2 * This file is provided under a dual BSD/GPLv2 license. When using or
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10 * it under the terms of version 2 of the GNU General Public License as
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16 * General Public License for more details.
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50 * Supports the SMBus Message Transport (SMT) in the Intel Atom Processor
51 * S12xx Product Family.
53 * Features supported by this driver:
56 * Block process call transaction no
60 #include <linux/module.h>
61 #include <linux/pci.h>
62 #include <linux/kernel.h>
63 #include <linux/stddef.h>
64 #include <linux/completion.h>
65 #include <linux/dma-mapping.h>
66 #include <linux/i2c.h>
67 #include <linux/acpi.h>
68 #include <linux/interrupt.h>
70 #include <linux/io-64-nonatomic-lo-hi.h>
72 /* PCI Address Constants */
75 /* PCI DIDs for the Intel SMBus Message Transport (SMT) Devices */
76 #define PCI_DEVICE_ID_INTEL_S1200_SMT0 0x0c59
77 #define PCI_DEVICE_ID_INTEL_S1200_SMT1 0x0c5a
78 #define PCI_DEVICE_ID_INTEL_AVOTON_SMT 0x1f15
80 #define ISMT_DESC_ENTRIES 2 /* number of descriptor entries */
81 #define ISMT_MAX_RETRIES 3 /* number of SMBus retries to attempt */
83 /* Hardware Descriptor Constants - Control Field */
84 #define ISMT_DESC_CWRL 0x01 /* Command/Write Length */
85 #define ISMT_DESC_BLK 0X04 /* Perform Block Transaction */
86 #define ISMT_DESC_FAIR 0x08 /* Set fairness flag upon successful arbit. */
87 #define ISMT_DESC_PEC 0x10 /* Packet Error Code */
88 #define ISMT_DESC_I2C 0x20 /* I2C Enable */
89 #define ISMT_DESC_INT 0x40 /* Interrupt */
90 #define ISMT_DESC_SOE 0x80 /* Stop On Error */
92 /* Hardware Descriptor Constants - Status Field */
93 #define ISMT_DESC_SCS 0x01 /* Success */
94 #define ISMT_DESC_DLTO 0x04 /* Data Low Time Out */
95 #define ISMT_DESC_NAK 0x08 /* NAK Received */
96 #define ISMT_DESC_CRC 0x10 /* CRC Error */
97 #define ISMT_DESC_CLTO 0x20 /* Clock Low Time Out */
98 #define ISMT_DESC_COL 0x40 /* Collisions */
99 #define ISMT_DESC_LPR 0x80 /* Large Packet Received */
102 #define ISMT_DESC_ADDR_RW(addr, rw) (((addr) << 1) | (rw))
104 /* iSMT General Register address offsets (SMBBAR + <addr>) */
105 #define ISMT_GR_GCTRL 0x000 /* General Control */
106 #define ISMT_GR_SMTICL 0x008 /* SMT Interrupt Cause Location */
107 #define ISMT_GR_ERRINTMSK 0x010 /* Error Interrupt Mask */
108 #define ISMT_GR_ERRAERMSK 0x014 /* Error AER Mask */
109 #define ISMT_GR_ERRSTS 0x018 /* Error Status */
110 #define ISMT_GR_ERRINFO 0x01c /* Error Information */
112 /* iSMT Master Registers */
113 #define ISMT_MSTR_MDBA 0x100 /* Master Descriptor Base Address */
114 #define ISMT_MSTR_MCTRL 0x108 /* Master Control */
115 #define ISMT_MSTR_MSTS 0x10c /* Master Status */
116 #define ISMT_MSTR_MDS 0x110 /* Master Descriptor Size */
117 #define ISMT_MSTR_RPOLICY 0x114 /* Retry Policy */
119 /* iSMT Miscellaneous Registers */
120 #define ISMT_SPGT 0x300 /* SMBus PHY Global Timing */
