1 /*
2  * intel_scu_ipc.c: Driver for the Intel SCU IPC mechanism
3  *
4  * (C) Copyright 2008-2010,2015 Intel Corporation
5  * Author: Sreedhara DS (sreedhara.ds@intel.com)
6  *
7  * This program is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU General Public License
9  * as published by the Free Software Foundation; version 2
10  * of the License.
11  *
12  * SCU running in ARC processor communicates with other entity running in IA
13  * core through IPC mechanism which in turn messaging between IA core ad SCU.
14  * SCU has two IPC mechanism IPC-1 and IPC-2. IPC-1 is used between IA32 and
15  * SCU where IPC-2 is used between P-Unit and SCU. This driver delas with
16  * IPC-1 Driver provides an API for power control unit registers (e.g. MSIC)
17  * along with other APIs.
18  */
19 #include <linux/delay.h>
20 #include <linux/errno.h>
21 #include <linux/init.h>
22 #include <linux/device.h>
23 #include <linux/pm.h>
24 #include <linux/pci.h>
25 #include <linux/interrupt.h>
26 #include <linux/sfi.h>
27 #include <asm/intel-mid.h>
28 #include <asm/intel_scu_ipc.h>
29 
30 /* IPC defines the following message types */
31 #define IPCMSG_WATCHDOG_TIMER 0xF8 /* Set Kernel Watchdog Threshold */
32 #define IPCMSG_BATTERY        0xEF /* Coulomb Counter Accumulator */
33 #define IPCMSG_FW_UPDATE      0xFE /* Firmware update */
34 #define IPCMSG_PCNTRL         0xFF /* Power controller unit read/write */
35 #define IPCMSG_FW_REVISION    0xF4 /* Get firmware revision */
36 
37 /* Command id associated with message IPCMSG_PCNTRL */
38 #define IPC_CMD_PCNTRL_W      0 /* Register write */
39 #define IPC_CMD_PCNTRL_R      1 /* Register read */
40 #define IPC_CMD_PCNTRL_M      2 /* Register read-modify-write */
41 
42 /*
43  * IPC register summary
44  *
45  * IPC register blocks are memory mapped at fixed address of PCI BAR 0.
46  * To read or write information to the SCU, driver writes to IPC-1 memory
47  * mapped registers. The following is the IPC mechanism
48  *
49  * 1. IA core cDMI interface claims this transaction and converts it to a
50  *    Transaction Layer Packet (TLP) message which is sent across the cDMI.
51  *
52  * 2. South Complex cDMI block receives this message and writes it to
53  *    the IPC-1 register block, causing an interrupt to the SCU
54  *
55  * 3. SCU firmware decodes this interrupt and IPC message and the appropriate
56  *    message handler is called within firmware.
