summaryrefslogtreecommitdiffstats
path: root/drivers/tty/serial/msm_serial_hs.c
blob: c356ffff3c711a9f53cca21983840e1f621c13f3 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
/*
 * MSM 7k/8k High speed uart driver
 *
 * Copyright (c) 2007-2011, Code Aurora Forum. All rights reserved.
 * Copyright (c) 2008 Google Inc.
 * Modified: Nick Pelly <npelly@google.com>
 *
 * 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.
 *
 * Has optional support for uart power management independent of linux
 * suspend/resume:
 *
 * RX wakeup.
 * UART wakeup can be triggered by RX activity (using a wakeup GPIO on the
 * UART RX pin). This should only be used if there is not a wakeup
 * GPIO on the UART CTS, and the first RX byte is known (for example, with the
 * Bluetooth Texas Instruments HCILL protocol), since the first RX byte will
 * always be lost. RTS will be asserted even while the UART is off in this mode
 * of operation. See msm_serial_hs_platform_data.rx_wakeup_irq.
 */

#include <linux/module.h>

#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/timer.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/dma-mapping.h>
#include <linux/dmapool.h>
#include <linux/wait.h>
#include <linux/workqueue.h>

#include <linux/atomic.h>
#include <asm/irq.h>

#include <mach/hardware.h>
#include <mach/dma.h>
#include <linux/platform_data/msm_serial_hs.h>

/* HSUART Registers */
#define UARTDM_MR1_ADDR 0x0
#define UARTDM_MR2_ADDR 0x4

/* Data Mover result codes */
#define RSLT_FIFO_CNTR_BMSK (0xE << 28)
#define RSLT_VLD            BIT(1)

/* write only register */
#define UARTDM_CSR_ADDR 0x8
#define UARTDM_CSR_115200 0xFF
#define UARTDM_CSR_57600  0xEE
#define UARTDM_CSR_38400  0xDD
#define UARTDM_CSR_28800  0xCC
#define UARTDM_CSR_19200  0xBB
#define UARTDM_CSR_14400  0xAA
#define UARTDM_CSR_9600   0x99
#define UARTDM_CSR_7200   0x88
#define UARTDM_CSR_4800   0x77
#define UARTDM_CSR_3600   0x66
#define UARTDM_CSR_2400   0x55
#define UARTDM_CSR_1200   0x44
#define UARTDM_CSR_600    0x33
#define UARTDM_CSR_300    0x22
#define UARTDM_CSR_150    0x11
#define UARTDM_CSR_75     0x00

/* write only register */
#define UARTDM_TF_ADDR 0x70
#define UARTDM_TF2_ADDR 0x74
#define UARTDM_TF3_ADDR 0x78
#define UARTDM_TF4_ADDR 0x7C

/* write only register */
#define UARTDM_CR_ADDR 0x10
#define UARTDM_IMR_ADDR 0x14

#define UARTDM_IPR_ADDR 0x18
#define UARTDM_TFWR_ADDR 0x1c
#define UARTDM_RFWR_ADDR 0x20
#define UARTDM_HCR_ADDR 0x24
#define UARTDM_DMRX_ADDR 0x34
#define UARTDM_IRDA_ADDR 0x38
#define UARTDM_DMEN_ADDR 0x3c

/* UART_DM_NO_CHARS_FOR_TX */
#define UARTDM_NCF_TX_ADDR 0x40

#define UARTDM_BADR_ADDR 0x44

#define UARTDM_SIM_CFG_ADDR 0x80
/* Read Only register */
#define UARTDM_SR_ADDR 0x8

/* Read Only register */
#define UARTDM_RF_ADDR  0x70
#define UARTDM_RF2_ADDR 0x74
#define UARTDM_RF3_ADDR 0x78
#define UARTDM_RF4_ADDR 0x7C

/* Read Only register */
#define UARTDM_MISR_ADDR 0x10

/* Read Only register */
#define UARTDM_ISR_ADDR 0x14
#define UARTDM_RX_TOTAL_SNAP_ADDR 0x38

#define UARTDM_RXFS_ADDR 0x50

/* Register field Mask Mapping */
#define UARTDM_SR_PAR_FRAME_BMSK        BIT(5)
#define UARTDM_SR_OVERRUN_BMSK          BIT(4)
#define UARTDM_SR_TXEMT_BMSK            BIT(3)
#define UARTDM_SR_TXRDY_BMSK            BIT(2)
#define UARTDM_SR_RXRDY_BMSK            BIT(0)

#define UARTDM_CR_TX_DISABLE_BMSK       BIT(3)
#define UARTDM_CR_RX_DISABLE_BMSK       BIT(1)
#define UARTDM_CR_TX_EN_BMSK            BIT(2)
#define UARTDM_CR_RX_EN_BMSK            BIT(0)

/* UARTDM_CR channel_comman bit value (register field is bits 8:4) */
#define RESET_RX                0x10
#define RESET_TX                0x20
#define RESET_ERROR_STATUS      0x30
#define RESET_BREAK_INT         0x40
#define START_BREAK             0x50
#define STOP_BREAK              0x60
#define RESET_CTS               0x70
#define RESET_STALE_INT         0x80
#define RFR_LOW                 0xD0
#define RFR_HIGH                0xE0
#define CR_PROTECTION_EN        0x100
#define STALE_EVENT_ENABLE      0x500
#define STALE_EVENT_DISABLE     0x600
#define FORCE_STALE_EVENT       0x400
#define CLEAR_TX_READY          0x300
#define RESET_TX_ERROR          0x800
#define RESET_TX_DONE           0x810

#define UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK 0xffffff00
#define UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK 0x3f
#define UARTDM_MR1_CTS_CTL_BMSK 0x40
#define UARTDM_MR1_RX_RDY_CTL_BMSK 0x80

#define UARTDM_MR2_ERROR_MODE_BMSK 0x40
#define UARTDM_MR2_BITS_PER_CHAR_BMSK 0x30

/* bits per character configuration */
#define FIVE_BPC  (0 << 4)
#define SIX_BPC   (1 << 4)
#define SEVEN_BPC (2 << 4)
#define EIGHT_BPC (3 << 4)

#define UARTDM_MR2_STOP_BIT_LEN_BMSK 0xc
#define STOP_BIT_ONE (1 << 2)
#define STOP_BIT_TWO (3 << 2)

#define UARTDM_MR2_PARITY_MODE_BMSK 0x3

/* Parity configuration */
#define NO_PARITY 0x0
#define EVEN_PARITY 0x1
#define ODD_PARITY 0x2
#define SPACE_PARITY 0x3

#define UARTDM_IPR_STALE_TIMEOUT_MSB_BMSK 0xffffff80
#define UARTDM_IPR_STALE_LSB_BMSK 0x1f

/* These can be used for both ISR and IMR register */
#define UARTDM_ISR_TX_READY_BMSK        BIT(7)
#define UARTDM_ISR_CURRENT_CTS_BMSK     BIT(6)
#define UARTDM_ISR_DELTA_CTS_BMSK       BIT(5)
#define UARTDM_ISR_RXLEV_BMSK           BIT(4)
#define UARTDM_ISR_RXSTALE_BMSK         BIT(3)
#define UARTDM_ISR_RXBREAK_BMSK         BIT(2)
#define UARTDM_ISR_RXHUNT_BMSK          BIT(1)
#define UARTDM_ISR_TXLEV_BMSK           BIT(0)

/* Field definitions for UART_DM_DMEN*/
#define UARTDM_TX_DM_EN_BMSK 0x1
#define UARTDM_RX_DM_EN_BMSK 0x2

#define UART_FIFOSIZE 64
#define UARTCLK 7372800

/* Rx DMA request states */
enum flush_reason {
	FLUSH_NONE,
	FLUSH_DATA_READY,
	FLUSH_DATA_INVALID,  /* values after this indicate invalid data */
	FLUSH_IGNORE = FLUSH_DATA_INVALID,
	FLUSH_STOP,
	FLUSH_SHUTDOWN,
};

/* UART clock states */
enum msm_hs_clk_states_e {
	MSM_HS_CLK_PORT_OFF,     /* port not in use */
	MSM_HS_CLK_OFF,          /* clock disabled */
	MSM_HS_CLK_REQUEST_OFF,  /* disable after TX and RX flushed */
	MSM_HS_CLK_ON,           /* clock enabled */
};