122 /* General Control Register (GCTRL) bit definitions */
123 #define ISMT_GCTRL_TRST 0x04 /* Target Reset */
124 #define ISMT_GCTRL_KILL 0x08 /* Kill */
125 #define ISMT_GCTRL_SRST 0x40 /* Soft Reset */
127 /* Master Control Register (MCTRL) bit definitions */
128 #define ISMT_MCTRL_SS 0x01 /* Start/Stop */
129 #define ISMT_MCTRL_MEIE 0x10 /* Master Error Interrupt Enable */
130 #define ISMT_MCTRL_FMHP 0x00ff0000 /* Firmware Master Head Ptr (FMHP) */
132 /* Master Status Register (MSTS) bit definitions */
133 #define ISMT_MSTS_HMTP 0xff0000 /* HW Master Tail Pointer (HMTP) */
134 #define ISMT_MSTS_MIS 0x20 /* Master Interrupt Status (MIS) */
135 #define ISMT_MSTS_MEIS 0x10 /* Master Error Int Status (MEIS) */
136 #define ISMT_MSTS_IP 0x01 /* In Progress */
138 /* Master Descriptor Size (MDS) bit definitions */
139 #define ISMT_MDS_MASK 0xff /* Master Descriptor Size mask (MDS) */
141 /* SMBus PHY Global Timing Register (SPGT) bit definitions */
142 #define ISMT_SPGT_SPD_MASK 0xc0000000 /* SMBus Speed mask */
143 #define ISMT_SPGT_SPD_80K 0x00 /* 80 kHz */
144 #define ISMT_SPGT_SPD_100K (0x1 << 30) /* 100 kHz */
145 #define ISMT_SPGT_SPD_400K (0x2 << 30) /* 400 kHz */
146 #define ISMT_SPGT_SPD_1M (0x3 << 30) /* 1 MHz */
149 /* MSI Control Register (MSICTL) bit definitions */
150 #define ISMT_MSICTL_MSIE 0x01 /* MSI Enable */
152 /* iSMT Hardware Descriptor */
154 u8 tgtaddr_rw
; /* target address & r/w bit */
155 u8 wr_len_cmd
; /* write length in bytes or a command */
156 u8 rd_len
; /* read length */
157 u8 control
; /* control bits */
158 u8 status
; /* status bits */
159 u8 retry
; /* collision retry and retry count */
160 u8 rxbytes
; /* received bytes */
161 u8 txbytes
; /* transmitted bytes */
162 u32 dptr_low
; /* lower 32 bit of the data pointer */
163 u32 dptr_high
; /* upper 32 bit of the data pointer */
167 struct i2c_adapter adapter
;
168 void __iomem
*smba
; /* PCI BAR */
169 struct pci_dev
*pci_dev
;
170 struct ismt_desc
*hw
; /* descriptor virt base addr */
171 dma_addr_t io_rng_dma
; /* descriptor HW base addr */
172 u8 head
; /* ring buffer head pointer */
173 struct completion cmp
; /* interrupt completion */
174 u8 dma_buffer
[I2C_SMBUS_BLOCK_MAX
+ 1]; /* temp R/W data buffer */
178 * ismt_ids - PCI device IDs supported by this driver
180 static const struct pci_device_id ismt_ids
[] = {
181 { PCI_DEVICE(PCI_VENDOR_ID_INTEL
, PCI_DEVICE_ID_INTEL_S1200_SMT0
) },
182 { PCI_DEVICE(PCI_VENDOR_ID_INTEL
, PCI_DEVICE_ID_INTEL_S1200_SMT1
) },
183 { PCI_DEVICE(PCI_VENDOR_ID_INTEL
, PCI_DEVICE_ID_INTEL_AVOTON_SMT
) },
187 MODULE_DEVICE_TABLE(pci
, ismt_ids
);
189 /* Bus speed control bits for slow debuggers - refer to the docs for usage */
190 static unsigned int bus_speed
;
191 module_param(bus_speed
, uint
, S_IRUGO
);
192 MODULE_PARM_DESC(bus_speed
, "Bus Speed in kHz (0 = BIOS default)");
195 * __ismt_desc_dump() - dump the contents of a specific descriptor
197 static void __ismt_desc_dump(struct device
*dev
, const struct ismt_desc
*desc
)
200 dev_dbg(dev
