projects / deliverable / linux.git / blame
? search:
summary | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Linux 4.3-rc4
[deliverable/linux.git] / drivers / i2c / busses / i2c-ismt.c
CommitLineData
13f35ac1
NH		 1/*
2 * This file is provided under a dual BSD/GPLv2 license. When using or
3 * redistributing this file, you may do so under either license.
4 *
5 * Copyright(c) 2012 Intel Corporation. All rights reserved.
6 *
7 * GPL LICENSE SUMMARY
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of version 2 of the GNU General Public License as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
13f35ac1
NH		 17 * The full GNU General Public License is included in this distribution
18 * in the file called LICENSE.GPL.
19 *
20 * BSD LICENSE
21 *
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
24 * are met:
25 *
26 * * Redistributions of source code must retain the above copyright
27 * notice, this list of conditions and the following disclaimer.
28 * * Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in
30 * the documentation and/or other materials provided with the
31 * distribution.
32 * * Neither the name of Intel Corporation nor the names of its
33 * contributors may be used to endorse or promote products derived
34 * from this software without specific prior written permission.
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
37 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
38 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
39 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
40 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
42 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
43 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
44 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
45 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
46 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
47 */
48
49/*
50 * Supports the SMBus Message Transport (SMT) in the Intel Atom Processor
51 * S12xx Product Family.
52 *
53 * Features supported by this driver:
54 * Hardware PEC yes
55 * Block buffer yes
56 * Block process call transaction no
57 * Slave mode no
58 */
59
60#include <linux/module.h>
13f35ac1
NH		 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>
69
70#include <asm-generic/io-64-nonatomic-lo-hi.h>
71
72/* PCI Address Constants */
73#define SMBBAR 0
74
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
488b9269 78#define PCI_DEVICE_ID_INTEL_AVOTON_SMT 0x1f15
13f35ac1 79
8b57cebe 80#define ISMT_DESC_ENTRIES 2 /* number of descriptor entries */
13f35ac1
NH		 81#define ISMT_MAX_RETRIES 3 /* number of SMBus retries to attempt */
82
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 */
91
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 */
100
101/* Macros */
102#define ISMT_DESC_ADDR_RW(addr, rw) (((addr) << 1) | (rw))
103
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 */
111
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 */
118
119/* iSMT Miscellaneous Registers */
120#define ISMT_SPGT 0x300 /* SMBus PHY Global Timing */
121
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 */
126
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) */
131
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 */
137
138/* Master Descriptor Size (MDS) bit definitions */
139#define ISMT_MDS_MASK 0xff /* Master Descriptor Size mask (MDS) */
140
