xref: /openbmc/linux/drivers/i2c/busses/i2c-i801.c (revision 2022ca0a)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3     Copyright (c) 1998 - 2002  Frodo Looijaard <frodol@dds.nl>,
4     Philip Edelbrock <phil@netroedge.com>, and Mark D. Studebaker
5     <mdsxyz123@yahoo.com>
6     Copyright (C) 2007 - 2014  Jean Delvare <jdelvare@suse.de>
7     Copyright (C) 2010         Intel Corporation,
8                                David Woodhouse <dwmw2@infradead.org>
9 
10 */
11 
12 /*
13  * Supports the following Intel I/O Controller Hubs (ICH):
14  *
15  *					I/O			Block	I2C
16  *					region	SMBus	Block	proc.	block
17  * Chip name			PCI ID	size	PEC	buffer	call	read
18  * ---------------------------------------------------------------------------
19  * 82801AA (ICH)		0x2413	16	no	no	no	no
20  * 82801AB (ICH0)		0x2423	16	no	no	no	no
21  * 82801BA (ICH2)		0x2443	16	no	no	no	no
22  * 82801CA (ICH3)		0x2483	32	soft	no	no	no
23  * 82801DB (ICH4)		0x24c3	32	hard	yes	no	no
24  * 82801E (ICH5)		0x24d3	32	hard	yes	yes	yes
25  * 6300ESB			0x25a4	32	hard	yes	yes	yes
26  * 82801F (ICH6)		0x266a	32	hard	yes	yes	yes
27  * 6310ESB/6320ESB		0x269b	32	hard	yes	yes	yes
28  * 82801G (ICH7)		0x27da	32	hard	yes	yes	yes
29  * 82801H (ICH8)		0x283e	32	hard	yes	yes	yes
30  * 82801I (ICH9)		0x2930	32	hard	yes	yes	yes
31  * EP80579 (Tolapai)		0x5032	32	hard	yes	yes	yes
32  * ICH10			0x3a30	32	hard	yes	yes	yes
33  * ICH10			0x3a60	32	hard	yes	yes	yes
34  * 5/3400 Series (PCH)		0x3b30	32	hard	yes	yes	yes
35  * 6 Series (PCH)		0x1c22	32	hard	yes	yes	yes
36  * Patsburg (PCH)		0x1d22	32	hard	yes	yes	yes
37  * Patsburg (PCH) IDF		0x1d70	32	hard	yes	yes	yes
38  * Patsburg (PCH) IDF		0x1d71	32	hard	yes	yes	yes
39  * Patsburg (PCH) IDF		0x1d72	32	hard	yes	yes	yes
40  * DH89xxCC (PCH)		0x2330	32	hard	yes	yes	yes
41  * Panther Point (PCH)		0x1e22	32	hard	yes	yes	yes
42  * Lynx Point (PCH)		0x8c22	32	hard	yes	yes	yes
43  * Lynx Point-LP (PCH)		0x9c22	32	hard	yes	yes	yes
44  * Avoton (SOC)			0x1f3c	32	hard	yes	yes	yes
45  * Wellsburg (PCH)		0x8d22	32	hard	yes	yes	yes
46  * Wellsburg (PCH) MS		0x8d7d	32	hard	yes	yes	yes
47  * Wellsburg (PCH) MS		0x8d7e	32	hard	yes	yes	yes
48  * Wellsburg (PCH) MS		0x8d7f	32	hard	yes	yes	yes
49  * Coleto Creek (PCH)		0x23b0	32	hard	yes	yes	yes
50  * Wildcat Point (PCH)		0x8ca2	32	hard	yes	yes	yes
51  * Wildcat Point-LP (PCH)	0x9ca2	32	hard	yes	yes	yes
52  * BayTrail (SOC)		0x0f12	32	hard	yes	yes	yes
53  * Braswell (SOC)		0x2292	32	hard	yes	yes	yes
54  * Sunrise Point-H (PCH) 	0xa123  32	hard	yes	yes	yes
55  * Sunrise Point-LP (PCH)	0x9d23	32	hard	yes	yes	yes
56  * DNV (SOC)			0x19df	32	hard	yes	yes	yes
57  * Broxton (SOC)		0x5ad4	32	hard	yes	yes	yes
58  * Lewisburg (PCH)		0xa1a3	32	hard	yes	yes	yes
59  * Lewisburg Supersku (PCH)	0xa223	32	hard	yes	yes	yes
60  * Kaby Lake PCH-H (PCH)	0xa2a3	32	hard	yes	yes	yes
61  * Gemini Lake (SOC)		0x31d4	32	hard	yes	yes	yes
62  * Cannon Lake-H (PCH)		0xa323	32	hard	yes	yes	yes
63  * Cannon Lake-LP (PCH)		0x9da3	32	hard	yes	yes	yes
64  * Cedar Fork (PCH)		0x18df	32	hard	yes	yes	yes
65  * Ice Lake-LP (PCH)		0x34a3	32	hard	yes	yes	yes
66  * Comet Lake (PCH)		0x02a3	32	hard	yes	yes	yes
67  * Elkhart Lake (PCH)		0x4b23	32	hard	yes	yes	yes
68  * Tiger Lake-LP (PCH)		0xa0a3	32	hard	yes	yes	yes
69  *
70  * Features supported by this driver:
71  * Software PEC				no
72  * Hardware PEC				yes
73  * Block buffer				yes
74  * Block process call transaction	yes
75  * I2C block read transaction		yes (doesn't use the block buffer)
76  * Slave mode				no
77  * SMBus Host Notify			yes
78  * Interrupt processing			yes
79  *
80  * See the file Documentation/i2c/busses/i2c-i801.rst for details.
81  */
82 
83 #include <linux/interrupt.h>
84 #include <linux/module.h>
85 #include <linux/pci.h>
86 #include <linux/kernel.h>
87 #include <linux/stddef.h>
88 #include <linux/delay.h>
89 #include <linux/ioport.h>
90 #include <linux/init.h>
91 #include <linux/i2c.h>
92 #include <linux/i2c-smbus.h>
93 #include <linux/acpi.h>
94 #include <linux/io.h>
95 #include <linux/dmi.h>
96 #include <linux/slab.h>
97 #include <linux/string.h>
98 #include <linux/wait.h>
99 #include <linux/err.h>
100 #include <linux/platform_device.h>
101 #include <linux/platform_data/itco_wdt.h>
102 #include <linux/pm_runtime.h>
103 
104 #if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
105 #include <linux/gpio/machine.h>
106 #include <linux/platform_data/i2c-mux-gpio.h>
107 #endif
108 
109 /* I801 SMBus address offsets */
110 #define SMBHSTSTS(p)	(0 + (p)->smba)
111 #define SMBHSTCNT(p)	(2 + (p)->smba)
112 #define SMBHSTCMD(p)	(3 + (p)->smba)
113 #define SMBHSTADD(p)	(4 + (p)->smba)
114 #define SMBHSTDAT0(p)	(5 + (p)->smba)
115 #define SMBHSTDAT1(p)	(6 + (p)->smba)
116 #define SMBBLKDAT(p)	(7 + (p)->smba)
117 #define SMBPEC(p)	(8 + (p)->smba)		/* ICH3 and later */
118 #define SMBAUXSTS(p)	(12 + (p)->smba)	/* ICH4 and later */
119 #define SMBAUXCTL(p)	(13 + (p)->smba)	/* ICH4 and later */
120 #define SMBSLVSTS(p)	(16 + (p)->smba)	/* ICH3 and later */
121 #define SMBSLVCMD(p)	(17 + (p)->smba)	/* ICH3 and later */
122 #define SMBNTFDADD(p)	(20 + (p)->smba)	/* ICH3 and later */
123 
124 /* PCI Address Constants */
125 #define SMBBAR		4
126 #define SMBPCICTL	0x004
127 #define SMBPCISTS	0x006
128 #define SMBHSTCFG	0x040
129 #define TCOBASE		0x050
130 #define TCOCTL		0x054
131 
132 #define ACPIBASE		0x040
133 #define ACPIBASE_SMI_OFF	0x030
134 #define ACPICTRL		0x044
135 #define ACPICTRL_EN		0x080
136 
137 #define SBREG_BAR		0x10
138 #define SBREG_SMBCTRL		0xc6000c
139 #define SBREG_SMBCTRL_DNV	0xcf000c
140 
141 /* Host status bits for SMBPCISTS */
142 #define SMBPCISTS_INTS		BIT(3)
143 
144 /* Control bits for SMBPCICTL */
145 #define SMBPCICTL_INTDIS	BIT(10)
146 
147 /* Host configuration bits for SMBHSTCFG */
148 #define SMBHSTCFG_HST_EN	BIT(0)
149 #define SMBHSTCFG_SMB_SMI_EN	BIT(1)
150 #define SMBHSTCFG_I2C_EN	BIT(2)
151 #define SMBHSTCFG_SPD_WD	BIT(4)
152 
153 /* TCO configuration bits for TCOCTL */
154 #define TCOCTL_EN		BIT(8)
155 
156 /* Auxiliary status register bits, ICH4+ only */
157 #define SMBAUXSTS_CRCE		BIT(0)
158 #define SMBAUXSTS_STCO		BIT(1)
159 
160 /* Auxiliary control register bits, ICH4+ only */
161 #define SMBAUXCTL_CRC		BIT(0)
162 #define SMBAUXCTL_E32B		BIT(1)
163 
164 /* Other settings */
165 #define MAX_RETRIES		400
166 
167 /* I801 command constants */
168 #define I801_QUICK		0x00
169 #define I801_BYTE		0x04
170 #define I801_BYTE_DATA		0x08
171 #define I801_WORD_DATA		0x0C
172 #define I801_PROC_CALL		0x10	/* unimplemented */
173 #define I801_BLOCK_DATA		0x14
174 #define I801_I2C_BLOCK_DATA	0x18	/* ICH5 and later */
175 #define I801_BLOCK_PROC_CALL	0x1C
176 
177 /* I801 Host Control register bits */
178 #define SMBHSTCNT_INTREN	BIT(0)
179 #define SMBHSTCNT_KILL		BIT(1)
180 #define SMBHSTCNT_LAST_BYTE	BIT(5)
181 #define SMBHSTCNT_START		BIT(6)
182 #define SMBHSTCNT_PEC_EN	BIT(7)	/* ICH3 and later */
183 
184 /* I801 Hosts Status register bits */
185 #define SMBHSTSTS_BYTE_DONE	BIT(7)
186 #define SMBHSTSTS_INUSE_STS	BIT(6)
187 #define SMBHSTSTS_SMBALERT_STS	BIT(5)
188 #define SMBHSTSTS_FAILED	BIT(4)
189 #define SMBHSTSTS_BUS_ERR	BIT(3)
190 #define SMBHSTSTS_DEV_ERR	BIT(2)
191 #define SMBHSTSTS_INTR		BIT(1)
192 #define SMBHSTSTS_HOST_BUSY	BIT(0)
193 
194 /* Host Notify Status register bits */
195 #define SMBSLVSTS_HST_NTFY_STS	BIT(0)
196 
197 /* Host Notify Command register bits */
198 #define SMBSLVCMD_HST_NTFY_INTREN	BIT(0)
199 
200 #define STATUS_ERROR_FLAGS	(SMBHSTSTS_FAILED | SMBHSTSTS_BUS_ERR | \
201 				 SMBHSTSTS_DEV_ERR)
202 
203 #define STATUS_FLAGS		(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR | \
204 				 STATUS_ERROR_FLAGS)
205 
206 /* Older devices have their ID defined in <linux/pci_ids.h> */
207 #define PCI_DEVICE_ID_INTEL_COMETLAKE_SMBUS		0x02a3
208 #define PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS		0x0f12