57  */
58 
59 #define IPC_WWBUF_SIZE    20		/* IPC Write buffer Size */
60 #define IPC_RWBUF_SIZE    20		/* IPC Read buffer Size */
61 #define IPC_IOC	          0x100		/* IPC command register IOC bit */
62 
63 #define PCI_DEVICE_ID_LINCROFT		0x082a
64 #define PCI_DEVICE_ID_PENWELL		0x080e
65 #define PCI_DEVICE_ID_CLOVERVIEW	0x08ea
66 #define PCI_DEVICE_ID_TANGIER		0x11a0
67 
68 /* intel scu ipc driver data */
69 struct intel_scu_ipc_pdata_t {
70 	u32 i2c_base;
71 	u32 i2c_len;
72 	u8 irq_mode;
73 };
74 
75 static const struct intel_scu_ipc_pdata_t intel_scu_ipc_lincroft_pdata = {
76 	.i2c_base = 0xff12b000,
77 	.i2c_len = 0x10,
78 	.irq_mode = 0,
79 };
80 
81 /* Penwell and Cloverview */
82 static const struct intel_scu_ipc_pdata_t intel_scu_ipc_penwell_pdata = {
83 	.i2c_base = 0xff12b000,
84 	.i2c_len = 0x10,
85 	.irq_mode = 1,
86 };
87 
88 static const struct intel_scu_ipc_pdata_t intel_scu_ipc_tangier_pdata = {
89 	.i2c_base  = 0xff00d000,
90 	.i2c_len = 0x10,
91 	.irq_mode = 0,
92 };
93 
94 struct intel_scu_ipc_dev {
95 	struct device *dev;
96 	void __iomem *ipc_base;
97 	void __iomem *i2c_base;
98 	struct completion cmd_complete;
99 	u8 irq_mode;
100 };
101 
102 static struct intel_scu_ipc_dev  ipcdev; /* Only one for now */
103 
104 /*
105  * IPC Read Buffer (Read Only):
106  * 16 byte buffer for receiving data from SCU, if IPC command
107  * processing results in response data
108  */
109 #define IPC_READ_BUFFER		0x90
110 
111 #define IPC_I2C_CNTRL_ADDR	0
112 #define I2C_DATA_ADDR		0x04
113 
114 static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */
115 
116 /*
117  * Send ipc command
118  * Command Register (Write Only):
119  * A write to this register results in an interrupt to the SCU core processor
120  * Format:
121  * |rfu2(8) | size(8) | command id(4) | rfu1(3) | ioc(1) | command(8)|
122  */
123 static inline void ipc_command(struct intel_scu_ipc_dev *scu, u32 cmd)
124 {
125 	if (scu->irq_mode) {
126 		reinit_completion(&scu->cmd_complete);
127 		writel(cmd | IPC_IOC, scu->ipc_base);
128 	}
129 	writel(cmd, scu->ipc_base);
130 }
131 
132 /*
133  * Write ipc data
134  * IPC Write Buffer (Write Only):
135  * 16-byte buffer for sending data associated with IPC command to
136  * SCU. Size of the data is specified in the IPC_COMMAND_REG register
137  */
138 static inline void ipc_data_writel(struct intel_scu_ipc_dev *scu, u32 data, u32 offset)
139 {
140 	writel(data, scu->ipc_base + 0x80 + offset);
141 }
142 
143 /*
144  * Status Register (Read Only):
145  * Driver will read this register to get the ready/busy status of the IPC
146  * block and error status of the IPC command that was just processed by SCU
147  * Format:
148  * |rfu3(8)|error code(8)|initiator id(8)|cmd id(4)|rfu1(2)|error(1)|busy(1)|
149  */
150 static inline u8 ipc_read_status(struct intel_scu_ipc_dev *scu)
151 {
152 	return __raw_readl(scu->ipc_base + 0x04);
153 }
154 
155 /* Read ipc byte data */
156 static inline u8 ipc_data_readb(struct intel_scu_ipc_dev *scu, u32 offset)
157 {
158 	return readb(scu->ipc_base + IPC_READ_BUFFER + offset);
159 }
160 
161 /* Read ipc u32 data */
162 static inline u32 ipc_data_readl(struct intel_scu_ipc_dev *scu, u32 offset)
163 {
164 	return readl(scu->ipc_base + IPC_READ_BUFFER + offset);
165 }
166 
167 /* Wait till scu status is busy */
168 static inline int busy_loop(struct intel_scu_ipc_dev *scu)
169 {
170 	u32 status = ipc_read_status(scu);
171 	u32 loop_count = 100000;
172 
