xref: /openbmc/linux/drivers/i2c/busses/i2c-i801.c (revision 11a163f2)
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  * Emmitsburg (PCH)		0x1bc9	32	hard	yes	yes	yes
58  * Broxton (SOC)		0x5ad4	32	hard	yes	yes	yes
59  * Lewisburg (PCH)		0xa1a3	32	hard	yes	yes	yes
60  * Lewisburg Supersku (PCH)	0xa223	32	hard	yes	yes	yes
61  * Kaby Lake PCH-H (PCH)	0xa2a3	32	hard	yes	yes	yes
62  * Gemini Lake (SOC)		0x31d4	32	hard	yes	yes	yes
63  * Cannon Lake-H (PCH)		0xa323	32	hard	yes	yes	yes
64  * Cannon Lake-LP (PCH)		0x9da3	32	hard	yes	yes	yes
65  * Cedar Fork (PCH)		0x18df	32	hard	yes	yes	yes
66  * Ice Lake-LP (PCH)		0x34a3	32	hard	yes	yes	yes
67  * Comet Lake (PCH)		0x02a3	32	hard	yes	yes	yes
68  * Comet Lake-H (PCH)		0x06a3	32	hard	yes	yes	yes
69  * Elkhart Lake (PCH)		0x4b23	32	hard	yes	yes	yes
70  * Tiger Lake-LP (PCH)		0xa0a3	32	hard	yes	yes	yes
71  * Tiger Lake-H (PCH)		0x43a3	32	hard	yes	yes	yes
72  * Jasper Lake (SOC)		0x4da3	32	hard	yes	yes	yes
73  * Comet Lake-V (PCH)		0xa3a3	32	hard	yes	yes	yes
74  * Alder Lake-S (PCH)		0x7aa3	32	hard	yes	yes	yes
75  *
76  * Features supported by this driver:
77  * Software PEC				no
78  * Hardware PEC				yes
79  * Block buffer				yes
80  * Block process call transaction	yes
81  * I2C block read transaction		yes (doesn't use the block buffer)
82  * Slave mode				no
83  * SMBus Host Notify			yes
84  * Interrupt processing			yes
85  *
86  * See the file Documentation/i2c/busses/i2c-i801.rst for details.
87  */
88 
89 #include <linux/interrupt.h>
90 #include <linux/module.h>
91 #include <linux/pci.h>
92 #include <linux/kernel.h>
93 #include <linux/stddef.h>
94 #include <linux/delay.h>
95 #include <linux/ioport.h>
96 #include <linux/init.h>
97 #include <linux/i2c.h>
98 #include <linux/i2c-smbus.h>
99 #include <linux/acpi.h>
100 #include <linux/io.h>
101 #include <linux/dmi.h>
102 #include <linux/slab.h>
103 #include <linux/string.h>
104 #include <linux/wait.h>
105 #include <linux/err.h>
106 #include <linux/platform_device.h>
107 #include <linux/platform_data/itco_wdt.h>
108 #include <linux/pm_runtime.h>
109 
110 #if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
111 #include <linux/gpio/machine.h>
112 #include <linux/platform_data/i2c-mux-gpio.h>
113 #endif
114 
115 /* I801 SMBus address offsets */
116 #define SMBHSTSTS(p)	(0 + (p)->smba)
117 #define SMBHSTCNT(p)	(2 + (p)->smba)
118 #define SMBHSTCMD(p)	(3 + (p)->smba)
119 #define SMBHSTADD(p)	(4 + (p)->smba)
120 #define SMBHSTDAT0(p)	(5 + (p)->smba)
121 #define SMBHSTDAT1(p)	(6 + (p)->smba)
122 #define SMBBLKDAT(p)	(7 + (p)->smba)
123 #define SMBPEC(p)	(8 + (p)->smba)		/* ICH3 and later */
124 #define SMBAUXSTS(p)	(12 + (p)->smba)	/* ICH4 and later */
125 #define SMBAUXCTL(p)	(13 + (p)->smba)	/* ICH4 and later */
126 #define SMBSLVSTS(p)	(16 + (p)->smba)	/* ICH3 and later */
127 #define SMBSLVCMD(p)	(17 + (p)->smba)	/* ICH3 and later */
128 #define SMBNTFDADD(p)	(20 + (p)->smba)	/* ICH3 and later */
129 
130 /* PCI Address Constants */
131 #define SMBBAR		4
132 #define SMBPCICTL	0x004
133 #define SMBPCISTS	0x006
