1 /*
2 	Copyright (C) 2004 - 2010 Ivo van Doorn <IvDoorn@gmail.com>
3 	<http://rt2x00.serialmonkey.com>
4 
5 	This program is free software; you can redistribute it and/or modify
6 	it under the terms of the GNU General Public License as published by
7 	the Free Software Foundation; either version 2 of the License, or
8 	(at your option) any later version.
9 
10 	This program is distributed in the hope that it will be useful,
11 	but WITHOUT ANY WARRANTY; without even the implied warranty of
12 	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 	GNU General Public License for more details.
14 
15 	You should have received a copy of the GNU General Public License
16 	along with this program; if not, write to the
17 	Free Software Foundation, Inc.,
18 	59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19  */
20 
21 /*
22 	Module: rt2x00
23 	Abstract: rt2x00 queue datastructures and routines
24  */
25 
26 #ifndef RT2X00QUEUE_H
27 #define RT2X00QUEUE_H
28 
29 #include <linux/prefetch.h>
30 
31 /**
32  * DOC: Entry frame size
33  *
34  * Ralink PCI devices demand the Frame size to be a multiple of 128 bytes,
35  * for USB devices this restriction does not apply, but the value of
36  * 2432 makes sense since it is big enough to contain the maximum fragment
37  * size according to the ieee802.11 specs.
38  * The aggregation size depends on support from the driver, but should
39  * be something around 3840 bytes.
40  */
41 #define DATA_FRAME_SIZE		2432
42 #define MGMT_FRAME_SIZE		256
43 #define AGGREGATION_SIZE	3840
44 
45 /**
46  * enum data_queue_qid: Queue identification
47  *
48  * @QID_AC_VO: AC VO queue
49  * @QID_AC_VI: AC VI queue
50  * @QID_AC_BE: AC BE queue
51  * @QID_AC_BK: AC BK queue
52  * @QID_HCCA: HCCA queue
53  * @QID_MGMT: MGMT queue (prio queue)
54  * @QID_RX: RX queue
55  * @QID_OTHER: None of the above (don't use, only present for completeness)
56  * @QID_BEACON: Beacon queue (value unspecified, don't send it to device)
57  * @QID_ATIM: Atim queue (value unspeficied, don't send it to device)
58  */
59 enum data_queue_qid {
60 	QID_AC_VO = 0,
61 	QID_AC_VI = 1,
62 	QID_AC_BE = 2,
63 	QID_AC_BK = 3,
64 	QID_HCCA = 4,
65 	QID_MGMT = 13,
66 	QID_RX = 14,
67 	QID_OTHER = 15,
68 	QID_BEACON,
69 	QID_ATIM,
70 };
71 
72 /**
73  * enum skb_frame_desc_flags: Flags for &struct skb_frame_desc
74  *
75  * @SKBDESC_DMA_MAPPED_RX: &skb_dma field has been mapped for RX
76  * @SKBDESC_DMA_MAPPED_TX: &skb_dma field has been mapped for TX
77  * @SKBDESC_IV_STRIPPED: Frame contained a IV/EIV provided by
78  *	mac80211 but was stripped for processing by the driver.
79  * @SKBDESC_NOT_MAC80211: Frame didn't originate from mac80211,
80  *	don't try to pass it back.
81  * @SKBDESC_DESC_IN_SKB: The descriptor is at the start of the
82  *	skb, instead of in the desc field.
83  */
84 enum skb_frame_desc_flags {
85 	SKBDESC_DMA_MAPPED_RX = 1 << 0,
86 	SKBDESC_DMA_MAPPED_TX = 1 << 1,
87 	SKBDESC_IV_STRIPPED = 1 << 2,
88 	SKBDESC_NOT_MAC80211 = 1 << 3,
89 	SKBDESC_DESC_IN_SKB = 1 << 4,
90 };
91 
92 /**
93  * struct skb_frame_desc: Descriptor information for the skb buffer
94  *
95  * This structure is placed over the driver_data array, this means that
96  * this structure should not exceed the size of that array (40 bytes).
97  *
98  * @flags: Frame flags, see &enum skb_frame_desc_flags.
99  * @desc_len: Length of the frame descriptor.
