1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved.
9 #include <linux/device.h>
10 #include <linux/dma-direction.h>
11 #include <linux/mutex.h>
12 #include <linux/skbuff.h>
13 #include <linux/slab.h>
14 #include <linux/spinlock.h>
15 #include <linux/wait.h>
16 #include <linux/workqueue.h>
18 #define MHI_MAX_OEM_PK_HASH_SEGMENTS 16
27 * enum mhi_callback - MHI callback
28 * @MHI_CB_IDLE: MHI entered idle state
29 * @MHI_CB_PENDING_DATA: New data available for client to process
30 * @MHI_CB_LPM_ENTER: MHI host entered low power mode
31 * @MHI_CB_LPM_EXIT: MHI host about to exit low power mode
32 * @MHI_CB_EE_RDDM: MHI device entered RDDM exec env
33 * @MHI_CB_EE_MISSION_MODE: MHI device entered Mission Mode exec env
34 * @MHI_CB_SYS_ERROR: MHI device entered error state (may recover)
35 * @MHI_CB_FATAL_ERROR: MHI device entered fatal error state
36 * @MHI_CB_BW_REQ: Received a bandwidth switch request from device
44 MHI_CB_EE_MISSION_MODE
,
51 * enum mhi_flags - Transfer flags
52 * @MHI_EOB: End of buffer for bulk transfer
53 * @MHI_EOT: End of transfer
54 * @MHI_CHAIN: Linked transfer
63 * enum mhi_device_type - Device types
64 * @MHI_DEVICE_XFER: Handles data transfer
65 * @MHI_DEVICE_CONTROLLER: Control device
67 enum mhi_device_type
{
69 MHI_DEVICE_CONTROLLER
,
73 * enum mhi_ch_type - Channel types
74 * @MHI_CH_TYPE_INVALID: Invalid channel type
75 * @MHI_CH_TYPE_OUTBOUND: Outbound channel to the device
76 * @MHI_CH_TYPE_INBOUND: Inbound channel from the device
77 * @MHI_CH_TYPE_INBOUND_COALESCED: Coalesced channel for the device to combine
78 * multiple packets and send them as a single
79 * large packet to reduce CPU consumption
82 MHI_CH_TYPE_INVALID
= 0,
83 MHI_CH_TYPE_OUTBOUND
= DMA_TO_DEVICE
,
84 MHI_CH_TYPE_INBOUND
= DMA_FROM_DEVICE
,
85 MHI_CH_TYPE_INBOUND_COALESCED
= 3,
89 * struct image_info - Firmware and RDDM table
90 * @mhi_buf: Buffer for firmware and RDDM table
91 * @entries: # of entries in table
94 struct mhi_buf
*mhi_buf
;
95 /* private: from internal.h */
96 struct bhi_vec_entry
*bhi_vec
;
102 * struct mhi_link_info - BW requirement
103 * target_link_speed - Link speed as defined by TLS bits in LinkControl reg
104 * target_link_width - Link width as defined by NLW bits in LinkStatus reg
106 struct mhi_link_info
{
107 unsigned int target_link_speed
;
108 unsigned int target_link_width
;
112 * enum mhi_ee_type - Execution environment types
113 * @MHI_EE_PBL: Primary Bootloader
114 * @MHI_EE_SBL: Secondary Bootloader
115 * @MHI_EE_AMSS: Modem, aka the primary runtime EE
116 * @MHI_EE_RDDM: Ram dump download mode
117 * @MHI_EE_WFW: WLAN firmware mode
118 * @MHI_EE_PTHRU: Passthrough
119 * @MHI_EE_EDL: Embedded downloader
129 MHI_EE_MAX_SUPPORTED
= MHI_EE_EDL
,
130 MHI_EE_DISABLE_TRANSITION
, /* local EE, not related to mhi spec */
131 MHI_EE_NOT_SUPPORTED
,
136 * enum mhi_state - MHI states
137 * @MHI_STATE_RESET: Reset state
138 * @MHI_STATE_READY: Ready state
139 * @MHI_STATE_M0: M0 state
140 * @MHI_STATE_M1: M1 state
141 * @MHI_STATE_M2: M2 state
142 * @MHI_STATE_M3: M3 state
143 * @MHI_STATE_M3_FAST: M3 Fast state
144 * @MHI_STATE_BHI: BHI state
145 * @MHI_STATE_SYS_ERR: System Error state
148 MHI_STATE_RESET
= 0x0,
149 MHI_STATE_READY
= 0x1,
154 MHI_STATE_M3_FAST
= 0x6,
156 MHI_STATE_SYS_ERR
= 0xFF,
161 * enum mhi_ch_ee_mask - Execution environment mask for channel
162 * @MHI_CH_EE_PBL: Allow channel to be used in PBL EE
163 * @MHI_CH_EE_SBL: Allow channel to be used in SBL EE
164 * @MHI_CH_EE_AMSS: Allow channel to be used in AMSS EE
165 * @MHI_CH_EE_RDDM: Allow channel to be used in RDDM EE
166 * @MHI_CH_EE_PTHRU: Allow channel to be used in PTHRU EE
167 * @MHI_CH_EE_WFW: Allow channel to be used in WFW EE
168 * @MHI_CH_EE_EDL: Allow channel to be used in EDL EE
170 enum mhi_ch_ee_mask
{
171 MHI_CH_EE_PBL