134 #define SMBHSTCFG	0x040
135 #define TCOBASE		0x050
136 #define TCOCTL		0x054
137 
138 #define SBREG_BAR		0x10
139 #define SBREG_SMBCTRL		0xc6000c
140 #define SBREG_SMBCTRL_DNV	0xcf000c
141 
142 /* Host status bits for SMBPCISTS */
143 #define SMBPCISTS_INTS		BIT(3)
144 
145 /* Control bits for SMBPCICTL */
146 #define SMBPCICTL_INTDIS	BIT(10)
147 
148 /* Host configuration bits for SMBHSTCFG */
149 #define SMBHSTCFG_HST_EN	BIT(0)
150 #define SMBHSTCFG_SMB_SMI_EN	BIT(1)
151 #define SMBHSTCFG_I2C_EN	BIT(2)
152 #define SMBHSTCFG_SPD_WD	BIT(4)
153 
154 /* TCO configuration bits for TCOCTL */
155 #define TCOCTL_EN		BIT(8)
156 
157 /* Auxiliary status register bits, ICH4+ only */
158 #define SMBAUXSTS_CRCE		BIT(0)
159 #define SMBAUXSTS_STCO		BIT(1)
160 
161 /* Auxiliary control register bits, ICH4+ only */
162 #define SMBAUXCTL_CRC		BIT(0)
163 #define SMBAUXCTL_E32B		BIT(1)
164 
165 /* Other settings */
166 #define MAX_RETRIES		400
167 
168 /* I801 command constants */
169 #define I801_QUICK		0x00
170 #define I801_BYTE		0x04
171 #define I801_BYTE_DATA		0x08
172 #define I801_WORD_DATA		0x0C
173 #define I801_PROC_CALL		0x10	/* unimplemented */
174 #define I801_BLOCK_DATA		0x14
175 #define I801_I2C_BLOCK_DATA	0x18	/* ICH5 and later */
176 #define I801_BLOCK_PROC_CALL	0x1C
177 
178 /* I801 Host Control register bits */
179 #define SMBHSTCNT_INTREN	BIT(0)
180 #define SMBHSTCNT_KILL		BIT(1)
181 #define SMBHSTCNT_LAST_BYTE	BIT(5)
182 #define SMBHSTCNT_START		BIT(6)
183 #define SMBHSTCNT_PEC_EN	BIT(7)	/* ICH3 and later */
184 
185 /* I801 Hosts Status register bits */
186 #define SMBHSTSTS_BYTE_DONE	BIT(7)
187 #define SMBHSTSTS_INUSE_STS	BIT(6)
188 #define SMBHSTSTS_SMBALERT_STS	BIT(5)
189 #define SMBHSTSTS_FAILED	BIT(4)
190 #define SMBHSTSTS_BUS_ERR	BIT(3)
191 #define SMBHSTSTS_DEV_ERR	BIT(2)
192 #define SMBHSTSTS_INTR		BIT(1)
193 #define SMBHSTSTS_HOST_BUSY	BIT(0)
194 
195 /* Host Notify Status register bits */
196 #define SMBSLVSTS_HST_NTFY_STS	BIT(0)
197 
198 /* Host Notify Command register bits */
199 #define SMBSLVCMD_HST_NTFY_INTREN	BIT(0)
200 
201 #define STATUS_ERROR_FLAGS	(SMBHSTSTS_FAILED | SMBHSTSTS_BUS_ERR | \
202 				 SMBHSTSTS_DEV_ERR)
203 
204 #define STATUS_FLAGS		(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR | \
205 				 STATUS_ERROR_FLAGS)
206 
207 /* Older devices have their ID defined in <linux/pci_ids.h> */
208 #define PCI_DEVICE_ID_INTEL_COMETLAKE_SMBUS		0x02a3
209 #define PCI_DEVICE_ID_INTEL_COMETLAKE_H_SMBUS		0x06a3
210 #define PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS		0x0f12
211 #define PCI_DEVICE_ID_INTEL_CDF_SMBUS			0x18df
212 #define PCI_DEVICE_ID_INTEL_DNV_SMBUS			0x19df
213 #define PCI_DEVICE_ID_INTEL_EBG_SMBUS			0x1bc9
214 #define PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS		0x1c22
215 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS		0x1d22
216 /* Patsburg also has three 'Integrated Device Function' SMBus controllers */
217 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0		0x1d70
218 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1		0x1d71