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 */
147
148
149/* MSI Control Register (MSICTL) bit definitions */
150#define ISMT_MSICTL_MSIE 0x01 /* MSI Enable */
151
152/* iSMT Hardware Descriptor */
153struct ismt_desc {
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 */
164} __packed;
165
166struct ismt_priv {
167 struct i2c_adapter adapter;
168 void *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 */
175 bool using_msi; /* type of interrupt flag */
176};
177
178/**
179 * ismt_ids - PCI device IDs supported by this driver
180 */
392debf1 181static const struct pci_device_id ismt_ids[] = {
13f35ac1
NH		 182 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT0) },
183 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_S1200_SMT1) },
488b9269 184 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMT) },
13f35ac1
NH		 185 { 0, }
186};
187
188MODULE_DEVICE_TABLE(pci, ismt_ids);
189
190/* Bus speed control bits for slow debuggers - refer to the docs for usage */
191static unsigned int bus_speed;
192module_param(bus_speed, uint, S_IRUGO);
193MODULE_PARM_DESC(bus_speed, "Bus Speed in kHz (0 = BIOS default)");
194
195/**
196 * __ismt_desc_dump() - dump the contents of a specific descriptor
197 */
198static void __ismt_desc_dump(struct device *dev, const struct ismt_desc *desc)
199{
200
201 dev_dbg(dev, "Descriptor struct: %p\n", desc);
202 dev_dbg(dev, "\ttgtaddr_rw=0x%02X\n", desc->tgtaddr_rw);
203 dev_dbg(dev, "\twr_len_cmd=0x%02X\n", desc->wr_len_cmd);
204 dev_dbg(dev, "\trd_len= 0x%02X\n", desc->rd_len);
205 dev_dbg(dev, "\tcontrol= 0x%02X\n", desc->control);
206 dev_dbg(dev, "\tstatus= 0x%02X\n", desc->status);
207 dev_dbg(dev, "\tretry= 0x%02X\n", desc->retry);
208 dev_dbg(dev, "\trxbytes= 0x%02X\n", desc->rxbytes);
209 dev_dbg(dev, "\ttxbytes= 0x%02X\n", desc->txbytes);
210 dev_dbg(dev, "\tdptr_low= 0x%08X\n", desc->dptr_low);
211 dev_dbg(dev, "\tdptr_high= 0x%08X\n", desc->dptr_high);
212}
213/**
214 * ismt_desc_dump() - dump the contents of a descriptor for debug purposes
215 * @priv: iSMT private data
216 */
217static void ismt_desc_dump(struct ismt_priv *priv)
218{
219 struct device *dev = &priv->pci_dev->dev;
220 struct ismt_desc *desc = &priv->hw[priv->head];
221
222 dev_dbg(dev, "Dump of the descriptor struct: 0x%X\n", priv->head);
223 __ismt_desc_dump(dev, desc);
224}
225
226/**
227 * ismt_gen_reg_dump() - dump the iSMT General Registers
228 * @priv: iSMT private data
229 */
230static void ismt_gen_reg_dump(struct ismt_priv *priv)
231{
232 struct device *dev = &priv->pci_dev->dev;
233
234 dev_dbg(dev, "Dump of the iSMT General Registers\n");
235 dev_dbg(dev, " GCTRL.... : (0x%p)=0x%X\n",
236 priv->smba + ISMT_GR_GCTRL,
237 readl(priv->smba + ISMT_GR_GCTRL));
238 dev_dbg(dev, " SMTICL... : (0x%p)=0x%016llX\n",
239 priv->smba + ISMT_GR_SMTICL,
240 (long long unsigned int)readq(priv->smba + ISMT_GR_SMTICL));
241 dev_dbg(dev, " ERRINTMSK : (0x%p)=0x%X\n",
242 priv->smba + ISMT_GR_ERRINTMSK,
243 readl(priv->smba + ISMT_GR_ERRINTMSK));
244 dev_dbg(dev, " ERRAERMSK : (0x%p)=0x%X\n",
245 priv->smba + ISMT_GR_ERRAERMSK,
246 readl(priv->smba + ISMT_GR_ERRAERMSK));
247 dev_dbg(dev, " ERRSTS... : (0x%p)=0x%X\n",
248 priv->smba + ISMT_GR_ERRSTS,
249 readl(priv->smba + ISMT_GR_ERRSTS));
250 dev_dbg(dev, " ERRINFO.. : (0x%p)=0x%X\n",
251 priv->smba + ISMT_GR_ERRINFO,
252 readl(priv->smba + ISMT_GR_ERRINFO));
253}
254
255/**
