1 /*
2  * intel_scu_ipc.c: Driver for the Intel SCU IPC mechanism
3  *
4  * (C) Copyright 2008-2010 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 <linux/module.h>
28 #include <asm/intel-mid.h>
29 #include <asm/intel_scu_ipc.h>
30 
31 /* IPC defines the following message types */
32 #define IPCMSG_WATCHDOG_TIMER 0xF8 /* Set Kernel Watchdog Threshold */
33 #define IPCMSG_BATTERY        0xEF /* Coulomb Counter Accumulator */
34 #define IPCMSG_FW_UPDATE      0xFE /* Firmware update */
35 #define IPCMSG_PCNTRL         0xFF /* Power controller unit read/write */
36 #define IPCMSG_FW_REVISION    0xF4 /* Get firmware revision */
37 
38 /* Command id associated with message IPCMSG_PCNTRL */
39 #define IPC_CMD_PCNTRL_W      0 /* Register write */
40 #define IPC_CMD_PCNTRL_R      1 /* Register read */
41 #define IPC_CMD_PCNTRL_M      2 /* Register read-modify-write */
42 
43 /*
44  * IPC register summary
45  *
46  * IPC register blocks are memory mapped at fixed address of 0xFF11C000
47  * To read or write information to the SCU, driver writes to IPC-1 memory
48  * mapped registers (base address 0xFF11C000). The following is the IPC
49  * mechanism
50  *
51  * 1. IA core cDMI interface claims this transaction and converts it to a
52  *    Transaction Layer Packet (TLP) message which is sent across the cDMI.
53  *
54  * 2. South Complex cDMI block receives this message and writes it to
55  *    the IPC-1 register block, causing an interrupt to the SCU
56  *
57  * 3. SCU firmware decodes this interrupt and IPC message and the appropriate
58  *    message handler is called within firmware.
59  */
60 
61 #define IPC_WWBUF_SIZE    20		/* IPC Write buffer Size */
62 #define IPC_RWBUF_SIZE    20		/* IPC Read buffer Size */
63 #define IPC_IOC	          0x100		/* IPC command register IOC bit */
64 
65 enum {
66 	SCU_IPC_LINCROFT,
67 	SCU_IPC_PENWELL,
68 	SCU_IPC_CLOVERVIEW,
69 	SCU_IPC_TANGIER,
70 };
71 
72 /* intel scu ipc driver data*/
73 struct intel_scu_ipc_pdata_t {
74 	u32 ipc_base;
75 	u32 i2c_base;
76 	u32 ipc_len;
77 	u32 i2c_len;
78 	u8 irq_mode;
79 };
80 
81 static struct intel_scu_ipc_pdata_t intel_scu_ipc_pdata[] = {
82 	[SCU_IPC_LINCROFT] = {
83 		.ipc_base = 0xff11c000,
84 		.i2c_base = 0xff12b000,
85 		.ipc_len = 0x100,
86 		.i2c_len = 0x10,
87 		.irq_mode = 0,
88 	},
89 	[SCU_IPC_PENWELL] = {
90 		.ipc_base = 0xff11c000,
91 		.i2c_base = 0xff12b000,
92 		.ipc_len = 0x100,
93 		.i2c_len = 0x10,
94 		.irq_mode = 1,
95 	},
96 	[SCU_IPC_CLOVERVIEW] = {
97 		.ipc_base = 0xff11c000,
98 		.i2c_base = 0xff12b000,
99 		.ipc_len = 0x100,
100 		.i2c_len = 0x10,
101 		.irq_mode = 1,
102 	},
103 	[SCU_IPC_TANGIER] = {
104 		.ipc_base = 0xff009000,
105 		.i2c_base  = 0xff00d000,
106 		.ipc_len  = 0x100,
107 		.i2c_len = 0x10,
108 		.irq_mode = 0,
109 	},
110 };
111 
112 static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id);
113 static void ipc_remove(struct pci_dev *pdev);
114 
115 struct intel_scu_ipc_dev {
116 	struct pci_dev *pdev;
117 	void __iomem *ipc_base;
118 	void __iomem *i2c_base;
119 	struct completion cmd_complete;
120 	u8 irq_mode;
121 };
122 
123 static struct intel_scu_ipc_dev  ipcdev; /* Only one for now */
124 
125 static int platform;		/* Platform type */
126 
127 /*
128  * IPC Read Buffer (Read Only):