= BIT(MHI_EE_PBL
),
172 MHI_CH_EE_SBL
= BIT(MHI_EE_SBL
),
173 MHI_CH_EE_AMSS
= BIT(MHI_EE_AMSS
),
174 MHI_CH_EE_RDDM
= BIT(MHI_EE_RDDM
),
175 MHI_CH_EE_PTHRU
= BIT(MHI_EE_PTHRU
),
176 MHI_CH_EE_WFW
= BIT(MHI_EE_WFW
),
177 MHI_CH_EE_EDL
= BIT(MHI_EE_EDL
),
181 * enum mhi_er_data_type - Event ring data types
182 * @MHI_ER_DATA: Only client data over this ring
183 * @MHI_ER_CTRL: MHI control data and client data
185 enum mhi_er_data_type
{
191 * enum mhi_db_brst_mode - Doorbell mode
192 * @MHI_DB_BRST_DISABLE: Burst mode disable
193 * @MHI_DB_BRST_ENABLE: Burst mode enable
195 enum mhi_db_brst_mode
{
196 MHI_DB_BRST_DISABLE
= 0x2,
197 MHI_DB_BRST_ENABLE
= 0x3,
201 * struct mhi_channel_config - Channel configuration structure for controller
202 * @name: The name of this channel
203 * @num: The number assigned to this channel
204 * @num_elements: The number of elements that can be queued to this channel
205 * @local_elements: The local ring length of the channel
206 * @event_ring: The event rung index that services this channel
207 * @dir: Direction that data may flow on this channel
208 * @type: Channel type
209 * @ee_mask: Execution Environment mask for this channel
210 * @pollcfg: Polling configuration for burst mode. 0 is default. milliseconds
211 for UL channels, multiple of 8 ring elements for DL channels
212 * @doorbell: Doorbell mode
213 * @lpm_notify: The channel master requires low power mode notifications
214 * @offload_channel: The client manages the channel completely
215 * @doorbell_mode_switch: Channel switches to doorbell mode on M0 transition
216 * @auto_queue: Framework will automatically queue buffers for DL traffic
217 * @wake-capable: Channel capable of waking up the system
219 struct mhi_channel_config
{
225 enum dma_data_direction dir
;
226 enum mhi_ch_type type
;
229 enum mhi_db_brst_mode doorbell
;
231 bool offload_channel
;
232 bool doorbell_mode_switch
;
238 * struct mhi_event_config - Event ring configuration structure for controller
239 * @num_elements: The number of elements that can be queued to this ring
240 * @irq_moderation_ms: Delay irq for additional events to be aggregated
241 * @irq: IRQ associated with this ring
242 * @channel: Dedicated channel number. U32_MAX indicates a non-dedicated ring
243 * @priority: Priority of this ring. Use 1 for now
244 * @mode: Doorbell mode
245 * @data_type: Type of data this ring will process
246 * @hardware_event: This ring is associated with hardware channels
247 * @client_managed: This ring is client managed
248 * @offload_channel: This ring is associated with an offloaded channel
250 struct mhi_event_config
{
252 u32 irq_moderation_ms
;
256 enum mhi_db_brst_mode mode
;
257 enum mhi_er_data_type data_type
;
260 bool offload_channel
;
264 * struct mhi_controller_config - Root MHI controller configuration
265 * @max_channels: Maximum number of channels supported
266 * @timeout_ms: Timeout value for operations. 0 means use default
267 * @buf_len: Size of automatically allocated buffers. 0 means use default
268 * @num_channels: Number of channels defined in @ch_cfg
269 * @ch_cfg: Array of defined channels
270 * @num_events: Number of event rings defined in @event_cfg
271 * @event_cfg: Array of defined event rings
272 * @use_bounce_buf: Use a bounce buffer pool due to limited DDR access
273 * @m2_no_db: Host is not allowed to ring DB in M2 state
275 struct mhi_controller_config
{
280 const struct mhi_channel_config
*ch_cfg
;
282 const struct mhi_event_config
*event_cfg
;
288 * struct mhi_controller - Master MHI controller structure
289 * @cntrl_dev: Pointer to the struct device of physical bus acting as the MHI
290 * controller (required)
291 * @mhi_dev: MHI device instance for the controller
292 * @debugfs_dentry: MHI controller debugfs directory
293 * @regs: Base address of MHI MMIO register space (required)