219 #define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2		0x1d72
220 #define PCI_DEVICE_ID_INTEL_PANTHERPOINT_SMBUS		0x1e22
221 #define PCI_DEVICE_ID_INTEL_AVOTON_SMBUS		0x1f3c
222 #define PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS		0x2292
223 #define PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS		0x2330
224 #define PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS		0x23b0
225 #define PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS		0x31d4
226 #define PCI_DEVICE_ID_INTEL_ICELAKE_LP_SMBUS		0x34a3
227 #define PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS		0x3b30
228 #define PCI_DEVICE_ID_INTEL_TIGERLAKE_H_SMBUS		0x43a3
229 #define PCI_DEVICE_ID_INTEL_ELKHART_LAKE_SMBUS		0x4b23
230 #define PCI_DEVICE_ID_INTEL_JASPER_LAKE_SMBUS		0x4da3
231 #define PCI_DEVICE_ID_INTEL_BROXTON_SMBUS		0x5ad4
232 #define PCI_DEVICE_ID_INTEL_ALDER_LAKE_S_SMBUS		0x7aa3
233 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS		0x8c22
234 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS		0x8ca2
235 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS		0x8d22
236 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS0		0x8d7d
237 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1		0x8d7e
238 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2		0x8d7f
239 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_SMBUS		0x9c22
240 #define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS	0x9ca2
241 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS	0x9d23
242 #define PCI_DEVICE_ID_INTEL_CANNONLAKE_LP_SMBUS		0x9da3
243 #define PCI_DEVICE_ID_INTEL_TIGERLAKE_LP_SMBUS		0xa0a3
244 #define PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS	0xa123
245 #define PCI_DEVICE_ID_INTEL_LEWISBURG_SMBUS		0xa1a3
246 #define PCI_DEVICE_ID_INTEL_LEWISBURG_SSKU_SMBUS	0xa223
247 #define PCI_DEVICE_ID_INTEL_KABYLAKE_PCH_H_SMBUS	0xa2a3
248 #define PCI_DEVICE_ID_INTEL_CANNONLAKE_H_SMBUS		0xa323
249 #define PCI_DEVICE_ID_INTEL_COMETLAKE_V_SMBUS		0xa3a3
250 
251 struct i801_mux_config {
252 	char *gpio_chip;
253 	unsigned values[3];
254 	int n_values;
255 	unsigned classes[3];
256 	unsigned gpios[2];		/* Relative to gpio_chip->base */
257 	int n_gpios;
258 };
259 
260 struct i801_priv {
261 	struct i2c_adapter adapter;
262 	unsigned long smba;
263 	unsigned char original_hstcfg;
264 	unsigned char original_slvcmd;
265 	struct pci_dev *pci_dev;
266 	unsigned int features;
267 
268 	/* isr processing */
269 	wait_queue_head_t waitq;
270 	u8 status;
271 
272 	/* Command state used by isr for byte-by-byte block transactions */
273 	u8 cmd;
274 	bool is_read;
275 	int count;
276 	int len;
277 	u8 *data;
278 
279 #if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
280 	const struct i801_mux_config *mux_drvdata;
281 	struct platform_device *mux_pdev;
282 	struct gpiod_lookup_table *lookup;
283 #endif
284 	struct platform_device *tco_pdev;
285 
286 	/*
287 	 * If set to true the host controller registers are reserved for
288 	 * ACPI AML use. Protected by acpi_lock.