, "Descriptor struct: %p\n", desc
);
201 dev_dbg(dev
, "\ttgtaddr_rw=0x%02X\n", desc
->tgtaddr_rw
);
202 dev_dbg(dev
, "\twr_len_cmd=0x%02X\n", desc
->wr_len_cmd
);
203 dev_dbg(dev
, "\trd_len= 0x%02X\n", desc
->rd_len
);
204 dev_dbg(dev
, "\tcontrol= 0x%02X\n", desc
->control
);
205 dev_dbg(dev
, "\tstatus= 0x%02X\n", desc
->status
);
206 dev_dbg(dev
, "\tretry= 0x%02X\n", desc
->retry
);
207 dev_dbg(dev
, "\trxbytes= 0x%02X\n", desc
->rxbytes
);
208 dev_dbg(dev
, "\ttxbytes= 0x%02X\n", desc
->txbytes
);
209 dev_dbg(dev
, "\tdptr_low= 0x%08X\n", desc
->dptr_low
);
210 dev_dbg(dev
, "\tdptr_high= 0x%08X\n", desc
->dptr_high
);
213 * ismt_desc_dump() - dump the contents of a descriptor for debug purposes
214 * @priv: iSMT private data
216 static void ismt_desc_dump(struct ismt_priv
*priv
)
218 struct device
*dev
= &priv
->pci_dev
->dev
;
219 struct ismt_desc
*desc
= &priv
->hw
[priv
->head
];
221 dev_dbg(dev
, "Dump of the descriptor struct: 0x%X\n", priv
->head
);
222 __ismt_desc_dump(dev
, desc
);
226 * ismt_gen_reg_dump() - dump the iSMT General Registers
227 * @priv: iSMT private data
229 static void ismt_gen_reg_dump(struct ismt_priv
*priv
)
231 struct device
*dev
= &priv
->pci_dev
->dev
;
233 dev_dbg(dev
, "Dump of the iSMT General Registers\n");
234 dev_dbg(dev
, " GCTRL.... : (0x%p)=0x%X\n",
235 priv
->smba
+ ISMT_GR_GCTRL
,
236 readl(priv
->smba
+ ISMT_GR_GCTRL
));
237 dev_dbg(dev
, " SMTICL... : (0x%p)=0x%016llX\n",
238 priv
->smba
+ ISMT_GR_SMTICL
,
239 (long long unsigned int)readq(priv
->smba
+ ISMT_GR_SMTICL
));
240 dev_dbg(dev
, " ERRINTMSK : (0x%p)=0x%X\n",
241 priv
->smba
+ ISMT_GR_ERRINTMSK
,
242 readl(priv
->smba
+ ISMT_GR_ERRINTMSK
));
243 dev_dbg(dev
, " ERRAERMSK : (0x%p)=0x%X\n",
244 priv
->smba
+ ISMT_GR_ERRAERMSK
,
245 readl(priv
->smba
+ ISMT_GR_ERRAERMSK
));
246 dev_dbg(dev
, " ERRSTS... : (0x%p)=0x%X\n",
247 priv
->smba
+ ISMT_GR_ERRSTS
,
248 readl(priv
->smba
+ ISMT_GR_ERRSTS
));
249 dev_dbg(dev
, " ERRINFO.. : (0x%p)=0x%X\n",
250 priv
->smba
+ ISMT_GR_ERRINFO
,
251 readl(priv
->smba
+ ISMT_GR_ERRINFO
));
255 * ismt_mstr_reg_dump() - dump the iSMT Master Registers
256 * @priv: iSMT private data
258 static void ismt_mstr_reg_dump(struct ismt_priv
*priv
)
260 struct device
*dev
= &priv
->pci_dev
->dev
;
262 dev_dbg(dev
, "Dump of the iSMT Master Registers\n");
263 dev_dbg(dev
, " MDBA..... : (0x%p)=0x%016llX\n",
264 priv
->smba
+ ISMT_MSTR_MDBA
,
265 (long long unsigned int)readq(priv
->smba
+ ISMT_MSTR_MDBA
));
266 dev_dbg(dev
, " MCTRL.... : (0x%p)=0x%X\n",
267 priv
->smba
+ ISMT_MSTR_MCTRL
,
268 readl(priv
->smba
+ ISMT_MSTR_MCTRL
));
269 dev_dbg(dev
, " MSTS..... : (0x%p)=0x%X\n",
270 priv
->smba
+ ISMT_MSTR_MSTS
,
271 readl(priv
->smba
+ ISMT_MSTR_MSTS
));
272 dev_dbg(dev
, " MDS...... : (0x%p)=0x%X\n",
273 priv
->smba
+ ISMT_MSTR_MDS
,
274 readl(priv
->smba
+ ISMT_MSTR_MDS
));
275 dev_dbg(dev
, " RPOLICY.. : (0x%p)=0x%X\n",
276 priv
->smba
+ ISMT_MSTR_RPOLICY
,
277 readl(priv
->smba
+ ISMT_MSTR_RPOLICY
));
278 dev_dbg(dev