129  * 16 byte buffer for receiving data from SCU, if IPC command
130  * processing results in response data
131  */
132 #define IPC_READ_BUFFER		0x90
133 
134 #define IPC_I2C_CNTRL_ADDR	0
135 #define I2C_DATA_ADDR		0x04
136 
137 static DEFINE_MUTEX(ipclock); /* lock used to prevent multiple call to SCU */
138 
139 /*
140  * Command Register (Write Only):
141  * A write to this register results in an interrupt to the SCU core processor
142  * Format:
143  * |rfu2(8) | size(8) | command id(4) | rfu1(3) | ioc(1) | command(8)|
144  */
145 static inline void ipc_command(u32 cmd) /* Send ipc command */
146 {
147 	if (ipcdev.irq_mode) {
148 		reinit_completion(&ipcdev.cmd_complete);
149 		writel(cmd | IPC_IOC, ipcdev.ipc_base);
150 	}
151 	writel(cmd, ipcdev.ipc_base);
152 }
153 
154 /*
155  * IPC Write Buffer (Write Only):
156  * 16-byte buffer for sending data associated with IPC command to
157  * SCU. Size of the data is specified in the IPC_COMMAND_REG register
158  */
159 static inline void ipc_data_writel(u32 data, u32 offset) /* Write ipc data */
160 {
161 	writel(data, ipcdev.ipc_base + 0x80 + offset);
162 }
163 
164 /*
165  * Status Register (Read Only):
166  * Driver will read this register to get the ready/busy status of the IPC
167  * block and error status of the IPC command that was just processed by SCU
168  * Format:
169  * |rfu3(8)|error code(8)|initiator id(8)|cmd id(4)|rfu1(2)|error(1)|busy(1)|
170  */
171 
172 static inline u8 ipc_read_status(void)
173 {
174 	return __raw_readl(ipcdev.ipc_base + 0x04);
175 }
176 
177 static inline u8 ipc_data_readb(u32 offset) /* Read ipc byte data */
178 {
179 	return readb(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
180 }
181 
182 static inline u32 ipc_data_readl(u32 offset) /* Read ipc u32 data */
183 {
184 	return readl(ipcdev.ipc_base + IPC_READ_BUFFER + offset);
185 }
186 
187 static inline int busy_loop(void) /* Wait till scu status is busy */
188 {
189 	u32 status = 0;
190 	u32 loop_count = 0;
191 
192 	status = ipc_read_status();
193 	while (status & 1) {
194 		udelay(1); /* scu processing time is in few u secods */
195 		status = ipc_read_status();
196 		loop_count++;
197 		/* break if scu doesn't reset busy bit after huge retry */
198 		if (loop_count > 100000) {
199 			dev_err(&ipcdev.pdev->dev, "IPC timed out");
200 			return -ETIMEDOUT;
201 		}
202 	}
203 	if ((status >> 1) & 1)
204 		return -EIO;
205 
206 	return 0;
207 }
208 
209 /* Wait till ipc ioc interrupt is received or timeout in 3 HZ */
210 static inline int ipc_wait_for_interrupt(void)
211 {
212 	int status;
213 
214 	if (!wait_for_completion_timeout(&ipcdev.cmd_complete, 3 * HZ)) {
215 		struct device *dev = &ipcdev.pdev->dev;
216 		dev_err(dev, "IPC timed out\n");
217 		return -ETIMEDOUT;
218 	}
219 
220 	status = ipc_read_status();
221 
222 	if ((status >> 1) & 1)
223 		return -EIO;
224 
225 	return 0;
226 }
227 
228 int intel_scu_ipc_check_status(void)
229 {
230 	return ipcdev.irq_mode ? ipc_wait_for_interrupt() : busy_loop();
231 }
232 
233 /* Read/Write power control(PMIC in Langwell, MSIC in PenWell) registers */
234 static int pwr_reg_rdwr(u16 *addr, u8 *data, u32 count, u32 op, u32 id)
235 {
236 	int nc;
237 	u32 offset = 0;
238 	int err;
239 	u8 cbuf[IPC_WWBUF_SIZE] = { };
240 	u32 *wbuf = (u32 *)&cbuf;
241 
242 	mutex_lock(&ipclock);
243 