289 	 */
290 	bool acpi_reserved;
291 	struct mutex acpi_lock;
292 };
293 
294 #define FEATURE_SMBUS_PEC	BIT(0)
295 #define FEATURE_BLOCK_BUFFER	BIT(1)
296 #define FEATURE_BLOCK_PROC	BIT(2)
297 #define FEATURE_I2C_BLOCK_READ	BIT(3)
298 #define FEATURE_IRQ		BIT(4)
299 #define FEATURE_HOST_NOTIFY	BIT(5)
300 /* Not really a feature, but it's convenient to handle it as such */
301 #define FEATURE_IDF		BIT(15)
302 #define FEATURE_TCO_SPT		BIT(16)
303 #define FEATURE_TCO_CNL		BIT(17)
304 
305 static const char *i801_feature_names[] = {
306 	"SMBus PEC",
307 	"Block buffer",
308 	"Block process call",
309 	"I2C block read",
310 	"Interrupt",
311 	"SMBus Host Notify",
312 };
313 
314 static unsigned int disable_features;
315 module_param(disable_features, uint, S_IRUGO | S_IWUSR);
316 MODULE_PARM_DESC(disable_features, "Disable selected driver features:\n"
317 	"\t\t  0x01  disable SMBus PEC\n"
318 	"\t\t  0x02  disable the block buffer\n"
319 	"\t\t  0x08  disable the I2C block read functionality\n"
320 	"\t\t  0x10  don't use interrupts\n"
321 	"\t\t  0x20  disable SMBus Host Notify ");
322 
323 /* Make sure the SMBus host is ready to start transmitting.
324    Return 0 if it is, -EBUSY if it is not. */
325 static int i801_check_pre(struct i801_priv *priv)
326 {
327 	int status;
328 
329 	status = inb_p(SMBHSTSTS(priv));
330 	if (status & SMBHSTSTS_HOST_BUSY) {
331 		dev_err(&priv->pci_dev->dev, "SMBus is busy, can't use it!\n");
332 		return -EBUSY;
333 	}
334 
335 	status &= STATUS_FLAGS;
336 	if (status) {
337 		dev_dbg(&priv->pci_dev->dev, "Clearing status flags (%02x)\n",
338 			status);
339 		outb_p(status, SMBHSTSTS(priv));
340 		status = inb_p(SMBHSTSTS(priv)) & STATUS_FLAGS;
341 		if (status) {
342 			dev_err(&priv->pci_dev->dev,
343 				"Failed clearing status flags (%02x)\n",
344 				status);
345 			return -EBUSY;
346 		}
347 	}
348 
349 	/*
350 	 * Clear CRC status if needed.
351 	 * During normal operation, i801_check_post() takes care
352 	 * of it after every operation.  We do it here only in case
353 	 * the hardware was already in this state when the driver
354 	 * started.
355 	 */
356 	if (priv->features & FEATURE_SMBUS_PEC) {
357 		status = inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE;
358 		if (status) {
359 			dev_dbg(&priv->pci_dev->dev,
360 				"Clearing aux status flags (%02x)\n", status);
361 			outb_p(status, SMBAUXSTS(priv));
362 			status = inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE;
363 			if (status) {
364 				dev_err(&priv->pci_dev->dev,
365 					"Failed clearing aux status flags (%02x)\n",
366 					status);
367 				return -EBUSY;
368 			}
369 		}
370 	}
371 
372 	return 0;
373 }
374 
375 /*
376  * Convert the status register to an error code, and clear it.
377  * Note that status only contains the bits we want to clear, not the
378  * actual register value.
379  */
380 static int i801_check_post(struct i801_priv *priv, int status)
381 {
382 	int result = 0;
383 
384 	/*
385 	 * If the SMBus is still busy, we give up
386 	 * Note: This timeout condition only happens when using polling
387 	 * transactions.  For interrupt operation, NAK/timeout is indicated by
388 	 * DEV_ERR.