/* Track the forced RXSTALE flush during clock off sequence.
 * These states are only valid during MSM_HS_CLK_REQUEST_OFF */
enum msm_hs_clk_req_off_state_e {
	CLK_REQ_OFF_START,
	CLK_REQ_OFF_RXSTALE_ISSUED,
	CLK_REQ_OFF_FLUSH_ISSUED,
	CLK_REQ_OFF_RXSTALE_FLUSHED,
};

/**
 * struct msm_hs_tx
 * @tx_ready_int_en: ok to dma more tx?
 * @dma_in_flight: tx dma in progress
 * @xfer: top level DMA command pointer structure
 * @command_ptr: third level command struct pointer
 * @command_ptr_ptr: second level command list struct pointer
 * @mapped_cmd_ptr: DMA view of third level command struct
 * @mapped_cmd_ptr_ptr: DMA view of second level command list struct
 * @tx_count: number of bytes to transfer in DMA transfer
 * @dma_base: DMA view of UART xmit buffer
 *
 * This structure describes a single Tx DMA transaction. MSM DMA
 * commands have two levels of indirection. The top level command
 * ptr points to a list of command ptr which in turn points to a
 * single DMA 'command'. In our case each Tx transaction consists
 * of a single second level pointer pointing to a 'box type' command.
 */
struct msm_hs_tx {
	unsigned int tx_ready_int_en;
	unsigned int dma_in_flight;
	struct msm_dmov_cmd xfer;
	dmov_box *command_ptr;
	u32 *command_ptr_ptr;
	dma_addr_t mapped_cmd_ptr;
	dma_addr_t mapped_cmd_ptr_ptr;
	int tx_count;
	dma_addr_t dma_base;
};

/**
 * struct msm_hs_rx
 * @flush: Rx DMA request state
 * @xfer: top level DMA command pointer structure
 * @cmdptr_dmaaddr: DMA view of second level command structure
 * @command_ptr: third level DMA command pointer structure
 * @command_ptr_ptr: second level DMA command list pointer
 * @mapped_cmd_ptr: DMA view of the third level command structure
 * @wait: wait for DMA completion before shutdown
 * @buffer: destination buffer for RX DMA
 * @rbuffer: DMA view of buffer
 * @pool: dma pool out of which coherent rx buffer is allocated
 * @tty_work: private work-queue for tty flip buffer push task
 *
 * This structure describes a single Rx DMA transaction. Rx DMA
 * transactions use box mode DMA commands.
 */
struct msm_hs_rx {
	enum flush_reason flush;
	struct msm_dmov_cmd xfer;
	dma_addr_t cmdptr_dmaaddr;
	dmov_box *command_ptr;
	u32 *command_ptr_ptr;
	dma_addr_t mapped_cmd_ptr;
	wait_queue_head_t wait;
	dma_addr_t rbuffer;
	unsigned char *buffer;
	struct dma_pool *pool;
	struct work_struct tty_work;
};

/**
 * struct msm_hs_rx_wakeup
 * @irq: IRQ line to be configured as interrupt source on Rx activity
 * @ignore: boolean value. 1 = ignore the wakeup interrupt
 * @rx_to_inject: extra character to be inserted to Rx tty on wakeup
 * @inject_rx: 1 = insert rx_to_inject. 0 = do not insert extra character
 *
 * This is an optional structure required for UART Rx GPIO IRQ based
 * wakeup from low power state. UART wakeup can be triggered by RX activity
 * (using a wakeup GPIO on the UART RX pin). This should only be used if
 * there is not a wakeup GPIO on the UART CTS, and the first RX byte is
 * known (eg., with the Bluetooth Texas Instruments HCILL protocol),
 * since the first RX byte will always be lost. RTS will be asserted even
 * while the UART is clocked off in this mode of operation.
 */
struct msm_hs_rx_wakeup {
	int irq;  /* < 0 indicates low power wakeup disabled */
	unsigned char ignore;
	unsigned char inject_rx;
	char rx_to_inject;
};

/**
 * struct msm_hs_port
 * @uport: embedded uart port structure
 * @imr_reg: shadow value of UARTDM_IMR
 * @clk: uart input clock handle
 * @tx: Tx transaction related data structure
 * @rx: Rx transaction related data structure
 * @dma_tx_channel: Tx DMA command channel
 * @dma_rx_channel Rx DMA command channel
 * @dma_tx_crci: Tx channel rate control interface number
 * @dma_rx_crci: Rx channel rate control interface number
 * @clk_off_timer: Timer to poll DMA event completion before clock off
 * @clk_off_delay: clk_off_timer poll interval
 * @clk_state: overall clock state
 * @clk_req_off_state: post flush clock states
 * @rx_wakeup: optional rx_wakeup feature related data
 * @exit_lpm_cb: optional callback to exit low power mode
 *
 * Low level serial port structure.
 */
struct msm_hs_port {
	struct uart_port uport;
	unsigned long imr_reg;
	struct clk *clk;
	struct msm_hs_tx tx;
	struct msm_hs_rx rx;

	int dma_tx_channel;
	int dma_rx_channel;
	int dma_tx_crci;
	int dma_rx_crci;

	struct hrtimer clk_off_timer;
	ktime_t clk_off_delay;
	enum msm_hs_clk_states_e clk_state;
	enum msm_hs_clk_req_off_state_e clk_req_off_state;

	struct msm_hs_rx_wakeup rx_wakeup;
	void (*exit_lpm_cb)(struct uart_port *);
};

#define MSM_UARTDM_BURST_SIZE 16   /* DM burst size (in bytes) */
#define UARTDM_TX_BUF_SIZE UART_XMIT_SIZE
#define UARTDM_RX_BUF_SIZE 512

#define UARTDM_NR 2

static struct msm_hs_port q_uart_port[UARTDM_NR];
static struct platform_driver msm_serial_hs_platform_driver;
static struct uart_driver msm_hs_driver;
static struct uart_ops msm_hs_ops;
static struct workqueue_struct *msm_hs_workqueue;

#define UARTDM_TO_MSM(uart_port) \
	container_of((uart_port), struct msm_hs_port, uport)

static unsigned int use_low_power_rx_wakeup(struct msm_hs_port
						   *msm_uport)
{
	return (msm_uport->rx_wakeup.irq >= 0);
}

static unsigned int msm_hs_read(struct uart_port *uport,
				       unsigned int offset)
{
	return ioread32(uport->membase + offset);
}

static void msm_hs_write(struct uart_port *uport, unsigned int offset,
				 unsigned int value)
{
	iowrite32(value, uport->membase + offset);
}

static void msm_hs_release_port(struct uart_port *port)
{
	iounmap(port->membase);
}

static int msm_hs_request_port(struct uart_port *port)
{
	port->membase = ioremap(port->mapbase, PAGE_SIZE);
	if (unlikely(!port->membase))
		return -ENOMEM;

	/* configure the CR Protection to Enable */
	msm_hs_write(port, UARTDM_CR_ADDR, CR_PROTECTION_EN);
	return 0;
}

static int msm_hs_remove(struct platform_device *pdev)
{

	struct msm_hs_port *msm_uport;
	struct device *dev;

	if (pdev->id < 0 || pdev->id >= UARTDM_NR) {
		printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id);
		return -EINVAL;
	}

	msm_uport = &q_uart_port[pdev->id];
	dev = msm_uport->uport.dev;

	dma_unmap_single(dev, msm_uport->rx.mapped_cmd_ptr, sizeof(dmov_box),
			 DMA_TO_DEVICE);
	dma_pool_free(msm_uport->rx.pool, msm_uport->rx.buffer,
		      msm_uport->rx.rbuffer);
	dma_pool_destroy(msm_uport->rx.pool);

	dma_unmap_single(dev, msm_uport->rx.cmdptr_dmaaddr, sizeof(u32),
			 DMA_TO_DEVICE);
	dma_unmap_single(dev, msm_uport->tx.mapped_cmd_ptr_ptr, sizeof(u32),
			 DMA_TO_DEVICE);
	dma_unmap_single(dev, msm_uport->tx.mapped_cmd_ptr, sizeof(dmov_box),
			 DMA_TO_DEVICE);

	uart_remove_one_port(&msm_hs_driver, &msm_uport->uport);
	clk_put(msm_uport->clk);

	/* Free the tx resources */
	kfree(msm_uport->tx.command_ptr);
	kfree(msm_uport->tx.command_ptr_ptr);