100  * @tx_rate_idx: the index of the TX rate, used for TX status reporting
101  * @tx_rate_flags: the TX rate flags, used for TX status reporting
102  * @desc: Pointer to descriptor part of the frame.
103  *	Note that this pointer could point to something outside
104  *	of the scope of the skb->data pointer.
105  * @iv: IV/EIV data used during encryption/decryption.
106  * @skb_dma: (PCI-only) the DMA address associated with the sk buffer.
107  * @entry: The entry to which this sk buffer belongs.
108  */
109 struct skb_frame_desc {
110 	u8 flags;
111 
112 	u8 desc_len;
113 	u8 tx_rate_idx;
114 	u8 tx_rate_flags;
115 
116 	void *desc;
117 
118 	__le32 iv[2];
119 
120 	dma_addr_t skb_dma;
121 
122 	struct queue_entry *entry;
123 };
124 
125 /**
126  * get_skb_frame_desc - Obtain the rt2x00 frame descriptor from a sk_buff.
127  * @skb: &struct sk_buff from where we obtain the &struct skb_frame_desc
128  */
get_skb_frame_desc(struct sk_buff * skb)129 static inline struct skb_frame_desc* get_skb_frame_desc(struct sk_buff *skb)
130 {
131 	BUILD_BUG_ON(sizeof(struct skb_frame_desc) >
132 		     IEEE80211_TX_INFO_DRIVER_DATA_SIZE);
133 	return (struct skb_frame_desc *)&IEEE80211_SKB_CB(skb)->driver_data;
134 }
135 
136 /**
137  * enum rxdone_entry_desc_flags: Flags for &struct rxdone_entry_desc
138  *
139  * @RXDONE_SIGNAL_PLCP: Signal field contains the plcp value.
140  * @RXDONE_SIGNAL_BITRATE: Signal field contains the bitrate value.
141  * @RXDONE_SIGNAL_MCS: Signal field contains the mcs value.
142  * @RXDONE_MY_BSS: Does this frame originate from device's BSS.
143  * @RXDONE_CRYPTO_IV: Driver provided IV/EIV data.
144  * @RXDONE_CRYPTO_ICV: Driver provided ICV data.
145  * @RXDONE_L2PAD: 802.11 payload has been padded to 4-byte boundary.
146  */
147 enum rxdone_entry_desc_flags {
148 	RXDONE_SIGNAL_PLCP = BIT(0),
149 	RXDONE_SIGNAL_BITRATE = BIT(1),
150 	RXDONE_SIGNAL_MCS = BIT(2),
151 	RXDONE_MY_BSS = BIT(3),
152 	RXDONE_CRYPTO_IV = BIT(4),
153 	RXDONE_CRYPTO_ICV = BIT(5),
154 	RXDONE_L2PAD = BIT(6),
155 };
156 
157 /**
158  * RXDONE_SIGNAL_MASK - Define to mask off all &rxdone_entry_desc_flags flags
159  * except for the RXDONE_SIGNAL_* flags. This is useful to convert the dev_flags
160  * from &rxdone_entry_desc to a signal value type.
161  */
162 #define RXDONE_SIGNAL_MASK \
163 	( RXDONE_SIGNAL_PLCP | RXDONE_SIGNAL_BITRATE | RXDONE_SIGNAL_MCS )
164 
165 /**
166  * struct rxdone_entry_desc: RX Entry descriptor
167  *
168  * Summary of information that has been read from the RX frame descriptor.
169  *
170  * @timestamp: RX Timestamp
171  * @signal: Signal of the received frame.
172  * @rssi: RSSI of the received frame.
173  * @size: Data size of the received frame.
174  * @flags: MAC80211 receive flags (See &enum mac80211_rx_flags).
175  * @dev_flags: Ralink receive flags (See &enum rxdone_entry_desc_flags).
176  * @rate_mode: Rate mode (See @enum rate_modulation).
177  * @cipher: Cipher type used during decryption.
178  * @cipher_status: Decryption status.
179  * @iv: IV/EIV data used during decryption.
180  * @icv: ICV data used during decryption.