389 	 */
390 	if (unlikely(status < 0)) {
391 		dev_err(&priv->pci_dev->dev, "Transaction timeout\n");
392 		/* try to stop the current command */
393 		dev_dbg(&priv->pci_dev->dev, "Terminating the current operation\n");
394 		outb_p(inb_p(SMBHSTCNT(priv)) | SMBHSTCNT_KILL,
395 		       SMBHSTCNT(priv));
396 		usleep_range(1000, 2000);
397 		outb_p(inb_p(SMBHSTCNT(priv)) & (~SMBHSTCNT_KILL),
398 		       SMBHSTCNT(priv));
399 
400 		/* Check if it worked */
401 		status = inb_p(SMBHSTSTS(priv));
402 		if ((status & SMBHSTSTS_HOST_BUSY) ||
403 		    !(status & SMBHSTSTS_FAILED))
404 			dev_err(&priv->pci_dev->dev,
405 				"Failed terminating the transaction\n");
406 		outb_p(STATUS_FLAGS, SMBHSTSTS(priv));
407 		return -ETIMEDOUT;
408 	}
409 
410 	if (status & SMBHSTSTS_FAILED) {
411 		result = -EIO;
412 		dev_err(&priv->pci_dev->dev, "Transaction failed\n");
413 	}
414 	if (status & SMBHSTSTS_DEV_ERR) {
415 		/*
416 		 * This may be a PEC error, check and clear it.
417 		 *
418 		 * AUXSTS is handled differently from HSTSTS.
419 		 * For HSTSTS, i801_isr() or i801_wait_intr()
420 		 * has already cleared the error bits in hardware,
421 		 * and we are passed a copy of the original value
422 		 * in "status".
423 		 * For AUXSTS, the hardware register is left
424 		 * for us to handle here.
425 		 * This is asymmetric, slightly iffy, but safe,
426 		 * since all this code is serialized and the CRCE
427 		 * bit is harmless as long as it's cleared before
428 		 * the next operation.
429 		 */
430 		if ((priv->features & FEATURE_SMBUS_PEC) &&
431 		    (inb_p(SMBAUXSTS(priv)) & SMBAUXSTS_CRCE)) {
432 			outb_p(SMBAUXSTS_CRCE, SMBAUXSTS(priv));
433 			result = -EBADMSG;
434 			dev_dbg(&priv->pci_dev->dev, "PEC error\n");
435 		} else {
436 			result = -ENXIO;
437 			dev_dbg(&priv->pci_dev->dev, "No response\n");
438 		}
439 	}
440 	if (status & SMBHSTSTS_BUS_ERR) {
441 		result = -EAGAIN;
442 		dev_dbg(&priv->pci_dev->dev, "Lost arbitration\n");
443 	}
444 
445 	/* Clear status flags except BYTE_DONE, to be cleared by caller */
446 	outb_p(status, SMBHSTSTS(priv));
447 
448 	return result;
449 }
450 
451 /* Wait for BUSY being cleared and either INTR or an error flag being set */
452 static int i801_wait_intr(struct i801_priv *priv)
453 {
454 	int timeout = 0;
455 	int status;
456 
457 	/* We will always wait for a fraction of a second! */
458 	do {
459 		usleep_range(250, 500);
460 		status = inb_p(SMBHSTSTS(priv));
461 	} while (((status & SMBHSTSTS_HOST_BUSY) ||
462 		  !(status & (STATUS_ERROR_FLAGS | SMBHSTSTS_INTR))) &&
463 		 (timeout++ < MAX_RETRIES));
464 
465 	if (timeout > MAX_RETRIES) {
466 		dev_dbg(&priv->pci_dev->dev, "INTR Timeout!\n");
467 		return -ETIMEDOUT;
468 	}
469 	return status & (STATUS_ERROR_FLAGS | SMBHSTSTS_INTR);
470 }
471 
472 /* Wait for either BYTE_DONE or an error flag being set */
473 static int i801_wait_byte_done(struct i801_priv *priv)
474 {
475 	int timeout = 0;
476 	int status;
477 
478 	/* We will always wait for a fraction of a second! */
479 	do {
480 		usleep_range(250, 500);
481 		status = inb_p(SMBHSTSTS(priv));
482 	} while (!(status & (STATUS_ERROR_FLAGS | SMBHSTSTS_BYTE_DONE)) &&
483 		 (timeout++ < MAX_RETRIES));
484 
485 	if (timeout > MAX_RETRIES) {
486 		dev_dbg(&priv->pci_dev->dev, "BYTE_DONE Timeout!\n");
487 		return -ETIMEDOUT;
488 	}
489 	return status & STATUS_ERROR_FLAGS;
490 }
491 
492 static int i801_transaction(struct i801_priv *priv, int xact)
493 {
494 	int status;
495 	int result;
496 	const struct i2c_adapter *adap = &priv->adapter;
497 
498 	result = i801_check_pre(priv);
499 	if (result < 0)
500 		return result;
501 
502 	if (priv->features & FEATURE_IRQ) {