256 * ismt_mstr_reg_dump() - dump the iSMT Master Registers
257 * @priv: iSMT private data
258 */
259static void ismt_mstr_reg_dump(struct ismt_priv *priv)
260{
261 struct device *dev = &priv->pci_dev->dev;
262
263 dev_dbg(dev, "Dump of the iSMT Master Registers\n");
264 dev_dbg(dev, " MDBA..... : (0x%p)=0x%016llX\n",
265 priv->smba + ISMT_MSTR_MDBA,
266 (long long unsigned int)readq(priv->smba + ISMT_MSTR_MDBA));
267 dev_dbg(dev, " MCTRL.... : (0x%p)=0x%X\n",
268 priv->smba + ISMT_MSTR_MCTRL,
269 readl(priv->smba + ISMT_MSTR_MCTRL));
270 dev_dbg(dev, " MSTS..... : (0x%p)=0x%X\n",
271 priv->smba + ISMT_MSTR_MSTS,
272 readl(priv->smba + ISMT_MSTR_MSTS));
273 dev_dbg(dev, " MDS...... : (0x%p)=0x%X\n",
274 priv->smba + ISMT_MSTR_MDS,
275 readl(priv->smba + ISMT_MSTR_MDS));
276 dev_dbg(dev, " RPOLICY.. : (0x%p)=0x%X\n",
277 priv->smba + ISMT_MSTR_RPOLICY,
278 readl(priv->smba + ISMT_MSTR_RPOLICY));
279 dev_dbg(dev, " SPGT..... : (0x%p)=0x%X\n",
280 priv->smba + ISMT_SPGT,
281 readl(priv->smba + ISMT_SPGT));
282}
283
284/**
285 * ismt_submit_desc() - add a descriptor to the ring
286 * @priv: iSMT private data
287 */
288static void ismt_submit_desc(struct ismt_priv *priv)
289{
290 uint fmhp;
291 uint val;
292
293 ismt_desc_dump(priv);
294 ismt_gen_reg_dump(priv);
295 ismt_mstr_reg_dump(priv);
296
297 /* Set the FMHP (Firmware Master Head Pointer)*/
298 fmhp = ((priv->head + 1) % ISMT_DESC_ENTRIES) << 16;
299 val = readl(priv->smba + ISMT_MSTR_MCTRL);
300 writel((val & ~ISMT_MCTRL_FMHP) | fmhp,
301 priv->smba + ISMT_MSTR_MCTRL);
302
303 /* Set the start bit */
304 val = readl(priv->smba + ISMT_MSTR_MCTRL);
305 writel(val | ISMT_MCTRL_SS,
306 priv->smba + ISMT_MSTR_MCTRL);
307}
308
309/**
310 * ismt_process_desc() - handle the completion of the descriptor
311 * @desc: the iSMT hardware descriptor
312 * @data: data buffer from the upper layer
313 * @priv: ismt_priv struct holding our dma buffer
314 * @size: SMBus transaction type
315 * @read_write: flag to indicate if this is a read or write
316 */
317static int ismt_process_desc(const struct ismt_desc *desc,
318 union i2c_smbus_data *data,
319 struct ismt_priv *priv, int size,
320 char read_write)
321{
322 u8 *dma_buffer = priv->dma_buffer;
323
324 dev_dbg(&priv->pci_dev->dev, "Processing completed descriptor\n");
325 __ismt_desc_dump(&priv->pci_dev->dev, desc);
326
327 if (desc->status & ISMT_DESC_SCS) {
328 if (read_write == I2C_SMBUS_WRITE &&
329 size != I2C_SMBUS_PROC_CALL)
330 return 0;
331
332 switch (size) {
333 case I2C_SMBUS_BYTE:
334 case I2C_SMBUS_BYTE_DATA:
335 data->byte = dma_buffer[0];
336 break;
337 case I2C_SMBUS_WORD_DATA:
338 case I2C_SMBUS_PROC_CALL:
339 data->word = dma_buffer[0] | (dma_buffer[1] << 8);
340 break;
341 case I2C_SMBUS_BLOCK_DATA:
001cebf0 342 case I2C_SMBUS_I2C_BLOCK_DATA:
13f35ac1
NH		 343 memcpy(&data->block[1], dma_buffer, desc->rxbytes);
344 data->block[0] = desc->rxbytes;
345 break;
346 }
347 return 0;
348 }
349
350 if (likely(desc->status & ISMT_DESC_NAK))
351 return -ENXIO;
352
353 if (desc->status & ISMT_DESC_CRC)
354 return -EBADMSG;
355
356 if (desc->status & ISMT_DESC_COL)
357 return -EAGAIN;
358
359 if (desc->status & ISMT_DESC_LPR)
360 return -EPROTO;
361
362 if (desc->status & (ISMT_DESC_DLTO | ISMT_DESC_CLTO))
363 return -ETIMEDOUT;
364
365 return -EIO;
366}
367
368/**
369 * ismt_access() - process an SMBus command
370 * @adap: the i2c host adapter
