The name of this channel
 200  * @num: The number assigned to this channel
 201  * @num_elements: The number of elements that can be queued to this channel
 202  * @local_elements: The local ring length of the channel
 203  * @event_ring: The event rung index that services this channel
 204  * @dir: Direction that data may flow on this channel
 205  * @type: Channel type
 206  * @ee_mask: Execution Environment mask for this channel
 207  * @pollcfg: Polling configuration for burst mode.  0 is default.  milliseconds
 208              for UL channels, multiple of 8 ring elements for DL channels
 209  * @doorbell: Doorbell mode
 210  * @lpm_notify: The channel master requires low power mode notifications
 211  * @offload_channel: The client manages the channel completely
 212  * @doorbell_mode_switch: Channel switches to doorbell mode on M0 transition
 213  * @auto_queue: Framework will automatically queue buffers for DL traffic
 214  * @auto_start: Automatically start (open) this channel
 215  * @wake-capable: Channel capable of waking up the system
 216  */
 217 struct mhi_channel_config {
 218         char *name;
 219         u32 num;
 220         u32 num_elements;
 221         u32 local_elements;
 222         u32 event_ring;
 223         enum dma_data_direction dir;
 224         enum mhi_ch_type type;
 225         u32 ee_mask;
 226         u32 pollcfg;
 227         enum mhi_db_brst_mode doorbell;
 228         bool lpm_notify;
 229         bool offload_channel;
 230         bool doorbell_mode_switch;
 231         bool auto_queue;
 232         bool auto_start;
 233         bool wake_capable;
 234 };
 235
 236 /**
 237  * struct mhi_event_config - Event ring configuration structure for controller
 238  * @num_elements: The number of elements that can be queued to this ring
 239  * @irq_moderation_ms: Delay irq for additional events to be aggregated
 240  * @irq: IRQ associated with this ring
 241  * @channel: Dedicated channel number. U32_MAX indicates a non-dedicated ring
 242  * @priority: Priority of this ring. Use 1 for now
 243  * @mode: Doorbell mode
 244  * @data_type: Type of data this ring will process
 245  * @hardware_event: This ring is associated with hardware channels
 246  * @client_managed: This ring is client managed
 247  * @offload_channel: This ring is associated with an offloaded channel
 248  */
 249 struct mhi_event_config {
 250         u32 num_elements;
 251         u32 irq_moderation_ms;
 252         u32 irq;
 253         u32 channel;
 254         u32 priority;
 255         enum mhi_db_brst_mode mode;
 256         enum mhi_er_data_type data_type;
 257         bool hardware_event;
 258         bool client_managed;
 259         bool offload_channel;
 260 };
 261
 262 /**
 263  * struct mhi_controller_config - Root MHI controller configuration
 264  * @max_channels: Maximum number of channels supported
 265  * @timeout_ms: Timeout value for operations. 0 means use default
 266  * @buf_len: Size of automatically allocated buffers. 0 means use default
 267  * @num_channels: Number of channels defined in @ch_cfg
 268  * @ch_cfg: Array of defined channels
 269  * @num_events: Number of event rings defined in @event_cfg
 270  * @event_cfg: Array of defined event rings
 271  * @use_bounce_buf: Use a bounce buffer pool due to limited DDR access
 272  * @m2_no_db: Host is not allowed to ring DB in M2 state
 273  */
 274 struct mhi_controller_config {
 275         u32 max_channels;
 276         u32 timeout_ms;
 277         u32 buf_len;
 278         u32 num_channels;
 279         struct mhi_channel_config *ch_cfg;
 280         u32 num_events;
 281         struct mhi_event_config *event_cfg;
 282         bool use_bounce_buf;
 283         bool m2_no_db;
 284 };
 285
 286 /**
 287  * struct mhi_controller - Master MHI controller structure
 288  * @cntrl_dev: Pointer to the struct device of physical bus acting as the MHI