503 		outb_p(xact | SMBHSTCNT_INTREN | SMBHSTCNT_START,
504 		       SMBHSTCNT(priv));
505 		result = wait_event_timeout(priv->waitq,
506 					    (status = priv->status),
507 					    adap->timeout);
508 		if (!result) {
509 			status = -ETIMEDOUT;
510 			dev_warn(&priv->pci_dev->dev,
511 				 "Timeout waiting for interrupt!\n");
512 		}
513 		priv->status = 0;
514 		return i801_check_post(priv, status);
515 	}
516 
517 	/* the current contents of SMBHSTCNT can be overwritten, since PEC,
518 	 * SMBSCMD are passed in xact */
519 	outb_p(xact | SMBHSTCNT_START, SMBHSTCNT(priv));
520 
521 	status = i801_wait_intr(priv);
522 	return i801_check_post(priv, status);
523 }
524 
525 static int i801_block_transaction_by_block(struct i801_priv *priv,
526 					   union i2c_smbus_data *data,
527 					   char read_write, int command,
528 					   int hwpec)
529 {
530 	int i, len;
531 	int status;
532 	int xact = hwpec ? SMBHSTCNT_PEC_EN : 0;
533 
534 	switch (command) {
535 	case I2C_SMBUS_BLOCK_PROC_CALL:
536 		xact |= I801_BLOCK_PROC_CALL;
537 		break;
538 	case I2C_SMBUS_BLOCK_DATA:
539 		xact |= I801_BLOCK_DATA;
540 		break;
541 	default:
542 		return -EOPNOTSUPP;
543 	}
544 
545 	inb_p(SMBHSTCNT(priv)); /* reset the data buffer index */
546 
547 	/* Use 32-byte buffer to process this transaction */
548 	if (read_write == I2C_SMBUS_WRITE) {
549 		len = data->block[0];
550 		outb_p(len, SMBHSTDAT0(priv));
551 		for (i = 0; i < len; i++)
552 			outb_p(data->block[i+1], SMBBLKDAT(priv));
553 	}
554 
555 	status = i801_transaction(priv, xact);
556 	if (status)
557 		return status;
558 
559 	if (read_write == I2C_SMBUS_READ ||
560 	    command == I2C_SMBUS_BLOCK_PROC_CALL) {
561 		len = inb_p(SMBHSTDAT0(priv));
562 		if (len < 1 || len > I2C_SMBUS_BLOCK_MAX)
563 			return -EPROTO;
564 
565 		data->block[0] = len;
566 		for (i = 0; i < len; i++)
567 			data->block[i + 1] = inb_p(SMBBLKDAT(priv));
568 	}
569 	return 0;
570 }
571 
572 static void i801_isr_byte_done(struct i801_priv *priv)
573 {
574 	if (priv->is_read) {
575 		/* For SMBus block reads, length is received with first byte */
576 		if (((priv->cmd & 0x1c) == I801_BLOCK_DATA) &&
577 		    (priv->count == 0)) {
578 			priv->len = inb_p(SMBHSTDAT0(priv));
579 			if (priv->len < 1 || priv->len > I2C_SMBUS_BLOCK_MAX) {
580 				dev_err(&priv->pci_dev->dev,
581 					"Illegal SMBus block read size %d\n",
582 					priv->len);
583 				/* FIXME: Recover */
584 				priv->len = I2C_SMBUS_BLOCK_MAX;
585 			} else {
586 				dev_dbg(&priv->pci_dev->dev,
587 					"SMBus block read size is %d\n",
588 					priv->len);
589 			}
590 			priv->data[-1] = priv->len;
591 		}
592 
593 		/* Read next byte */
594 		if (priv->count < priv->len)
595 			priv->data[priv->count++] = inb(SMBBLKDAT(priv));
596 		else
597 			dev_dbg(&priv->pci_dev->dev,
598 				"Discarding extra byte on block read\n");
599 
600 		/* Set LAST_BYTE for last byte of read transaction */
601 		if (priv->count == priv->len - 1)
602 			outb_p(priv->cmd | SMBHSTCNT_LAST_BYTE,
603 			       SMBHSTCNT(priv));
604 	} else if (priv->count < priv->len - 1) {
605 		/* Write next byte, except for IRQ after last byte */
606 		outb_p(priv->data[++priv->count], SMBBLKDAT(priv));
607 	}
608 
609 	/* Clear BYTE_DONE to continue with next byte */
610 	outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS(priv));
611 }
612 
613 static irqreturn_t i801_host_notify_isr(struct i801_priv *priv)
614 {
615 	unsigned short addr;
616 
617 	addr = inb_p(SMBNTFDADD(priv)) >> 1;
618 
619 	/*
620 	 * With the tested platforms, reading SMBNTFDDAT (22 + (p)->smba)
621 	 * always returns 0. Our current implementation doesn't provide
622 	 * data, so we just ignore it.