371 * @addr: address of the i2c/SMBus target
372 * @flags: command options
373 * @read_write: read from or write to device
374 * @command: the i2c/SMBus command to issue
375 * @size: SMBus transaction type
376 * @data: read/write data buffer
377 */
378static int ismt_access(struct i2c_adapter *adap, u16 addr,
379 unsigned short flags, char read_write, u8 command,
380 int size, union i2c_smbus_data *data)
381{
382 int ret;
1abdd5d9 383 unsigned long time_left;
13f35ac1
NH		 384 dma_addr_t dma_addr = 0; /* address of the data buffer */
385 u8 dma_size = 0;
386 enum dma_data_direction dma_direction = 0;
387 struct ismt_desc *desc;
388 struct ismt_priv *priv = i2c_get_adapdata(adap);
389 struct device *dev = &priv->pci_dev->dev;
390
391 desc = &priv->hw[priv->head];
bf416910
JR		 392
393 /* Initialize the DMA buffer */
394 memset(priv->dma_buffer, 0, sizeof(priv->dma_buffer));
13f35ac1
NH		 395
396 /* Initialize the descriptor */
397 memset(desc, 0, sizeof(struct ismt_desc));
398 desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, read_write);
399
400 /* Initialize common control bits */
401 if (likely(priv->using_msi))
402 desc->control = ISMT_DESC_INT | ISMT_DESC_FAIR;
403 else
404 desc->control = ISMT_DESC_FAIR;
405
406 if ((flags & I2C_CLIENT_PEC) && (size != I2C_SMBUS_QUICK)
407 && (size != I2C_SMBUS_I2C_BLOCK_DATA))
408 desc->control |= ISMT_DESC_PEC;
409
410 switch (size) {
411 case I2C_SMBUS_QUICK:
412 dev_dbg(dev, "I2C_SMBUS_QUICK\n");
413 break;
414
415 case I2C_SMBUS_BYTE:
416 if (read_write == I2C_SMBUS_WRITE) {
417 /*
418 * Send Byte
419 * The command field contains the write data
420 */
421 dev_dbg(dev, "I2C_SMBUS_BYTE: WRITE\n");
422 desc->control |= ISMT_DESC_CWRL;
423 desc->wr_len_cmd = command;
424 } else {
425 /* Receive Byte */
426 dev_dbg(dev, "I2C_SMBUS_BYTE: READ\n");
427 dma_size = 1;
428 dma_direction = DMA_FROM_DEVICE;
429 desc->rd_len = 1;
430 }
431 break;
432
433 case I2C_SMBUS_BYTE_DATA:
434 if (read_write == I2C_SMBUS_WRITE) {
435 /*
436 * Write Byte
437 * Command plus 1 data byte
438 */
439 dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: WRITE\n");
440 desc->wr_len_cmd = 2;
441 dma_size = 2;
442 dma_direction = DMA_TO_DEVICE;
443 priv->dma_buffer[0] = command;
444 priv->dma_buffer[1] = data->byte;
445 } else {
446 /* Read Byte */
447 dev_dbg(dev, "I2C_SMBUS_BYTE_DATA: READ\n");
448 desc->control |= ISMT_DESC_CWRL;
449 desc->wr_len_cmd = command;
450 desc->rd_len = 1;
451 dma_size = 1;
452 dma_direction = DMA_FROM_DEVICE;
453 }
454 break;
455
456 case I2C_SMBUS_WORD_DATA:
457 if (read_write == I2C_SMBUS_WRITE) {
458 /* Write Word */
459 dev_dbg(dev, "I2C_SMBUS_WORD_DATA: WRITE\n");
460 desc->wr_len_cmd = 3;
461 dma_size = 3;
462 dma_direction = DMA_TO_DEVICE;
463 priv->dma_buffer[0] = command;
464 priv->dma_buffer[1] = data->word & 0xff;
465 priv->dma_buffer[2] = data->word >> 8;
466 } else {
467 /* Read Word */
468 dev_dbg(dev, "I2C_SMBUS_WORD_DATA: READ\n");
469 desc->wr_len_cmd = command;
470 desc->control |= ISMT_DESC_CWRL;
471 desc->rd_len = 2;
472 dma_size = 2;
473 dma_direction = DMA_FROM_DEVICE;
474 }
475 break;
476
477 case I2C_SMBUS_PROC_CALL:
478 dev_dbg(dev, "I2C_SMBUS_PROC_CALL\n");
479 desc->wr_len_cmd = 3;
480 desc->rd_len = 2;
481 dma_size = 3;
482 dma_direction = DMA_BIDIRECTIONAL;
483 priv->dma_buffer[0] = command;
484 priv->dma_buffer[1] = data->word & 0xff;