181  */
182 struct rxdone_entry_desc {
183 	u64 timestamp;
184 	int signal;
185 	int rssi;
186 	int size;
187 	int flags;
188 	int dev_flags;
189 	u16 rate_mode;
190 	u8 cipher;
191 	u8 cipher_status;
192 
193 	__le32 iv[2];
194 	__le32 icv;
195 };
196 
197 /**
198  * enum txdone_entry_desc_flags: Flags for &struct txdone_entry_desc
199  *
200  * Every txdone report has to contain the basic result of the
201  * transmission, either &TXDONE_UNKNOWN, &TXDONE_SUCCESS or
202  * &TXDONE_FAILURE. The flag &TXDONE_FALLBACK can be used in
203  * conjunction with all of these flags but should only be set
204  * if retires > 0. The flag &TXDONE_EXCESSIVE_RETRY can only be used
205  * in conjunction with &TXDONE_FAILURE.
206  *
207  * @TXDONE_UNKNOWN: Hardware could not determine success of transmission.
208  * @TXDONE_SUCCESS: Frame was successfully send
209  * @TXDONE_FALLBACK: Hardware used fallback rates for retries
210  * @TXDONE_FAILURE: Frame was not successfully send
211  * @TXDONE_EXCESSIVE_RETRY: In addition to &TXDONE_FAILURE, the
212  *	frame transmission failed due to excessive retries.
213  */
214 enum txdone_entry_desc_flags {
215 	TXDONE_UNKNOWN,
216 	TXDONE_SUCCESS,
217 	TXDONE_FALLBACK,
218 	TXDONE_FAILURE,
219 	TXDONE_EXCESSIVE_RETRY,
220 };
221 
222 /**
223  * struct txdone_entry_desc: TX done entry descriptor
224  *
225  * Summary of information that has been read from the TX frame descriptor
226  * after the device is done with transmission.
227  *
228  * @flags: TX done flags (See &enum txdone_entry_desc_flags).
229  * @retry: Retry count.
230  */
231 struct txdone_entry_desc {
232 	unsigned long flags;
233 	int retry;
234 };
235 
236 /**
237  * enum txentry_desc_flags: Status flags for TX entry descriptor
238  *
239  * @ENTRY_TXD_RTS_FRAME: This frame is a RTS frame.
240  * @ENTRY_TXD_CTS_FRAME: This frame is a CTS-to-self frame.
241  * @ENTRY_TXD_GENERATE_SEQ: This frame requires sequence counter.
242  * @ENTRY_TXD_FIRST_FRAGMENT: This is the first frame.
243  * @ENTRY_TXD_MORE_FRAG: This frame is followed by another fragment.
244  * @ENTRY_TXD_REQ_TIMESTAMP: Require timestamp to be inserted.
245  * @ENTRY_TXD_BURST: This frame belongs to the same burst event.
246  * @ENTRY_TXD_ACK: An ACK is required for this frame.
247  * @ENTRY_TXD_RETRY_MODE: When set, the long retry count is used.
248  * @ENTRY_TXD_ENCRYPT: This frame should be encrypted.
249  * @ENTRY_TXD_ENCRYPT_PAIRWISE: Use pairwise key table (instead of shared).
250  * @ENTRY_TXD_ENCRYPT_IV: Generate IV/EIV in hardware.
251  * @ENTRY_TXD_ENCRYPT_MMIC: Generate MIC in hardware.
252  * @ENTRY_TXD_HT_AMPDU: This frame is part of an AMPDU.
253  * @ENTRY_TXD_HT_BW_40: Use 40MHz Bandwidth.
254  * @ENTRY_TXD_HT_SHORT_GI: Use short GI.
255  * @ENTRY_TXD_HT_MIMO_PS: The receiving STA is in dynamic SM PS mode.
256  */
257 enum txentry_desc_flags {
258 	ENTRY_TXD_RTS_FRAME,
259 	ENTRY_TXD_CTS_FRAME,
260 	ENTRY_TXD_GENERATE_SEQ,
261 	ENTRY_TXD_FIRST_FRAGMENT,
262 	ENTRY_TXD_MORE_FRAG,
263 	ENTRY_TXD_REQ_TIMESTAMP,
264 	ENTRY_TXD_BURST,
265 	ENTRY_TXD_ACK,
266 	ENTRY_TXD_RETRY_MODE,
267 	ENTRY_TXD_ENCRYPT,
268 	ENTRY_TXD_ENCRYPT_PAIRWISE,
269 	ENTRY_TXD_ENCRYPT_IV,
270 	ENTRY_TXD_ENCRYPT_MMIC,
271 	ENTRY_TXD_HT_AMPDU,
272 	ENTRY_TXD_HT_BW_40,
273 	ENTRY_TXD_HT_SHORT_GI,
274 	ENTRY_TXD_HT_MIMO_PS,
275 };
276 
277 /**
278  * struct txentry_desc: TX Entry descriptor
279  *
280  * Summary of information for the frame descriptor before sending a TX frame.