294 * @bhi: Points to base of MHI BHI register space
295 * @bhie: Points to base of MHI BHIe register space
296 * @wake_db: MHI WAKE doorbell register address
297 * @iova_start: IOMMU starting address for data (required)
298 * @iova_stop: IOMMU stop address for data (required)
299 * @fw_image: Firmware image name for normal booting (required)
300 * @edl_image: Firmware image name for emergency download mode (optional)
301 * @rddm_size: RAM dump size that host should allocate for debugging purpose
302 * @sbl_size: SBL image size downloaded through BHIe (optional)
303 * @seg_len: BHIe vector size (optional)
304 * @fbc_image: Points to firmware image buffer
305 * @rddm_image: Points to RAM dump buffer
306 * @mhi_chan: Points to the channel configuration table
307 * @lpm_chans: List of channels that require LPM notifications
308 * @irq: base irq # to request (required)
309 * @max_chan: Maximum number of channels the controller supports
310 * @total_ev_rings: Total # of event rings allocated
311 * @hw_ev_rings: Number of hardware event rings
312 * @sw_ev_rings: Number of software event rings
313 * @nr_irqs: Number of IRQ allocated by bus master (required)
314 * @family_number: MHI controller family number
315 * @device_number: MHI controller device number
316 * @major_version: MHI controller major revision number
317 * @minor_version: MHI controller minor revision number
318 * @serial_number: MHI controller serial number obtained from BHI
319 * @oem_pk_hash: MHI controller OEM PK Hash obtained from BHI
320 * @mhi_event: MHI event ring configurations table
321 * @mhi_cmd: MHI command ring configurations table
322 * @mhi_ctxt: MHI device context, shared memory between host and device
323 * @pm_mutex: Mutex for suspend/resume operation
324 * @pm_lock: Lock for protecting MHI power management state
325 * @timeout_ms: Timeout in ms for state transitions
326 * @pm_state: MHI power management state
327 * @db_access: DB access states
328 * @ee: MHI device execution environment
329 * @dev_state: MHI device state
330 * @dev_wake: Device wakeup count
331 * @pending_pkts: Pending packets for the controller
332 * @M0, M2, M3: Counters to track number of device MHI state changes
333 * @transition_list: List of MHI state transitions
334 * @transition_lock: Lock for protecting MHI state transition list
335 * @wlock: Lock for protecting device wakeup
336 * @mhi_link_info: Device bandwidth info
337 * @st_worker: State transition worker
338 * @hiprio_wq: High priority workqueue for MHI work such as state transitions
339 * @state_event: State change event
340 * @status_cb: CB function to notify power states of the device (required)
341 * @wake_get: CB function to assert device wake (optional)
342 * @wake_put: CB function to de-assert device wake (optional)
343 * @wake_toggle: CB function to assert and de-assert device wake (optional)
344 * @runtime_get: CB function to controller runtime resume (required)
345 * @runtime_put: CB function to decrement pm usage (required)
346 * @map_single: CB function to create TRE buffer
347 * @unmap_single: CB function to destroy TRE buffer
348 * @read_reg: Read a MHI register via the physical link (required)
349 * @write_reg: Write a MHI register via the physical link (required)
350 * @buffer_len: Bounce buffer length
351 * @index: Index of the MHI controller instance
352 * @bounce_buf: Use of bounce buffer
353 * @fbc_download: MHI host needs to do complete image transfer (optional)
354 * @pre_init: MHI host needs to do pre-initialization before power up
355 * @wake_set: Device wakeup set flag
357 * Fields marked as (required) need to be populated by the controller driver
358 * before calling mhi_register_controller(). For the fields marked as (optional)
359 * they can be populated depending on the usecase.