173 	/* break if scu doesn't reset busy bit after huge retry */
174 	while ((status & BIT(0)) && --loop_count) {
175 		udelay(1); /* scu processing time is in few u secods */
176 		status = ipc_read_status(scu);
177 	}
178 
179 	if (status & BIT(0)) {
180 		dev_err(scu->dev, "IPC timed out");
181 		return -ETIMEDOUT;
182 	}
183 
184 	if (status & BIT(1))
185 		return -EIO;
186 
187 	return 0;
188 }
189 
190 /* Wait till ipc ioc interrupt is received or timeout in 3 HZ */
191 static inline int ipc_wait_for_interrupt(struct intel_scu_ipc_dev *scu)
192 {
193 	int status;
194 
195 	if (!wait_for_completion_timeout(&scu->cmd_complete, 3 * HZ)) {
196 		dev_err(scu->dev, "IPC timed out\n");
197 		return -ETIMEDOUT;
198 	}
199 
200 	status = ipc_read_status(scu);
201 	if (status & BIT(1))
202 		return -EIO;
203 
204 	return 0;
205 }
206 
207 static int intel_scu_ipc_check_status(struct intel_scu_ipc_dev *scu)
208 {
209 	return scu->irq_mode ? ipc_wait_for_interrupt(scu) : busy_loop(scu);
210 }
211 
212 /* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */
213 static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
214 {
215 	struct intel_scu_ipc_dev *scu = &ipcdev;
216 	int nc;
217 	u32 offset = 0;
218 	int err;
219 	u8 cbuf[IPC_WWBUF_SIZE];
220 	u32 *wbuf = (u32 *)&cbuf;
221 
222 	memset(cbuf, 0, sizeof(cbuf));
223 
224 	mutex_lock(&ipclock);
225 
226 	if (scu->dev == NULL) {
227 		mutex_unlock(&ipclock);
228 		return -ENODEV;
229 	}
230 
231 	for (nc = 0; nc < count; nc++, offset += 2) {
232 		cbuf[offset] = addr[nc];
233 		cbuf[offset + 1] = addr[nc] >> 8;
234 	}
235 
236 	if (id == IPC_CMD_PCNTRL_R) {
237 		for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
238 			ipc_data_writel(scu, wbuf[nc], offset);
239 		ipc_command(scu, (count * 2) << 16 | id << 12 | 0 << 8 | op);
240 	} else if (id == IPC_CMD_PCNTRL_W) {
241 		for (nc = 0; nc < count; nc++, offset += 1)
242 			cbuf[offset] = data[nc];
243 		for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
244 			ipc_data_writel(scu, wbuf[nc], offset);
245 		ipc_command(scu, (count * 3) << 16 | id << 12 | 0 << 8 | op);
246 	} else if (id == IPC_CMD_PCNTRL_M) {
247 		cbuf[offset] = data[0];
248 		cbuf[offset + 1] = data[1];
249 		ipc_data_writel(scu, wbuf[0], 0); /* Write wbuff */
250 		ipc_command(scu, 4 << 16 | id << 12 | 0 << 8 | op);
251 	}
252 
253 	err = intel_scu_ipc_check_status(scu);
254 	if (!err && id == IPC_CMD_PCNTRL_R) { /* Read rbuf */
255 		/* Workaround: values are read as 0 without memcpy_fromio */
256 		memcpy_fromio(cbuf, scu->ipc_base + 0x90, 16);
257 		for (nc = 0; nc < count; nc++)
258 			data[nc] = ipc_data_readb(scu, nc);
259 	}
260 	mutex_unlock(&ipclock);
261 	return err;
262 }
263 
264 /**
265  *	intel_scu_ipc_ioread8		-	read a word via the SCU
266  *	@addr: register on SCU
267  *	@data: return pointer for read byte
268  *
269  *	Read a single register. Returns 0 on success or an error code. All
270  *	locking between SCU accesses is handled for the caller.
271  *
272  *	This function may sleep.
273  */
274 int intel_scu_ipc_ioread8(u16 addr, u8 *data)
275 {
276 	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
277 }
278 EXPORT_SYMBOL(intel_scu_ipc_ioread8);
279 
280 /**
281  *	intel_scu_ipc_ioread16		-	read a word via the SCU
282  *	@addr: register on SCU
283  *	@data: return pointer for read word
284  *
285  *	Read a register pair. Returns 0 on success or an error code. All
286  *	locking between SCU accesses is handled for the caller.