281  *
282  * @flags: Descriptor flags (See &enum queue_entry_flags).
283  * @length: Length of the entire frame.
284  * @header_length: Length of 802.11 header.
285  * @length_high: PLCP length high word.
286  * @length_low: PLCP length low word.
287  * @signal: PLCP signal.
288  * @service: PLCP service.
289  * @msc: MCS.
290  * @stbc: STBC.
291  * @ba_size: BA size.
292  * @rate_mode: Rate mode (See @enum rate_modulation).
293  * @mpdu_density: MDPU density.
294  * @retry_limit: Max number of retries.
295  * @ifs: IFS value.
296  * @txop: IFS value for 11n capable chips.
297  * @cipher: Cipher type used for encryption.
298  * @key_idx: Key index used for encryption.
299  * @iv_offset: Position where IV should be inserted by hardware.
300  * @iv_len: Length of IV data.
301  */
302 struct txentry_desc {
303 	unsigned long flags;
304 
305 	u16 length;
306 	u16 header_length;
307 
308 	union {
309 		struct {
310 			u16 length_high;
311 			u16 length_low;
312 			u16 signal;
313 			u16 service;
314 			enum ifs ifs;
315 		} plcp;
316 
317 		struct {
318 			u16 mcs;
319 			u8 stbc;
320 			u8 ba_size;
321 			u8 mpdu_density;
322 			enum txop txop;
323 		} ht;
324 	} u;
325 
326 	enum rate_modulation rate_mode;
327 
328 	short retry_limit;
329 
330 	enum cipher cipher;
331 	u16 key_idx;
332 	u16 iv_offset;
333 	u16 iv_len;
334 };
335 
336 /**
337  * enum queue_entry_flags: Status flags for queue entry
338  *
339  * @ENTRY_BCN_ASSIGNED: This entry has been assigned to an interface.
340  *	As long as this bit is set, this entry may only be touched
341  *	through the interface structure.
342  * @ENTRY_OWNER_DEVICE_DATA: This entry is owned by the device for data
343  *	transfer (either TX or RX depending on the queue). The entry should
344  *	only be touched after the device has signaled it is done with it.
345  * @ENTRY_DATA_PENDING: This entry contains a valid frame and is waiting
346  *	for the signal to start sending.
347  * @ENTRY_DATA_IO_FAILED: Hardware indicated that an IO error occurred
348  *	while transferring the data to the hardware. No TX status report will
349  *	be expected from the hardware.
350  * @ENTRY_DATA_STATUS_PENDING: The entry has been send to the device and
351  *	returned. It is now waiting for the status reporting before the
352  *	entry can be reused again.
353  */
354 enum queue_entry_flags {
355 	ENTRY_BCN_ASSIGNED,
356 	ENTRY_OWNER_DEVICE_DATA,
357 	ENTRY_DATA_PENDING,
358 	ENTRY_DATA_IO_FAILED,
359 	ENTRY_DATA_STATUS_PENDING,
360 };
361 
362 /**
363  * struct queue_entry: Entry inside the &struct data_queue
364  *
365  * @flags: Entry flags, see &enum queue_entry_flags.
366  * @queue: The data queue (&struct data_queue) to which this entry belongs.
367  * @skb: The buffer which is currently being transmitted (for TX queue),
368  *	or used to directly receive data in (for RX queue).
369  * @entry_idx: The entry index number.
370  * @priv_data: Private data belonging to this queue entry. The pointer
371  *	points to data specific to a particular driver and queue type.
372  */
373 struct queue_entry {
374 	unsigned long flags;
375 
376 	struct data_queue *queue;
377 
378 	struct sk_buff *skb;
379 
380 	unsigned int entry_idx;
381 
382 	void *priv_data;
383 };
384 
385 /**
386  * enum queue_index: Queue index type
387  *
388  * @Q_INDEX: Index pointer to the current entry in the queue, if this entry is
389  *	owned by the hardware then the queue is considered to be full.