485 priv->dma_buffer[2] = data->word >> 8;
486 break;
487
488 case I2C_SMBUS_BLOCK_DATA:
489 if (read_write == I2C_SMBUS_WRITE) {
490 /* Block Write */
491 dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: WRITE\n");
492 dma_size = data->block[0] + 1;
493 dma_direction = DMA_TO_DEVICE;
494 desc->wr_len_cmd = dma_size;
495 desc->control |= ISMT_DESC_BLK;
496 priv->dma_buffer[0] = command;
979bbf7b 497 memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1);
13f35ac1
NH		 498 } else {
499 /* Block Read */
500 dev_dbg(dev, "I2C_SMBUS_BLOCK_DATA: READ\n");
501 dma_size = I2C_SMBUS_BLOCK_MAX;
502 dma_direction = DMA_FROM_DEVICE;
503 desc->rd_len = dma_size;
504 desc->wr_len_cmd = command;
505 desc->control |= (ISMT_DESC_BLK | ISMT_DESC_CWRL);
506 }
507 break;
508
001cebf0 509 case I2C_SMBUS_I2C_BLOCK_DATA:
510 /* Make sure the length is valid */
511 if (data->block[0] < 1)
512 data->block[0] = 1;
513
514 if (data->block[0] > I2C_SMBUS_BLOCK_MAX)
515 data->block[0] = I2C_SMBUS_BLOCK_MAX;
516
517 if (read_write == I2C_SMBUS_WRITE) {
518 /* i2c Block Write */
519 dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: WRITE\n");
520 dma_size = data->block[0] + 1;
521 dma_direction = DMA_TO_DEVICE;
522 desc->wr_len_cmd = dma_size;
523 desc->control |= ISMT_DESC_I2C;
524 priv->dma_buffer[0] = command;
979bbf7b 525 memcpy(&priv->dma_buffer[1], &data->block[1], dma_size - 1);
001cebf0 526 } else {
527 /* i2c Block Read */
528 dev_dbg(dev, "I2C_SMBUS_I2C_BLOCK_DATA: READ\n");
529 dma_size = data->block[0];
530 dma_direction = DMA_FROM_DEVICE;
531 desc->rd_len = dma_size;
532 desc->wr_len_cmd = command;
533 desc->control |= (ISMT_DESC_I2C | ISMT_DESC_CWRL);
534 /*
535 * Per the "Table 15-15. I2C Commands",
536 * in the External Design Specification (EDS),
537 * (Document Number: 508084, Revision: 2.0),
538 * the _rw bit must be 0
539 */
540 desc->tgtaddr_rw = ISMT_DESC_ADDR_RW(addr, 0);
541 }
542 break;
543
13f35ac1
NH		 544 default:
545 dev_err(dev, "Unsupported transaction %d\n",
546 size);
547 return -EOPNOTSUPP;
548 }
549
550 /* map the data buffer */
551 if (dma_size != 0) {
552 dev_dbg(dev, " dev=%p\n", dev);
553 dev_dbg(dev, " data=%p\n", data);
554 dev_dbg(dev, " dma_buffer=%p\n", priv->dma_buffer);
555 dev_dbg(dev, " dma_size=%d\n", dma_size);
556 dev_dbg(dev, " dma_direction=%d\n", dma_direction);
557
558 dma_addr = dma_map_single(dev,
559 priv->dma_buffer,
560 dma_size,
561 dma_direction);
562
563 if (dma_mapping_error(dev, dma_addr)) {
564 dev_err(dev, "Error in mapping dma buffer %p\n",
565 priv->dma_buffer);
566 return -EIO;
567 }
568
569 dev_dbg(dev, " dma_addr = 0x%016llX\n",
724d5eda 570 (unsigned long long)dma_addr);
13f35ac1
NH		 571
572 desc->dptr_low = lower_32_bits(dma_addr);
573 desc->dptr_high = upper_32_bits(dma_addr);
574 }
575
16735d02 576 reinit_completion(&priv->cmp);
13f35ac1
NH		 577
578 /* Add the descriptor */
579 ismt_submit_desc(priv);
580
581 /* Now we wait for interrupt completion, 1s */
1abdd5d9 582 time_left = wait_for_completion_timeout(&priv->cmp, HZ*1);
13f35ac1
NH		 583
584 /* unmap the data buffer */
585 if (dma_size != 0)
586 dma_unmap_single(&adap->dev, dma_addr, dma_size, dma_direction);
587
1abdd5d9 588 if (unlikely(!time_left)) {
13f35ac1
NH		 589 dev_err(dev, "completion wait timed out\n");
590 ret = -ETIMEDOUT;
591 goto out;
592 }
593
594 /* do any post processing of the descriptor here */