	/* Free the rx resources */
	kfree(msm_uport->rx.command_ptr);
	kfree(msm_uport->rx.command_ptr_ptr);

	iounmap(msm_uport->uport.membase);

	return 0;
}

static int msm_hs_init_clk_locked(struct uart_port *uport)
{
	int ret;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	ret = clk_enable(msm_uport->clk);
	if (ret) {
		printk(KERN_ERR "Error could not turn on UART clk\n");
		return ret;
	}

	/* Set up the MREG/NREG/DREG/MNDREG */
	ret = clk_set_rate(msm_uport->clk, uport->uartclk);
	if (ret) {
		printk(KERN_WARNING "Error setting clock rate on UART\n");
		clk_disable(msm_uport->clk);
		return ret;
	}

	msm_uport->clk_state = MSM_HS_CLK_ON;
	return 0;
}

/* Enable and Disable clocks  (Used for power management) */
static void msm_hs_pm(struct uart_port *uport, unsigned int state,
		      unsigned int oldstate)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	if (use_low_power_rx_wakeup(msm_uport) ||
	    msm_uport->exit_lpm_cb)
		return;  /* ignore linux PM states,
			    use msm_hs_request_clock API */

	switch (state) {
	case 0:
		clk_enable(msm_uport->clk);
		break;
	case 3:
		clk_disable(msm_uport->clk);
		break;
	default:
		dev_err(uport->dev, "msm_serial: Unknown PM state %d\n",
			state);
	}
}

/*
 * programs the UARTDM_CSR register with correct bit rates
 *
 * Interrupts should be disabled before we are called, as
 * we modify Set Baud rate
 * Set receive stale interrupt level, dependent on Bit Rate
 * Goal is to have around 8 ms before indicate stale.
 * roundup (((Bit Rate * .008) / 10) + 1
 */
static void msm_hs_set_bps_locked(struct uart_port *uport,
				  unsigned int bps)
{
	unsigned long rxstale;
	unsigned long data;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	switch (bps) {
	case 300:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_75);
		rxstale = 1;
		break;
	case 600:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_150);
		rxstale = 1;
		break;
	case 1200:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_300);
		rxstale = 1;
		break;
	case 2400:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_600);
		rxstale = 1;
		break;
	case 4800:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_1200);
		rxstale = 1;
		break;
	case 9600:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_2400);
		rxstale = 2;
		break;
	case 14400:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_3600);
		rxstale = 3;
		break;
	case 19200:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_4800);
		rxstale = 4;
		break;
	case 28800:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_7200);
		rxstale = 6;
		break;
	case 38400:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_9600);
		rxstale = 8;
		break;
	case 57600:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_14400);
		rxstale = 16;
		break;
	case 76800:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_19200);
		rxstale = 16;
		break;
	case 115200:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_28800);
		rxstale = 31;
		break;
	case 230400:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_57600);
		rxstale = 31;
		break;
	case 460800:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_115200);
		rxstale = 31;
		break;
	case 4000000:
	case 3686400:
	case 3200000:
	case 3500000:
	case 3000000:
	case 2500000:
	case 1500000:
	case 1152000:
	case 1000000:
	case 921600:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_115200);
		rxstale = 31;
		break;
	default:
		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_2400);
		/* default to 9600 */
		bps = 9600;
		rxstale = 2;
		break;
	}
	if (bps > 460800)
		uport->uartclk = bps * 16;
	else
		uport->uartclk = UARTCLK;

	if (clk_set_rate(msm_uport->clk, uport->uartclk)) {
		printk(KERN_WARNING "Error setting clock rate on UART\n");
		return;
	}

	data = rxstale & UARTDM_IPR_STALE_LSB_BMSK;
	data |= UARTDM_IPR_STALE_TIMEOUT_MSB_BMSK & (rxstale << 2);

	msm_hs_write(uport, UARTDM_IPR_ADDR, data);
}

/*
 * termios :  new ktermios
 * oldtermios:  old ktermios previous setting
 *
 * Configure the serial port
 */
static void msm_hs_set_termios(struct uart_port *uport,
			       struct ktermios *termios,
			       struct ktermios *oldtermios)
{
	unsigned int bps;
	unsigned long data;
	unsigned long flags;
	unsigned int c_cflag = termios->c_cflag;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	spin_lock_irqsave(&uport->lock, flags);
	clk_enable(msm_uport->clk);

	/* 300 is the minimum baud support by the driver  */
	bps = uart_get_baud_rate(uport, termios, oldtermios, 200, 4000000);

	/* Temporary remapping  200 BAUD to 3.2 mbps */
	if (bps == 200)
		bps = 3200000;

	msm_hs_set_bps_locked(uport, bps);

	data = msm_hs_read(uport, UARTDM_MR2_ADDR);
	data &= ~UARTDM_MR2_PARITY_MODE_BMSK;
	/* set parity */
	if (PARENB == (c_cflag & PARENB)) {
		if (PARODD == (c_cflag & PARODD))
			data |= ODD_PARITY;
		else if (CMSPAR == (c_cflag & CMSPAR))
			data |= SPACE_PARITY;
		else
			data |= EVEN_PARITY;
	}

	/* Set bits per char */
	data &= ~UARTDM_MR2_BITS_PER_CHAR_BMSK;

	switch (c_cflag & CSIZE) {
	case CS5:
		data |= FIVE_BPC;
		break;
	case CS6:
		data |= SIX_BPC;
		break;
	case CS7:
		data |= SEVEN_BPC;
		break;
	default:
		data |= EIGHT_BPC;
		break;
	}
	/* stop bits */
	if (c_cflag & CSTOPB) {
		data |= STOP_BIT_TWO;
	} else {
		/* otherwise 1 stop bit */
		data |= STOP_BIT_ONE;
	}
	data |= UARTDM_MR2_ERROR_MODE_BMSK;
	/* write parity/bits per char/stop bit configuration */
	msm_hs_write(uport, UARTDM_MR2_ADDR, data);

	/* Configure HW flow control */
	data = msm_hs_read(uport, UARTDM_MR1_ADDR);

	data &= ~(UARTDM_MR1_CTS_CTL_BMSK | UARTDM_MR1_RX_RDY_CTL_BMSK);

	if (c_cflag & CRTSCTS) {
		data |= UARTDM_MR1_CTS_CTL_BMSK;
		data |= UARTDM_MR1_RX_RDY_CTL_BMSK;
	}

	msm_hs_write(uport, UARTDM_MR1_ADDR, data);

	uport->ignore_status_mask = termios->c_iflag & INPCK;
	uport->ignore_status_mask |= termios->c_iflag & IGNPAR;
	uport->read_status_mask = (termios->c_cflag & CREAD);

	msm_hs_write(uport, UARTDM_IMR_ADDR, 0);

	/* Set Transmit software time out */
	uart_update_timeout(uport, c_cflag, bps);

	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_TX);

	if (msm_uport->rx.flush == FLUSH_NONE) {
		msm_uport->rx.flush = FLUSH_IGNORE;
		msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);
	}

	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);

	clk_disable(msm_uport->clk);
	spin_unlock_irqrestore(&uport->lock, flags);
}

/*
 *  Standard API, Transmitter
 *  Any character in the transmit shift register is sent
 */
static unsigned int msm_hs_tx_empty(struct uart_port *uport)
{
	unsigned int data;
	unsigned int ret = 0;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	clk_enable(msm_uport->clk);

	data = msm_hs_read(uport, UARTDM_SR_ADDR);
	if (data & UARTDM_SR_TXEMT_BMSK)
		ret = TIOCSER_TEMT;

	clk_disable(msm_uport->clk);

	return ret;
}

/*
 *  Standard API, Stop transmitter.
 *  Any character in the transmit shift register is sent as
 *  well as the current data mover transfer .
 */
static void msm_hs_stop_tx_locked(struct uart_port *uport)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	msm_uport->tx.tx_ready_int_en = 0;
}

/*
 *  Standard API, Stop receiver as soon as possible.
 *
 *  Function immediately terminates the operation of the
 *  channel receiver and any incoming characters are lost. None
 *  of the receiver status bits are affected by this command and
 *  characters that are already in the receive FIFO there.
 */
static void msm_hs_stop_rx_locked(struct uart_port *uport)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
	unsigned int data;

	clk_enable(msm_uport->clk);