 289  *            controller (required)
 290  * @mhi_dev: MHI device instance for the controller
 291  * @regs: Base address of MHI MMIO register space (required)
 292  * @bhi: Points to base of MHI BHI register space
 293  * @bhie: Points to base of MHI BHIe register space
 294  * @wake_db: MHI WAKE doorbell register address
 295  * @iova_start: IOMMU starting address for data (required)
 296  * @iova_stop: IOMMU stop address for data (required)
 297  * @fw_image: Firmware image name for normal booting (required)
 298  * @edl_image: Firmware image name for emergency download mode (optional)
 299  * @rddm_size: RAM dump size that host should allocate for debugging purpose
 300  * @sbl_size: SBL image size downloaded through BHIe (optional)
 301  * @seg_len: BHIe vector size (optional)
 302  * @fbc_image: Points to firmware image buffer
 303  * @rddm_image: Points to RAM dump buffer
 304  * @mhi_chan: Points to the channel configuration table
 305  * @lpm_chans: List of channels that require LPM notifications
 306  * @irq: base irq # to request (required)
 307  * @max_chan: Maximum number of channels the controller supports
 308  * @total_ev_rings: Total # of event rings allocated
 309  * @hw_ev_rings: Number of hardware event rings
 310  * @sw_ev_rings: Number of software event rings
 311  * @nr_irqs_req: Number of IRQs required to operate (optional)
 312  * @nr_irqs: Number of IRQ allocated by bus master (required)
 313  * @family_number: MHI controller family number
 314  * @device_number: MHI controller device number
 315  * @major_version: MHI controller major revision number
 316  * @minor_version: MHI controller minor revision number
 317  * @mhi_event: MHI event ring configurations table
 318  * @mhi_cmd: MHI command ring configurations table
 319  * @mhi_ctxt: MHI device context, shared memory between host and device
 320  * @pm_mutex: Mutex for suspend/resume operation
 321  * @pm_lock: Lock for protecting MHI power management state
 322  * @timeout_ms: Timeout in ms for state transitions
 323  * @pm_state: MHI power management state
 324  * @db_access: DB access states
 325  * @ee: MHI device execution environment
 326  * @dev_state: MHI device state
 327  * @dev_wake: Device wakeup count
 328  * @pending_pkts: Pending packets for the controller
 329  * @transition_list: List of MHI state transitions
 330  * @transition_lock: Lock for protecting MHI state transition list
 331  * @wlock: Lock for protecting device wakeup
 332  * @mhi_link_info: Device bandwidth info
 333  * @st_worker: State transition worker
 334  * @fw_worker: Firmware download worker
 335  * @syserr_worker: System error worker
 336  * @state_event: State change event
 337  * @status_cb: CB function to notify power states of the device (required)
 338  * @link_status: CB function to query link status of the device (required)
 339  * @wake_get: CB function to assert device wake (optional)
 340  * @wake_put: CB function to de-assert device wake (optional)
 341  * @wake_toggle: CB function to assert and de-assert device wake (optional)
 342  * @runtime_get: CB function to controller runtime resume (required)
 343  * @runtimet_put: CB function to decrement pm usage (required)
 344  * @map_single: CB function to create TRE buffer
 345  * @unmap_single: CB function to destroy TRE buffer
 346  * @buffer_len: Bounce buffer length
 347  * @bounce_buf: Use of bounce buffer
 348  * @fbc_download: MHI host needs to do complete image transfer (optional)
 349  * @pre_init: MHI host needs to do pre-initialization before power up
 350  * @wake_set: Device wakeup set flag
 351  *
 352  * Fields marked as (required) need to be populated by the controller driver
 353  * before calling mhi_register_controller(). For the fields marked as (optional)
 354  * they can be populated depending on the usecase.