209 #define PCI_DEVICE_ID_INTEL_CDF_SMBUS			0x18df
210 #define PCI_DEVICE_ID_INTEL_DNV_SMBUS			0x19df
211 #define PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS		0x1c22
212 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS		0x1d22
213 /* Patsburg also has three 'Integrated Device Function' SMBus controllers */
214 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0		0x1d70
215 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1		0x1d71
216 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2		0x1d72
217 #define PCI_DEVICE_ID_INTEL_PANTHERPOINT_SMBUS		0x1e22
218 #define PCI_DEVICE_ID_INTEL_AVOTON_SMBUS		0x1f3c
219 #define PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS		0x2292
220 #define PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS		0x2330
221 #define PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS		0x23b0
222 #define PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS		0x31d4
223 #define PCI_DEVICE_ID_INTEL_ICELAKE_LP_SMBUS		0x34a3
224 #define PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS		0x3b30
225 #define PCI_DEVICE_ID_INTEL_ELKHART_LAKE_SMBUS		0x4b23
226 #define PCI_DEVICE_ID_INTEL_BROXTON_SMBUS		0x5ad4
227 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS		0x8c22
228 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS		0x8ca2
229 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS		0x8d22
230 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS0		0x8d7d
231 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1		0x8d7e
232 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2		0x8d7f
233 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_SMBUS		0x9c22
234 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS	0x9ca2
235 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS	0x9d23
236 #define PCI_DEVICE_ID_INTEL_CANNONLAKE_LP_SMBUS		0x9da3
237 #define PCI_DEVICE_ID_INTEL_TIGERLAKE_LP_SMBUS		0xa0a3
238 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS	0xa123
239 #define PCI_DEVICE_ID_INTEL_LEWISBURG_SMBUS		0xa1a3
240 #define PCI_DEVICE_ID_INTEL_LEWISBURG_SSKU_SMBUS	0xa223
241 #define PCI_DEVICE_ID_INTEL_KABYLAKE_PCH_H_SMBUS	0xa2a3
242 #define PCI_DEVICE_ID_INTEL_CANNONLAKE_H_SMBUS		0xa323
243 
244 struct i801_mux_config {
245 	char *gpio_chip;
246 	unsigned values[3];
247 	int n_values;
248 	unsigned classes[3];
249 	unsigned gpios[2];		/* Relative to gpio_chip->base */
250 	int n_gpios;
251 };
252 
253 struct i801_priv {
254 	struct i2c_adapter adapter;
255 	unsigned long smba;
256 	unsigned char original_hstcfg;
257 	unsigned char original_slvcmd;
258 	struct pci_dev *pci_dev;
259 	unsigned int features;
260 
261 	/* isr processing */
262 	wait_queue_head_t waitq;
263 	u8 status;
264 
265 	/* Command state used by isr for byte-by-byte block transactions */
266 	u8 cmd;
267 	bool is_read;
268 	int count;
269 	int len;
270 	u8 *data;
271 
272 #if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
273 	const struct i801_mux_config *mux_drvdata;
274 	struct platform_device *mux_pdev;
275 	struct gpiod_lookup_table *lookup;
276 #endif
277 	struct platform_device *tco_pdev;
278 
279 	/*
280 	 * If set to true the host controller registers are reserved for
281 	 * ACPI AML use. Protected by acpi_lock.
282 	 */
283 	bool acpi_reserved;
284 	struct mutex acpi_lock;
285 };
286 
287 #define FEATURE_SMBUS_PEC	BIT(0)
288 #define FEATURE_BLOCK_BUFFER	BIT(1)
289 #define FEATURE_BLOCK_PROC	BIT(2)
290 #define FEATURE_I2C_BLOCK_READ	BIT(3)
291 #define FEATURE_IRQ		BIT(4)
292 #define FEATURE_HOST_NOTIFY	BIT(5)
293 /* Not really a feature, but it's convenient to handle it as such */
294 #define FEATURE_IDF		BIT(15)
295 #define FEATURE_TCO_SPT		BIT(16)
296 #define FEATURE_TCO_CNL		BIT(17)
297 
298 static const char *i801_feature_names[] = {
299 	"SMBus PEC",
300 	"Block buffer",
301 	"Block process call",
302 	"I2C block read",
303 	"Interrupt",
304 	"SMBus Host Notify",
305 };
306 
307 static unsigned int disable_features;
308 module_param(disable_features, uint, S_IRUGO | S_IWUSR);
309 MODULE_PARM_DESC(disable_features, "Disable selected driver features:\n"
310 	"\t\t  0x01  disable SMBus PEC\n"
311 	"\t\t  0x02  disable the block buffer\n"
312 	"\t\t  0x08  disable the I2C block read functionality\n"
313 	"\t\t  0x10  don't use interrupts\n"
314 	"\t\t  0x20  disable SMBus Host Notify ");
315 
316 /* Make sure the SMBus host is ready to start transmitting.
317    Return 0 if it is, -EBUSY if it is not. */
318 static int i801_check_pre(struct i801_priv *priv)
319 {
320 	int status;
321 
322 	status = inb_p(SMBHSTSTS(priv));
323 	if (status & SMBHSTSTS_HOST_BUSY) {
324 		dev_err(&priv->pci_dev->dev, "SMBus is busy, can't use it!\n");
325 		return -EBUSY;
326 	}
327 
328 	status &= STATUS_FLAGS;
329 	if (status) {
330 		dev_dbg(&priv->pci_dev->dev, "Clearing status flags (%02x)\n",
331 			status);
332 		outb_p(status, SMBHSTSTS(priv));
333 		status = inb_p(SMBHSTSTS(priv)) & STATUS_FLAGS;
334 		if (status) {
335 			dev_err(&priv->pci_dev->dev,
336 				"Failed clearing status flags (%02x)\n",
337 				status);
338 			return -EBUSY;
339 		}
340 	}
341 
342 	/*
343 	 * Clear CRC status if needed.
344 	 * During normal operation, i801_check_post() takes care
345 	 * of it after every operation.  We do it here only in case
346 	 * the hardware was already in this state when the driver
347 	 * started.
348 	 */
349 	if (priv->features & FEATURE_SMBUS_PEC) {
350 		status = inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE;
351 		if (status) {
352 			dev_dbg(&priv->pci_dev->dev,
353 				"Clearing aux status flags (%02x)\n", status);
354 			outb_p(status, SMBAUXSTS(priv));
355 			status = inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE;
356 			if (status) {
357 				dev_err(&priv->pci_dev->dev,
358 					"Failed clearing aux status flags (%02x)\n",
359 					status);
360 				return -EBUSY;
361 			}
362 		}
363 	}
364 
365 	return 0;
366 }
367 
368 /*
369  * Convert the status register to an error code, and clear it.
370  * Note that status only contains the bits we want to clear, not the
371  * actual register value.
372  */
373 static int i801_check_post(struct i801_priv *priv, int status)
374 {
375 	int result = 0;
376 
377 	/*
378 	 * If the SMBus is still busy, we give up
379 	 * Note: This timeout condition only happens when using polling
380 	 * transactions.  For interrupt operation, NAK/timeout is indicated by
381 	 * DEV_ERR.
382 	 */
383 	if (unlikely(status < 0)) {
384 		dev_err(&priv->pci_dev->dev, "Transaction timeout\n");
385 		/* try to stop the current command */
386 		dev_dbg(&priv->pci_dev->dev, "Terminating the current operation\n");
387 		outb_p(inb_p(SMBHSTCNT(priv)) | SMBHSTCNT_KILL,
388 		       SMBHSTCNT(priv));
389 		usleep_range(1000, 2000);
390 		outb_p(inb_p(SMBHSTCNT(priv)) & (~SMBHSTCNT_KILL),
391 		       SMBHSTCNT(priv));
392 
393 		/* Check if it worked */
394 		status = inb_p(SMBHSTSTS(priv));
395 		if ((status & SMBHSTSTS_HOST_BUSY) ||
396 		    !(status & SMBHSTSTS_FAILED))
397 			dev_err(&priv->pci_dev->dev,
398 				"Failed terminating the transaction\n");
399 		outb_p(STATUS_FLAGS, SMBHSTSTS(priv));
400 		return -ETIMEDOUT;
401 	}
402 
403 	if (status & SMBHSTSTS_FAILED) {
404 		result = -EIO;
405 		dev_err(&priv->pci_dev->dev, "Transaction failed\n");
406 	}
407 	if (status & SMBHSTSTS_DEV_ERR) {
408 		/*
409 		 * This may be a PEC error, check and clear it.
410 		 *
411 		 * AUXSTS is handled differently from HSTSTS.
412 		 * For HSTSTS, i801_isr() or i801_wait_intr()
413 		 * has already cleared the error bits in hardware,
414 		 * and we are passed a copy of the original value
415 		 * in "status".
416 		 * For AUXSTS, the hardware register is left
417 		 * for us to handle here.
418 		 * This is asymmetric, slightly iffy, but safe,
419 		 * since all this code is serialized and the CRCE
420 		 * bit is harmless as long as it's cleared before
421 		 * the next operation.