595 ret = ismt_process_desc(desc, data, priv, size, read_write);
596
597out:
598 /* Update the ring pointer */
599 priv->head++;
600 priv->head %= ISMT_DESC_ENTRIES;
601
602 return ret;
603}
604
605/**
606 * ismt_func() - report which i2c commands are supported by this adapter
607 * @adap: the i2c host adapter
608 */
609static u32 ismt_func(struct i2c_adapter *adap)
610{
611 return I2C_FUNC_SMBUS_QUICK |
612 I2C_FUNC_SMBUS_BYTE |
613 I2C_FUNC_SMBUS_BYTE_DATA |
614 I2C_FUNC_SMBUS_WORD_DATA |
615 I2C_FUNC_SMBUS_PROC_CALL |
616 I2C_FUNC_SMBUS_BLOCK_DATA |
001cebf0 617 I2C_FUNC_SMBUS_I2C_BLOCK |
13f35ac1
NH		 618 I2C_FUNC_SMBUS_PEC;
619}
620
621/**
622 * smbus_algorithm - the adapter algorithm and supported functionality
623 * @smbus_xfer: the adapter algorithm
624 * @functionality: functionality supported by the adapter
625 */
626static const struct i2c_algorithm smbus_algorithm = {
627 .smbus_xfer = ismt_access,
628 .functionality = ismt_func,
629};
630
631/**
632 * ismt_handle_isr() - interrupt handler bottom half
633 * @priv: iSMT private data
634 */
635static irqreturn_t ismt_handle_isr(struct ismt_priv *priv)
636{
637 complete(&priv->cmp);
638
639 return IRQ_HANDLED;
640}
641
642
643/**
644 * ismt_do_interrupt() - IRQ interrupt handler
645 * @vec: interrupt vector
646 * @data: iSMT private data
647 */
648static irqreturn_t ismt_do_interrupt(int vec, void *data)
649{
650 u32 val;
651 struct ismt_priv *priv = data;
652
653 /*
654 * check to see it's our interrupt, return IRQ_NONE if not ours
655 * since we are sharing interrupt
656 */
657 val = readl(priv->smba + ISMT_MSTR_MSTS);
658
659 if (!(val & (ISMT_MSTS_MIS | ISMT_MSTS_MEIS)))
660 return IRQ_NONE;
661 else
662 writel(val | ISMT_MSTS_MIS | ISMT_MSTS_MEIS,
663 priv->smba + ISMT_MSTR_MSTS);
664
665 return ismt_handle_isr(priv);
666}
667
668/**
669 * ismt_do_msi_interrupt() - MSI interrupt handler
670 * @vec: interrupt vector
671 * @data: iSMT private data
672 */
673static irqreturn_t ismt_do_msi_interrupt(int vec, void *data)
674{
675 return ismt_handle_isr(data);
676}
677
678/**
679 * ismt_hw_init() - initialize the iSMT hardware
680 * @priv: iSMT private data
681 */
682static void ismt_hw_init(struct ismt_priv *priv)
683{
684 u32 val;
685 struct device *dev = &priv->pci_dev->dev;
686
687 /* initialize the Master Descriptor Base Address (MDBA) */
688 writeq(priv->io_rng_dma, priv->smba + ISMT_MSTR_MDBA);
689
690 /* initialize the Master Control Register (MCTRL) */
691 writel(ISMT_MCTRL_MEIE, priv->smba + ISMT_MSTR_MCTRL);
692
693 /* initialize the Master Status Register (MSTS) */
694 writel(0, priv->smba + ISMT_MSTR_MSTS);
695
696 /* initialize the Master Descriptor Size (MDS) */
697 val = readl(priv->smba + ISMT_MSTR_MDS);
698 writel((val & ~ISMT_MDS_MASK) | (ISMT_DESC_ENTRIES - 1),
699 priv->smba + ISMT_MSTR_MDS);
700
701 /*
702 * Set the SMBus speed (could use this for slow HW debuggers)
703 */
704
705 val = readl(priv->smba + ISMT_SPGT);
706
707 switch (bus_speed) {
708 case 0:
709 break;
710
711 case 80:
712 dev_dbg(dev, "Setting SMBus clock to 80 kHz\n");
713 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_80K),
714 priv->smba + ISMT_SPGT);
715 break;
716
717 case 100:
718 dev_dbg(dev, "Setting SMBus clock to 100 kHz\n");
719 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_100K),
720 priv->smba + ISMT_SPGT);
721 break;
722
723 case 400:
724 dev_dbg(dev, "Setting SMBus clock to 400 kHz\n");