 355  *
 356  * The following fields are present for the purpose of implementing any device
 357  * specific quirks or customizations for specific MHI revisions used in device
 358  * by the controller drivers. The MHI stack will just populate these fields
 359  * during mhi_register_controller():
 360  *  family_number
 361  *  device_number
 362  *  major_version
 363  *  minor_version
 364  */
 365 struct mhi_controller {
 366         struct device *cntrl_dev;
 367         struct mhi_device *mhi_dev;
 368         void __iomem *regs;
 369         void __iomem *bhi;
 370         void __iomem *bhie;
 371         void __iomem *wake_db;
 372
 373         dma_addr_t iova_start;
 374         dma_addr_t iova_stop;
 375         const char *fw_image;
 376         const char *edl_image;
 377         size_t rddm_size;
 378         size_t sbl_size;
 379         size_t seg_len;
 380         struct image_info *fbc_image;
 381         struct image_info *rddm_image;
 382         struct mhi_chan *mhi_chan;
 383         struct list_head lpm_chans;
 384         int *irq;
 385         u32 max_chan;
 386         u32 total_ev_rings;
 387         u32 hw_ev_rings;
 388         u32 sw_ev_rings;
 389         u32 nr_irqs_req;
 390         u32 nr_irqs;
 391         u32 family_number;
 392         u32 device_number;
 393         u32 major_version;
 394         u32 minor_version;
 395
 396         struct mhi_event *mhi_event;
 397         struct mhi_cmd *mhi_cmd;
 398         struct mhi_ctxt *mhi_ctxt;
 399
 400         struct mutex pm_mutex;
 401         rwlock_t pm_lock;
 402         u32 timeout_ms;
 403         u32 pm_state;
 404         u32 db_access;
 405         enum mhi_ee_type ee;
 406         enum mhi_state dev_state;
 407         atomic_t dev_wake;
 408         atomic_t pending_pkts;
 409         struct list_head transition_list;
 410         spinlock_t transition_lock;
 411         spinlock_t wlock;
 412         struct mhi_link_info mhi_link_info;
 413         struct work_struct st_worker;
 414         struct work_struct fw_worker;
 415         struct work_struct syserr_worker;
 416         wait_queue_head_t state_event;
 417
 418         void (*status_cb)(struct mhi_controller *mhi_cntrl,
 419                           enum mhi_callback cb);
 420         int (*link_status)(struct mhi_controller *mhi_cntrl);
 421         void (*wake_get)(struct mhi_controller *mhi_cntrl, bool override);
 422         void (*wake_put)(struct mhi_controller *mhi_cntrl, bool override);
 423         void (*wake_toggle)(struct mhi_controller *mhi_cntrl);
 424         int (*runtime_get)(struct mhi_controller *mhi_cntrl);
 425         void (*runtime_put)(struct mhi_controller *mhi_cntrl);
 426         int (*map_single)(struct mhi_controller *mhi_cntrl,
 427                           struct mhi_buf_info *buf);
 428         void (*unmap_single)(struct mhi_controller *mhi_cntrl,
 429                              struct mhi_buf_info *buf);
 430
 431         size_t buffer_len;
 432         bool bounce_buf;
 433         bool fbc_download;
 434         bool pre_init;
 435         bool wake_set;
 436 };
 437
 438 /**
 439  * struct mhi_device - Structure representing a MHI device which binds
 440  *                     to channels
 441  * @id: Pointer to MHI device ID struct
 442  * @chan_name: Name of the channel to which the device binds
 443  * @mhi_cntrl: Controller the device belongs to
 444  * @ul_chan: UL channel for the device
 445  * @dl_chan: DL channel for the device
 446  * @dev: Driver model device node for the MHI device
 447  * @dev_type: MHI device type
 448  * @ul_chan_id: MHI channel id for UL transfer
 449  * @dl_chan_id: MHI channel id for DL transfer
 450  * @dev_wake: Device wakeup counter
 451  */
 452 struct mhi_device {
 453         const struct mhi_device_id *id;
 454         const char *chan_name;
 455         struct mhi_controller *mhi_cntrl;
 456         struct mhi_chan *ul_chan;
 457         struct mhi_chan *dl_chan;
 458         struct device dev;
 459         enum mhi_device_type dev_type;
 460         int ul_chan_id;
 461         int dl_chan_id;
 462         u32 dev_wake;
 463 };
 464
 465 /**
 466  * struct mhi_result - Completed buffer information
 467  * @buf_addr: Address of data buffer
 468  * @bytes_xferd: # of bytes transferred
 469  * @dir: Channel direction
 470  * @transaction_status: Status of last transaction
 471  */
 472 struct mhi_result {
 473         void *buf_addr;
 474         size_t bytes_xferd;
 475         enum dma_data_direction dir;
 476         int transaction_status;
 477 };
 478
 479 /**
 480  * struct mhi_buf - MHI Buffer description
 481  * @buf: Virtual address of the buffer
 482  * @name: Buffer label. For offload channel, configurations name must be:
 483  *        ECA - Event context array data
 484  *        CCA - Channel context array data