422 		 */
423 		if ((priv->features & FEATURE_SMBUS_PEC) &&
424 		    (inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE)) {
425 			outb_p(SMBAUXSTS_CRCE, SMBAUXSTS(priv));
426 			result = -EBADMSG;
427 			dev_dbg(&priv->pci_dev->dev, "PEC error\n");
428 		} else {
429 			result = -ENXIO;
430 			dev_dbg(&priv->pci_dev->dev, "No response\n");
431 		}
432 	}
433 	if (status & SMBHSTSTS_BUS_ERR) {
434 		result = -EAGAIN;
435 		dev_dbg(&priv->pci_dev->dev, "Lost arbitration\n");
436 	}
437 
438 	/* Clear status flags except BYTE_DONE, to be cleared by caller */
439 	outb_p(status, SMBHSTSTS(priv));
440 
441 	return result;
442 }
443 
444 /* Wait for BUSY being cleared and either INTR or an error flag being set */
445 static int i801_wait_intr(struct i801_priv *priv)
446 {
447 	int timeout = 0;
448 	int status;
449 
450 	/* We will always wait for a fraction of a second! */
451 	do {
452 		usleep_range(250, 500);
453 		status = inb_p(SMBHSTSTS(priv));
454 	} while (((status & SMBHSTSTS_HOST_BUSY) ||
455 		  !(status & (STATUS_ERROR_FLAGS | SMBHSTSTS_INTR))) &&
456 		 (timeout++ < MAX_RETRIES));
457 
458 	if (timeout > MAX_RETRIES) {
459 		dev_dbg(&priv->pci_dev->dev, "INTR Timeout!\n");
460 		return -ETIMEDOUT;
461 	}
462 	return status & (STATUS_ERROR_FLAGS | SMBHSTSTS_INTR);
463 }
464 
465 /* Wait for either BYTE_DONE or an error flag being set */
466 static int i801_wait_byte_done(struct i801_priv *priv)
467 {
468 	int timeout = 0;
469 	int status;
470 
471 	/* We will always wait for a fraction of a second! */
472 	do {
473 		usleep_range(250, 500);
474 		status = inb_p(SMBHSTSTS(priv));
475 	} while (!(status & (STATUS_ERROR_FLAGS | SMBHSTSTS_BYTE_DONE)) &&
476 		 (timeout++ < MAX_RETRIES));
477 
478 	if (timeout > MAX_RETRIES) {
479 		dev_dbg(&priv->pci_dev->dev, "BYTE_DONE Timeout!\n");
480 		return -ETIMEDOUT;
481 	}
482 	return status & STATUS_ERROR_FLAGS;
483 }
484 
485 static int i801_transaction(struct i801_priv *priv, int xact)
486 {
487 	int status;
488 	int result;
489 	const struct i2c_adapter *adap = &priv->adapter;
490 
491 	result = i801_check_pre(priv);
492 	if (result < 0)
493 		return result;
494 
495 	if (priv->features & FEATURE_IRQ) {
496 		outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START,
497 		       SMBHSTCNT(priv));
498 		result = wait_event_timeout(priv->waitq,
499 					    (status = priv->status),
500 					    adap->timeout);
501 		if (!result) {
502 			status = -ETIMEDOUT;
503 			dev_warn(&priv->pci_dev->dev,
504 				 "Timeout waiting for interrupt!\n");
505 		}
506 		priv->status = 0;
507 		return i801_check_post(priv, status);
508 	}
509 
510 	/* the current contents of SMBHSTCNT can be overwritten, since PEC,
511 	 * SMBSCMD are passed in xact */
512 	outb_p(xact | SMBHSTCNT_START, SMBHSTCNT(priv));
513 
514 	status = i801_wait_intr(priv);
515 	return i801_check_post(priv, status);
516 }
517 
518 static int i801_block_transaction_by_block(struct i801_priv *priv,
519 					   union i2c_smbus_data *data,
520 					   char read_write, int command,
521 					   int hwpec)
522 {
523 	int i, len;
524 	int status;
525 	int xact = hwpec ? SMBHSTCNT_PEC_EN : 0;
526 
527 	switch (command) {
528 	case I2C_SMBUS_BLOCK_PROC_CALL:
529 		xact |= I801_BLOCK_PROC_CALL;
530 		break;
531 	case I2C_SMBUS_BLOCK_DATA:
532 		xact |= I801_BLOCK_DATA;
533 		break;
534 	default:
535 		return -EOPNOTSUPP;
536 	}
537 
538 	inb_p(SMBHSTCNT(priv)); /* reset the data buffer index */
539 
540 	/* Use 32-byte buffer to process this transaction */
541 	if (read_write == I2C_SMBUS_WRITE) {
542 		len = data->block[0];
543 		outb_p(len, SMBHSTDAT0(priv));
544 		for (i = 0; i < len; i++)
545 			outb_p(data->block[i+1], SMBBLKDAT(priv));
546 	}
547 
548 	status = i801_transaction(priv, xact);
549 	if (status)
550 		return status;
551 
552 	if (read_write == I2C_SMBUS_READ ||
553 	    command == I2C_SMBUS_BLOCK_PROC_CALL) {
554 		len = inb_p(SMBHSTDAT0(priv));
555 		if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)
556 			return -EPROTO;
557 
558 		data->block[0] = len;
559 		for (i = 0; i < len; i++)
560 			data->block[i + 1] = inb_p(SMBBLKDAT(priv));
561 	}
562 	return 0;
563 }
564 
565 static void i801_isr_byte_done(struct i801_priv *priv)
566 {
567 	if (priv->is_read) {
568 		/* For SMBus block reads, length is received with first byte */
569 		if (((priv->cmd & 0x1c) == I801_BLOCK_DATA) &&
570 		    (priv->count == 0)) {
571 			priv->len = inb_p(SMBHSTDAT0(priv));
572 			if (priv->len < 1 || priv->len > I2C_SMBUS_BLOCK_MAX) {
573 				dev_err(&priv->pci_dev->dev,
574 					"Illegal SMBus block read size %d\n",
575 					priv->len);
576 				/* FIXME: Recover */
577 				priv->len = I2C_SMBUS_BLOCK_MAX;
578 			} else {
579 				dev_dbg(&priv->pci_dev->dev,
580 					"SMBus block read size is %d\n",
581 					priv->len);
582 			}
583 			priv->data[-1] = priv->len;
584 		}
585 
586 		/* Read next byte */
587 		if (priv->count < priv->len)
588 			priv->data[priv->count++] = inb(SMBBLKDAT(priv));
589 		else
590 			dev_dbg(&priv->pci_dev->dev,
591 				"Discarding extra byte on block read\n");
592 
593 		/* Set LAST_BYTE for last byte of read transaction */
594 		if (priv->count == priv->len - 1)
595 			outb_p(priv->cmd | SMBHSTCNT_LAST_BYTE,
596 			       SMBHSTCNT(priv));
597 	} else if (priv->count < priv->len - 1) {
598 		/* Write next byte, except for IRQ after last byte */
599 		outb_p(priv->data[++priv->count], SMBBLKDAT(priv));
600 	}
601 
602 	/* Clear BYTE_DONE to continue with next byte */
603 	outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS(priv));
604 }
605 
606 static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)
607 {
608 	unsigned short addr;
609 
610 	addr = inb_p(SMBNTFDADD(priv)) >> 1;
611 
612 	/*
613 	 * With the tested platforms, reading SMBNTFDDAT (22 + (p)->smba)
614 	 * always returns 0. Our current implementation doesn't provide
615 	 * data, so we just ignore it.
616 	 */
617 	i2c_handle_smbus_host_notify(&priv->adapter, addr);
618 
619 	/* clear Host Notify bit and return */
620 	outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
621 	return IRQ_HANDLED;
622 }
623 
624 /*
625  * There are three kinds of interrupts:
626  *
627  * 1) i801 signals transaction completion with one of these interrupts:
628  *      INTR - Success
629  *      DEV_ERR - Invalid command, NAK or communication timeout
630  *      BUS_ERR - SMI# transaction collision
631  *      FAILED - transaction was canceled due to a KILL request
632  *    When any of these occur, update ->status and wake up the waitq.
633  *    ->status must be cleared before kicking off the next transaction.
634  *
635  * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt
636  *    occurs for each byte of a byte-by-byte to prepare the next byte.
637  *
638  * 3) Host Notify interrupts
639  */
640 static irqreturn_t i801_isr(int irq, void *dev_id)
641 {
642 	struct i801_priv *priv = dev_id;
643 	u16 pcists;
644 	u8 status;
645 
646 	/* Confirm this is our interrupt */
647 	pci_read_config_word(priv->pci_dev, SMBPCISTS, &pcists);
648 	if (!(pcists & SMBPCISTS_INTS))
649 		return IRQ_NONE;
650 
651 	if (priv->features & FEATURE_HOST_NOTIFY) {
652 		status = inb_p(SMBSLVSTS(priv));
653 		if (status & SMBSLVSTS_HST_NTFY_STS)
654 			return i801_host_notify_isr(priv);
655 	}
656 
657 	status = inb_p(SMBHSTSTS(priv));
658 	if (status & SMBHSTSTS_BYTE_DONE)
659 		i801_isr_byte_done(priv);
660 
661 	/*
662 	 * Clear irq sources and report transaction result.
663 	 * ->status must be cleared before the next transaction is started.