361 * The following fields are present for the purpose of implementing any device
362 * specific quirks or customizations for specific MHI revisions used in device
363 * by the controller drivers. The MHI stack will just populate these fields
364 * during mhi_register_controller():
370 struct mhi_controller
{
371 struct device
*cntrl_dev
;
372 struct mhi_device
*mhi_dev
;
373 struct dentry
*debugfs_dentry
;
377 void __iomem
*wake_db
;
379 dma_addr_t iova_start
;
380 dma_addr_t iova_stop
;
381 const char *fw_image
;
382 const char *edl_image
;
386 struct image_info
*fbc_image
;
387 struct image_info
*rddm_image
;
388 struct mhi_chan
*mhi_chan
;
389 struct list_head lpm_chans
;
401 u32 oem_pk_hash
[MHI_MAX_OEM_PK_HASH_SEGMENTS
];
403 struct mhi_event
*mhi_event
;
404 struct mhi_cmd
*mhi_cmd
;
405 struct mhi_ctxt
*mhi_ctxt
;
407 struct mutex pm_mutex
;
413 enum mhi_state dev_state
;
415 atomic_t pending_pkts
;
417 struct list_head transition_list
;
418 spinlock_t transition_lock
;
420 struct mhi_link_info mhi_link_info
;
421 struct work_struct st_worker
;
422 struct workqueue_struct
*hiprio_wq
;
423 wait_queue_head_t state_event
;
425 void (*status_cb
)(struct mhi_controller
*mhi_cntrl
,
426 enum mhi_callback cb
);
427 void (*wake_get
)(struct mhi_controller
*mhi_cntrl
, bool override
);
428 void (*wake_put
)(struct mhi_controller
*mhi_cntrl
, bool override
);
429 void (*wake_toggle
)(struct mhi_controller
*mhi_cntrl
);
430 int (*runtime_get
)(struct mhi_controller
*mhi_cntrl
);
431 void (*runtime_put
)(struct mhi_controller
*mhi_cntrl
);
432 int (*map_single
)(struct mhi_controller
*mhi_cntrl
,
433 struct mhi_buf_info
*buf
);
434 void (*unmap_single
)(struct mhi_controller
*mhi_cntrl
,
435 struct mhi_buf_info
*buf
);
436 int (*read_reg
)(struct mhi_controller
*mhi_cntrl
, void __iomem
*addr
,
438 void (*write_reg
)(struct mhi_controller
*mhi_cntrl
, void __iomem
*addr
,
450 * struct mhi_device - Structure representing an MHI device which binds
451 * to channels or is associated with controllers
452 * @id: Pointer to MHI device ID struct
453 * @name: Name of the associated MHI device
454 * @mhi_cntrl: Controller the device belongs to
455 * @ul_chan: UL channel for the device
456 * @dl_chan: DL channel for the device
457 * @dev: Driver model device node for the MHI device
458 * @dev_type: MHI device type
459 * @ul_chan_id: MHI channel id for UL transfer
460 * @dl_chan_id: MHI channel id for DL transfer
461 * @dev_wake: Device wakeup counter
464 const struct mhi_device_id
*id
;
466 struct mhi_controller
*mhi_cntrl
;
467 struct mhi_chan
*ul_chan
;
468 struct mhi_chan
*dl_chan
;
470 enum mhi_device_type dev_type
;
477 * struct mhi_result - Completed buffer information
478 * @buf_addr: Address of data buffer
479 * @bytes_xferd: # of bytes transferred
480 * @dir: Channel direction
481 * @transaction_status: Status of last transaction
486 enum dma_data_direction dir
;
487 int transaction_status
;
491 * struct mhi_buf - MHI Buffer description
492 * @buf: Virtual address of the buffer
493 * @name: Buffer label. For offload channel, configurations name must be:
494 * ECA - Event context array data
495 * CCA - Channel context array data
496 * @dma_addr: IOMMU address of the buffer