390  * @Q_INDEX_DMA_DONE: Index pointer for the next entry which will have been
391  *	transferred to the hardware.
392  * @Q_INDEX_DONE: Index pointer to the next entry which will be completed by
393  *	the hardware and for which we need to run the txdone handler. If this
394  *	entry is not owned by the hardware the queue is considered to be empty.
395  * @Q_INDEX_MAX: Keep last, used in &struct data_queue to determine the size
396  *	of the index array.
397  */
398 enum queue_index {
399 	Q_INDEX,
400 	Q_INDEX_DMA_DONE,
401 	Q_INDEX_DONE,
402 	Q_INDEX_MAX,
403 };
404 
405 /**
406  * enum data_queue_flags: Status flags for data queues
407  *
408  * @QUEUE_STARTED: The queue has been started. Fox RX queues this means the
409  *	device might be DMA'ing skbuffers. TX queues will accept skbuffers to
410  *	be transmitted and beacon queues will start beaconing the configured
411  *	beacons.
412  * @QUEUE_PAUSED: The queue has been started but is currently paused.
413  *	When this bit is set, the queue has been stopped in mac80211,
414  *	preventing new frames to be enqueued. However, a few frames
415  *	might still appear shortly after the pausing...
416  */
417 enum data_queue_flags {
418 	QUEUE_STARTED,
419 	QUEUE_PAUSED,
420 };
421 
422 /**
423  * struct data_queue: Data queue
424  *
425  * @rt2x00dev: Pointer to main &struct rt2x00dev where this queue belongs to.
426  * @entries: Base address of the &struct queue_entry which are
427  *	part of this queue.
428  * @qid: The queue identification, see &enum data_queue_qid.
429  * @flags: Entry flags, see &enum queue_entry_flags.
430  * @status_lock: The mutex for protecting the start/stop/flush
431  *	handling on this queue.
432  * @index_lock: Spinlock to protect index handling. Whenever @index, @index_done or
433  *	@index_crypt needs to be changed this lock should be grabbed to prevent
434  *	index corruption due to concurrency.
435  * @count: Number of frames handled in the queue.
436  * @limit: Maximum number of entries in the queue.
437  * @threshold: Minimum number of free entries before queue is kicked by force.
438  * @length: Number of frames in queue.
439  * @index: Index pointers to entry positions in the queue,
440  *	use &enum queue_index to get a specific index field.
441  * @txop: maximum burst time.
442  * @aifs: The aifs value for outgoing frames (field ignored in RX queue).
443  * @cw_min: The cw min value for outgoing frames (field ignored in RX queue).
444  * @cw_max: The cw max value for outgoing frames (field ignored in RX queue).
445  * @data_size: Maximum data size for the frames in this queue.
446  * @desc_size: Hardware descriptor size for the data in this queue.
447  * @usb_endpoint: Device endpoint used for communication (USB only)
448  * @usb_maxpacket: Max packet size for given endpoint (USB only)
449  */
450 struct data_queue {
451 	struct rt2x00_dev *rt2x00dev;
452 	struct queue_entry *entries;
453 
454 	enum data_queue_qid qid;
455 	unsigned long flags;
456 
457 	struct mutex status_lock;
458 	spinlock_t index_lock;
459 
460 	unsigned int count;
461 	unsigned short limit;
462 	unsigned short threshold;
463 	unsigned short length;
464 	unsigned short index[Q_INDEX_MAX];
465 	unsigned long last_action[Q_INDEX_MAX];
466 
467 	unsigned short txop;
468 	unsigned short aifs;
469 	unsigned short cw_min;
470 	unsigned short cw_max;
471 
472 	unsigned short data_size;
473 	unsigned short desc_size;
474 
475 	unsigned short usb_endpoint;
476 	unsigned short usb_maxpacket;
477 };
478 
479 /**
480  * struct data_queue_desc: Data queue description
481  *
482  * The information in this structure is used by drivers
483  * to inform rt2x00lib about the creation of the data queue.
484  *
485  * @entry_num: Maximum number of entries for a queue.
486  * @data_size: Maximum data size for the frames in this queue.
487  * @desc_size: Hardware descriptor size for the data in this queue.