244 	memset(cbuf, 0, sizeof(cbuf));
245 
246 	if (ipcdev.pdev == NULL) {
247 		mutex_unlock(&ipclock);
248 		return -ENODEV;
249 	}
250 
251 	for (nc = 0; nc < count; nc++, offset += 2) {
252 		cbuf[offset] = addr[nc];
253 		cbuf[offset + 1] = addr[nc] >> 8;
254 	}
255 
256 	if (id == IPC_CMD_PCNTRL_R) {
257 		for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
258 			ipc_data_writel(wbuf[nc], offset);
259 		ipc_command((count*2) << 16 |  id << 12 | 0 << 8 | op);
260 	} else if (id == IPC_CMD_PCNTRL_W) {
261 		for (nc = 0; nc < count; nc++, offset += 1)
262 			cbuf[offset] = data[nc];
263 		for (nc = 0, offset = 0; nc < count; nc++, offset += 4)
264 			ipc_data_writel(wbuf[nc], offset);
265 		ipc_command((count*3) << 16 |  id << 12 | 0 << 8 | op);
266 	} else if (id == IPC_CMD_PCNTRL_M) {
267 		cbuf[offset] = data[0];
268 		cbuf[offset + 1] = data[1];
269 		ipc_data_writel(wbuf[0], 0); /* Write wbuff */
270 		ipc_command(4 << 16 |  id << 12 | 0 << 8 | op);
271 	}
272 
273 	err = intel_scu_ipc_check_status();
274 	if (!err && id == IPC_CMD_PCNTRL_R) { /* Read rbuf */
275 		/* Workaround: values are read as 0 without memcpy_fromio */
276 		memcpy_fromio(cbuf, ipcdev.ipc_base + 0x90, 16);
277 		for (nc = 0; nc < count; nc++)
278 			data[nc] = ipc_data_readb(nc);
279 	}
280 	mutex_unlock(&ipclock);
281 	return err;
282 }
283 
284 /**
285  *	intel_scu_ipc_ioread8		-	read a word via the SCU
286  *	@addr: register on SCU
287  *	@data: return pointer for read byte
288  *
289  *	Read a single register. Returns 0 on success or an error code. All
290  *	locking between SCU accesses is handled for the caller.
291  *
292  *	This function may sleep.
293  */
294 int intel_scu_ipc_ioread8(u16 addr, u8 *data)
295 {
296 	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
297 }
298 EXPORT_SYMBOL(intel_scu_ipc_ioread8);
299 
300 /**
301  *	intel_scu_ipc_ioread16		-	read a word via the SCU
302  *	@addr: register on SCU
303  *	@data: return pointer for read word
304  *
305  *	Read a register pair. Returns 0 on success or an error code. All
306  *	locking between SCU accesses is handled for the caller.
307  *
308  *	This function may sleep.
309  */
310 int intel_scu_ipc_ioread16(u16 addr, u16 *data)
311 {
312 	u16 x[2] = {addr, addr + 1 };
313 	return pwr_reg_rdwr(x, (u8 *)data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
314 }
315 EXPORT_SYMBOL(intel_scu_ipc_ioread16);
316 
317 /**
318  *	intel_scu_ipc_ioread32		-	read a dword via the SCU
319  *	@addr: register on SCU
320  *	@data: return pointer for read dword
321  *
322  *	Read four registers. Returns 0 on success or an error code. All
323  *	locking between SCU accesses is handled for the caller.
324  *
325  *	This function may sleep.
326  */
327 int intel_scu_ipc_ioread32(u16 addr, u32 *data)
328 {
329 	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
330 	return pwr_reg_rdwr(x, (u8 *)data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
331 }
332 EXPORT_SYMBOL(intel_scu_ipc_ioread32);
333 
334 /**
335  *	intel_scu_ipc_iowrite8		-	write a byte via the SCU
336  *	@addr: register on SCU
337  *	@data: byte to write
338  *
339  *	Write a single register. Returns 0 on success or an error code. All
340  *	locking between SCU accesses is handled for the caller.
341  *
342  *	This function may sleep.