	/* disable dlink */
	data = msm_hs_read(uport, UARTDM_DMEN_ADDR);
	data &= ~UARTDM_RX_DM_EN_BMSK;
	msm_hs_write(uport, UARTDM_DMEN_ADDR, data);

	/* Disable the receiver */
	if (msm_uport->rx.flush == FLUSH_NONE)
		msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);

	if (msm_uport->rx.flush != FLUSH_SHUTDOWN)
		msm_uport->rx.flush = FLUSH_STOP;

	clk_disable(msm_uport->clk);
}

/*  Transmit the next chunk of data */
static void msm_hs_submit_tx_locked(struct uart_port *uport)
{
	int left;
	int tx_count;
	dma_addr_t src_addr;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
	struct msm_hs_tx *tx = &msm_uport->tx;
	struct circ_buf *tx_buf = &msm_uport->uport.state->xmit;

	if (uart_circ_empty(tx_buf) || uport->state->port.tty->stopped) {
		msm_hs_stop_tx_locked(uport);
		return;
	}

	tx->dma_in_flight = 1;

	tx_count = uart_circ_chars_pending(tx_buf);

	if (UARTDM_TX_BUF_SIZE < tx_count)
		tx_count = UARTDM_TX_BUF_SIZE;

	left = UART_XMIT_SIZE - tx_buf->tail;

	if (tx_count > left)
		tx_count = left;

	src_addr = tx->dma_base + tx_buf->tail;
	dma_sync_single_for_device(uport->dev, src_addr, tx_count,
				   DMA_TO_DEVICE);

	tx->command_ptr->num_rows = (((tx_count + 15) >> 4) << 16) |
				     ((tx_count + 15) >> 4);
	tx->command_ptr->src_row_addr = src_addr;

	dma_sync_single_for_device(uport->dev, tx->mapped_cmd_ptr,
				   sizeof(dmov_box), DMA_TO_DEVICE);

	*tx->command_ptr_ptr = CMD_PTR_LP | DMOV_CMD_ADDR(tx->mapped_cmd_ptr);

	dma_sync_single_for_device(uport->dev, tx->mapped_cmd_ptr_ptr,
				   sizeof(u32), DMA_TO_DEVICE);

	/* Save tx_count to use in Callback */
	tx->tx_count = tx_count;
	msm_hs_write(uport, UARTDM_NCF_TX_ADDR, tx_count);

	/* Disable the tx_ready interrupt */
	msm_uport->imr_reg &= ~UARTDM_ISR_TX_READY_BMSK;
	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
	msm_dmov_enqueue_cmd(msm_uport->dma_tx_channel, &tx->xfer);
}

/* Start to receive the next chunk of data */
static void msm_hs_start_rx_locked(struct uart_port *uport)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);
	msm_hs_write(uport, UARTDM_DMRX_ADDR, UARTDM_RX_BUF_SIZE);
	msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_ENABLE);
	msm_uport->imr_reg |= UARTDM_ISR_RXLEV_BMSK;
	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);

	msm_uport->rx.flush = FLUSH_NONE;
	msm_dmov_enqueue_cmd(msm_uport->dma_rx_channel, &msm_uport->rx.xfer);

	/* might have finished RX and be ready to clock off */
	hrtimer_start(&msm_uport->clk_off_timer, msm_uport->clk_off_delay,
			HRTIMER_MODE_REL);
}

/* Enable the transmitter Interrupt */
static void msm_hs_start_tx_locked(struct uart_port *uport)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	clk_enable(msm_uport->clk);

	if (msm_uport->exit_lpm_cb)
		msm_uport->exit_lpm_cb(uport);

	if (msm_uport->tx.tx_ready_int_en == 0) {
		msm_uport->tx.tx_ready_int_en = 1;
		msm_hs_submit_tx_locked(uport);
	}

	clk_disable(msm_uport->clk);
}

/*
 *  This routine is called when we are done with a DMA transfer
 *
 *  This routine is registered with Data mover when we set
 *  up a Data Mover transfer. It is called from Data mover ISR
 *  when the DMA transfer is done.
 */
static void msm_hs_dmov_tx_callback(struct msm_dmov_cmd *cmd_ptr,
					unsigned int result,
					struct msm_dmov_errdata *err)
{
	unsigned long flags;
	struct msm_hs_port *msm_uport;

	/* DMA did not finish properly */
	WARN_ON((((result & RSLT_FIFO_CNTR_BMSK) >> 28) == 1) &&
		!(result & RSLT_VLD));

	msm_uport = container_of(cmd_ptr, struct msm_hs_port, tx.xfer);

	spin_lock_irqsave(&msm_uport->uport.lock, flags);
	clk_enable(msm_uport->clk);

	msm_uport->imr_reg |= UARTDM_ISR_TX_READY_BMSK;
	msm_hs_write(&msm_uport->uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);

	clk_disable(msm_uport->clk);
	spin_unlock_irqrestore(&msm_uport->uport.lock, flags);
}

/*
 * This routine is called when we are done with a DMA transfer or the
 * a flush has been sent to the data mover driver.
 *
 * This routine is registered with Data mover when we set up a Data Mover
 *  transfer. It is called from Data mover ISR when the DMA transfer is done.
 */
static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr,
					unsigned int result,
					struct msm_dmov_errdata *err)
{
	int retval;
	int rx_count;
	unsigned long status;
	unsigned int error_f = 0;
	unsigned long flags;
	unsigned int flush;
	struct tty_struct *tty;
	struct tty_port *port;
	struct uart_port *uport;
	struct msm_hs_port *msm_uport;

	msm_uport = container_of(cmd_ptr, struct msm_hs_port, rx.xfer);
	uport = &msm_uport->uport;

	spin_lock_irqsave(&uport->lock, flags);
	clk_enable(msm_uport->clk);

	port = &uport->state->port;
	tty = port->tty;

	msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE);

	status = msm_hs_read(uport, UARTDM_SR_ADDR);

	/* overflow is not connect to data in a FIFO */
	if (unlikely((status & UARTDM_SR_OVERRUN_BMSK) &&
		     (uport->read_status_mask & CREAD))) {
		tty_insert_flip_char(port, 0, TTY_OVERRUN);
		uport->icount.buf_overrun++;
		error_f = 1;
	}

	if (!(uport->ignore_status_mask & INPCK))
		status = status & ~(UARTDM_SR_PAR_FRAME_BMSK);

	if (unlikely(status & UARTDM_SR_PAR_FRAME_BMSK)) {
		/* Can not tell difference between parity & frame error */
		uport->icount.parity++;
		error_f = 1;
		if (uport->ignore_status_mask & IGNPAR)
			tty_insert_flip_char(port, 0, TTY_PARITY);
	}

	if (error_f)
		msm_hs_write(uport, UARTDM_CR_ADDR, RESET_ERROR_STATUS);

	if (msm_uport->clk_req_off_state == CLK_REQ_OFF_FLUSH_ISSUED)
		msm_uport->clk_req_off_state = CLK_REQ_OFF_RXSTALE_FLUSHED;

	flush = msm_uport->rx.flush;
	if (flush == FLUSH_IGNORE)
		msm_hs_start_rx_locked(uport);
	if (flush == FLUSH_STOP)
		msm_uport->rx.flush = FLUSH_SHUTDOWN;
	if (flush >= FLUSH_DATA_INVALID)
		goto out;

	rx_count = msm_hs_read(uport, UARTDM_RX_TOTAL_SNAP_ADDR);

	if (0 != (uport->read_status_mask & CREAD)) {
		retval = tty_insert_flip_string(port, msm_uport->rx.buffer,
						rx_count);
		BUG_ON(retval != rx_count);
	}

	msm_hs_start_rx_locked(uport);

out:
	clk_disable(msm_uport->clk);

	spin_unlock_irqrestore(&uport->lock, flags);

	if (flush < FLUSH_DATA_INVALID)
		queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work);
}

static void msm_hs_tty_flip_buffer_work(struct work_struct *work)
{
	struct msm_hs_port *msm_uport =
			container_of(work, struct msm_hs_port, rx.tty_work);
	struct tty_struct *tty = msm_uport->uport.state->port.tty;

	tty_flip_buffer_push(tty);
}

/*
 *  Standard API, Current states of modem control inputs
 *
 * Since CTS can be handled entirely by HARDWARE we always
 * indicate clear to send and count on the TX FIFO to block when
 * it fills up.
 *
 * - TIOCM_DCD
 * - TIOCM_CTS
 * - TIOCM_DSR
 * - TIOCM_RI
 *  (Unsupported) DCD and DSR will return them high. RI will return low.
 */
static unsigned int msm_hs_get_mctrl_locked(struct uart_port *uport)
{
	return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS;
}