623 	 */
624 	i2c_handle_smbus_host_notify(&priv->adapter, addr);
625 
626 	/* clear Host Notify bit and return */
627 	outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
628 	return IRQ_HANDLED;
629 }
630 
631 /*
632  * There are three kinds of interrupts:
633  *
634  * 1) i801 signals transaction completion with one of these interrupts:
635  *      INTR - Success
636  *      DEV_ERR - Invalid command, NAK or communication timeout
637  *      BUS_ERR - SMI# transaction collision
638  *      FAILED - transaction was canceled due to a KILL request
639  *    When any of these occur, update ->status and wake up the waitq.
640  *    ->status must be cleared before kicking off the next transaction.
641  *
642  * 2) For byte-by-byte (I2C read/write) transactions, one BYTE_DONE interrupt
643  *    occurs for each byte of a byte-by-byte to prepare the next byte.
644  *
645  * 3) Host Notify interrupts
646  */
647 static irqreturn_t i801_isr(int irq, void *dev_id)
648 {
649 	struct i801_priv *priv = dev_id;
650 	u16 pcists;
651 	u8 status;
652 
653 	/* Confirm this is our interrupt */
654 	pci_read_config_word(priv->pci_dev, SMBPCISTS, &pcists);
655 	if (!(pcists & SMBPCISTS_INTS))
656 		return IRQ_NONE;
657 
658 	if (priv->features & FEATURE_HOST_NOTIFY) {
659 		status = inb_p(SMBSLVSTS(priv));
660 		if (status & SMBSLVSTS_HST_NTFY_STS)
661 			return i801_host_notify_isr(priv);
662 	}
663 
664 	status = inb_p(SMBHSTSTS(priv));
665 	if (status & SMBHSTSTS_BYTE_DONE)
666 		i801_isr_byte_done(priv);
667 
668 	/*
669 	 * Clear irq sources and report transaction result.
670 	 * ->status must be cleared before the next transaction is started.