, " SPGT..... : (0x%p)=0x%X\n",
279 priv
->smba
+ ISMT_SPGT
,
280 readl(priv
->smba
+ ISMT_SPGT
));
284 * ismt_submit_desc() - add a descriptor to the ring
285 * @priv: iSMT private data
287 static void ismt_submit_desc(struct ismt_priv
*priv
)
292 ismt_desc_dump(priv
);
293 ismt_gen_reg_dump(priv
);
294 ismt_mstr_reg_dump(priv
);
296 /* Set the FMHP (Firmware Master Head Pointer)*/
297 fmhp
= ((priv
->head
+ 1) % ISMT_DESC_ENTRIES
) << 16;
298 val
= readl(priv
->smba
+ ISMT_MSTR_MCTRL
);
299 writel((val
& ~ISMT_MCTRL_FMHP
) | fmhp
,
300 priv
->smba
+ ISMT_MSTR_MCTRL
);
302 /* Set the start bit */
303 val
= readl(priv
->smba
+ ISMT_MSTR_MCTRL
);
304 writel(val
| ISMT_MCTRL_SS
,
305 priv
->smba
+ ISMT_MSTR_MCTRL
);
309 * ismt_process_desc() - handle the completion of the descriptor
310 * @desc: the iSMT hardware descriptor
311 * @data: data buffer from the upper layer
312 * @priv: ismt_priv struct holding our dma buffer
313 * @size: SMBus transaction type
314 * @read_write: flag to indicate if this is a read or write
316 static int ismt_process_desc(const struct ismt_desc
*desc
,
317 union i2c_smbus_data
*data
,
318 struct ismt_priv
*priv
, int size
,
321 u8
*dma_buffer
= priv
->dma_buffer
;
323 dev_dbg(&priv
->pci_dev
->dev
, "Processing completed descriptor\n");
324 __ismt_desc_dump(&priv
->pci_dev
->dev
, desc
);
326 if (desc
->status
& ISMT_DESC_SCS
) {
327 if (read_write
== I2C_SMBUS_WRITE
&&
328 size
!= I2C_SMBUS_PROC_CALL
)
333 case I2C_SMBUS_BYTE_DATA
:
334 data
->byte
= dma_buffer
[0];
336 case I2C_SMBUS_WORD_DATA
:
337 case I2C_SMBUS_PROC_CALL
:
338 data
->word
= dma_buffer
[0] | (dma_buffer
[1] << 8);
340 case I2C_SMBUS_BLOCK_DATA
:
341 case I2C_SMBUS_I2C_BLOCK_DATA
:
342 memcpy(&data
->block
[1], dma_buffer
, desc
->rxbytes
);
343 data
->block
[0] = desc
->rxbytes
;
349 if (likely(desc
->status
& ISMT_DESC_NAK
))
352 if (desc
->status
& ISMT_DESC_CRC
)
355 if (desc
->status
& ISMT_DESC_COL
)
358 if (desc
->status
& ISMT_DESC_LPR
)
361 if (desc
->status
& (ISMT_DESC_DLTO
| ISMT_DESC_CLTO
))
368 * ismt_access() - process an SMBus command
369 * @adap: the i2c host adapter
370 * @addr: address of the i2c/SMBus target
371 * @flags: command options
372 * @read_write: read from or write to device
373 * @command: the i2c/SMBus command to issue
374 * @size: SMBus transaction type
375 * @data: read/write data buffer
377 static int ismt_access(struct i2c_adapter
*adap
, u16 addr
,
378 unsigned short flags
, char read_write
, u8 command
,
379 int size
, union i2c_smbus_data
*data
)
382 unsigned long time_left
;
383 dma_addr_t dma_addr
= 0; /* address of the data buffer */
385 enum dma_data_direction dma_direction
= 0;
386 struct ismt_desc
*desc
;
387 struct ismt_priv
*priv
= i2c_get_adapdata(adap
);
388 struct device
*dev
= &priv
->pci_dev
->dev
;
390 desc
= &priv
->hw
[priv
->head
];
392 /* Initialize the DMA buffer */
393 memset(priv
->dma_buffer
, 0, sizeof(priv
->dma_buffer
));
395 /* Initialize the descriptor */
396 memset(desc
, 0, sizeof(struct ismt_desc
));