287  *
288  *	This function may sleep.
289  */
290 int intel_scu_ipc_ioread16(u16 addr, u16 *data)
291 {
292 	u16 x[2] = {addr, addr + 1};
293 	return pwr_reg_rdwr(x, (u8 *)data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
294 }
295 EXPORT_SYMBOL(intel_scu_ipc_ioread16);
296 
297 /**
298  *	intel_scu_ipc_ioread32		-	read a dword via the SCU
299  *	@addr: register on SCU
300  *	@data: return pointer for read dword
301  *
302  *	Read four registers. Returns 0 on success or an error code. All
303  *	locking between SCU accesses is handled for the caller.
304  *
305  *	This function may sleep.
306  */
307 int intel_scu_ipc_ioread32(u16 addr, u32 *data)
308 {
309 	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
310 	return pwr_reg_rdwr(x, (u8 *)data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
311 }
312 EXPORT_SYMBOL(intel_scu_ipc_ioread32);
313 
314 /**
315  *	intel_scu_ipc_iowrite8		-	write a byte via the SCU
316  *	@addr: register on SCU
317  *	@data: byte to write
318  *
319  *	Write a single register. Returns 0 on success or an error code. All
320  *	locking between SCU accesses is handled for the caller.
321  *
322  *	This function may sleep.
323  */
324 int intel_scu_ipc_iowrite8(u16 addr, u8 data)
325 {
326 	return pwr_reg_rdwr(&addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
327 }
328 EXPORT_SYMBOL(intel_scu_ipc_iowrite8);
329 
330 /**
331  *	intel_scu_ipc_iowrite16		-	write a word via the SCU
332  *	@addr: register on SCU
333  *	@data: word to write
334  *
335  *	Write two registers. Returns 0 on success or an error code. All
336  *	locking between SCU accesses is handled for the caller.
337  *
338  *	This function may sleep.
339  */
340 int intel_scu_ipc_iowrite16(u16 addr, u16 data)
341 {
342 	u16 x[2] = {addr, addr + 1};
343 	return pwr_reg_rdwr(x, (u8 *)&data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
344 }
345 EXPORT_SYMBOL(intel_scu_ipc_iowrite16);
346 
347 /**
348  *	intel_scu_ipc_iowrite32		-	write a dword via the SCU
349  *	@addr: register on SCU
350  *	@data: dword to write
351  *
352  *	Write four registers. Returns 0 on success or an error code. All
353  *	locking between SCU accesses is handled for the caller.
354  *
355  *	This function may sleep.
356  */
357 int intel_scu_ipc_iowrite32(u16 addr, u32 data)
358 {
359 	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
360 	return pwr_reg_rdwr(x, (u8 *)&data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
361 }
362 EXPORT_SYMBOL(intel_scu_ipc_iowrite32);
363 
364 /**
365  *	intel_scu_ipc_readvv		-	read a set of registers
366  *	@addr: register list
367  *	@data: bytes to return
368  *	@len: length of array
369  *
370  *	Read registers. Returns 0 on success or an error code. All
371  *	locking between SCU accesses is handled for the caller.
372  *
373  *	The largest array length permitted by the hardware is 5 items.
374  *
375  *	This function may sleep.
376  */
377 int intel_scu_ipc_readv(u16 *addr, u8 *data, int len)
378 {
379 	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
380 }
381 EXPORT_SYMBOL(intel_scu_ipc_readv);
382 
383 /**
384  *	intel_scu_ipc_writev		-	write a set of registers
385  *	@addr: register list
386  *	@data: bytes to write
387  *	@len: length of array
388  *
389  *	Write registers. Returns 0 on success or an error code. All
390  *	locking between SCU accesses is handled for the caller.