343  */
344 int intel_scu_ipc_iowrite8(u16 addr, u8 data)
345 {
346 	return pwr_reg_rdwr(&addr, &data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
347 }
348 EXPORT_SYMBOL(intel_scu_ipc_iowrite8);
349 
350 /**
351  *	intel_scu_ipc_iowrite16		-	write a word via the SCU
352  *	@addr: register on SCU
353  *	@data: word to write
354  *
355  *	Write two registers. Returns 0 on success or an error code. All
356  *	locking between SCU accesses is handled for the caller.
357  *
358  *	This function may sleep.
359  */
360 int intel_scu_ipc_iowrite16(u16 addr, u16 data)
361 {
362 	u16 x[2] = {addr, addr + 1 };
363 	return pwr_reg_rdwr(x, (u8 *)&data, 2, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
364 }
365 EXPORT_SYMBOL(intel_scu_ipc_iowrite16);
366 
367 /**
368  *	intel_scu_ipc_iowrite32		-	write a dword via the SCU
369  *	@addr: register on SCU
370  *	@data: dword to write
371  *
372  *	Write four registers. Returns 0 on success or an error code. All
373  *	locking between SCU accesses is handled for the caller.
374  *
375  *	This function may sleep.
376  */
377 int intel_scu_ipc_iowrite32(u16 addr, u32 data)
378 {
379 	u16 x[4] = {addr, addr + 1, addr + 2, addr + 3};
380 	return pwr_reg_rdwr(x, (u8 *)&data, 4, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
381 }
382 EXPORT_SYMBOL(intel_scu_ipc_iowrite32);
383 
384 /**
385  *	intel_scu_ipc_readvv		-	read a set of registers
386  *	@addr: register list
387  *	@data: bytes to return
388  *	@len: length of array
389  *
390  *	Read registers. Returns 0 on success or an error code. All
391  *	locking between SCU accesses is handled for the caller.
392  *
393  *	The largest array length permitted by the hardware is 5 items.
394  *
395  *	This function may sleep.
396  */
397 int intel_scu_ipc_readv(u16 *addr, u8 *data, int len)
398 {
399 	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_R);
400 }
401 EXPORT_SYMBOL(intel_scu_ipc_readv);
402 
403 /**
404  *	intel_scu_ipc_writev		-	write a set of registers
405  *	@addr: register list
406  *	@data: bytes to write
407  *	@len: length of array
408  *
409  *	Write registers. Returns 0 on success or an error code. All
410  *	locking between SCU accesses is handled for the caller.
411  *
412  *	The largest array length permitted by the hardware is 5 items.
413  *
414  *	This function may sleep.
415  *
416  */
417 int intel_scu_ipc_writev(u16 *addr, u8 *data, int len)
418 {
419 	return pwr_reg_rdwr(addr, data, len, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_W);
420 }
421 EXPORT_SYMBOL(intel_scu_ipc_writev);
422 
423 
424 /**
425  *	intel_scu_ipc_update_register	-	r/m/w a register
426  *	@addr: register address
427  *	@bits: bits to update
428  *	@mask: mask of bits to update
429  *
430  *	Read-modify-write power control unit register. The first data argument
431  *	must be register value and second is mask value
432  *	mask is a bitmap that indicates which bits to update.
433  *	0 = masked. Don't modify this bit, 1 = modify this bit.
434  *	returns 0 on success or an error code.
435  *
436  *	This function may sleep. Locking between SCU accesses is handled
437  *	for the caller.
438  */
439 int intel_scu_ipc_update_register(u16 addr, u8 bits, u8 mask)
440 {
441 	u8 data[2] = { bits, mask };
442 	return pwr_reg_rdwr(&addr, data, 1, IPCMSG_PCNTRL, IPC_CMD_PCNTRL_M);
443 }
444 EXPORT_SYMBOL(intel_scu_ipc_update_register);
445 
446 /**
447  *	intel_scu_ipc_simple_command	-	send a simple command
448  *	@cmd: command
449  *	@sub: sub type
450  *
451  *	Issue a simple command to the SCU. Do not use this interface if
452  *	you must then access data as any data values may be overwritten
453  *	by another SCU access by the time this function returns.
454  *
455  *	This function may sleep. Locking for SCU accesses is handled for
456  *	the caller.