664 	 */
665 	status &= SMBHSTSTS_INTR | STATUS_ERROR_FLAGS;
666 	if (status) {
667 		outb_p(status, SMBHSTSTS(priv));
668 		priv->status = status;
669 		wake_up(&priv->waitq);
670 	}
671 
672 	return IRQ_HANDLED;
673 }
674 
675 /*
676  * For "byte-by-byte" block transactions:
677  *   I2C write uses cmd=I801_BLOCK_DATA, I2C_EN=1
678  *   I2C read uses cmd=I801_I2C_BLOCK_DATA
679  */
680 static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
681 					       union i2c_smbus_data *data,
682 					       char read_write, int command,
683 					       int hwpec)
684 {
685 	int i, len;
686 	int smbcmd;
687 	int status;
688 	int result;
689 	const struct i2c_adapter *adap = &priv->adapter;
690 
691 	if (command == I2C_SMBUS_BLOCK_PROC_CALL)
692 		return -EOPNOTSUPP;
693 
694 	result = i801_check_pre(priv);
695 	if (result < 0)
696 		return result;
697 
698 	len = data->block[0];
699 
700 	if (read_write == I2C_SMBUS_WRITE) {
701 		outb_p(len, SMBHSTDAT0(priv));
702 		outb_p(data->block[1], SMBBLKDAT(priv));
703 	}
704 
705 	if (command == I2C_SMBUS_I2C_BLOCK_DATA &&
706 	    read_write == I2C_SMBUS_READ)
707 		smbcmd = I801_I2C_BLOCK_DATA;
708 	else
709 		smbcmd = I801_BLOCK_DATA;
710 
711 	if (priv->features & FEATURE_IRQ) {
712 		priv->is_read = (read_write == I2C_SMBUS_READ);
713 		if (len == 1 && priv->is_read)
714 			smbcmd |= SMBHSTCNT_LAST_BYTE;
715 		priv->cmd = smbcmd | SMBHSTCNT_INTREN;
716 		priv->len = len;
717 		priv->count = 0;
718 		priv->data = &data->block[1];
719 
720 		outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv));
721 		result = wait_event_timeout(priv->waitq,
722 					    (status = priv->status),
723 					    adap->timeout);
724 		if (!result) {
725 			status = -ETIMEDOUT;
726 			dev_warn(&priv->pci_dev->dev,
727 				 "Timeout waiting for interrupt!\n");
728 		}
729 		priv->status = 0;
730 		return i801_check_post(priv, status);
731 	}
732 
733 	for (i = 1; i <= len; i++) {
734 		if (i == len && read_write == I2C_SMBUS_READ)
735 			smbcmd |= SMBHSTCNT_LAST_BYTE;
736 		outb_p(smbcmd, SMBHSTCNT(priv));
737 
738 		if (i == 1)
739 			outb_p(inb(SMBHSTCNT(priv)) | SMBHSTCNT_START,
740 			       SMBHSTCNT(priv));
741 
742 		status = i801_wait_byte_done(priv);
743 		if (status)
744 			goto exit;
745 
746 		if (i == 1 && read_write == I2C_SMBUS_READ
747 		 && command != I2C_SMBUS_I2C_BLOCK_DATA) {
748 			len = inb_p(SMBHSTDAT0(priv));
749 			if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {
750 				dev_err(&priv->pci_dev->dev,
751 					"Illegal SMBus block read size %d\n",
752 					len);
753 				/* Recover */
754 				while (inb_p(SMBHSTSTS(priv)) &
755 				       SMBHSTSTS_HOST_BUSY)
756 					outb_p(SMBHSTSTS_BYTE_DONE,
757 					       SMBHSTSTS(priv));
758 				outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv));
759 				return -EPROTO;
760 			}
761 			data->block[0] = len;
762 		}
763 
764 		/* Retrieve/store value in SMBBLKDAT */
765 		if (read_write == I2C_SMBUS_READ)
766 			data->block[i] = inb_p(SMBBLKDAT(priv));
767 		if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
768 			outb_p(data->block[i+1], SMBBLKDAT(priv));
769 
770 		/* signals SMBBLKDAT ready */
771 		outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS(priv));
772 	}
773 
774 	status = i801_wait_intr(priv);
775 exit:
776 	return i801_check_post(priv, status);
777 }
778 
779 static int i801_set_block_buffer_mode(struct i801_priv *priv)
780 {
781 	outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_E32B, SMBAUXCTL(priv));
782 	if ((inb_p(SMBAUXCTL(priv)) & SMBAUXCTL_E32B) == 0)
783 		return -EIO;
784 	return 0;
785 }
786 
787 /* Block transaction function */
788 static int i801_block_transaction(struct i801_priv *priv,
789 				  union i2c_smbus_data *data, char read_write,
790 				  int command, int hwpec)
791 {
792 	int result = 0;
793 	unsigned char hostc;
794 
795 	if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
796 		if (read_write == I2C_SMBUS_WRITE) {
797 			/* set I2C_EN bit in configuration register */
798 			pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &hostc);
799 			pci_write_config_byte(priv->pci_dev, SMBHSTCFG,
800 					      hostc | SMBHSTCFG_I2C_EN);
801 		} else if (!(priv->features & FEATURE_I2C_BLOCK_READ)) {
802 			dev_err(&priv->pci_dev->dev,
803 				"I2C block read is unsupported!\n");
804 			return -EOPNOTSUPP;
805 		}
806 	}
807 
808 	if (read_write == I2C_SMBUS_WRITE
809 	 || command == I2C_SMBUS_I2C_BLOCK_DATA) {
810 		if (data->block[0] < 1)
811 			data->block[0] = 1;
812 		if (data->block[0] > I2C_SMBUS_BLOCK_MAX)
813 			data->block[0] = I2C_SMBUS_BLOCK_MAX;
814 	} else {
815 		data->block[0] = 32;	/* max for SMBus block reads */
816 	}
817 
818 	/* Experience has shown that the block buffer can only be used for
819 	   SMBus (not I2C) block transactions, even though the datasheet
820 	   doesn't mention this limitation. */
821 	if ((priv->features & FEATURE_BLOCK_BUFFER)
822 	 && command != I2C_SMBUS_I2C_BLOCK_DATA
823 	 && i801_set_block_buffer_mode(priv) == 0)
824 		result = i801_block_transaction_by_block(priv, data,
825 							 read_write,
826 							 command, hwpec);
827 	else
828 		result = i801_block_transaction_byte_by_byte(priv, data,
829 							     read_write,
830 							     command, hwpec);
831 
832 	if (command == I2C_SMBUS_I2C_BLOCK_DATA
833 	 && read_write == I2C_SMBUS_WRITE) {
834 		/* restore saved configuration register value */
835 		pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hostc);
836 	}
837 	return result;
838 }
839 
840 /* Return negative errno on error. */
841 static s32 i801_access(struct i2c_adapter *adap, u16 addr,
842 		       unsigned short flags, char read_write, u8 command,
843 		       int size, union i2c_smbus_data *data)
844 {
845 	int hwpec;
846 	int block = 0;
847 	int ret = 0, xact = 0;
848 	struct i801_priv *priv = i2c_get_adapdata(adap);
849 
850 	mutex_lock(&priv->acpi_lock);
851 	if (priv->acpi_reserved) {
852 		mutex_unlock(&priv->acpi_lock);
853 		return -EBUSY;
854 	}
855 
856 	pm_runtime_get_sync(&priv->pci_dev->dev);
857 
858 	hwpec = (priv->features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
859 		&& size != I2C_SMBUS_QUICK
860 		&& size != I2C_SMBUS_I2C_BLOCK_DATA;
861 
862 	switch (size) {
863 	case I2C_SMBUS_QUICK:
864 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
865 		       SMBHSTADD(priv));
866 		xact = I801_QUICK;
867 		break;
868 	case I2C_SMBUS_BYTE:
869 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
870 		       SMBHSTADD(priv));
871 		if (read_write == I2C_SMBUS_WRITE)
872 			outb_p(command, SMBHSTCMD(priv));
873 		xact = I801_BYTE;
874 		break;
875 	case I2C_SMBUS_BYTE_DATA:
876 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
877 		       SMBHSTADD(priv));
878 		outb_p(command, SMBHSTCMD(priv));
879 		if (read_write == I2C_SMBUS_WRITE)
880 			outb_p(data->byte, SMBHSTDAT0(priv));
881 		xact = I801_BYTE_DATA;
882 		break;
883 	case I2C_SMBUS_WORD_DATA:
884 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
885 		       SMBHSTADD(priv));
886 		outb_p(command, SMBHSTCMD(priv));
887 		if (read_write == I2C_SMBUS_WRITE) {
888 			outb_p(data->word & 0xff, SMBHSTDAT0(priv));
889 			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1(priv));
890 		}
891 		xact = I801_WORD_DATA;
892 		break;
893 	case I2C_SMBUS_BLOCK_DATA:
894 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
895 		       SMBHSTADD(priv));
896 		outb_p(command, SMBHSTCMD(priv));
897 		block = 1;
898 		break;
899 	case I2C_SMBUS_I2C_BLOCK_DATA:
900 		/*
901 		 * NB: page 240 of ICH5 datasheet shows that the R/#W
902 		 * bit should be cleared here, even when reading.
903 		 * However if SPD Write Disable is set (Lynx Point and later),
904 		 * the read will fail if we don't set the R/#W bit.
905 		 */
906 		outb_p(((addr & 0x7f) << 1) |
907 		       ((priv->original_hstcfg & SMBHSTCFG_SPD_WD) ?
908 			(read_write & 0x01) : 0),
909 		       SMBHSTADD(priv));
910 		if (read_write == I2C_SMBUS_READ) {
911 			/* NB: page 240 of ICH5 datasheet also shows
912 			 * that DATA1 is the cmd field when reading */
913 			outb_p(command, SMBHSTDAT1(priv));
914 		} else
915 			outb_p(command, SMBHSTCMD(priv));
916 		block = 1;
917 		break;
918 	case I2C_SMBUS_BLOCK_PROC_CALL:
919 		/*
920 		 * Bit 0 of the slave address register always indicate a write
921 		 * command.
922 		 */
923 		outb_p((addr & 0x7f) << 1, SMBHSTADD(priv));
924 		outb_p(command, SMBHSTCMD(priv));
925 		block = 1;
926 		break;
927 	default:
928 		dev_err(&priv->pci_dev->dev, "Unsupported transaction %d\n",
929 			size);
930 		ret = -EOPNOTSUPP;
931 		goto out;
932 	}
933 
934 	if (hwpec)	/* enable/disable hardware PEC */
935 		outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_CRC, SMBAUXCTL(priv));
936 	else
937 		outb_p(inb_p(SMBAUXCTL(priv)) & (~SMBAUXCTL_CRC),
938 		       SMBAUXCTL(priv));
939 
940 	if (block)
941 		ret = i801_block_transaction(priv, data, read_write, size,
942 					     hwpec);
943 	else
944 		ret = i801_transaction(priv, xact);
945 
946 	/* Some BIOSes don't like it when PEC is enabled at reboot or resume
947 	   time, so we forcibly disable it after every transaction. Turn off
948 	   E32B for the same reason. */
949 	if (hwpec || block)
950 		outb_p(inb_p(SMBAUXCTL(priv)) &
951 		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));
952 
953 	if (block)
954 		goto out;
955 	if (ret)
956 		goto out;
957 	if ((read_write == I2C_SMBUS_WRITE) || (xact == I801_QUICK))
958 		goto out;
959 
960 	switch (xact & 0x7f) {
961 	case I801_BYTE:	/* Result put in SMBHSTDAT0 */
962 	case I801_BYTE_DATA:
963 		data->byte = inb_p(SMBHSTDAT0(priv));
964 		break;
965 	case I801_WORD_DATA:
966 		data->word = inb_p(SMBHSTDAT0(priv)) +
967 			     (inb_p(SMBHSTDAT1(priv)) << 8);
968 		break;
969 	}
970 
971 out:
972 	pm_runtime_mark_last_busy(&priv->pci_dev->dev);
973 	pm_runtime_put_autosuspend(&priv->pci_dev->dev);
974 	mutex_unlock(&priv->acpi_lock);
975 	return ret;
976 }
977 
978 
979 static u32 i801_func(struct i2c_adapter *adapter)
980 {
981 	struct i801_priv *priv = i2c_get_adapdata(adapter);
982 
983 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
984 	       I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
985 	       I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK |
986 	       ((priv->features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) |
987 	       ((priv->features & FEATURE_BLOCK_PROC) ?