397 desc
->tgtaddr_rw
= ISMT_DESC_ADDR_RW(addr
, read_write
);
399 /* Initialize common control bits */
400 if (likely(pci_dev_msi_enabled(priv
->pci_dev
)))
401 desc
->control
= ISMT_DESC_INT
| ISMT_DESC_FAIR
;
403 desc
->control
= ISMT_DESC_FAIR
;
405 if ((flags
& I2C_CLIENT_PEC
) && (size
!= I2C_SMBUS_QUICK
)
406 && (size
!= I2C_SMBUS_I2C_BLOCK_DATA
))
407 desc
->control
|= ISMT_DESC_PEC
;
410 case I2C_SMBUS_QUICK
:
411 dev_dbg(dev
, "I2C_SMBUS_QUICK\n");
415 if (read_write
== I2C_SMBUS_WRITE
) {
418 * The command field contains the write data
420 dev_dbg(dev
, "I2C_SMBUS_BYTE: WRITE\n");
421 desc
->control
|= ISMT_DESC_CWRL
;
422 desc
->wr_len_cmd
= command
;
425 dev_dbg(dev
, "I2C_SMBUS_BYTE: READ\n");
427 dma_direction
= DMA_FROM_DEVICE
;
432 case I2C_SMBUS_BYTE_DATA
:
433 if (read_write
== I2C_SMBUS_WRITE
) {
436 * Command plus 1 data byte
438 dev_dbg(dev
, "I2C_SMBUS_BYTE_DATA: WRITE\n");
439 desc
->wr_len_cmd
= 2;
441 dma_direction
= DMA_TO_DEVICE
;
442 priv
->dma_buffer
[0] = command
;
443 priv
->dma_buffer
[1] = data
->byte
;
446 dev_dbg(dev
, "I2C_SMBUS_BYTE_DATA: READ\n");
447 desc
->control
|= ISMT_DESC_CWRL
;
448 desc
->wr_len_cmd
= command
;
451 dma_direction
= DMA_FROM_DEVICE
;
455 case I2C_SMBUS_WORD_DATA
:
456 if (read_write
== I2C_SMBUS_WRITE
) {
458 dev_dbg(dev
, "I2C_SMBUS_WORD_DATA: WRITE\n");
459 desc
->wr_len_cmd
= 3;
461 dma_direction
= DMA_TO_DEVICE
;
462 priv
->dma_buffer
[0] = command
;
463 priv
->dma_buffer
[1] = data
->word
& 0xff;
464 priv
->dma_buffer
[2] = data
->word
>> 8;
467 dev_dbg(dev
, "I2C_SMBUS_WORD_DATA: READ\n");
468 desc
->wr_len_cmd
= command
;
469 desc
->control
|= ISMT_DESC_CWRL
;
472 dma_direction
= DMA_FROM_DEVICE
;
476 case I2C_SMBUS_PROC_CALL
:
477 dev_dbg(dev
, "I2C_SMBUS_PROC_CALL\n");
478 desc
->wr_len_cmd
= 3;
481 dma_direction
= DMA_BIDIRECTIONAL
;
482 priv
->dma_buffer
[0] = command
;
483 priv
->dma_buffer
[1] = data
->word
& 0xff;
484 priv
->dma_buffer
[2] = data
->word
>> 8;
487 case I2C_SMBUS_BLOCK_DATA
:
488 if (read_write
== I2C_SMBUS_WRITE
) {
490 dev_dbg(dev
, "I2C_SMBUS_BLOCK_DATA: WRITE\n");
491 dma_size
= data
->block
[0] + 1;
492 dma_direction
= DMA_TO_DEVICE
;
493 desc
->wr_len_cmd
= dma_size
;
494 desc
->control
|= ISMT_DESC_BLK
;
495 priv
->dma_buffer
[0] = command
;
496 memcpy(&priv
->dma_buffer
[1], &data
->block
[1], dma_size
- 1);
499 dev_dbg(dev
, "I2C_SMBUS_BLOCK_DATA: READ\n");
500 dma_size
= I2C_SMBUS_BLOCK_MAX
;
501 dma_direction
= DMA_FROM_DEVICE
;
502 desc
->rd_len
= dma_size
;
503 desc
->wr_len_cmd
= command
;
504 desc
->control
|= (ISMT_DESC_BLK
| ISMT_DESC_CWRL
);
508 case I2C_SMBUS_I2C_BLOCK_DATA
:
509 /* Make sure the length is valid */
510 if (data
->block
[0] < 1)
513 if (data
->block
[0] > I2C_SMBUS_BLOCK_MAX
)
514 data
->block
[0] = I2C_SMBUS_BLOCK_MAX
;
516 if (read_write
== I2C_SMBUS_WRITE
) {
517 /* i2c Block Write */
518 dev_dbg(dev
, "I2C_SMBUS_I2C_BLOCK_DATA: WRITE\n");
519 dma_size
= data
->block
[0] + 1;
520 dma_direction
= DMA_TO_DEVICE
;
521 desc
->wr_len_cmd