725 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_400K),
726 priv->smba + ISMT_SPGT);
727 break;
728
729 case 1000:
730 dev_dbg(dev, "Setting SMBus clock to 1000 kHz\n");
731 writel(((val & ~ISMT_SPGT_SPD_MASK) | ISMT_SPGT_SPD_1M),
732 priv->smba + ISMT_SPGT);
733 break;
734
735 default:
736 dev_warn(dev, "Invalid SMBus clock speed, only 0, 80, 100, 400, and 1000 are valid\n");
737 break;
738 }
739
740 val = readl(priv->smba + ISMT_SPGT);
741
742 switch (val & ISMT_SPGT_SPD_MASK) {
743 case ISMT_SPGT_SPD_80K:
744 bus_speed = 80;
745 break;
746 case ISMT_SPGT_SPD_100K:
747 bus_speed = 100;
748 break;
749 case ISMT_SPGT_SPD_400K:
750 bus_speed = 400;
751 break;
752 case ISMT_SPGT_SPD_1M:
753 bus_speed = 1000;
754 break;
755 }
756 dev_dbg(dev, "SMBus clock is running at %d kHz\n", bus_speed);
757}
758
759/**
760 * ismt_dev_init() - initialize the iSMT data structures
761 * @priv: iSMT private data
762 */
763static int ismt_dev_init(struct ismt_priv *priv)
764{
765 /* allocate memory for the descriptor */
766 priv->hw = dmam_alloc_coherent(&priv->pci_dev->dev,
767 (ISMT_DESC_ENTRIES
768 * sizeof(struct ismt_desc)),
769 &priv->io_rng_dma,
770 GFP_KERNEL);
771 if (!priv->hw)
772 return -ENOMEM;
773
774 memset(priv->hw, 0, (ISMT_DESC_ENTRIES * sizeof(struct ismt_desc)));
775
776 priv->head = 0;
777 init_completion(&priv->cmp);
778
779 return 0;
780}
781
782/**
783 * ismt_int_init() - initialize interrupts
784 * @priv: iSMT private data
785 */
786static int ismt_int_init(struct ismt_priv *priv)
787{
788 int err;
789
790 /* Try using MSI interrupts */
791 err = pci_enable_msi(priv->pci_dev);
792 if (err) {
793 dev_warn(&priv->pci_dev->dev,
794 "Unable to use MSI interrupts, falling back to legacy\n");
795 goto intx;
796 }
797
798 err = devm_request_irq(&priv->pci_dev->dev,
799 priv->pci_dev->irq,
800 ismt_do_msi_interrupt,
801 0,
802 "ismt-msi",
803 priv);
804 if (err) {
805 pci_disable_msi(priv->pci_dev);
806 goto intx;
807 }
808
809 priv->using_msi = true;
810 goto done;
811
812 /* Try using legacy interrupts */
813intx:
814 err = devm_request_irq(&priv->pci_dev->dev,
815 priv->pci_dev->irq,
816 ismt_do_interrupt,
817 IRQF_SHARED,
818 "ismt-intx",
819 priv);
820 if (err) {
821 dev_err(&priv->pci_dev->dev, "no usable interrupts\n");
822 return -ENODEV;
823 }
824
825 priv->using_msi = false;
826
827done:
828 return 0;
829}
830
831static struct pci_driver ismt_driver;
832
833/**
834 * ismt_probe() - probe for iSMT devices
835 * @pdev: PCI-Express device
836 * @id: PCI-Express device ID
837 */
838static int
839ismt_probe(struct pci_dev *pdev, const struct pci_device_id *id)
840{
841 int err;
842 struct ismt_priv *priv;
843 unsigned long start, len;
844
845 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
846 if (!priv)
847 return -ENOMEM;
848
849 pci_set_drvdata(pdev, priv);
850 i2c_set_adapdata(&priv->adapter, priv);
851 priv->adapter.owner = THIS_MODULE;
852
853 priv->adapter.class = I2C_CLASS_HWMON;
854
855 priv->adapter.algo = &smbus_algorithm;
856
857 /* set up the sysfs linkage to our parent device */
858 priv->adapter.dev.parent = &pdev->dev;
859
860 /* number of retries on lost arbitration */
861 priv->adapter.retries = ISMT_MAX_RETRIES;
862
863 priv->pci_dev = pdev;
864
865 err = pcim_enable_device(pdev);
866 if (err) {
867 dev_err(&pdev->dev, "Failed to enable SMBus PCI device (%d)\n",
868 err);