988 		I2C_FUNC_SMBUS_BLOCK_PROC_CALL : 0) |
989 	       ((priv->features & FEATURE_I2C_BLOCK_READ) ?
990 		I2C_FUNC_SMBUS_READ_I2C_BLOCK : 0) |
991 	       ((priv->features & FEATURE_HOST_NOTIFY) ?
992 		I2C_FUNC_SMBUS_HOST_NOTIFY : 0);
993 }
994 
995 static void i801_enable_host_notify(struct i2c_adapter *adapter)
996 {
997 	struct i801_priv *priv = i2c_get_adapdata(adapter);
998 
999 	if (!(priv->features & FEATURE_HOST_NOTIFY))
1000 		return;
1001 
1002 	if (!(SMBSLVCMD_HST_NTFY_INTREN & priv->original_slvcmd))
1003 		outb_p(SMBSLVCMD_HST_NTFY_INTREN | priv->original_slvcmd,
1004 		       SMBSLVCMD(priv));
1005 
1006 	/* clear Host Notify bit to allow a new notification */
1007 	outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
1008 }
1009 
1010 static void i801_disable_host_notify(struct i801_priv *priv)
1011 {
1012 	if (!(priv->features & FEATURE_HOST_NOTIFY))
1013 		return;
1014 
1015 	outb_p(priv->original_slvcmd, SMBSLVCMD(priv));
1016 }
1017 
1018 static const struct i2c_algorithm smbus_algorithm = {
1019 	.smbus_xfer	= i801_access,
1020 	.functionality	= i801_func,
1021 };
1022 
1023 static const struct pci_device_id i801_ids[] = {
1024 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_3) },
1025 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_3) },
1026 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_2) },
1027 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_3) },
1028 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_3) },
1029 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_3) },
1030 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_4) },
1031 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_16) },
1032 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_17) },
1033 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB2_17) },
1034 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH8_5) },
1035 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH9_6) },
1036 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EP80579_1) },
1037 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_4) },
1038 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_5) },
1039 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS) },
1040 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS) },
1041 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS) },
1042 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0) },
1043 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1) },
1044 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2) },
1045 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS) },
1046 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PANTHERPOINT_SMBUS) },
1047 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS) },
1048 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_SMBUS) },
1049 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMBUS) },
1050 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS) },
1051 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS0) },
1052 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1) },
1053 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2) },
1054 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS) },
1055 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS) },
1056 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS) },
1057 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS) },
1058 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS) },
1059 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS) },
1060 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS) },
1061 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS) },
1062 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CDF_SMBUS) },
1063 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DNV_SMBUS) },
1064 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BROXTON_SMBUS) },
1065 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LEWISBURG_SMBUS) },
1066 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LEWISBURG_SSKU_SMBUS) },
1067 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_KABYLAKE_PCH_H_SMBUS) },
1068 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CANNONLAKE_H_SMBUS) },
1069 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CANNONLAKE_LP_SMBUS) },
1070 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICELAKE_LP_SMBUS) },
1071 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COMETLAKE_SMBUS) },
1072 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ELKHART_LAKE_SMBUS) },
1073 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TIGERLAKE_LP_SMBUS) },
1074 	{ 0, }
1075 };
1076 
1077 MODULE_DEVICE_TABLE(pci, i801_ids);
1078 
1079 #if defined CONFIG_X86 && defined CONFIG_DMI
1080 static unsigned char apanel_addr;
1081 
1082 /* Scan the system ROM for the signature "FJKEYINF" */
1083 static __init const void __iomem *bios_signature(const void __iomem *bios)
1084 {
1085 	ssize_t offset;
1086 	const unsigned char signature[] = "FJKEYINF";
1087 
1088 	for (offset = 0; offset < 0x10000; offset += 0x10) {
1089 		if (check_signature(bios + offset, signature,
1090 				    sizeof(signature)-1))
1091 			return bios + offset;
1092 	}
1093 	return NULL;
1094 }
1095 
1096 static void __init input_apanel_init(void)
1097 {
1098 	void __iomem *bios;
1099 	const void __iomem *p;
1100 
1101 	bios = ioremap(0xF0000, 0x10000); /* Can't fail */
1102 	p = bios_signature(bios);
1103 	if (p) {
1104 		/* just use the first address */
1105 		apanel_addr = readb(p + 8 + 3) >> 1;
1106 	}
1107 	iounmap(bios);
1108 }
1109 
1110 struct dmi_onboard_device_info {
1111 	const char *name;
1112 	u8 type;
1113 	unsigned short i2c_addr;
1114 	const char *i2c_type;
1115 };
1116 
1117 static const struct dmi_onboard_device_info dmi_devices[] = {
1118 	{ "Syleus", DMI_DEV_TYPE_OTHER, 0x73, "fscsyl" },
1119 	{ "Hermes", DMI_DEV_TYPE_OTHER, 0x73, "fscher" },
1120 	{ "Hades",  DMI_DEV_TYPE_OTHER, 0x73, "fschds" },
1121 };
1122 
1123 static void dmi_check_onboard_device(u8 type, const char *name,
1124 				     struct i2c_adapter *adap)
1125 {
1126 	int i;
1127 	struct i2c_board_info info;
1128 
1129 	for (i = 0; i < ARRAY_SIZE(dmi_devices); i++) {
1130 		/* & ~0x80, ignore enabled/disabled bit */
1131 		if ((type & ~0x80) != dmi_devices[i].type)
1132 			continue;
1133 		if (strcasecmp(name, dmi_devices[i].name))
1134 			continue;
1135 
1136 		memset(&info, 0, sizeof(struct i2c_board_info));
1137 		info.addr = dmi_devices[i].i2c_addr;
1138 		strlcpy(info.type, dmi_devices[i].i2c_type, I2C_NAME_SIZE);
1139 		i2c_new_device(adap, &info);
1140 		break;
1141 	}
1142 }
1143 
1144 /* We use our own function to check for onboard devices instead of
1145    dmi_find_device() as some buggy BIOS's have the devices we are interested
1146    in marked as disabled */
1147 static void dmi_check_onboard_devices(const struct dmi_header *dm, void *adap)
1148 {
1149 	int i, count;
1150 
1151 	if (dm->type != 10)
1152 		return;
1153 
1154 	count = (dm->length - sizeof(struct dmi_header)) / 2;
1155 	for (i = 0; i < count; i++) {
1156 		const u8 *d = (char *)(dm + 1) + (i * 2);
1157 		const char *name = ((char *) dm) + dm->length;
1158 		u8 type = d[0];
1159 		u8 s = d[1];
1160 
1161 		if (!s)
1162 			continue;
1163 		s--;
1164 		while (s > 0 && name[0]) {
1165 			name += strlen(name) + 1;
1166 			s--;
1167 		}
1168 		if (name[0] == 0) /* Bogus string reference */
1169 			continue;
1170 
1171 		dmi_check_onboard_device(type, name, adap);
1172 	}
1173 }
1174 
1175 /* NOTE: Keep this list in sync with drivers/platform/x86/dell-smo8800.c */
1176 static const char *const acpi_smo8800_ids[] = {
1177 	"SMO8800",
1178 	"SMO8801",
1179 	"SMO8810",
1180 	"SMO8811",
1181 	"SMO8820",
1182 	"SMO8821",
1183 	"SMO8830",
1184 	"SMO8831",
1185 };
1186 
1187 static acpi_status check_acpi_smo88xx_device(acpi_handle obj_handle,
1188 					     u32 nesting_level,
1189 					     void *context,
1190 					     void **return_value)
1191 {
1192 	struct acpi_device_info *info;
1193 	acpi_status status;
1194 	char *hid;
1195 	int i;
1196 
1197 	status = acpi_get_object_info(obj_handle, &info);
1198 	if (ACPI_FAILURE(status))
1199 		return AE_OK;
1200 
1201 	if (!(info->valid & ACPI_VALID_HID))
1202 		goto smo88xx_not_found;
1203 
1204 	hid = info->hardware_id.string;
1205 	if (!hid)
1206 		goto smo88xx_not_found;
1207 
1208 	i = match_string(acpi_smo8800_ids, ARRAY_SIZE(acpi_smo8800_ids), hid);
1209 	if (i < 0)
1210 		goto smo88xx_not_found;
1211 
1212 	kfree(info);
1213 
1214 	*((bool *)return_value) = true;
1215 	return AE_CTRL_TERMINATE;
1216 
1217 smo88xx_not_found:
1218 	kfree(info);
1219 	return AE_OK;
1220 }
1221 
1222 static bool is_dell_system_with_lis3lv02d(void)
1223 {
1224 	bool found;
1225 	const char *vendor;
1226 
1227 	vendor = dmi_get_system_info(DMI_SYS_VENDOR);
1228 	if (!vendor || strcmp(vendor, "Dell Inc."))
1229 		return false;
1230 
1231 	/*
1232 	 * Check that ACPI device SMO88xx is present and is functioning.
1233 	 * Function acpi_get_devices() already filters all ACPI devices
1234 	 * which are not present or are not functioning.
1235 	 * ACPI device SMO88xx represents our ST microelectronics lis3lv02d
1236 	 * accelerometer but unfortunately ACPI does not provide any other
1237 	 * information (like I2C address).
1238 	 */
1239 	found = false;
1240 	acpi_get_devices(NULL, check_acpi_smo88xx_device, NULL,
1241 			 (void **)&found);
1242 
1243 	return found;
1244 }
1245 
1246 /*
1247  * Accelerometer's I2C address is not specified in DMI nor ACPI,
1248  * so it is needed to define mapping table based on DMI product names.