457  */
458 int intel_scu_ipc_simple_command(int cmd, int sub)
459 {
460 	int err;
461 
462 	mutex_lock(&ipclock);
463 	if (ipcdev.pdev == NULL) {
464 		mutex_unlock(&ipclock);
465 		return -ENODEV;
466 	}
467 	ipc_command(sub << 12 | cmd);
468 	err = intel_scu_ipc_check_status();
469 	mutex_unlock(&ipclock);
470 	return err;
471 }
472 EXPORT_SYMBOL(intel_scu_ipc_simple_command);
473 
474 /**
475  *	intel_scu_ipc_command	-	command with data
476  *	@cmd: command
477  *	@sub: sub type
478  *	@in: input data
479  *	@inlen: input length in dwords
480  *	@out: output data
481  *	@outlein: output length in dwords
482  *
483  *	Issue a command to the SCU which involves data transfers. Do the
484  *	data copies under the lock but leave it for the caller to interpret
485  */
486 
487 int intel_scu_ipc_command(int cmd, int sub, u32 *in, int inlen,
488 							u32 *out, int outlen)
489 {
490 	int i, err;
491 
492 	mutex_lock(&ipclock);
493 	if (ipcdev.pdev == NULL) {
494 		mutex_unlock(&ipclock);
495 		return -ENODEV;
496 	}
497 
498 	for (i = 0; i < inlen; i++)
499 		ipc_data_writel(*in++, 4 * i);
500 
501 	ipc_command((inlen << 16) | (sub << 12) | cmd);
502 	err = intel_scu_ipc_check_status();
503 
504 	if (!err) {
505 		for (i = 0; i < outlen; i++)
506 			*out++ = ipc_data_readl(4 * i);
507 	}
508 
509 	mutex_unlock(&ipclock);
510 	return err;
511 }
512 EXPORT_SYMBOL(intel_scu_ipc_command);
513 
514 /*I2C commands */
515 #define IPC_I2C_WRITE 1 /* I2C Write command */
516 #define IPC_I2C_READ  2 /* I2C Read command */
517 
518 /**
519  *	intel_scu_ipc_i2c_cntrl		-	I2C read/write operations
520  *	@addr: I2C address + command bits
521  *	@data: data to read/write
522  *
523  *	Perform an an I2C read/write operation via the SCU. All locking is
524  *	handled for the caller. This function may sleep.
525  *
526  *	Returns an error code or 0 on success.
527  *
528  *	This has to be in the IPC driver for the locking.
529  */
530 int intel_scu_ipc_i2c_cntrl(u32 addr, u32 *data)
531 {
532 	u32 cmd = 0;
533 
534 	mutex_lock(&ipclock);
535 	if (ipcdev.pdev == NULL) {
536 		mutex_unlock(&ipclock);
537 		return -ENODEV;
538 	}
539 	cmd = (addr >> 24) & 0xFF;
540 	if (cmd == IPC_I2C_READ) {
541 		writel(addr, ipcdev.i2c_base + IPC_I2C_CNTRL_ADDR);
542 		/* Write not getting updated without delay */
543 		mdelay(1);
544 		*data = readl(ipcdev.i2c_base + I2C_DATA_ADDR);
545 	} else if (cmd == IPC_I2C_WRITE) {
546 		writel(*data, ipcdev.i2c_base + I2C_DATA_ADDR);
547 		mdelay(1);
548 		writel(addr, ipcdev.i2c_base + IPC_I2C_CNTRL_ADDR);
549 	} else {
550 		dev_err(&ipcdev.pdev->dev,
551 			"intel_scu_ipc: I2C INVALID_CMD = 0x%x\n", cmd);
552 
553 		mutex_unlock(&ipclock);
554 		return -EIO;
555 	}
556 	mutex_unlock(&ipclock);
557 	return 0;
558 }
559 EXPORT_SYMBOL(intel_scu_ipc_i2c_cntrl);
560 
561 /*
562  * Interrupt handler gets called when ioc bit of IPC_COMMAND_REG set to 1
563  * When ioc bit is set to 1, caller api must wait for interrupt handler called
564  * which in turn unlocks the caller api. Currently this is not used
565  *
566  * This is edge triggered so we need take no action to clear anything
567  */
568 static irqreturn_t ioc(int irq, void *dev_id)
569 {
570 	if (ipcdev.irq_mode)
571 		complete(&ipcdev.cmd_complete);
572 
573 	return IRQ_HANDLED;
574 }
575 
576 /**
577  *	ipc_probe	-	probe an Intel SCU IPC
578  *	@dev: the PCI device matching
579  *	@id: entry in the match table
580  *
581  *	Enable and install an intel SCU IPC. This appears in the PCI space
582  *	but uses some hard coded addresses as well.