391  *
392  *	The largest array length permitted by the hardware is 5 items.
393  *
394  *	This function may sleep.
395  *
396  */
397 int intel_scu_ipc_writev(u16 *addr, u8 *data, int len)
398 {
399 	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
400 }
401 EXPORT_SYMBOL(intel_scu_ipc_writev);
402 
403 /**
404  *	intel_scu_ipc_update_register	-	r/m/w a register
405  *	@addr: register address
406  *	@bits: bits to update
407  *	@mask: mask of bits to update
408  *
409  *	Read-modify-write power control unit register. The first data argument
410  *	must be register value and second is mask value
411  *	mask is a bitmap that indicates which bits to update.
412  *	0 = masked. Don't modify this bit, 1 = modify this bit.
413  *	returns 0 on success or an error code.
414  *
415  *	This function may sleep. Locking between SCU accesses is handled
416  *	for the caller.
417  */
418 int intel_scu_ipc_update_register(u16 addr, u8 bits, u8 mask)
419 {
420 	u8 data[2] = { bits, mask };
421 	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M);
422 }
423 EXPORT_SYMBOL(intel_scu_ipc_update_register);
424 
425 /**
426  *	intel_scu_ipc_simple_command	-	send a simple command
427  *	@cmd: command
428  *	@sub: sub type
429  *
430  *	Issue a simple command to the SCU. Do not use this interface if
431  *	you must then access data as any data values may be overwritten
432  *	by another SCU access by the time this function returns.
433  *
434  *	This function may sleep. Locking for SCU accesses is handled for
435  *	the caller.
436  */
437 int intel_scu_ipc_simple_command(int cmd, int sub)
438 {
439 	struct intel_scu_ipc_dev *scu = &ipcdev;
440 	int err;
441 
442 	mutex_lock(&ipclock);
443 	if (scu->dev == NULL) {
444 		mutex_unlock(&ipclock);
445 		return -ENODEV;
446 	}
447 	ipc_command(scu, sub << 12 | cmd);
448 	err = intel_scu_ipc_check_status(scu);
449 	mutex_unlock(&ipclock);
450 	return err;
451 }
452 EXPORT_SYMBOL(intel_scu_ipc_simple_command);
453 
454 /**
455  *	intel_scu_ipc_command	-	command with data
456  *	@cmd: command
457  *	@sub: sub type
458  *	@in: input data
459  *	@inlen: input length in dwords
460  *	@out: output data
461  *	@outlein: output length in dwords
462  *
463  *	Issue a command to the SCU which involves data transfers. Do the
464  *	data copies under the lock but leave it for the caller to interpret
465  */
466 int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
467 			  u32 *out, int outlen)
468 {
469 	struct intel_scu_ipc_dev *scu = &ipcdev;
470 	int i, err;
471 
472 	mutex_lock(&ipclock);
473 	if (scu->dev == NULL) {
474 		mutex_unlock(&ipclock);
475 		return -ENODEV;
476 	}
477 
478 	for (i = 0; i < inlen; i++)
479 		ipc_data_writel(scu, *in++, 4 * i);
480 
481 	ipc_command(scu, (inlen << 16) | (sub << 12) | cmd);
482 	err = intel_scu_ipc_check_status(scu);
483 
484 	if (!err) {
485 		for (i = 0; i < outlen; i++)
486 			*out++ = ipc_data_readl(scu, 4 * i);
487 	}
488 
489 	mutex_unlock(&ipclock);
490 	return err;
491 }
492 EXPORT_SYMBOL(intel_scu_ipc_command);
493 
494 #define IPC_SPTR		0x08
495 #define IPC_DPTR		0x0C
496 
497 /**
498  * intel_scu_ipc_raw_command() - IPC command with data and pointers
499  * @cmd:	IPC command code.
500  * @sub:	IPC command sub type.
501  * @in:		input data of this IPC command.