1249  */
1250 static const struct {
1251 	const char *dmi_product_name;
1252 	unsigned short i2c_addr;
1253 } dell_lis3lv02d_devices[] = {
1254 	/*
1255 	 * Dell platform team told us that these Latitude devices have
1256 	 * ST microelectronics accelerometer at I2C address 0x29.
1257 	 */
1258 	{ "Latitude E5250",     0x29 },
1259 	{ "Latitude E5450",     0x29 },
1260 	{ "Latitude E5550",     0x29 },
1261 	{ "Latitude E6440",     0x29 },
1262 	{ "Latitude E6440 ATG", 0x29 },
1263 	{ "Latitude E6540",     0x29 },
1264 	/*
1265 	 * Additional individual entries were added after verification.
1266 	 */
1267 	{ "Vostro V131",        0x1d },
1268 };
1269 
1270 static void register_dell_lis3lv02d_i2c_device(struct i801_priv *priv)
1271 {
1272 	struct i2c_board_info info;
1273 	const char *dmi_product_name;
1274 	int i;
1275 
1276 	dmi_product_name = dmi_get_system_info(DMI_PRODUCT_NAME);
1277 	for (i = 0; i < ARRAY_SIZE(dell_lis3lv02d_devices); ++i) {
1278 		if (strcmp(dmi_product_name,
1279 			   dell_lis3lv02d_devices[i].dmi_product_name) == 0)
1280 			break;
1281 	}
1282 
1283 	if (i == ARRAY_SIZE(dell_lis3lv02d_devices)) {
1284 		dev_warn(&priv->pci_dev->dev,
1285 			 "Accelerometer lis3lv02d is present on SMBus but its"
1286 			 " address is unknown, skipping registration\n");
1287 		return;
1288 	}
1289 
1290 	memset(&info, 0, sizeof(struct i2c_board_info));
1291 	info.addr = dell_lis3lv02d_devices[i].i2c_addr;
1292 	strlcpy(info.type, "lis3lv02d", I2C_NAME_SIZE);
1293 	i2c_new_device(&priv->adapter, &info);
1294 }
1295 
1296 /* Register optional slaves */
1297 static void i801_probe_optional_slaves(struct i801_priv *priv)
1298 {
1299 	/* Only register slaves on main SMBus channel */
1300 	if (priv->features & FEATURE_IDF)
1301 		return;
1302 
1303 	if (apanel_addr) {
1304 		struct i2c_board_info info;
1305 
1306 		memset(&info, 0, sizeof(struct i2c_board_info));
1307 		info.addr = apanel_addr;
1308 		strlcpy(info.type, "fujitsu_apanel", I2C_NAME_SIZE);
1309 		i2c_new_device(&priv->adapter, &info);
1310 	}
1311 
1312 	if (dmi_name_in_vendors("FUJITSU"))
1313 		dmi_walk(dmi_check_onboard_devices, &priv->adapter);
1314 
1315 	if (is_dell_system_with_lis3lv02d())
1316 		register_dell_lis3lv02d_i2c_device(priv);
1317 }
1318 #else
1319 static void __init input_apanel_init(void) {}
1320 static void i801_probe_optional_slaves(struct i801_priv *priv) {}
1321 #endif	/* CONFIG_X86 && CONFIG_DMI */
1322 
1323 #if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
1324 static struct i801_mux_config i801_mux_config_asus_z8_d12 = {
1325 	.gpio_chip = "gpio_ich",
1326 	.values = { 0x02, 0x03 },
1327 	.n_values = 2,
1328 	.classes = { I2C_CLASS_SPD, I2C_CLASS_SPD },
1329 	.gpios = { 52, 53 },
1330 	.n_gpios = 2,
1331 };
1332 
1333 static struct i801_mux_config i801_mux_config_asus_z8_d18 = {
1334 	.gpio_chip = "gpio_ich",
1335 	.values = { 0x02, 0x03, 0x01 },
1336 	.n_values = 3,
1337 	.classes = { I2C_CLASS_SPD, I2C_CLASS_SPD, I2C_CLASS_SPD },
1338 	.gpios = { 52, 53 },
1339 	.n_gpios = 2,
1340 };
1341 
1342 static const struct dmi_system_id mux_dmi_table[] = {
1343 	{
1344 		.matches = {
1345 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1346 			DMI_MATCH(DMI_BOARD_NAME, "Z8NA-D6(C)"),
1347 		},
1348 		.driver_data = &i801_mux_config_asus_z8_d12,
1349 	},
1350 	{
1351 		.matches = {
1352 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1353 			DMI_MATCH(DMI_BOARD_NAME, "Z8P(N)E-D12(X)"),
1354 		},
1355 		.driver_data = &i801_mux_config_asus_z8_d12,
1356 	},
1357 	{
1358 		.matches = {
1359 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1360 			DMI_MATCH(DMI_BOARD_NAME, "Z8NH-D12"),
1361 		},
1362 		.driver_data = &i801_mux_config_asus_z8_d12,
1363 	},
1364 	{
1365 		.matches = {
1366 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1367 			DMI_MATCH(DMI_BOARD_NAME, "Z8PH-D12/IFB"),
1368 		},
1369 		.driver_data = &i801_mux_config_asus_z8_d12,
1370 	},
1371 	{
1372 		.matches = {
1373 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1374 			DMI_MATCH(DMI_BOARD_NAME, "Z8NR-D12"),
1375 		},
1376 		.driver_data = &i801_mux_config_asus_z8_d12,
1377 	},
1378 	{
1379 		.matches = {
1380 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1381 			DMI_MATCH(DMI_BOARD_NAME, "Z8P(N)H-D12"),
1382 		},
1383 		.driver_data = &i801_mux_config_asus_z8_d12,
1384 	},
1385 	{
1386 		.matches = {
1387 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1388 			DMI_MATCH(DMI_BOARD_NAME, "Z8PG-D18"),
1389 		},
1390 		.driver_data = &i801_mux_config_asus_z8_d18,
1391 	},
1392 	{
1393 		.matches = {
1394 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1395 			DMI_MATCH(DMI_BOARD_NAME, "Z8PE-D18"),
1396 		},
1397 		.driver_data = &i801_mux_config_asus_z8_d18,
1398 	},
1399 	{
1400 		.matches = {
1401 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1402 			DMI_MATCH(DMI_BOARD_NAME, "Z8PS-D12"),
1403 		},
1404 		.driver_data = &i801_mux_config_asus_z8_d12,
1405 	},
1406 	{ }
1407 };
1408 
1409 /* Setup multiplexing if needed */
1410 static int i801_add_mux(struct i801_priv *priv)
1411 {
1412 	struct device *dev = &priv->adapter.dev;
1413 	const struct i801_mux_config *mux_config;
1414 	struct i2c_mux_gpio_platform_data gpio_data;
1415 	struct gpiod_lookup_table *lookup;
1416 	int err, i;
1417 
1418 	if (!priv->mux_drvdata)
1419 		return 0;
1420 	mux_config = priv->mux_drvdata;
1421 
1422 	/* Prepare the platform data */
1423 	memset(&gpio_data, 0, sizeof(struct i2c_mux_gpio_platform_data));
1424 	gpio_data.parent = priv->adapter.nr;
1425 	gpio_data.values = mux_config->values;
1426 	gpio_data.n_values = mux_config->n_values;
1427 	gpio_data.classes = mux_config->classes;
1428 	gpio_data.idle = I2C_MUX_GPIO_NO_IDLE;
1429 
1430 	/* Register GPIO descriptor lookup table */
1431 	lookup = devm_kzalloc(dev,
1432 			      struct_size(lookup, table, mux_config->n_gpios),
1433 			      GFP_KERNEL);
1434 	if (!lookup)
1435 		return -ENOMEM;
1436 	lookup->dev_id = "i2c-mux-gpio";
1437 	for (i = 0; i < mux_config->n_gpios; i++) {
1438 		lookup->table[i].chip_label = mux_config->gpio_chip;
1439 		lookup->table[i].chip_hwnum = mux_config->gpios[i];
1440 		lookup->table[i].con_id = "mux";
1441 	}
1442 	gpiod_add_lookup_table(lookup);
1443 	priv->lookup = lookup;
1444 
1445 	/*
1446 	 * Register the mux device, we use PLATFORM_DEVID_NONE here
1447 	 * because since we are referring to the GPIO chip by name we are
1448 	 * anyways in deep trouble if there is more than one of these
1449 	 * devices, and there should likely only be one platform controller
1450 	 * hub.
1451 	 */
1452 	priv->mux_pdev = platform_device_register_data(dev, "i2c-mux-gpio",
1453 				PLATFORM_DEVID_NONE, &gpio_data,
1454 				sizeof(struct i2c_mux_gpio_platform_data));
1455 	if (IS_ERR(priv->mux_pdev)) {
1456 		err = PTR_ERR(priv->mux_pdev);
1457 		gpiod_remove_lookup_table(lookup);
1458 		priv->mux_pdev = NULL;
1459 		dev_err(dev, "Failed to register i2c-mux-gpio device\n");
1460 		return err;
1461 	}
1462 
1463 	return 0;
1464 }
1465 
1466 static void i801_del_mux(struct i801_priv *priv)
1467 {
1468 	if (priv->mux_pdev)
1469 		platform_device_unregister(priv->mux_pdev);
1470 	if (priv->lookup)
1471 		gpiod_remove_lookup_table(priv->lookup);
1472 }
1473 
1474 static unsigned int i801_get_adapter_class(struct i801_priv *priv)
1475 {
1476 	const struct dmi_system_id *id;
1477 	const struct i801_mux_config *mux_config;
1478 	unsigned int class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
1479 	int i;
1480 
1481 	id = dmi_first_match(mux_dmi_table);
1482 	if (id) {
1483 		/* Remove branch classes from trunk */
1484 		mux_config = id->driver_data;
1485 		for (i = 0; i < mux_config->n_values; i++)
1486 			class &= ~mux_config->classes[i];
1487 
1488 		/* Remember for later */
1489 		priv->mux_drvdata = mux_config;
1490 	}
1491 
1492 	return class;
1493 }
1494 #else
1495 static inline int i801_add_mux(struct i801_priv *priv) { return 0; }
1496 static inline void i801_del_mux(struct i801_priv *priv) { }
1497 
1498 static inline unsigned int i801_get_adapter_class(struct i801_priv *priv)
1499 {
1500 	return I2C_CLASS_HWMON | I2C_CLASS_SPD;
1501 }
1502 #endif
1503 
1504 static const struct itco_wdt_platform_data spt_tco_platform_data = {
1505 	.name = "Intel PCH",
1506 	.version = 4,
1507 };
1508 
1509 static DEFINE_SPINLOCK(p2sb_spinlock);
1510 
1511 static struct platform_device *
1512 i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev,
1513 		 struct resource *tco_res)
1514 {
1515 	struct resource *res;
1516 	unsigned int devfn;
1517 	u64 base64_addr;
1518 	u32 base_addr;
1519 	u8 hidden;
1520 
1521 	/*
1522 	 * We must access the NO_REBOOT bit over the Primary to Sideband
1523 	 * bridge (P2SB). The BIOS prevents the P2SB device from being
1524 	 * enumerated by the PCI subsystem, so we need to unhide/hide it
1525 	 * to lookup the P2SB BAR.