583  */
584 static int ipc_probe(struct pci_dev *dev, const struct pci_device_id *id)
585 {
586 	int err, pid;
587 	struct intel_scu_ipc_pdata_t *pdata;
588 	resource_size_t pci_resource;
589 
590 	if (ipcdev.pdev)		/* We support only one SCU */
591 		return -EBUSY;
592 
593 	pid = id->driver_data;
594 	pdata = &intel_scu_ipc_pdata[pid];
595 
596 	ipcdev.pdev = pci_dev_get(dev);
597 	ipcdev.irq_mode = pdata->irq_mode;
598 
599 	err = pci_enable_device(dev);
600 	if (err)
601 		return err;
602 
603 	err = pci_request_regions(dev, "intel_scu_ipc");
604 	if (err)
605 		return err;
606 
607 	pci_resource = pci_resource_start(dev, 0);
608 	if (!pci_resource)
609 		return -ENOMEM;
610 
611 	init_completion(&ipcdev.cmd_complete);
612 
613 	if (request_irq(dev->irq, ioc, 0, "intel_scu_ipc", &ipcdev))
614 		return -EBUSY;
615 
616 	ipcdev.ipc_base = ioremap_nocache(pdata->ipc_base, pdata->ipc_len);
617 	if (!ipcdev.ipc_base)
618 		return -ENOMEM;
619 
620 	ipcdev.i2c_base = ioremap_nocache(pdata->i2c_base, pdata->i2c_len);
621 	if (!ipcdev.i2c_base) {
622 		iounmap(ipcdev.ipc_base);
623 		return -ENOMEM;
624 	}
625 
626 	intel_scu_devices_create();
627 
628 	return 0;
629 }
630 
631 /**
632  *	ipc_remove	-	remove a bound IPC device
633  *	@pdev: PCI device
634  *
635  *	In practice the SCU is not removable but this function is also
636  *	called for each device on a module unload or cleanup which is the
637  *	path that will get used.
638  *
639  *	Free up the mappings and release the PCI resources
640  */
641 static void ipc_remove(struct pci_dev *pdev)
642 {
643 	free_irq(pdev->irq, &ipcdev);
644 	pci_release_regions(pdev);
645 	pci_dev_put(ipcdev.pdev);
646 	iounmap(ipcdev.ipc_base);
647 	iounmap(ipcdev.i2c_base);
648 	ipcdev.pdev = NULL;
649 	intel_scu_devices_destroy();
650 }
651 
652 static DEFINE_PCI_DEVICE_TABLE(pci_ids) = {
653 	{PCI_VDEVICE(INTEL, 0x082a), SCU_IPC_LINCROFT},
654 	{PCI_VDEVICE(INTEL, 0x080e), SCU_IPC_PENWELL},
655 	{PCI_VDEVICE(INTEL, 0x08ea), SCU_IPC_CLOVERVIEW},
656 	{PCI_VDEVICE(INTEL, 0x11a0), SCU_IPC_TANGIER},
657 	{ 0,}
658 };
659 MODULE_DEVICE_TABLE(pci, pci_ids);
660 
661 static struct pci_driver ipc_driver = {
662 	.name = "intel_scu_ipc",
663 	.id_table = pci_ids,
664 	.probe = ipc_probe,
665 	.remove = ipc_remove,
666 };
667 
668 
669 static int __init intel_scu_ipc_init(void)
670 {
671 	platform = intel_mid_identify_cpu();
672 	if (platform == 0)
673 		return -ENODEV;
674 	return  pci_register_driver(&ipc_driver);
675 }
676 
677 static void __exit intel_scu_ipc_exit(void)
678 {
679 	pci_unregister_driver(&ipc_driver);
680 }
681 
682 MODULE_AUTHOR("Sreedhara DS <sreedhara.ds@intel.com>");
683 MODULE_DESCRIPTION("Intel SCU IPC driver");
684 MODULE_LICENSE("GPL");
685 
686 module_init(intel_scu_ipc_init);
687 module_exit(intel_scu_ipc_exit);
688