488  * @priv_size: Size of per-queue_entry private data.
489  */
490 struct data_queue_desc {
491 	unsigned short entry_num;
492 	unsigned short data_size;
493 	unsigned short desc_size;
494 	unsigned short priv_size;
495 };
496 
497 /**
498  * queue_end - Return pointer to the last queue (HELPER MACRO).
499  * @__dev: Pointer to &struct rt2x00_dev
500  *
501  * Using the base rx pointer and the maximum number of available queues,
502  * this macro will return the address of 1 position beyond  the end of the
503  * queues array.
504  */
505 #define queue_end(__dev) \
506 	&(__dev)->rx[(__dev)->data_queues]
507 
508 /**
509  * tx_queue_end - Return pointer to the last TX queue (HELPER MACRO).
510  * @__dev: Pointer to &struct rt2x00_dev
511  *
512  * Using the base tx pointer and the maximum number of available TX
513  * queues, this macro will return the address of 1 position beyond
514  * the end of the TX queue array.
515  */
516 #define tx_queue_end(__dev) \
517 	&(__dev)->tx[(__dev)->ops->tx_queues]
518 
519 /**
520  * queue_next - Return pointer to next queue in list (HELPER MACRO).
521  * @__queue: Current queue for which we need the next queue
522  *
523  * Using the current queue address we take the address directly
524  * after the queue to take the next queue. Note that this macro
525  * should be used carefully since it does not protect against
526  * moving past the end of the list. (See macros &queue_end and
527  * &tx_queue_end for determining the end of the queue).
528  */
529 #define queue_next(__queue) \
530 	&(__queue)[1]
531 
532 /**
533  * queue_loop - Loop through the queues within a specific range (HELPER MACRO).
534  * @__entry: Pointer where the current queue entry will be stored in.
535  * @__start: Start queue pointer.
536  * @__end: End queue pointer.
537  *
538  * This macro will loop through all queues between &__start and &__end.
539  */
540 #define queue_loop(__entry, __start, __end)			\
541 	for ((__entry) = (__start);				\
542 	     prefetch(queue_next(__entry)), (__entry) != (__end);\
543 	     (__entry) = queue_next(__entry))
544 
545 /**
546  * queue_for_each - Loop through all queues
547  * @__dev: Pointer to &struct rt2x00_dev
548  * @__entry: Pointer where the current queue entry will be stored in.
549  *
550  * This macro will loop through all available queues.
551  */
552 #define queue_for_each(__dev, __entry) \
553 	queue_loop(__entry, (__dev)->rx, queue_end(__dev))
554 
555 /**
556  * tx_queue_for_each - Loop through the TX queues
557  * @__dev: Pointer to &struct rt2x00_dev
558  * @__entry: Pointer where the current queue entry will be stored in.
559  *
560  * This macro will loop through all TX related queues excluding
561  * the Beacon and Atim queues.
562  */
563 #define tx_queue_for_each(__dev, __entry) \
564 	queue_loop(__entry, (__dev)->tx, tx_queue_end(__dev))
565 
566 /**
567  * txall_queue_for_each - Loop through all TX related queues
568  * @__dev: Pointer to &struct rt2x00_dev
569  * @__entry: Pointer where the current queue entry will be stored in.
570  *
571  * This macro will loop through all TX related queues including
572  * the Beacon and Atim queues.
573  */
574 #define txall_queue_for_each(__dev, __entry) \
575 	queue_loop(__entry, (__dev)->tx, queue_end(__dev))
576 
577 /**
578  * rt2x00queue_for_each_entry - Loop through all entries in the queue
579  * @queue: Pointer to @data_queue
580  * @start: &enum queue_index Pointer to start index
581  * @end: &enum queue_index Pointer to end index
582  * @fn: The function to call for each &struct queue_entry
583  *
584  * This will walk through all entries in the queue, in chronological
585  * order. This means it will start at the current @start pointer
586  * and will walk through the queue until it reaches the @end pointer.
587  */
588 void rt2x00queue_for_each_entry(struct data_queue *queue,
589 				enum queue_index start,
590 				enum queue_index end,
591 				void (*fn)(struct queue_entry *entry));
592 
593 /**
594  * rt2x00queue_empty - Check if the queue is empty.
595  * @queue: Queue to check if empty.