1526 	 */
1527 	spin_lock(&p2sb_spinlock);
1528 
1529 	devfn = PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 1);
1530 
1531 	/* Unhide the P2SB device, if it is hidden */
1532 	pci_bus_read_config_byte(pci_dev->bus, devfn, 0xe1, &hidden);
1533 	if (hidden)
1534 		pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, 0x0);
1535 
1536 	pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR, &base_addr);
1537 	base64_addr = base_addr & 0xfffffff0;
1538 
1539 	pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR + 0x4, &base_addr);
1540 	base64_addr |= (u64)base_addr << 32;
1541 
1542 	/* Hide the P2SB device, if it was hidden before */
1543 	if (hidden)
1544 		pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, hidden);
1545 	spin_unlock(&p2sb_spinlock);
1546 
1547 	res = &tco_res[ICH_RES_MEM_OFF];
1548 	if (pci_dev->device == PCI_DEVICE_ID_INTEL_DNV_SMBUS)
1549 		res->start = (resource_size_t)base64_addr + SBREG_SMBCTRL_DNV;
1550 	else
1551 		res->start = (resource_size_t)base64_addr + SBREG_SMBCTRL;
1552 
1553 	res->end = res->start + 3;
1554 	res->flags = IORESOURCE_MEM;
1555 
1556 	return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1,
1557 					tco_res, 3, &spt_tco_platform_data,
1558 					sizeof(spt_tco_platform_data));
1559 }
1560 
1561 static const struct itco_wdt_platform_data cnl_tco_platform_data = {
1562 	.name = "Intel PCH",
1563 	.version = 6,
1564 };
1565 
1566 static struct platform_device *
1567 i801_add_tco_cnl(struct i801_priv *priv, struct pci_dev *pci_dev,
1568 		 struct resource *tco_res)
1569 {
1570 	return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1,
1571 					tco_res, 2, &cnl_tco_platform_data,
1572 					sizeof(cnl_tco_platform_data));
1573 }
1574 
1575 static void i801_add_tco(struct i801_priv *priv)
1576 {
1577 	u32 base_addr, tco_base, tco_ctl, ctrl_val;
1578 	struct pci_dev *pci_dev = priv->pci_dev;
1579 	struct resource tco_res[3], *res;
1580 	unsigned int devfn;
1581 
1582 	/* If we have ACPI based watchdog use that instead */
1583 	if (acpi_has_watchdog())
1584 		return;
1585 
1586 	if (!(priv->features & (FEATURE_TCO_SPT | FEATURE_TCO_CNL)))
1587 		return;
1588 
1589 	pci_read_config_dword(pci_dev, TCOBASE, &tco_base);
1590 	pci_read_config_dword(pci_dev, TCOCTL, &tco_ctl);
1591 	if (!(tco_ctl & TCOCTL_EN))
1592 		return;
1593 
1594 	memset(tco_res, 0, sizeof(tco_res));
1595 
1596 	res = &tco_res[ICH_RES_IO_TCO];
1597 	res->start = tco_base & ~1;
1598 	res->end = res->start + 32 - 1;
1599 	res->flags = IORESOURCE_IO;
1600 
1601 	/*
1602 	 * Power Management registers.
1603 	 */
1604 	devfn = PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 2);
1605 	pci_bus_read_config_dword(pci_dev->bus, devfn, ACPIBASE, &base_addr);
1606 
1607 	res = &tco_res[ICH_RES_IO_SMI];
1608 	res->start = (base_addr & ~1) + ACPIBASE_SMI_OFF;
1609 	res->end = res->start + 3;
1610 	res->flags = IORESOURCE_IO;
1611 
1612 	/*
1613 	 * Enable the ACPI I/O space.
1614 	 */
1615 	pci_bus_read_config_dword(pci_dev->bus, devfn, ACPICTRL, &ctrl_val);
1616 	ctrl_val |= ACPICTRL_EN;
1617 	pci_bus_write_config_dword(pci_dev->bus, devfn, ACPICTRL, ctrl_val);
1618 
1619 	if (priv->features & FEATURE_TCO_CNL)
1620 		priv->tco_pdev = i801_add_tco_cnl(priv, pci_dev, tco_res);
1621 	else
1622 		priv->tco_pdev = i801_add_tco_spt(priv, pci_dev, tco_res);
1623 
1624 	if (IS_ERR(priv->tco_pdev))
1625 		dev_warn(&pci_dev->dev, "failed to create iTCO device\n");
1626 }
1627 
1628 #ifdef CONFIG_ACPI
1629 static bool i801_acpi_is_smbus_ioport(const struct i801_priv *priv,
1630 				      acpi_physical_address address)
1631 {
1632 	return address >= priv->smba &&
1633 	       address <= pci_resource_end(priv->pci_dev, SMBBAR);
1634 }
1635 
1636 static acpi_status
1637 i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits,
1638 		     u64 *value, void *handler_context, void *region_context)
1639 {
1640 	struct i801_priv *priv = handler_context;
1641 	struct pci_dev *pdev = priv->pci_dev;
1642 	acpi_status status;
1643 
1644 	/*
1645 	 * Once BIOS AML code touches the OpRegion we warn and inhibit any
1646 	 * further access from the driver itself. This device is now owned
1647 	 * by the system firmware.
1648 	 */
1649 	mutex_lock(&priv->acpi_lock);
1650 
1651 	if (!priv->acpi_reserved && i801_acpi_is_smbus_ioport(priv, address)) {
1652 		priv->acpi_reserved = true;
1653 
1654 		dev_warn(&pdev->dev, "BIOS is accessing SMBus registers\n");
1655 		dev_warn(&pdev->dev, "Driver SMBus register access inhibited\n");
1656 
1657 		/*
1658 		 * BIOS is accessing the host controller so prevent it from
1659 		 * suspending automatically from now on.
1660 		 */
1661 		pm_runtime_get_sync(&pdev->dev);
1662 	}
1663 
1664 	if ((function & ACPI_IO_MASK) == ACPI_READ)
1665 		status = acpi_os_read_port(address, (u32 *)value, bits);
1666 	else
1667 		status = acpi_os_write_port(address, (u32)*value, bits);
1668 
1669 	mutex_unlock(&priv->acpi_lock);
1670 
1671 	return status;
1672 }
1673 
1674 static int i801_acpi_probe(struct i801_priv *priv)
1675 {
1676 	struct acpi_device *adev;
1677 	acpi_status status;
1678 
1679 	adev = ACPI_COMPANION(&priv->pci_dev->dev);
1680 	if (adev) {
1681 		status = acpi_install_address_space_handler(adev->handle,
1682 				ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler,
1683 				NULL, priv);
1684 		if (ACPI_SUCCESS(status))
1685 			return 0;
1686 	}
1687 
1688 	return acpi_check_resource_conflict(&priv->pci_dev->resource[SMBBAR]);
1689 }
1690 
1691 static void i801_acpi_remove(struct i801_priv *priv)
1692 {
1693 	struct acpi_device *adev;
1694 
1695 	adev = ACPI_COMPANION(&priv->pci_dev->dev);
1696 	if (!adev)
1697 		return;
1698 
1699 	acpi_remove_address_space_handler(adev->handle,
1700 		ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler);
1701 
1702 	mutex_lock(&priv->acpi_lock);
1703 	if (priv->acpi_reserved)
1704 		pm_runtime_put(&priv->pci_dev->dev);
1705 	mutex_unlock(&priv->acpi_lock);
1706 }
1707 #else
1708 static inline int i801_acpi_probe(struct i801_priv *priv) { return 0; }
1709 static inline void i801_acpi_remove(struct i801_priv *priv) { }
1710 #endif
1711 
1712 static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
1713 {
1714 	unsigned char temp;
1715 	int err, i;
1716 	struct i801_priv *priv;
1717 
1718 	priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL);
1719 	if (!priv)
1720 		return -ENOMEM;
1721 
1722 	i2c_set_adapdata(&priv->adapter, priv);
1723 	priv->adapter.owner = THIS_MODULE;
1724 	priv->adapter.class = i801_get_adapter_class(priv);
1725 	priv->adapter.algo = &smbus_algorithm;
1726 	priv->adapter.dev.parent = &dev->dev;
1727 	ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&dev->dev));
1728 	priv->adapter.retries = 3;
1729 	mutex_init(&priv->acpi_lock);
1730 
1731 	priv->pci_dev = dev;
1732 	switch (dev->device) {
1733 	case PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS:
1734 	case PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS:
1735 	case PCI_DEVICE_ID_INTEL_LEWISBURG_SMBUS:
1736 	case PCI_DEVICE_ID_INTEL_LEWISBURG_SSKU_SMBUS:
1737 	case PCI_DEVICE_ID_INTEL_DNV_SMBUS:
1738 	case PCI_DEVICE_ID_INTEL_KABYLAKE_PCH_H_SMBUS:
1739 		priv->features |= FEATURE_BLOCK_PROC;
1740 		priv->features |= FEATURE_I2C_BLOCK_READ;
1741 		priv->features |= FEATURE_IRQ;
1742 		priv->features |= FEATURE_SMBUS_PEC;
1743 		priv->features |= FEATURE_BLOCK_BUFFER;
1744 		priv->features |= FEATURE_TCO_SPT;
1745 		priv->features |= FEATURE_HOST_NOTIFY;
1746 		break;
1747 
1748 	case PCI_DEVICE_ID_INTEL_CANNONLAKE_H_SMBUS:
1749 	case PCI_DEVICE_ID_INTEL_CANNONLAKE_LP_SMBUS:
1750 	case PCI_DEVICE_ID_INTEL_CDF_SMBUS:
1751 	case PCI_DEVICE_ID_INTEL_ICELAKE_LP_SMBUS:
1752 	case PCI_DEVICE_ID_INTEL_COMETLAKE_SMBUS:
1753 	case PCI_DEVICE_ID_INTEL_ELKHART_LAKE_SMBUS:
1754 	case PCI_DEVICE_ID_INTEL_TIGERLAKE_LP_SMBUS:
1755 		priv->features |= FEATURE_BLOCK_PROC;