507 * struct mhi_driver - Structure representing a MHI client driver
508 * @probe: CB function for client driver probe function
509 * @remove: CB function for client driver remove function
510 * @ul_xfer_cb: CB function for UL data transfer
511 * @dl_xfer_cb: CB function for DL data transfer
512 * @status_cb: CB functions for asynchronous status
513 * @driver: Device driver model driver
516 const struct mhi_device_id
*id_table
;
517 int (*probe
)(struct mhi_device
*mhi_dev
,
518 const struct mhi_device_id
*id
);
519 void (*remove
)(struct mhi_device
*mhi_dev
);
520 void (*ul_xfer_cb
)(struct mhi_device
*mhi_dev
,
521 struct mhi_result
*result
);
522 void (*dl_xfer_cb
)(struct mhi_device
*mhi_dev
,
523 struct mhi_result
*result
);
524 void (*status_cb
)(struct mhi_device
*mhi_dev
, enum mhi_callback mhi_cb
);
525 struct device_driver driver
;
528 #define to_mhi_driver(drv) container_of(drv, struct mhi_driver, driver)
529 #define to_mhi_device(dev) container_of(dev, struct mhi_device, dev)
532 * mhi_alloc_controller - Allocate the MHI Controller structure
533 * Allocate the mhi_controller structure using zero initialized memory
535 struct mhi_controller
*mhi_alloc_controller(void);
538 * mhi_free_controller - Free the MHI Controller structure
539 * Free the mhi_controller structure which was previously allocated
541 void mhi_free_controller(struct mhi_controller
*mhi_cntrl
);
544 * mhi_register_controller - Register MHI controller
545 * @mhi_cntrl: MHI controller to register
546 * @config: Configuration to use for the controller
548 int mhi_register_controller(struct mhi_controller
*mhi_cntrl
,
549 const struct mhi_controller_config
*config
);
552 * mhi_unregister_controller - Unregister MHI controller
553 * @mhi_cntrl: MHI controller to unregister
555 void mhi_unregister_controller(struct mhi_controller
*mhi_cntrl
);
558 * module_mhi_driver() - Helper macro for drivers that don't do
559 * anything special other than using default mhi_driver_register() and
560 * mhi_driver_unregister(). This eliminates a lot of boilerplate.
561 * Each module may only use this macro once.
563 #define module_mhi_driver(mhi_drv) \
564 module_driver(mhi_drv, mhi_driver_register, \
565 mhi_driver_unregister)
568 * Macro to avoid include chaining to get THIS_MODULE
570 #define mhi_driver_register(mhi_drv) \
571 __mhi_driver_register(mhi_drv, THIS_MODULE)
574 * __mhi_driver_register - Register driver with MHI framework
575 * @mhi_drv: Driver associated with the device
576 * @owner: The module owner
578 int __mhi_driver_register(struct mhi_driver
*mhi_drv
, struct module
*owner
);
581 * mhi_driver_unregister - Unregister a driver for mhi_devices
582 * @mhi_drv: Driver associated with the device
584 void mhi_driver_unregister(struct mhi_driver
*mhi_drv
);
587 * mhi_set_mhi_state - Set MHI device state
588 * @mhi_cntrl: MHI controller
589 * @state: State to set
591 void mhi_set_mhi_state(struct mhi_controller
*mhi_cntrl
,
592 enum mhi_state state
);
595 * mhi_notify - Notify the MHI client driver about client device status
596 * @mhi_dev: MHI device instance
597 * @cb_reason: MHI callback reason
599 void mhi_notify(struct mhi_device
*mhi_dev
, enum mhi_callback cb_reason
);
602 * mhi_prepare_for_power_up - Do pre-initialization before power up.