= dma_size
;
522 desc
->control
|= ISMT_DESC_I2C
;
523 priv
->dma_buffer
[0] = command
;
524 memcpy(&priv
->dma_buffer
[1], &data
->block
[1], dma_size
- 1);
527 dev_dbg(dev
, "I2C_SMBUS_I2C_BLOCK_DATA: READ\n");
528 dma_size
= data
->block
[0];
529 dma_direction
= DMA_FROM_DEVICE
;
530 desc
->rd_len
= dma_size
;
531 desc
->wr_len_cmd
= command
;
532 desc
->control
|= (ISMT_DESC_I2C
| ISMT_DESC_CWRL
);
534 * Per the "Table 15-15. I2C Commands",
535 * in the External Design Specification (EDS),
536 * (Document Number: 508084, Revision: 2.0),
537 * the _rw bit must be 0
539 desc
->tgtaddr_rw
= ISMT_DESC_ADDR_RW(addr
, 0);
544 dev_err(dev
, "Unsupported transaction %d\n",
549 /* map the data buffer */
551 dev_dbg(dev
, " dev=%p\n", dev
);
552 dev_dbg(dev
, " data=%p\n", data
);
553 dev_dbg(dev
, " dma_buffer=%p\n", priv
->dma_buffer
);
554 dev_dbg(dev
, " dma_size=%d\n", dma_size
);
555 dev_dbg(dev
, " dma_direction=%d\n", dma_direction
);
557 dma_addr
= dma_map_single(dev
,
562 if (dma_mapping_error(dev
, dma_addr
)) {
563 dev_err(dev
, "Error in mapping dma buffer %p\n",
568 dev_dbg(dev
, " dma_addr = 0x%016llX\n",
569 (unsigned long long)dma_addr
);
571 desc
->dptr_low
= lower_32_bits(dma_addr
);
572 desc
->dptr_high
= upper_32_bits(dma_addr
);
575 reinit_completion(&priv
->cmp
);
577 /* Add the descriptor */
578 ismt_submit_desc(priv
);
580 /* Now we wait for interrupt completion, 1s */
581 time_left
= wait_for_completion_timeout(&priv
->cmp
, HZ
*1);
583 /* unmap the data buffer */
585 dma_unmap_single(&adap
->dev
, dma_addr
, dma_size
, dma_direction
);
587 if (unlikely(!time_left
)) {
588 dev_err(dev
, "completion wait timed out\n");
593 /* do any post processing of the descriptor here */
594 ret
= ismt_process_desc(desc
, data
, priv
, size
, read_write
);
597 /* Update the ring pointer */
599 priv
->head
%= ISMT_DESC_ENTRIES
;
605 * ismt_func() - report which i2c commands are supported by this adapter
606 * @adap: the i2c host adapter
608 static u32
ismt_func(struct i2c_adapter
*adap
)
610 return I2C_FUNC_SMBUS_QUICK
|
611 I2C_FUNC_SMBUS_BYTE
|
612 I2C_FUNC_SMBUS_BYTE_DATA
|
613 I2C_FUNC_SMBUS_WORD_DATA
|
614 I2C_FUNC_SMBUS_PROC_CALL
|
615 I2C_FUNC_SMBUS_BLOCK_DATA
|
616 I2C_FUNC_SMBUS_I2C_BLOCK
|
621 * smbus_algorithm - the adapter algorithm and supported functionality
622 * @smbus_xfer: the adapter algorithm
623 * @functionality: functionality supported by the adapter
625 static const struct i2c_algorithm smbus_algorithm
= {
626 .smbus_xfer
= ismt_access
,
627 .functionality
= ismt_func
,
631 * ismt_handle_isr() - interrupt handler bottom half
632 * @priv: iSMT private data
634 static irqreturn_t
ismt_handle_isr(struct ismt_priv
*priv
)
636 complete(&priv
->cmp
);
643 * ismt_do_interrupt() - IRQ interrupt handler
644 * @vec: interrupt vector
645 * @data: iSMT private data
647 static irqreturn_t
ismt_do_interrupt(int vec
, void *data
)
650 struct ismt_priv
*priv
= data
;
653 * check to see it's our interrupt, return IRQ_NONE if not ours