/*
 * True enables UART auto RFR, which indicates we are ready for data if the RX
 * buffer is not full. False disables auto RFR, and deasserts RFR to indicate
 * we are not ready for data. Must be called with UART clock on.
 */
static void set_rfr_locked(struct uart_port *uport, int auto_rfr)
{
	unsigned int data;

	data = msm_hs_read(uport, UARTDM_MR1_ADDR);

	if (auto_rfr) {
		/* enable auto ready-for-receiving */
		data |= UARTDM_MR1_RX_RDY_CTL_BMSK;
		msm_hs_write(uport, UARTDM_MR1_ADDR, data);
	} else {
		/* disable auto ready-for-receiving */
		data &= ~UARTDM_MR1_RX_RDY_CTL_BMSK;
		msm_hs_write(uport, UARTDM_MR1_ADDR, data);
		/* RFR is active low, set high */
		msm_hs_write(uport, UARTDM_CR_ADDR, RFR_HIGH);
	}
}

/*
 *  Standard API, used to set or clear RFR
 */
static void msm_hs_set_mctrl_locked(struct uart_port *uport,
				    unsigned int mctrl)
{
	unsigned int auto_rfr;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	clk_enable(msm_uport->clk);

	auto_rfr = TIOCM_RTS & mctrl ? 1 : 0;
	set_rfr_locked(uport, auto_rfr);

	clk_disable(msm_uport->clk);
}

/* Standard API, Enable modem status (CTS) interrupt  */
static void msm_hs_enable_ms_locked(struct uart_port *uport)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	clk_enable(msm_uport->clk);

	/* Enable DELTA_CTS Interrupt */
	msm_uport->imr_reg |= UARTDM_ISR_DELTA_CTS_BMSK;
	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);

	clk_disable(msm_uport->clk);

}

/*
 *  Standard API, Break Signal
 *
 * Control the transmission of a break signal. ctl eq 0 => break
 * signal terminate ctl ne 0 => start break signal
 */
static void msm_hs_break_ctl(struct uart_port *uport, int ctl)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	clk_enable(msm_uport->clk);
	msm_hs_write(uport, UARTDM_CR_ADDR, ctl ? START_BREAK : STOP_BREAK);
	clk_disable(msm_uport->clk);
}

static void msm_hs_config_port(struct uart_port *uport, int cfg_flags)
{
	unsigned long flags;

	spin_lock_irqsave(&uport->lock, flags);
	if (cfg_flags & UART_CONFIG_TYPE) {
		uport->type = PORT_MSM;
		msm_hs_request_port(uport);
	}
	spin_unlock_irqrestore(&uport->lock, flags);
}

/*  Handle CTS changes (Called from interrupt handler) */
static void msm_hs_handle_delta_cts_locked(struct uart_port *uport)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	clk_enable(msm_uport->clk);

	/* clear interrupt */
	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_CTS);
	uport->icount.cts++;

	clk_disable(msm_uport->clk);

	/* clear the IOCTL TIOCMIWAIT if called */
	wake_up_interruptible(&uport->state->port.delta_msr_wait);
}

/* check if the TX path is flushed, and if so clock off
 * returns 0 did not clock off, need to retry (still sending final byte)
 *        -1 did not clock off, do not retry
 *         1 if we clocked off
 */
static int msm_hs_check_clock_off_locked(struct uart_port *uport)
{
	unsigned long sr_status;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
	struct circ_buf *tx_buf = &uport->state->xmit;

	/* Cancel if tx tty buffer is not empty, dma is in flight,
	 * or tx fifo is not empty, or rx fifo is not empty */
	if (msm_uport->clk_state != MSM_HS_CLK_REQUEST_OFF ||
	    !uart_circ_empty(tx_buf) || msm_uport->tx.dma_in_flight ||
	    (msm_uport->imr_reg & UARTDM_ISR_TXLEV_BMSK) ||
	    !(msm_uport->imr_reg & UARTDM_ISR_RXLEV_BMSK))  {
		return -1;
	}

	/* Make sure the uart is finished with the last byte */
	sr_status = msm_hs_read(uport, UARTDM_SR_ADDR);
	if (!(sr_status & UARTDM_SR_TXEMT_BMSK))
		return 0;  /* retry */

	/* Make sure forced RXSTALE flush complete */
	switch (msm_uport->clk_req_off_state) {
	case CLK_REQ_OFF_START:
		msm_uport->clk_req_off_state = CLK_REQ_OFF_RXSTALE_ISSUED;
		msm_hs_write(uport, UARTDM_CR_ADDR, FORCE_STALE_EVENT);
		return 0;  /* RXSTALE flush not complete - retry */
	case CLK_REQ_OFF_RXSTALE_ISSUED:
	case CLK_REQ_OFF_FLUSH_ISSUED:
		return 0;  /* RXSTALE flush not complete - retry */
	case CLK_REQ_OFF_RXSTALE_FLUSHED:
		break;  /* continue */
	}

	if (msm_uport->rx.flush != FLUSH_SHUTDOWN) {
		if (msm_uport->rx.flush == FLUSH_NONE)
			msm_hs_stop_rx_locked(uport);
		return 0;  /* come back later to really clock off */
	}

	/* we really want to clock off */
	clk_disable(msm_uport->clk);
	msm_uport->clk_state = MSM_HS_CLK_OFF;

	if (use_low_power_rx_wakeup(msm_uport)) {
		msm_uport->rx_wakeup.ignore = 1;
		enable_irq(msm_uport->rx_wakeup.irq);
	}
	return 1;
}

static enum hrtimer_restart msm_hs_clk_off_retry(struct hrtimer *timer)
{
	unsigned long flags;
	int ret = HRTIMER_NORESTART;
	struct msm_hs_port *msm_uport = container_of(timer, struct msm_hs_port,
						     clk_off_timer);
	struct uart_port *uport = &msm_uport->uport;

	spin_lock_irqsave(&uport->lock, flags);

	if (!msm_hs_check_clock_off_locked(uport)) {
		hrtimer_forward_now(timer, msm_uport->clk_off_delay);
		ret = HRTIMER_RESTART;
	}

	spin_unlock_irqrestore(&uport->lock, flags);

	return ret;
}

static irqreturn_t msm_hs_isr(int irq, void *dev)
{
	unsigned long flags;
	unsigned long isr_status;
	struct msm_hs_port *msm_uport = dev;
	struct uart_port *uport = &msm_uport->uport;
	struct circ_buf *tx_buf = &uport->state->xmit;
	struct msm_hs_tx *tx = &msm_uport->tx;
	struct msm_hs_rx *rx = &msm_uport->rx;

	spin_lock_irqsave(&uport->lock, flags);

	isr_status = msm_hs_read(uport, UARTDM_MISR_ADDR);

	/* Uart RX starting */
	if (isr_status & UARTDM_ISR_RXLEV_BMSK) {
		msm_uport->imr_reg &= ~UARTDM_ISR_RXLEV_BMSK;
		msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
	}
	/* Stale rx interrupt */
	if (isr_status & UARTDM_ISR_RXSTALE_BMSK) {
		msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE);
		msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);

		if (msm_uport->clk_req_off_state == CLK_REQ_OFF_RXSTALE_ISSUED)
			msm_uport->clk_req_off_state =
					CLK_REQ_OFF_FLUSH_ISSUED;
		if (rx->flush == FLUSH_NONE) {
			rx->flush = FLUSH_DATA_READY;
			msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);
		}
	}
	/* tx ready interrupt */
	if (isr_status & UARTDM_ISR_TX_READY_BMSK) {
		/* Clear  TX Ready */
		msm_hs_write(uport, UARTDM_CR_ADDR, CLEAR_TX_READY);

		if (msm_uport->clk_state == MSM_HS_CLK_REQUEST_OFF) {
			msm_uport->imr_reg |= UARTDM_ISR_TXLEV_BMSK;
			msm_hs_write(uport, UARTDM_IMR_ADDR,
				     msm_uport->imr_reg);
		}