1756 		priv->features |= FEATURE_I2C_BLOCK_READ;
1757 		priv->features |= FEATURE_IRQ;
1758 		priv->features |= FEATURE_SMBUS_PEC;
1759 		priv->features |= FEATURE_BLOCK_BUFFER;
1760 		priv->features |= FEATURE_TCO_CNL;
1761 		priv->features |= FEATURE_HOST_NOTIFY;
1762 		break;
1763 
1764 	case PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0:
1765 	case PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1:
1766 	case PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2:
1767 	case PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS0:
1768 	case PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1:
1769 	case PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2:
1770 		priv->features |= FEATURE_IDF;
1771 		/* fall through */
1772 	default:
1773 		priv->features |= FEATURE_BLOCK_PROC;
1774 		priv->features |= FEATURE_I2C_BLOCK_READ;
1775 		priv->features |= FEATURE_IRQ;
1776 		/* fall through */
1777 	case PCI_DEVICE_ID_INTEL_82801DB_3:
1778 		priv->features |= FEATURE_SMBUS_PEC;
1779 		priv->features |= FEATURE_BLOCK_BUFFER;
1780 		/* fall through */
1781 	case PCI_DEVICE_ID_INTEL_82801CA_3:
1782 		priv->features |= FEATURE_HOST_NOTIFY;
1783 		/* fall through */
1784 	case PCI_DEVICE_ID_INTEL_82801BA_2:
1785 	case PCI_DEVICE_ID_INTEL_82801AB_3:
1786 	case PCI_DEVICE_ID_INTEL_82801AA_3:
1787 		break;
1788 	}
1789 
1790 	/* Disable features on user request */
1791 	for (i = 0; i < ARRAY_SIZE(i801_feature_names); i++) {
1792 		if (priv->features & disable_features & (1 << i))
1793 			dev_notice(&dev->dev, "%s disabled by user\n",
1794 				   i801_feature_names[i]);
1795 	}
1796 	priv->features &= ~disable_features;
1797 
1798 	err = pcim_enable_device(dev);
1799 	if (err) {
1800 		dev_err(&dev->dev, "Failed to enable SMBus PCI device (%d)\n",
1801 			err);
1802 		return err;
1803 	}
1804 	pcim_pin_device(dev);
1805 
1806 	/* Determine the address of the SMBus area */
1807 	priv->smba = pci_resource_start(dev, SMBBAR);
1808 	if (!priv->smba) {
1809 		dev_err(&dev->dev,
1810 			"SMBus base address uninitialized, upgrade BIOS\n");
1811 		return -ENODEV;
1812 	}
1813 
1814 	if (i801_acpi_probe(priv))
1815 		return -ENODEV;
1816 
1817 	err = pcim_iomap_regions(dev, 1 << SMBBAR,
1818 				 dev_driver_string(&dev->dev));
1819 	if (err) {
1820 		dev_err(&dev->dev,
1821 			"Failed to request SMBus region 0x%lx-0x%Lx\n",
1822 			priv->smba,
1823 			(unsigned long long)pci_resource_end(dev, SMBBAR));
1824 		i801_acpi_remove(priv);
1825 		return err;
1826 	}
1827 
1828 	pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &temp);
1829 	priv->original_hstcfg = temp;
1830 	temp &= ~SMBHSTCFG_I2C_EN;	/* SMBus timing */
1831 	if (!(temp & SMBHSTCFG_HST_EN)) {
1832 		dev_info(&dev->dev, "Enabling SMBus device\n");
1833 		temp |= SMBHSTCFG_HST_EN;
1834 	}
1835 	pci_write_config_byte(priv->pci_dev, SMBHSTCFG, temp);
1836 
1837 	if (temp & SMBHSTCFG_SMB_SMI_EN) {
1838 		dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n");
1839 		/* Disable SMBus interrupt feature if SMBus using SMI# */
1840 		priv->features &= ~FEATURE_IRQ;
1841 	}
1842 	if (temp & SMBHSTCFG_SPD_WD)
1843 		dev_info(&dev->dev, "SPD Write Disable is set\n");
1844 
1845 	/* Clear special mode bits */
1846 	if (priv->features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))
1847 		outb_p(inb_p(SMBAUXCTL(priv)) &
1848 		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));
1849 
1850 	/* Remember original Host Notify setting */
1851 	if (priv->features & FEATURE_HOST_NOTIFY)
1852 		priv->original_slvcmd = inb_p(SMBSLVCMD(priv));
1853 
1854 	/* Default timeout in interrupt mode: 200 ms */
1855 	priv->adapter.timeout = HZ / 5;
1856 
1857 	if (dev->irq == IRQ_NOTCONNECTED)
1858 		priv->features &= ~FEATURE_IRQ;
1859 
1860 	if (priv->features & FEATURE_IRQ) {
1861 		u16 pcictl, pcists;
1862 
1863 		/* Complain if an interrupt is already pending */
1864 		pci_read_config_word(priv->pci_dev, SMBPCISTS, &pcists);
1865 		if (pcists & SMBPCISTS_INTS)
1866 			dev_warn(&dev->dev, "An interrupt is pending!\n");
1867 
1868 		/* Check if interrupts have been disabled */
1869 		pci_read_config_word(priv->pci_dev, SMBPCICTL, &pcictl);
1870 		if (pcictl & SMBPCICTL_INTDIS) {
1871 			dev_info(&dev->dev, "Interrupts are disabled\n");
1872 			priv->features &= ~FEATURE_IRQ;
1873 		}
1874 	}
1875 
1876 	if (priv->features & FEATURE_IRQ) {
1877 		init_waitqueue_head(&priv->waitq);
1878 
1879 		err = devm_request_irq(&dev->dev, dev->irq, i801_isr,
1880 				       IRQF_SHARED,
1881 				       dev_driver_string(&dev->dev), priv);
1882 		if (err) {
1883 			dev_err(&dev->dev, "Failed to allocate irq %d: %d\n",
1884 				dev->irq, err);
1885 			priv->features &= ~FEATURE_IRQ;
1886 		}
1887 	}
1888 	dev_info(&dev->dev, "SMBus using %s\n",
1889 		 priv->features & FEATURE_IRQ ? "PCI interrupt" : "polling");
1890 
1891 	i801_add_tco(priv);
1892 
1893 	snprintf(priv->adapter.name, sizeof(priv->adapter.name),
1894 		"SMBus I801 adapter at %04lx", priv->smba);
1895 	err = i2c_add_adapter(&priv->adapter);
1896 	if (err) {
1897 		i801_acpi_remove(priv);
1898 		return err;
1899 	}
1900 
1901 	i801_enable_host_notify(&priv->adapter);
1902 
1903 	i801_probe_optional_slaves(priv);
1904 	/* We ignore errors - multiplexing is optional */
1905 	i801_add_mux(priv);
1906 
1907 	pci_set_drvdata(dev, priv);
1908 
1909 	pm_runtime_set_autosuspend_delay(&dev->dev, 1000);
1910 	pm_runtime_use_autosuspend(&dev->dev);
1911 	pm_runtime_put_autosuspend(&dev->dev);
1912 	pm_runtime_allow(&dev->dev);
1913 
1914 	return 0;
1915 }
1916 
1917 static void i801_remove(struct pci_dev *dev)
1918 {
1919 	struct i801_priv *priv = pci_get_drvdata(dev);
1920 
1921 	pm_runtime_forbid(&dev->dev);
1922 	pm_runtime_get_noresume(&dev->dev);
1923 
1924 	i801_disable_host_notify(priv);
1925 	i801_del_mux(priv);
1926 	i2c_del_adapter(&priv->adapter);
1927 	i801_acpi_remove(priv);
1928 	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
1929 
1930 	platform_device_unregister(priv->tco_pdev);
1931 
1932 	/*
1933 	 * do not call pci_disable_device(dev) since it can cause hard hangs on
1934 	 * some systems during power-off (eg. Fujitsu-Siemens Lifebook E8010)
1935 	 */
1936 }
1937 
1938 static void i801_shutdown(struct pci_dev *dev)
1939 {
1940 	struct i801_priv *priv = pci_get_drvdata(dev);
1941 
1942 	/* Restore config registers to avoid hard hang on some systems */
1943 	i801_disable_host_notify(priv);
1944 	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
1945 }
1946 
1947 #ifdef CONFIG_PM_SLEEP
1948 static int i801_suspend(struct device *dev)
1949 {
1950 	struct pci_dev *pci_dev = to_pci_dev(dev);
1951 	struct i801_priv *priv = pci_get_drvdata(pci_dev);
1952 
1953 	pci_write_config_byte(pci_dev, SMBHSTCFG, priv->original_hstcfg);
1954 	return 0;
1955 }
1956 
1957 static int i801_resume(struct device *dev)
1958 {
1959 	struct i801_priv *priv = dev_get_drvdata(dev);
1960 
1961 	i801_enable_host_notify(&priv->adapter);
1962 
1963 	return 0;
1964 }
1965 #endif
1966 
1967 static SIMPLE_DEV_PM_OPS(i801_pm_ops, i801_suspend, i801_resume);
1968 
1969 static struct pci_driver i801_driver = {
1970 	.name		= "i801_smbus",
1971 	.id_table	= i801_ids,
1972 	.probe		= i801_probe,
1973 	.remove		= i801_remove,
1974 	.shutdown	= i801_shutdown,
1975 	.driver		= {
1976 		.pm	= &i801_pm_ops,
1977 	},
1978 };
1979 
1980 static int __init i2c_i801_init(void)
1981 {
1982 	if (dmi_name_in_vendors("FUJITSU"))
1983 		input_apanel_init();
1984 	return pci_register_driver(&i801_driver);
1985 }
1986 
1987 static void __exit i2c_i801_exit(void)
1988 {
1989 	pci_unregister_driver(&i801_driver);
1990 }
1991 
1992 MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>, Jean Delvare <jdelvare@suse.de>");
1993 MODULE_DESCRIPTION("I801 SMBus driver");
1994 MODULE_LICENSE("GPL");
1995 
1996 module_init(i2c_i801_init);
1997 module_exit(i2c_i801_exit);
1998