654 * since we are sharing interrupt
656 val
= readl(priv
->smba
+ ISMT_MSTR_MSTS
);
658 if (!(val
& (ISMT_MSTS_MIS
| ISMT_MSTS_MEIS
)))
661 writel(val
| ISMT_MSTS_MIS
| ISMT_MSTS_MEIS
,
662 priv
->smba
+ ISMT_MSTR_MSTS
);
664 return ismt_handle_isr(priv
);
668 * ismt_do_msi_interrupt() - MSI interrupt handler
669 * @vec: interrupt vector
670 * @data: iSMT private data
672 static irqreturn_t
ismt_do_msi_interrupt(int vec
, void *data
)
674 return ismt_handle_isr(data
);
678 * ismt_hw_init() - initialize the iSMT hardware
679 * @priv: iSMT private data
681 static void ismt_hw_init(struct ismt_priv
*priv
)
684 struct device
*dev
= &priv
->pci_dev
->dev
;
686 /* initialize the Master Descriptor Base Address (MDBA) */
687 writeq(priv
->io_rng_dma
, priv
->smba
+ ISMT_MSTR_MDBA
);
689 /* initialize the Master Control Register (MCTRL) */
690 writel(ISMT_MCTRL_MEIE
, priv
->smba
+ ISMT_MSTR_MCTRL
);
692 /* initialize the Master Status Register (MSTS) */
693 writel(0, priv
->smba
+ ISMT_MSTR_MSTS
);
695 /* initialize the Master Descriptor Size (MDS) */
696 val
= readl(priv
->smba
+ ISMT_MSTR_MDS
);
697 writel((val
& ~ISMT_MDS_MASK
) | (ISMT_DESC_ENTRIES
- 1),
698 priv
->smba
+ ISMT_MSTR_MDS
);
701 * Set the SMBus speed (could use this for slow HW debuggers)
704 val
= readl(priv
->smba
+ ISMT_SPGT
);
711 dev_dbg(dev
, "Setting SMBus clock to 80 kHz\n");
712 writel(((val
& ~ISMT_SPGT_SPD_MASK
) | ISMT_SPGT_SPD_80K
),
713 priv
->smba
+ ISMT_SPGT
);
717 dev_dbg(dev
, "Setting SMBus clock to 100 kHz\n");
718 writel(((val
& ~ISMT_SPGT_SPD_MASK
) | ISMT_SPGT_SPD_100K
),
719 priv
->smba
+ ISMT_SPGT
);
723 dev_dbg(dev
, "Setting SMBus clock to 400 kHz\n");
724 writel(((val
& ~ISMT_SPGT_SPD_MASK
) | ISMT_SPGT_SPD_400K
),
725 priv
->smba
+ ISMT_SPGT
);
729 dev_dbg(dev
, "Setting SMBus clock to 1000 kHz\n");
730 writel(((val
& ~ISMT_SPGT_SPD_MASK
) | ISMT_SPGT_SPD_1M
),
731 priv
->smba
+ ISMT_SPGT
);
735 dev_warn(dev
, "Invalid SMBus clock speed, only 0, 80, 100, 400, and 1000 are valid\n");
739 val
= readl(priv
->smba
+ ISMT_SPGT
);
741 switch (val
& ISMT_SPGT_SPD_MASK
) {
742 case ISMT_SPGT_SPD_80K
:
745 case ISMT_SPGT_SPD_100K
:
748 case ISMT_SPGT_SPD_400K
:
751 case ISMT_SPGT_SPD_1M
:
755 dev_dbg(dev
, "SMBus clock is running at %d kHz\n", bus_speed
);
759 * ismt_dev_init() - initialize the iSMT data structures
760 * @priv: iSMT private data
762 static int ismt_dev_init(struct ismt_priv
*priv
)
764 /* allocate memory for the descriptor */
765 priv
->hw
= dmam_alloc_coherent(&priv
->pci_dev
->dev
,
767 * sizeof(struct ismt_desc
)),
773 memset(priv
->hw
, 0, (ISMT_DESC_ENTRIES
* sizeof(struct ismt_desc
)));
776 init_completion(&priv
->cmp
);
782 * ismt_int_init() - initialize interrupts
783 * @priv: iSMT private data
785 static int ismt_int_init(struct ismt_priv
*priv
)
789 /* Try using MSI interrupts */
790 err
= pci_enable_msi(priv
->pci_dev
);
794 err
= devm_request_irq(&priv
->pci_dev
->dev
,
796 ismt_do_msi_interrupt
,
801 pci_disable_msi(priv
->pci_dev
);
807 /* Try using legacy interrupts */