		/* Complete DMA TX transactions and submit new transactions */
		tx_buf->tail = (tx_buf->tail + tx->tx_count) & ~UART_XMIT_SIZE;

		tx->dma_in_flight = 0;

		uport->icount.tx += tx->tx_count;
		if (tx->tx_ready_int_en)
			msm_hs_submit_tx_locked(uport);

		if (uart_circ_chars_pending(tx_buf) < WAKEUP_CHARS)
			uart_write_wakeup(uport);
	}
	if (isr_status & UARTDM_ISR_TXLEV_BMSK) {
		/* TX FIFO is empty */
		msm_uport->imr_reg &= ~UARTDM_ISR_TXLEV_BMSK;
		msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
		if (!msm_hs_check_clock_off_locked(uport))
			hrtimer_start(&msm_uport->clk_off_timer,
				      msm_uport->clk_off_delay,
				      HRTIMER_MODE_REL);
	}

	/* Change in CTS interrupt */
	if (isr_status & UARTDM_ISR_DELTA_CTS_BMSK)
		msm_hs_handle_delta_cts_locked(uport);

	spin_unlock_irqrestore(&uport->lock, flags);

	return IRQ_HANDLED;
}

void msm_hs_request_clock_off_locked(struct uart_port *uport)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	if (msm_uport->clk_state == MSM_HS_CLK_ON) {
		msm_uport->clk_state = MSM_HS_CLK_REQUEST_OFF;
		msm_uport->clk_req_off_state = CLK_REQ_OFF_START;
		if (!use_low_power_rx_wakeup(msm_uport))
			set_rfr_locked(uport, 0);
		msm_uport->imr_reg |= UARTDM_ISR_TXLEV_BMSK;
		msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
	}
}

/**
 * msm_hs_request_clock_off - request to (i.e. asynchronously) turn off uart
 * clock once pending TX is flushed and Rx DMA command is terminated.
 * @uport: uart_port structure for the device instance.
 *
 * This functions puts the device into a partially active low power mode. It
 * waits to complete all pending tx transactions, flushes ongoing Rx DMA
 * command and terminates UART side Rx transaction, puts UART HW in non DMA
 * mode and then clocks off the device. A client calls this when no UART
 * data is expected. msm_request_clock_on() must be called before any further
 * UART can be sent or received.
 */
void msm_hs_request_clock_off(struct uart_port *uport)
{
	unsigned long flags;

	spin_lock_irqsave(&uport->lock, flags);
	msm_hs_request_clock_off_locked(uport);
	spin_unlock_irqrestore(&uport->lock, flags);
}

void msm_hs_request_clock_on_locked(struct uart_port *uport)
{
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
	unsigned int data;

	switch (msm_uport->clk_state) {
	case MSM_HS_CLK_OFF:
		clk_enable(msm_uport->clk);
		disable_irq_nosync(msm_uport->rx_wakeup.irq);
		/* fall-through */
	case MSM_HS_CLK_REQUEST_OFF:
		if (msm_uport->rx.flush == FLUSH_STOP ||
		    msm_uport->rx.flush == FLUSH_SHUTDOWN) {
			msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
			data = msm_hs_read(uport, UARTDM_DMEN_ADDR);
			data |= UARTDM_RX_DM_EN_BMSK;
			msm_hs_write(uport, UARTDM_DMEN_ADDR, data);
		}
		hrtimer_try_to_cancel(&msm_uport->clk_off_timer);
		if (msm_uport->rx.flush == FLUSH_SHUTDOWN)
			msm_hs_start_rx_locked(uport);
		if (!use_low_power_rx_wakeup(msm_uport))
			set_rfr_locked(uport, 1);
		if (msm_uport->rx.flush == FLUSH_STOP)
			msm_uport->rx.flush = FLUSH_IGNORE;
		msm_uport->clk_state = MSM_HS_CLK_ON;
		break;
	case MSM_HS_CLK_ON:
		break;
	case MSM_HS_CLK_PORT_OFF:
		break;
	}
}

/**
 * msm_hs_request_clock_on - Switch the device from partially active low
 * power mode to fully active (i.e. clock on) mode.
 * @uport: uart_port structure for the device.
 *
 * This function switches on the input clock, puts UART HW into DMA mode
 * and enqueues an Rx DMA command if the device was in partially active
 * mode. It has no effect if called with the device in inactive state.
 */
void msm_hs_request_clock_on(struct uart_port *uport)
{
	unsigned long flags;

	spin_lock_irqsave(&uport->lock, flags);
	msm_hs_request_clock_on_locked(uport);
	spin_unlock_irqrestore(&uport->lock, flags);
}

static irqreturn_t msm_hs_rx_wakeup_isr(int irq, void *dev)
{
	unsigned int wakeup = 0;
	unsigned long flags;
	struct msm_hs_port *msm_uport = dev;
	struct uart_port *uport = &msm_uport->uport;

	spin_lock_irqsave(&uport->lock, flags);
	if (msm_uport->clk_state == MSM_HS_CLK_OFF) {
		/* ignore the first irq - it is a pending irq that occurred
		 * before enable_irq() */
		if (msm_uport->rx_wakeup.ignore)
			msm_uport->rx_wakeup.ignore = 0;
		else
			wakeup = 1;
	}

	if (wakeup) {
		/* the uart was clocked off during an rx, wake up and
		 * optionally inject char into tty rx */
		msm_hs_request_clock_on_locked(uport);
		if (msm_uport->rx_wakeup.inject_rx) {
			tty_insert_flip_char(&uport->state->port,
					     msm_uport->rx_wakeup.rx_to_inject,
					     TTY_NORMAL);
			queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work);
		}
	}

	spin_unlock_irqrestore(&uport->lock, flags);

	return IRQ_HANDLED;
}

static const char *msm_hs_type(struct uart_port *port)
{
	return (port->type == PORT_MSM) ? "MSM_HS_UART" : NULL;
}

/* Called when port is opened */
static int msm_hs_startup(struct uart_port *uport)
{
	int ret;
	int rfr_level;
	unsigned long flags;
	unsigned int data;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
	struct circ_buf *tx_buf = &uport->state->xmit;
	struct msm_hs_tx *tx = &msm_uport->tx;
	struct msm_hs_rx *rx = &msm_uport->rx;

	rfr_level = uport->fifosize;
	if (rfr_level > 16)
		rfr_level -= 16;

	tx->dma_base = dma_map_single(uport->dev, tx_buf->buf, UART_XMIT_SIZE,
				      DMA_TO_DEVICE);

	/* do not let tty layer execute RX in global workqueue, use a
	 * dedicated workqueue managed by this driver */
	uport->state->port.low_latency = 1;

	/* turn on uart clk */
	ret = msm_hs_init_clk_locked(uport);
	if (unlikely(ret)) {
		printk(KERN_ERR "Turning uartclk failed!\n");
		goto err_msm_hs_init_clk;
	}

	/* Set auto RFR Level */
	data = msm_hs_read(uport, UARTDM_MR1_ADDR);
	data &= ~UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK;
	data &= ~UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK;
	data |= (UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK & (rfr_level << 2));
	data |= (UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK & rfr_level);
	msm_hs_write(uport, UARTDM_MR1_ADDR, data);

	/* Make sure RXSTALE count is non-zero */
	data = msm_hs_read(uport, UARTDM_IPR_ADDR);
	if (!data) {
		data |= 0x1f & UARTDM_IPR_STALE_LSB_BMSK;
		msm_hs_write(uport, UARTDM_IPR_ADDR, data);
	}

	/* Enable Data Mover Mode */
	data = UARTDM_TX_DM_EN_BMSK | UARTDM_RX_DM_EN_BMSK;
	msm_hs_write(uport, UARTDM_DMEN_ADDR, data);

	/* Reset TX */
	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_TX);
	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_ERROR_STATUS);
	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_BREAK_INT);
	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);
	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_CTS);
	msm_hs_write(uport, UARTDM_CR_ADDR, RFR_LOW);
	/* Turn on Uart Receiver */
	msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_RX_EN_BMSK);

	/* Turn on Uart Transmitter */
	msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_TX_EN_BMSK);