 485  * @dma_addr: IOMMU address of the buffer
 486  * @len: # of bytes
 487  */
 488 struct mhi_buf {
 489         void *buf;
 490         const char *name;
 491         dma_addr_t dma_addr;
 492         size_t len;
 493 };
 494
 495 /**
 496  * struct mhi_driver - Structure representing a MHI client driver
 497  * @probe: CB function for client driver probe function
 498  * @remove: CB function for client driver remove function
 499  * @ul_xfer_cb: CB function for UL data transfer
 500  * @dl_xfer_cb: CB function for DL data transfer
 501  * @status_cb: CB functions for asynchronous status
 502  * @driver: Device driver model driver
 503  */
 504 struct mhi_driver {
 505         const struct mhi_device_id *id_table;
 506         int (*probe)(struct mhi_device *mhi_dev,
 507                      const struct mhi_device_id *id);
 508         void (*remove)(struct mhi_device *mhi_dev);
 509         void (*ul_xfer_cb)(struct mhi_device *mhi_dev,
 510                            struct mhi_result *result);
 511         void (*dl_xfer_cb)(struct mhi_device *mhi_dev,
 512                            struct mhi_result *result);
 513         void (*status_cb)(struct mhi_device *mhi_dev, enum mhi_callback mhi_cb);
 514         struct device_driver driver;
 515 };
 516
 517 #define to_mhi_driver(drv) container_of(drv, struct mhi_driver, driver)
 518 #define to_mhi_device(dev) container_of(dev, struct mhi_device, dev)
 519
 520 /**
 521  * mhi_register_controller - Register MHI controller
 522  * @mhi_cntrl: MHI controller to register
 523  * @config: Configuration to use for the controller
 524  */
 525 int mhi_register_controller(struct mhi_controller *mhi_cntrl,
 526                             struct mhi_controller_config *config);
 527
 528 /**
 529  * mhi_unregister_controller - Unregister MHI controller
 530  * @mhi_cntrl: MHI controller to unregister
 531  */
 532 void mhi_unregister_controller(struct mhi_controller *mhi_cntrl);
 533
 534 /*
 535  * module_mhi_driver() - Helper macro for drivers that don't do
 536  * anything special other than using default mhi_driver_register() and
 537  * mhi_driver_unregister().  This eliminates a lot of boilerplate.
 538  * Each module may only use this macro once.
 539  */
 540 #define module_mhi_driver(mhi_drv) \
 541         module_driver(mhi_drv, mhi_driver_register, \
 542                       mhi_driver_unregister)
 543
 544 /*
 545  * Macro to avoid include chaining to get THIS_MODULE
 546  */
 547 #define mhi_driver_register(mhi_drv) \
 548         __mhi_driver_register(mhi_drv, THIS_MODULE)
 549
 550 /**
 551  * __mhi_driver_register - Register driver with MHI framework
 552  * @mhi_drv: Driver associated with the device
 553  * @owner: The module owner
 554  */
 555 int __mhi_driver_register(struct mhi_driver *mhi_drv, struct module *owner);
 556
 557 /**
 558  * mhi_driver_unregister - Unregister a driver for mhi_devices
 559  * @mhi_drv: Driver associated with the device
 560  */
 561 void mhi_driver_unregister(struct mhi_driver *mhi_drv);
 562
 563 /**
 564  * mhi_set_mhi_state - Set MHI device state
 565  * @mhi_cntrl: MHI controller
 566  * @state: State to set
 567  */
 568 void mhi_set_mhi_state(struct mhi_controller *mhi_cntrl,
 569                        enum mhi_state state);
 570
 571 /**
 572  * mhi_prepare_for_power_up - Do pre-initialization before power up.
 573  *                            This is optional, call this before power up if
 574  *                            the controller does not want bus framework to
 575  *                            automatically free any allocated memory during
 576  *                            shutdown process.
 577  * @mhi_cntrl: MHI controller
 578  */
 579 int mhi_prepare_for_power_up(struct mhi_controller *mhi_cntrl);
 580
 581 /**
 582  * mhi_async_power_up - Start MHI power up sequence
 583  * @mhi_cntrl: MHI controller
 584  */
 585 int mhi_async_power_up(struct mhi_controller *mhi_cntrl);
 586
 587 /**
 588  * mhi_sync_power_up - Start MHI power up sequence and wait till the device
 589  *                     device enters valid EE state
 590  * @mhi_cntrl: MHI controller
 591  */
 592 int mhi_sync_power_up(struct mhi_controller *mhi_cntrl);
 593
 594 /**
 595  * mhi_power_down - Start MHI power down sequence
 596  * @mhi_cntrl: MHI controller
 597  * @graceful: Link is still accessible, so do a graceful shutdown process
 598  */
 599 void mhi_power_down(struct mhi_controller *mhi_cntrl, bool graceful);
 600
 601 /**
 602  * mhi_unprepare_after_power_down - Free any allocated memory after power down
 603  * @mhi_cntrl: MHI controller
 604  */
 605 void mhi_unprepare_after_power_down(struct mhi_controller *mhi_cntrl);
 606
 607 /**
 608  * mhi_download_rddm_img - Download ramdump image from device for
 609  *                         debugging purpose.