596  */
rt2x00queue_empty(struct data_queue * queue)597 static inline int rt2x00queue_empty(struct data_queue *queue)
598 {
599 	return queue->length == 0;
600 }
601 
602 /**
603  * rt2x00queue_full - Check if the queue is full.
604  * @queue: Queue to check if full.
605  */
rt2x00queue_full(struct data_queue * queue)606 static inline int rt2x00queue_full(struct data_queue *queue)
607 {
608 	return queue->length == queue->limit;
609 }
610 
611 /**
612  * rt2x00queue_free - Check the number of available entries in queue.
613  * @queue: Queue to check.
614  */
rt2x00queue_available(struct data_queue * queue)615 static inline int rt2x00queue_available(struct data_queue *queue)
616 {
617 	return queue->limit - queue->length;
618 }
619 
620 /**
621  * rt2x00queue_threshold - Check if the queue is below threshold
622  * @queue: Queue to check.
623  */
rt2x00queue_threshold(struct data_queue * queue)624 static inline int rt2x00queue_threshold(struct data_queue *queue)
625 {
626 	return rt2x00queue_available(queue) < queue->threshold;
627 }
628 
629 /**
630  * rt2x00queue_status_timeout - Check if a timeout occurred for STATUS reports
631  * @queue: Queue to check.
632  */
rt2x00queue_status_timeout(struct data_queue * queue)633 static inline int rt2x00queue_status_timeout(struct data_queue *queue)
634 {
635 	return time_after(queue->last_action[Q_INDEX_DMA_DONE],
636 			  queue->last_action[Q_INDEX_DONE] + (HZ / 10));
637 }
638 
639 /**
640  * rt2x00queue_timeout - Check if a timeout occurred for DMA transfers
641  * @queue: Queue to check.
642  */
rt2x00queue_dma_timeout(struct data_queue * queue)643 static inline int rt2x00queue_dma_timeout(struct data_queue *queue)
644 {
645 	return time_after(queue->last_action[Q_INDEX],
646 			  queue->last_action[Q_INDEX_DMA_DONE] + (HZ / 10));
647 }
648 
649 /**
650  * _rt2x00_desc_read - Read a word from the hardware descriptor.
651  * @desc: Base descriptor address
652  * @word: Word index from where the descriptor should be read.
653  * @value: Address where the descriptor value should be written into.
654  */
_rt2x00_desc_read(__le32 * desc,const u8 word,__le32 * value)655 static inline void _rt2x00_desc_read(__le32 *desc, const u8 word, __le32 *value)
656 {
657 	*value = desc[word];
658 }
659 
660 /**
661  * rt2x00_desc_read - Read a word from the hardware descriptor, this
662  * function will take care of the byte ordering.
663  * @desc: Base descriptor address
664  * @word: Word index from where the descriptor should be read.
665  * @value: Address where the descriptor value should be written into.
666  */
rt2x00_desc_read(__le32 * desc,const u8 word,u32 * value)667 static inline void rt2x00_desc_read(__le32 *desc, const u8 word, u32 *value)
668 {
669 	__le32 tmp;
670 	_rt2x00_desc_read(desc, word, &tmp);
671 	*value = le32_to_cpu(tmp);
672 }
673 
674 /**
675  * rt2x00_desc_write - write a word to the hardware descriptor, this
676  * function will take care of the byte ordering.
677  * @desc: Base descriptor address
678  * @word: Word index from where the descriptor should be written.
679  * @value: Value that should be written into the descriptor.
680  */
_rt2x00_desc_write(__le32 * desc,const u8 word,__le32 value)681 static inline void _rt2x00_desc_write(__le32 *desc, const u8 word, __le32 value)
682 {
683 	desc[word] = value;
684 }
685 
686 /**
687  * rt2x00_desc_write - write a word to the hardware descriptor.
688  * @desc: Base descriptor address
689  * @word: Word index from where the descriptor should be written.
690  * @value: Value that should be written into the descriptor.
691  */
rt2x00_desc_write(__le32 * desc,const u8 word,u32 value)692 static inline void rt2x00_desc_write(__le32 *desc, const u8 word, u32 value)
693 {
694 	_rt2x00_desc_write(desc, word, cpu_to_le32(value));
695 }
696 
697 #endif /* RT2X00QUEUE_H */
698