	/* Initialize the tx */
	tx->tx_ready_int_en = 0;
	tx->dma_in_flight = 0;

	tx->xfer.complete_func = msm_hs_dmov_tx_callback;
	tx->xfer.execute_func = NULL;

	tx->command_ptr->cmd = CMD_LC |
	    CMD_DST_CRCI(msm_uport->dma_tx_crci) | CMD_MODE_BOX;

	tx->command_ptr->src_dst_len = (MSM_UARTDM_BURST_SIZE << 16)
					   | (MSM_UARTDM_BURST_SIZE);

	tx->command_ptr->row_offset = (MSM_UARTDM_BURST_SIZE << 16);

	tx->command_ptr->dst_row_addr =
	    msm_uport->uport.mapbase + UARTDM_TF_ADDR;


	/* Turn on Uart Receive */
	rx->xfer.complete_func = msm_hs_dmov_rx_callback;
	rx->xfer.execute_func = NULL;

	rx->command_ptr->cmd = CMD_LC |
	    CMD_SRC_CRCI(msm_uport->dma_rx_crci) | CMD_MODE_BOX;

	rx->command_ptr->src_dst_len = (MSM_UARTDM_BURST_SIZE << 16)
					   | (MSM_UARTDM_BURST_SIZE);
	rx->command_ptr->row_offset =  MSM_UARTDM_BURST_SIZE;
	rx->command_ptr->src_row_addr = uport->mapbase + UARTDM_RF_ADDR;


	msm_uport->imr_reg |= UARTDM_ISR_RXSTALE_BMSK;
	/* Enable reading the current CTS, no harm even if CTS is ignored */
	msm_uport->imr_reg |= UARTDM_ISR_CURRENT_CTS_BMSK;

	msm_hs_write(uport, UARTDM_TFWR_ADDR, 0);  /* TXLEV on empty TX fifo */


	ret = request_irq(uport->irq, msm_hs_isr, IRQF_TRIGGER_HIGH,
			  "msm_hs_uart", msm_uport);
	if (unlikely(ret)) {
		printk(KERN_ERR "Request msm_hs_uart IRQ failed!\n");
		goto err_request_irq;
	}
	if (use_low_power_rx_wakeup(msm_uport)) {
		ret = request_irq(msm_uport->rx_wakeup.irq,
				  msm_hs_rx_wakeup_isr,
				  IRQF_TRIGGER_FALLING,
				  "msm_hs_rx_wakeup", msm_uport);
		if (unlikely(ret)) {
			printk(KERN_ERR "Request msm_hs_rx_wakeup IRQ failed!\n");
			free_irq(uport->irq, msm_uport);
			goto err_request_irq;
		}
		disable_irq(msm_uport->rx_wakeup.irq);
	}

	spin_lock_irqsave(&uport->lock, flags);

	msm_hs_write(uport, UARTDM_RFWR_ADDR, 0);
	msm_hs_start_rx_locked(uport);

	spin_unlock_irqrestore(&uport->lock, flags);
	ret = pm_runtime_set_active(uport->dev);
	if (ret)
		dev_err(uport->dev, "set active error:%d\n", ret);
	pm_runtime_enable(uport->dev);

	return 0;

err_request_irq:
err_msm_hs_init_clk:
	dma_unmap_single(uport->dev, tx->dma_base,
				UART_XMIT_SIZE, DMA_TO_DEVICE);
	return ret;
}

/* Initialize tx and rx data structures */
static int uartdm_init_port(struct uart_port *uport)
{
	int ret = 0;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
	struct msm_hs_tx *tx = &msm_uport->tx;
	struct msm_hs_rx *rx = &msm_uport->rx;

	/* Allocate the command pointer. Needs to be 64 bit aligned */
	tx->command_ptr = kmalloc(sizeof(dmov_box), GFP_KERNEL | __GFP_DMA);
	if (!tx->command_ptr)
		return -ENOMEM;

	tx->command_ptr_ptr = kmalloc(sizeof(u32), GFP_KERNEL | __GFP_DMA);
	if (!tx->command_ptr_ptr) {
		ret = -ENOMEM;
		goto err_tx_command_ptr_ptr;
	}

	tx->mapped_cmd_ptr = dma_map_single(uport->dev, tx->command_ptr,
					    sizeof(dmov_box), DMA_TO_DEVICE);
	tx->mapped_cmd_ptr_ptr = dma_map_single(uport->dev,
						tx->command_ptr_ptr,
						sizeof(u32), DMA_TO_DEVICE);
	tx->xfer.cmdptr = DMOV_CMD_ADDR(tx->mapped_cmd_ptr_ptr);

	init_waitqueue_head(&rx->wait);

	rx->pool = dma_pool_create("rx_buffer_pool", uport->dev,
				   UARTDM_RX_BUF_SIZE, 16, 0);
	if (!rx->pool) {
		pr_err("%s(): cannot allocate rx_buffer_pool", __func__);
		ret = -ENOMEM;
		goto err_dma_pool_create;
	}

	rx->buffer = dma_pool_alloc(rx->pool, GFP_KERNEL, &rx->rbuffer);
	if (!rx->buffer) {
		pr_err("%s(): cannot allocate rx->buffer", __func__);
		ret = -ENOMEM;
		goto err_dma_pool_alloc;
	}

	/* Allocate the command pointer. Needs to be 64 bit aligned */
	rx->command_ptr = kmalloc(sizeof(dmov_box), GFP_KERNEL | __GFP_DMA);
	if (!rx->command_ptr) {
		pr_err("%s(): cannot allocate rx->command_ptr", __func__);
		ret = -ENOMEM;
		goto err_rx_command_ptr;
	}

	rx->command_ptr_ptr = kmalloc(sizeof(u32), GFP_KERNEL | __GFP_DMA);
	if (!rx->command_ptr_ptr) {
		pr_err("%s(): cannot allocate rx->command_ptr_ptr", __func__);
		ret = -ENOMEM;
		goto err_rx_command_ptr_ptr;
	}

	rx->command_ptr->num_rows = ((UARTDM_RX_BUF_SIZE >> 4) << 16) |
					 (UARTDM_RX_BUF_SIZE >> 4);

	rx->command_ptr->dst_row_addr = rx->rbuffer;

	rx->mapped_cmd_ptr = dma_map_single(uport->dev, rx->command_ptr,
					    sizeof(dmov_box), DMA_TO_DEVICE);

	*rx->command_ptr_ptr = CMD_PTR_LP | DMOV_CMD_ADDR(rx->mapped_cmd_ptr);

	rx->cmdptr_dmaaddr = dma_map_single(uport->dev, rx->command_ptr_ptr,
					    sizeof(u32), DMA_TO_DEVICE);
	rx->xfer.cmdptr = DMOV_CMD_ADDR(rx->cmdptr_dmaaddr);

	INIT_WORK(&rx->tty_work, msm_hs_tty_flip_buffer_work);

	return ret;

err_rx_command_ptr_ptr:
	kfree(rx->command_ptr);
err_rx_command_ptr:
	dma_pool_free(msm_uport->rx.pool, msm_uport->rx.buffer,
						msm_uport->rx.rbuffer);
err_dma_pool_alloc:
	dma_pool_destroy(msm_uport->rx.pool);
err_dma_pool_create:
	dma_unmap_single(uport->dev, msm_uport->tx.mapped_cmd_ptr_ptr,
				sizeof(u32), DMA_TO_DEVICE);
	dma_unmap_single(uport->dev, msm_uport->tx.mapped_cmd_ptr,
				sizeof(dmov_box), DMA_TO_DEVICE);
	kfree(msm_uport->tx.command_ptr_ptr);
err_tx_command_ptr_ptr:
	kfree(msm_uport->tx.command_ptr);
	return ret;
}

static int msm_hs_probe(struct platform_device *pdev)
{
	int ret;
	struct uart_port *uport;
	struct msm_hs_port *msm_uport;
	struct resource *resource;
	const struct msm_serial_hs_platform_data *pdata =
						pdev->dev.platform_data;

	if (pdev->id < 0 || pdev->id >= UARTDM_NR) {
		printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id);
		return -EINVAL;
	}

	msm_uport = &q_uart_port[pdev->id];
	uport = &msm_uport->uport;

	uport->dev = &pdev->dev;

	resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (unlikely(!resource))
		return -ENXIO;

	uport->mapbase = resource->start;
	uport->irq = platform_get_irq(pdev, 0);
	if (unlikely(uport->irq < 0))
		return -ENXIO;

	if (unlikely(irq_set_irq_wake(uport->irq, 1)))
		return -ENXIO;