502  * @inlen:	input data length in dwords.
503  * @out:	output data of this IPC command.
504  * @outlen:	output data length in dwords.
505  * @sptr:	data writing to SPTR register.
506  * @dptr:	data writing to DPTR register.
507  *
508  * Send an IPC command to SCU with input/output data and source/dest pointers.
509  *
510  * Return:	an IPC error code or 0 on success.
511  */
512 int intel_scu_ipc_raw_command(int cmd, int sub, u8 *in, int inlen,
513 			      u32 *out, int outlen, u32 dptr, u32 sptr)
514 {
515 	struct intel_scu_ipc_dev *scu = &ipcdev;
516 	int inbuflen = DIV_ROUND_UP(inlen, 4);
517 	u32 inbuf[4];
518 	int i, err;
519 
520 	/* Up to 16 bytes */
521 	if (inbuflen > 4)
522 		return -EINVAL;
523 
524 	mutex_lock(&ipclock);
525 	if (scu->dev == NULL) {
526 		mutex_unlock(&ipclock);
527 		return -ENODEV;
528 	}
529 
530 	writel(dptr, scu->ipc_base + IPC_DPTR);
531 	writel(sptr, scu->ipc_base + IPC_SPTR);
532 
533 	/*
534 	 * SRAM controller doesn't support 8-bit writes, it only
535 	 * supports 32-bit writes, so we have to copy input data into
536 	 * the temporary buffer, and SCU FW will use the inlen to
537 	 * determine the actual input data length in the temporary
538 	 * buffer.
539 	 */
540 	memcpy(inbuf, in, inlen);
541 
542 	for (i = 0; i < inbuflen; i++)
543 		ipc_data_writel(scu, inbuf[i], 4 * i);
544 
545 	ipc_command(scu, (inlen << 16) | (sub << 12) | cmd);
546 	err = intel_scu_ipc_check_status(scu);
547 	if (!err) {
548 		for (i = 0; i < outlen; i++)
549 			*out++ = ipc_data_readl(scu, 4 * i);
550 	}
551 
552 	mutex_unlock(&ipclock);
553 	return err;
554 }
555 EXPORT_SYMBOL_GPL(intel_scu_ipc_raw_command);
556 
557 /* I2C commands */
558 #define IPC_I2C_WRITE 1 /* I2C Write command */
559 #define IPC_I2C_READ  2 /* I2C Read command */
560 
561 /**
562  *	intel_scu_ipc_i2c_cntrl		-	I2C read/write operations
563  *	@addr: I2C address + command bits
564  *	@data: data to read/write
565  *
566  *	Perform an an I2C read/write operation via the SCU. All locking is
567  *	handled for the caller. This function may sleep.
568  *
569  *	Returns an error code or 0 on success.
570  *
571  *	This has to be in the IPC driver for the locking.