809 dev_warn(&priv
->pci_dev
->dev
,
810 "Unable to use MSI interrupts, falling back to legacy\n");
812 err
= devm_request_irq(&priv
->pci_dev
->dev
,
819 dev_err(&priv
->pci_dev
->dev
, "no usable interrupts\n");
826 static struct pci_driver ismt_driver
;
829 * ismt_probe() - probe for iSMT devices
830 * @pdev: PCI-Express device
831 * @id: PCI-Express device ID
834 ismt_probe(struct pci_dev
*pdev
, const struct pci_device_id
*id
)
837 struct ismt_priv
*priv
;
838 unsigned long start
, len
;
840 priv
= devm_kzalloc(&pdev
->dev
, sizeof(*priv
), GFP_KERNEL
);
844 pci_set_drvdata(pdev
, priv
);
846 i2c_set_adapdata(&priv
->adapter
, priv
);
847 priv
->adapter
.owner
= THIS_MODULE
;
848 priv
->adapter
.class = I2C_CLASS_HWMON
;
849 priv
->adapter
.algo
= &smbus_algorithm
;
850 priv
->adapter
.dev
.parent
= &pdev
->dev
;
851 ACPI_COMPANION_SET(&priv
->adapter
.dev
, ACPI_COMPANION(&pdev
->dev
));
852 priv
->adapter
.retries
= ISMT_MAX_RETRIES
;
854 priv
->pci_dev
= pdev
;
856 err
= pcim_enable_device(pdev
);
858 dev_err(&pdev
->dev
, "Failed to enable SMBus PCI device (%d)\n",
863 /* enable bus mastering */
864 pci_set_master(pdev
);
866 /* Determine the address of the SMBus area */
867 start
= pci_resource_start(pdev
, SMBBAR
);
868 len
= pci_resource_len(pdev
, SMBBAR
);
869 if (!start
|| !len
) {
871 "SMBus base address uninitialized, upgrade BIOS\n");
875 snprintf(priv
->adapter
.name
, sizeof(priv
->adapter
.name
),
876 "SMBus iSMT adapter at %lx", start
);
878 dev_dbg(&priv
->pci_dev
->dev
, " start=0x%lX\n", start
);
879 dev_dbg(&priv
->pci_dev
->dev
, " len=0x%lX\n", len
);
881 err
= acpi_check_resource_conflict(&pdev
->resource
[SMBBAR
]);
883 dev_err(&pdev
->dev
, "ACPI resource conflict!\n");
887 err
= pci_request_region(pdev
, SMBBAR
, ismt_driver
.name
);
890 "Failed to request SMBus region 0x%lx-0x%lx\n",
895 priv
->smba
= pcim_iomap(pdev
, SMBBAR
, len
);
897 dev_err(&pdev
->dev
, "Unable to ioremap SMBus BAR\n");
901 if ((pci_set_dma_mask(pdev
, DMA_BIT_MASK(64)) != 0) ||
902 (pci_set_consistent_dma_mask(pdev
, DMA_BIT_MASK(64)) != 0)) {
903 if ((pci_set_dma_mask(pdev
, DMA_BIT_MASK(32)) != 0) ||
904 (pci_set_consistent_dma_mask(pdev
,
905 DMA_BIT_MASK(32)) != 0)) {
906 dev_err(&pdev
->dev
, "pci_set_dma_mask fail %p\n",
912 err
= ismt_dev_init(priv
);
918 err
= ismt_int_init(priv
);
922 err
= i2c_add_adapter(&priv
->adapter
);
924 dev_err(&pdev
->dev
, "Failed to add SMBus iSMT adapter\n");
931 * ismt_remove() - release driver resources
932 * @pdev: PCI-Express device
934 static void ismt_remove(struct pci_dev
*pdev
)
936 struct ismt_priv
*priv
= pci_get_drvdata(pdev
);
938 i2c_del_adapter(&priv
->adapter
);
941 static struct pci_driver ismt_driver
= {
942 .name
= "ismt_smbus",
943 .id_table
= ismt_ids
,
945 .remove
= ismt_remove
,
948 module_pci_driver(ismt_driver
);
950 MODULE_LICENSE("Dual BSD/GPL");
951 MODULE_AUTHOR("Bill E. Brown <bill.e.brown@intel.com>");
952 MODULE_DESCRIPTION("Intel SMBus Message Transport (iSMT) driver");