	if (pdata == NULL || pdata->rx_wakeup_irq < 0)
		msm_uport->rx_wakeup.irq = -1;
	else {
		msm_uport->rx_wakeup.irq = pdata->rx_wakeup_irq;
		msm_uport->rx_wakeup.ignore = 1;
		msm_uport->rx_wakeup.inject_rx = pdata->inject_rx_on_wakeup;
		msm_uport->rx_wakeup.rx_to_inject = pdata->rx_to_inject;

		if (unlikely(msm_uport->rx_wakeup.irq < 0))
			return -ENXIO;

		if (unlikely(irq_set_irq_wake(msm_uport->rx_wakeup.irq, 1)))
			return -ENXIO;
	}

	if (pdata == NULL)
		msm_uport->exit_lpm_cb = NULL;
	else
		msm_uport->exit_lpm_cb = pdata->exit_lpm_cb;

	resource = platform_get_resource_byname(pdev, IORESOURCE_DMA,
						"uartdm_channels");
	if (unlikely(!resource))
		return -ENXIO;

	msm_uport->dma_tx_channel = resource->start;
	msm_uport->dma_rx_channel = resource->end;

	resource = platform_get_resource_byname(pdev, IORESOURCE_DMA,
						"uartdm_crci");
	if (unlikely(!resource))
		return -ENXIO;

	msm_uport->dma_tx_crci = resource->start;
	msm_uport->dma_rx_crci = resource->end;

	uport->iotype = UPIO_MEM;
	uport->fifosize = UART_FIFOSIZE;
	uport->ops = &msm_hs_ops;
	uport->flags = UPF_BOOT_AUTOCONF;
	uport->uartclk = UARTCLK;
	msm_uport->imr_reg = 0x0;
	msm_uport->clk = clk_get(&pdev->dev, "uartdm_clk");
	if (IS_ERR(msm_uport->clk))
		return PTR_ERR(msm_uport->clk);

	ret = uartdm_init_port(uport);
	if (unlikely(ret))
		return ret;

	msm_uport->clk_state = MSM_HS_CLK_PORT_OFF;
	hrtimer_init(&msm_uport->clk_off_timer, CLOCK_MONOTONIC,
		     HRTIMER_MODE_REL);
	msm_uport->clk_off_timer.function = msm_hs_clk_off_retry;
	msm_uport->clk_off_delay = ktime_set(0, 1000000);  /* 1ms */

	uport->line = pdev->id;
	return uart_add_one_port(&msm_hs_driver, uport);
}

static int __init msm_serial_hs_init(void)
{
	int ret, i;

	/* Init all UARTS as non-configured */
	for (i = 0; i < UARTDM_NR; i++)
		q_uart_port[i].uport.type = PORT_UNKNOWN;

	msm_hs_workqueue = create_singlethread_workqueue("msm_serial_hs");
	if (unlikely(!msm_hs_workqueue))
		return -ENOMEM;

	ret = uart_register_driver(&msm_hs_driver);
	if (unlikely(ret)) {
		printk(KERN_ERR "%s failed to load\n", __func__);
		goto err_uart_register_driver;
	}

	ret = platform_driver_register(&msm_serial_hs_platform_driver);
	if (ret) {
		printk(KERN_ERR "%s failed to load\n", __func__);
		goto err_platform_driver_register;
	}

	return ret;

err_platform_driver_register:
	uart_unregister_driver(&msm_hs_driver);
err_uart_register_driver:
	destroy_workqueue(msm_hs_workqueue);
	return ret;
}
module_init(msm_serial_hs_init);

/*
 *  Called by the upper layer when port is closed.
 *     - Disables the port
 *     - Unhook the ISR
 */
static void msm_hs_shutdown(struct uart_port *uport)
{
	unsigned long flags;
	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);

	BUG_ON(msm_uport->rx.flush < FLUSH_STOP);

	spin_lock_irqsave(&uport->lock, flags);
	clk_enable(msm_uport->clk);

	/* Disable the transmitter */
	msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_TX_DISABLE_BMSK);
	/* Disable the receiver */
	msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_RX_DISABLE_BMSK);

	pm_runtime_disable(uport->dev);
	pm_runtime_set_suspended(uport->dev);

	/* Free the interrupt */
	free_irq(uport->irq, msm_uport);
	if (use_low_power_rx_wakeup(msm_uport))
		free_irq(msm_uport->rx_wakeup.irq, msm_uport);

	msm_uport->imr_reg = 0;
	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);

	wait_event(msm_uport->rx.wait, msm_uport->rx.flush == FLUSH_SHUTDOWN);

	clk_disable(msm_uport->clk);  /* to balance local clk_enable() */
	if (msm_uport->clk_state != MSM_HS_CLK_OFF)
		clk_disable(msm_uport->clk);  /* to balance clk_state */
	msm_uport->clk_state = MSM_HS_CLK_PORT_OFF;

	dma_unmap_single(uport->dev, msm_uport->tx.dma_base,
			 UART_XMIT_SIZE, DMA_TO_DEVICE);

	spin_unlock_irqrestore(&uport->lock, flags);

	if (cancel_work_sync(&msm_uport->rx.tty_work))
		msm_hs_tty_flip_buffer_work(&msm_uport->rx.tty_work);
}

static void __exit msm_serial_hs_exit(void)
{
	flush_workqueue(msm_hs_workqueue);
	destroy_workqueue(msm_hs_workqueue);
	platform_driver_unregister(&msm_serial_hs_platform_driver);
	uart_unregister_driver(&msm_hs_driver);
}
module_exit(msm_serial_hs_exit);

#ifdef CONFIG_PM_RUNTIME
static int msm_hs_runtime_idle(struct device *dev)
{
	/*
	 * returning success from idle results in runtime suspend to be
	 * called
	 */
	return 0;
}

static int msm_hs_runtime_resume(struct device *dev)
{
	struct platform_device *pdev = container_of(dev, struct
						    platform_device, dev);
	struct msm_hs_port *msm_uport = &q_uart_port[pdev->id];

	msm_hs_request_clock_on(&msm_uport->uport);
	return 0;
}

static int msm_hs_runtime_suspend(struct device *dev)
{
	struct platform_device *pdev = container_of(dev, struct
						    platform_device, dev);
	struct msm_hs_port *msm_uport = &q_uart_port[pdev->id];

	msm_hs_request_clock_off(&msm_uport->uport);
	return 0;
}
#else
#define msm_hs_runtime_idle NULL
#define msm_hs_runtime_resume NULL
#define msm_hs_runtime_suspend NULL
#endif

static const struct dev_pm_ops msm_hs_dev_pm_ops = {
	.runtime_suspend = msm_hs_runtime_suspend,
	.runtime_resume  = msm_hs_runtime_resume,
	.runtime_idle    = msm_hs_runtime_idle,
};

static struct platform_driver msm_serial_hs_platform_driver = {
	.probe = msm_hs_probe,
	.remove = msm_hs_remove,
	.driver = {
		.name = "msm_serial_hs",
		.owner = THIS_MODULE,
		.pm   = &msm_hs_dev_pm_ops,
	},
};

static struct uart_driver msm_hs_driver = {
	.owner = THIS_MODULE,
	.driver_name = "msm_serial_hs",
	.dev_name = "ttyHS",
	.nr = UARTDM_NR,
	.cons = 0,
};

static struct uart_ops msm_hs_ops = {
	.tx_empty = msm_hs_tx_empty,
	.set_mctrl = msm_hs_set_mctrl_locked,
	.get_mctrl = msm_hs_get_mctrl_locked,
	.stop_tx = msm_hs_stop_tx_locked,
	.start_tx = msm_hs_start_tx_locked,
	.stop_rx = msm_hs_stop_rx_locked,
	.enable_ms = msm_hs_enable_ms_locked,
	.break_ctl = msm_hs_break_ctl,
	.startup = msm_hs_startup,
	.shutdown = msm_hs_shutdown,
	.set_termios = msm_hs_set_termios,
	.pm = msm_hs_pm,
	.type = msm_hs_type,
	.config_port = msm_hs_config_port,
	.release_port = msm_hs_release_port,
	.request_port = msm_hs_request_port,
};

MODULE_DESCRIPTION("High Speed UART Driver for the MSM chipset");
MODULE_VERSION("1.2");
MODULE_LICENSE("GPL v2");