 610  * @mhi_cntrl: MHI controller
 611  * @in_panic: Download rddm image during kernel panic
 612  */
 613 int mhi_download_rddm_img(struct mhi_controller *mhi_cntrl, bool in_panic);
 614
 615 /**
 616  * mhi_force_rddm_mode - Force device into rddm mode
 617  * @mhi_cntrl: MHI controller
 618  */
 619 int mhi_force_rddm_mode(struct mhi_controller *mhi_cntrl);
 620
 621 /**
 622  * mhi_get_mhi_state - Get MHI state of the device
 623  * @mhi_cntrl: MHI controller
 624  */
 625 enum mhi_state mhi_get_mhi_state(struct mhi_controller *mhi_cntrl);
 626
 627 /**
 628  * mhi_device_get - Disable device low power mode
 629  * @mhi_dev: Device associated with the channel
 630  */
 631 void mhi_device_get(struct mhi_device *mhi_dev);
 632
 633 /**
 634  * mhi_device_get_sync - Disable device low power mode. Synchronously
 635  *                       take the controller out of suspended state
 636  * @mhi_dev: Device associated with the channel
 637  */
 638 int mhi_device_get_sync(struct mhi_device *mhi_dev);
 639
 640 /**
 641  * mhi_device_put - Re-enable device low power mode
 642  * @mhi_dev: Device associated with the channel
 643  */
 644 void mhi_device_put(struct mhi_device *mhi_dev);
 645
 646 /**
 647  * mhi_prepare_for_transfer - Setup channel for data transfer
 648  * @mhi_dev: Device associated with the channels
 649  */
 650 int mhi_prepare_for_transfer(struct mhi_device *mhi_dev);
 651
 652 /**
 653  * mhi_unprepare_from_transfer - Unprepare the channels
 654  * @mhi_dev: Device associated with the channels
 655  */
 656 void mhi_unprepare_from_transfer(struct mhi_device *mhi_dev);
 657
 658 /**
 659  * mhi_poll - Poll for any available data in DL direction
 660  * @mhi_dev: Device associated with the channels
 661  * @budget: # of events to process
 662  */
 663 int mhi_poll(struct mhi_device *mhi_dev, u32 budget);
 664
 665 /**
 666  * mhi_queue_dma - Send or receive DMA mapped buffers from client device
 667  *                 over MHI channel
 668  * @mhi_dev: Device associated with the channels
 669  * @dir: DMA direction for the channel
 670  * @mhi_buf: Buffer for holding the DMA mapped data
 671  * @len: Buffer length
 672  * @mflags: MHI transfer flags used for the transfer
 673  */
 674 int mhi_queue_dma(struct mhi_device *mhi_dev, enum dma_data_direction dir,
 675                   struct mhi_buf *mhi_buf, size_t len, enum mhi_flags mflags);
 676
 677 /**
 678  * mhi_queue_buf - Send or receive raw buffers from client device over MHI
 679  *                 channel
 680  * @mhi_dev: Device associated with the channels
 681  * @dir: DMA direction for the channel
 682  * @buf: Buffer for holding the data
 683  * @len: Buffer length
 684  * @mflags: MHI transfer flags used for the transfer
 685  */
 686 int mhi_queue_buf(struct mhi_device *mhi_dev, enum dma_data_direction dir,
 687                   void *buf, size_t len, enum mhi_flags mflags);
 688
 689 /**
 690  * mhi_queue_skb - Send or receive SKBs from client device over MHI channel
 691  * @mhi_dev: Device associated with the channels
 692  * @dir: DMA direction for the channel
 693  * @skb: Buffer for holding SKBs
 694  * @len: Buffer length
 695  * @mflags: MHI transfer flags used for the transfer
 696  */
 697 int mhi_queue_skb(struct mhi_device *mhi_dev, enum dma_data_direction dir,
 698                   struct sk_buff *skb, size_t len, enum mhi_flags mflags);
 699
 700 #endif /* _MHI_H_ */