603 * This is optional, call this before power up if
604 * the controller does not want bus framework to
605 * automatically free any allocated memory during
607 * @mhi_cntrl: MHI controller
609 int mhi_prepare_for_power_up(struct mhi_controller
*mhi_cntrl
);
612 * mhi_async_power_up - Start MHI power up sequence
613 * @mhi_cntrl: MHI controller
615 int mhi_async_power_up(struct mhi_controller
*mhi_cntrl
);
618 * mhi_sync_power_up - Start MHI power up sequence and wait till the device
619 * enters valid EE state
620 * @mhi_cntrl: MHI controller
622 int mhi_sync_power_up(struct mhi_controller
*mhi_cntrl
);
625 * mhi_power_down - Start MHI power down sequence
626 * @mhi_cntrl: MHI controller
627 * @graceful: Link is still accessible, so do a graceful shutdown process
629 void mhi_power_down(struct mhi_controller
*mhi_cntrl
, bool graceful
);
632 * mhi_unprepare_after_power_down - Free any allocated memory after power down
633 * @mhi_cntrl: MHI controller
635 void mhi_unprepare_after_power_down(struct mhi_controller
*mhi_cntrl
);
638 * mhi_pm_suspend - Move MHI into a suspended state
639 * @mhi_cntrl: MHI controller
641 int mhi_pm_suspend(struct mhi_controller
*mhi_cntrl
);
644 * mhi_pm_resume - Resume MHI from suspended state
645 * @mhi_cntrl: MHI controller
647 int mhi_pm_resume(struct mhi_controller
*mhi_cntrl
);
650 * mhi_download_rddm_image - Download ramdump image from device for
652 * @mhi_cntrl: MHI controller
653 * @in_panic: Download rddm image during kernel panic
655 int mhi_download_rddm_image(struct mhi_controller
*mhi_cntrl
, bool in_panic
);
658 * mhi_force_rddm_mode - Force device into rddm mode
659 * @mhi_cntrl: MHI controller
661 int mhi_force_rddm_mode(struct mhi_controller
*mhi_cntrl
);
664 * mhi_get_exec_env - Get BHI execution environment of the device
665 * @mhi_cntrl: MHI controller
667 enum mhi_ee_type
mhi_get_exec_env(struct mhi_controller
*mhi_cntrl
);
670 * mhi_get_mhi_state - Get MHI state of the device
671 * @mhi_cntrl: MHI controller
673 enum mhi_state
mhi_get_mhi_state(struct mhi_controller
*mhi_cntrl
);
676 * mhi_device_get - Disable device low power mode
677 * @mhi_dev: Device associated with the channel
679 void mhi_device_get(struct mhi_device
*mhi_dev
);
682 * mhi_device_get_sync - Disable device low power mode. Synchronously
683 * take the controller out of suspended state
684 * @mhi_dev: Device associated with the channel
686 int mhi_device_get_sync(struct mhi_device
*mhi_dev
);
689 * mhi_device_put - Re-enable device low power mode
690 * @mhi_dev: Device associated with the channel
692 void mhi_device_put(struct mhi_device
*mhi_dev
);
695 * mhi_prepare_for_transfer - Setup channel for data transfer
696 * @mhi_dev: Device associated with the channels
698 int mhi_prepare_for_transfer(struct mhi_device
*mhi_dev
);
701 * mhi_unprepare_from_transfer - Unprepare the channels
702 * @mhi_dev: Device associated with the channels
704 void mhi_unprepare_from_transfer(struct mhi_device
*mhi_dev
);
707 * mhi_poll - Poll for any available data in DL direction
708 * @mhi_dev: Device associated with the channels
709 * @budget: # of events to process
711 int mhi_poll(struct mhi_device
*mhi_dev
, u32 budget
);
714 * mhi_queue_dma - Send or receive DMA mapped buffers from client device
716 * @mhi_dev: Device associated with the channels
717 * @dir: DMA direction for the channel
718 * @mhi_buf: Buffer for holding the DMA mapped data
719 * @len: Buffer length
720 * @mflags: MHI transfer flags used for the transfer
722 int mhi_queue_dma(struct mhi_device
*mhi_dev
, enum dma_data_direction dir
,
723 struct mhi_buf
*mhi_buf
, size_t len
, enum mhi_flags mflags
);
726 * mhi_queue_buf - Send or receive raw buffers from client device over MHI
728 * @mhi_dev: Device associated with the channels
729 * @dir: DMA direction for the channel
730 * @buf: Buffer for holding the data
731 * @len: Buffer length
732 * @mflags: MHI transfer flags used for the transfer
734 int mhi_queue_buf(struct mhi_device
*mhi_dev
, enum dma_data_direction dir
,
735 void *buf
, size_t len
, enum mhi_flags mflags
);
738 * mhi_queue_skb - Send or receive SKBs from client device over MHI channel
739 * @mhi_dev: Device associated with the channels
740 * @dir: DMA direction for the channel
741 * @skb: Buffer for holding SKBs
742 * @len: Buffer length
743 * @mflags: MHI transfer flags used for the transfer
745 int mhi_queue_skb(struct mhi_device
*mhi_dev
, enum dma_data_direction dir
,
746 struct sk_buff
*skb
, size_t len
, enum mhi_flags mflags
);
749 * mhi_queue_is_full - Determine whether queueing new elements is possible
750 * @mhi_dev: Device associated with the channels
751 * @dir: DMA direction for the channel
753 bool mhi_queue_is_full(struct mhi_device
*mhi_dev
, enum dma_data_direction dir
);