869 return err;
870 }
871
872 /* enable bus mastering */
873 pci_set_master(pdev);
874
875 /* Determine the address of the SMBus area */
876 start = pci_resource_start(pdev, SMBBAR);
877 len = pci_resource_len(pdev, SMBBAR);
878 if (!start || !len) {
879 dev_err(&pdev->dev,
880 "SMBus base address uninitialized, upgrade BIOS\n");
881 return -ENODEV;
882 }
883
884 snprintf(priv->adapter.name, sizeof(priv->adapter.name),
885 "SMBus iSMT adapter at %lx", start);
886
887 dev_dbg(&priv->pci_dev->dev, " start=0x%lX\n", start);
888 dev_dbg(&priv->pci_dev->dev, " len=0x%lX\n", len);
889
890 err = acpi_check_resource_conflict(&pdev->resource[SMBBAR]);
891 if (err) {
892 dev_err(&pdev->dev, "ACPI resource conflict!\n");
893 return err;
894 }
895
896 err = pci_request_region(pdev, SMBBAR, ismt_driver.name);
897 if (err) {
898 dev_err(&pdev->dev,
899 "Failed to request SMBus region 0x%lx-0x%lx\n",
900 start, start + len);
901 return err;
902 }
903
904 priv->smba = pcim_iomap(pdev, SMBBAR, len);
905 if (!priv->smba) {
906 dev_err(&pdev->dev, "Unable to ioremap SMBus BAR\n");
907 err = -ENODEV;
908 goto fail;
909 }
910
911 if ((pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) != 0) ||
912 (pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)) != 0)) {
913 if ((pci_set_dma_mask(pdev, DMA_BIT_MASK(32)) != 0) ||
914 (pci_set_consistent_dma_mask(pdev,
915 DMA_BIT_MASK(32)) != 0)) {
916 dev_err(&pdev->dev, "pci_set_dma_mask fail %p\n",
917 pdev);
370257b2 918 err = -ENODEV;
13f35ac1
NH		 919 goto fail;
920 }
921 }
922
923 err = ismt_dev_init(priv);
924 if (err)
925 goto fail;
926
927 ismt_hw_init(priv);
928
929 err = ismt_int_init(priv);
930 if (err)
931 goto fail;
932
933 err = i2c_add_adapter(&priv->adapter);
934 if (err) {
935 dev_err(&pdev->dev, "Failed to add SMBus iSMT adapter\n");
936 err = -ENODEV;
937 goto fail;
938 }
939 return 0;
940
941fail:
942 pci_release_region(pdev, SMBBAR);
943 return err;
944}
945
946/**
947 * ismt_remove() - release driver resources
948 * @pdev: PCI-Express device
949 */
950static void ismt_remove(struct pci_dev *pdev)
951{
952 struct ismt_priv *priv = pci_get_drvdata(pdev);
953
954 i2c_del_adapter(&priv->adapter);
955 pci_release_region(pdev, SMBBAR);
956}
957
958/**
959 * ismt_suspend() - place the device in suspend
960 * @pdev: PCI-Express device
961 * @mesg: PM message
962 */
963#ifdef CONFIG_PM
964static int ismt_suspend(struct pci_dev *pdev, pm_message_t mesg)
965{
966 pci_save_state(pdev);
967 pci_set_power_state(pdev, pci_choose_state(pdev, mesg));
968 return 0;
969}
970
971/**
972 * ismt_resume() - PCI resume code
973 * @pdev: PCI-Express device
974 */
975static int ismt_resume(struct pci_dev *pdev)
976{
977 pci_set_power_state(pdev, PCI_D0);
978 pci_restore_state(pdev);
979 return pci_enable_device(pdev);
980}
981
982#else
983
984#define ismt_suspend NULL
985#define ismt_resume NULL
986
987#endif
988
989static struct pci_driver ismt_driver = {
990 .name = "ismt_smbus",
991 .id_table = ismt_ids,
992 .probe = ismt_probe,
993 .remove = ismt_remove,
994 .suspend = ismt_suspend,
995 .resume = ismt_resume,
996};
997
998module_pci_driver(ismt_driver);
999
1000MODULE_LICENSE("Dual BSD/GPL");
1001MODULE_AUTHOR("Bill E. Brown <bill.e.brown@intel.com>");
1002MODULE_DESCRIPTION("Intel SMBus Message Transport (iSMT) driver");
Linux kernel - Deliverables
This page took 0.174159 seconds and 5 git commands to generate.