572  */
573 int intel_scu_ipc_i2c_cntrl(u32 addr, u32 *data)
574 {
575 	struct intel_scu_ipc_dev *scu = &ipcdev;
576 	u32 cmd = 0;
577 
578 	mutex_lock(&ipclock);
579 	if (scu->dev == NULL) {
580 		mutex_unlock(&ipclock);
581 		return -ENODEV;
582 	}
583 	cmd = (addr >> 24) & 0xFF;
584 	if (cmd == IPC_I2C_READ) {
585 		writel(addr, scu->i2c_base + IPC_I2C_CNTRL_ADDR);
586 		/* Write not getting updated without delay */
587 		usleep_range(1000, 2000);
588 		*data = readl(scu->i2c_base + I2C_DATA_ADDR);
589 	} else if (cmd == IPC_I2C_WRITE) {
590 		writel(*data, scu->i2c_base + I2C_DATA_ADDR);
591 		usleep_range(1000, 2000);
592 		writel(addr, scu->i2c_base + IPC_I2C_CNTRL_ADDR);
593 	} else {
594 		dev_err(scu->dev,
595 			"intel_scu_ipc: I2C INVALID_CMD = 0x%x\n", cmd);
596 
597 		mutex_unlock(&ipclock);
598 		return -EIO;
599 	}
600 	mutex_unlock(&ipclock);
601 	return 0;
602 }
603 EXPORT_SYMBOL(intel_scu_ipc_i2c_cntrl);
604 
605 /*
606  * Interrupt handler gets called when ioc bit of IPC_COMMAND_REG set to 1
607  * When ioc bit is set to 1, caller api must wait for interrupt handler called
608  * which in turn unlocks the caller api. Currently this is not used
609  *
610  * This is edge triggered so we need take no action to clear anything
611  */
612 static irqreturn_t ioc(int irq, void *dev_id)
613 {
614 	struct intel_scu_ipc_dev *scu = dev_id;
615 
616 	if (scu->irq_mode)
617 		complete(&scu->cmd_complete);
618 
619 	return IRQ_HANDLED;
620 }
621 
622 /**
623  *	ipc_probe	-	probe an Intel SCU IPC
624  *	@pdev: the PCI device matching
625  *	@id: entry in the match table
626  *
627  *	Enable and install an intel SCU IPC. This appears in the PCI space
628  *	but uses some hard coded addresses as well.
629  */
630 static int ipc_probe(struct pci_dev *pdev, const struct pci_device_id *id)
631 {
632 	int err;
633 	struct intel_scu_ipc_dev *scu = &ipcdev;
634 	struct intel_scu_ipc_pdata_t *pdata;
635 
636 	if (scu->dev)		/* We support only one SCU */
637 		return -EBUSY;
638 
639 	pdata = (struct intel_scu_ipc_pdata_t *)id->driver_data;
640 	if (!pdata)
641 		return -ENODEV;
642 
643 	scu->irq_mode = pdata->irq_mode;
644 
645 	err = pcim_enable_device(pdev);
646 	if (err)
647 		return err;
648 
649 	err = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
650 	if (err)
651 		return err;
652 
653 	init_completion(&scu->cmd_complete);
654 
655 	scu->ipc_base = pcim_iomap_table(pdev)[0];
656 
657 	scu->i2c_base = ioremap_nocache(pdata->i2c_base, pdata->i2c_len);
658 	if (!scu->i2c_base)
659 		return -ENOMEM;
660 
661 	err = devm_request_irq(&pdev->dev, pdev->irq, ioc, 0, "intel_scu_ipc",
662 			       scu);
663 	if (err)
664 		return err;
665 
666 	/* Assign device at last */
667 	scu->dev = &pdev->dev;
668 
669 	intel_scu_devices_create();
670 
671 	pci_set_drvdata(pdev, scu);
672 	return 0;
673 }
674 
675 #define SCU_DEVICE(id, pdata)	{PCI_VDEVICE(INTEL, id), (kernel_ulong_t)&pdata}
676 
677 static const struct pci_device_id pci_ids[] = {
678 	SCU_DEVICE(PCI_DEVICE_ID_LINCROFT,	intel_scu_ipc_lincroft_pdata),
679 	SCU_DEVICE(PCI_DEVICE_ID_PENWELL,	intel_scu_ipc_penwell_pdata),
680 	SCU_DEVICE(PCI_DEVICE_ID_CLOVERVIEW,	intel_scu_ipc_penwell_pdata),
681 	SCU_DEVICE(PCI_DEVICE_ID_TANGIER,	intel_scu_ipc_tangier_pdata),
682 	{}
683 };
684 
685 static struct pci_driver ipc_driver = {
686 	.driver = {
687 		.suppress_bind_attrs = true,
688 	},
689 	.name = "intel_scu_ipc",
690 	.id_table = pci_ids,
691 	.probe = ipc_probe,
692 };
693 builtin_pci_driver(ipc_driver);
694