671 	 */
672 	status &= SMBHSTSTS_INTR | STATUS_ERROR_FLAGS;
673 	if (status) {
674 		outb_p(status, SMBHSTSTS(priv));
675 		priv->status = status;
676 		wake_up(&priv->waitq);
677 	}
678 
679 	return IRQ_HANDLED;
680 }
681 
682 /*
683  * For "byte-by-byte" block transactions:
684  *   I2C write uses cmd=I801_BLOCK_DATA, I2C_EN=1
685  *   I2C read uses cmd=I801_I2C_BLOCK_DATA
686  */
687 static int i801_block_transaction_byte_by_byte(struct i801_priv *priv,
688 					       union i2c_smbus_data *data,
689 					       char read_write, int command,
690 					       int hwpec)
691 {
692 	int i, len;
693 	int smbcmd;
694 	int status;
695 	int result;
696 	const struct i2c_adapter *adap = &priv->adapter;
697 
698 	if (command == I2C_SMBUS_BLOCK_PROC_CALL)
699 		return -EOPNOTSUPP;
700 
701 	result = i801_check_pre(priv);
702 	if (result < 0)
703 		return result;
704 
705 	len = data->block[0];
706 
707 	if (read_write == I2C_SMBUS_WRITE) {
708 		outb_p(len, SMBHSTDAT0(priv));
709 		outb_p(data->block[1], SMBBLKDAT(priv));
710 	}
711 
712 	if (command == I2C_SMBUS_I2C_BLOCK_DATA &&
713 	    read_write == I2C_SMBUS_READ)
714 		smbcmd = I801_I2C_BLOCK_DATA;
715 	else
716 		smbcmd = I801_BLOCK_DATA;
717 
718 	if (priv->features & FEATURE_IRQ) {
719 		priv->is_read = (read_write == I2C_SMBUS_READ);
720 		if (len == 1 && priv->is_read)
721 			smbcmd |= SMBHSTCNT_LAST_BYTE;
722 		priv->cmd = smbcmd | SMBHSTCNT_INTREN;
723 		priv->len = len;
724 		priv->count = 0;
725 		priv->data = &data->block[1];
726 
727 		outb_p(priv->cmd | SMBHSTCNT_START, SMBHSTCNT(priv));
728 		result = wait_event_timeout(priv->waitq,
729 					    (status = priv->status),
730 					    adap->timeout);
731 		if (!result) {
732 			status = -ETIMEDOUT;
733 			dev_warn(&priv->pci_dev->dev,
734 				 "Timeout waiting for interrupt!\n");
735 		}
736 		priv->status = 0;
737 		return i801_check_post(priv, status);
738 	}
739 
740 	for (i = 1; i <= len; i++) {
741 		if (i == len && read_write == I2C_SMBUS_READ)
742 			smbcmd |= SMBHSTCNT_LAST_BYTE;
743 		outb_p(smbcmd, SMBHSTCNT(priv));
744 
745 		if (i == 1)
746 			outb_p(inb(SMBHSTCNT(priv)) | SMBHSTCNT_START,
747 			       SMBHSTCNT(priv));
748 
749 		status = i801_wait_byte_done(priv);
750 		if (status)
751 			goto exit;
752 
753 		if (i == 1 && read_write == I2C_SMBUS_READ
754 		 && command != I2C_SMBUS_I2C_BLOCK_DATA) {
755 			len = inb_p(SMBHSTDAT0(priv));
756 			if (len < 1 || len > I2C_SMBUS_BLOCK_MAX) {
757 				dev_err(&priv->pci_dev->dev,
758 					"Illegal SMBus block read size %d\n",
759 					len);
760 				/* Recover */
761 				while (inb_p(SMBHSTSTS(priv)) &
762 				       SMBHSTSTS_HOST_BUSY)
763 					outb_p(SMBHSTSTS_BYTE_DONE,
764 					       SMBHSTSTS(priv));
765 				outb_p(SMBHSTSTS_INTR, SMBHSTSTS(priv));
766 				return -EPROTO;
767 			}
768 			data->block[0] = len;
769 		}
770 
771 		/* Retrieve/store value in SMBBLKDAT */
772 		if (read_write == I2C_SMBUS_READ)
773 			data->block[i] = inb_p(SMBBLKDAT(priv));
774 		if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
775 			outb_p(data->block[i+1], SMBBLKDAT(priv));
776 
777 		/* signals SMBBLKDAT ready */
778 		outb_p(SMBHSTSTS_BYTE_DONE, SMBHSTSTS(priv));
779 	}
780 
781 	status = i801_wait_intr(priv);
782 exit:
783 	return i801_check_post(priv, status);
784 }
785 
786 static int i801_set_block_buffer_mode(struct i801_priv *priv)
787 {
788 	outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_E32B, SMBAUXCTL(priv));
789 	if ((inb_p(SMBAUXCTL(priv)) & SMBAUXCTL_E32B) == 0)
790 		return -EIO;
791 	return 0;
792 }
793 
794 /* Block transaction function */
795 static int i801_block_transaction(struct i801_priv *priv,
796 				  union i2c_smbus_data *data, char read_write,
797 				  int command, int hwpec)
798 {
799 	int result = 0;
800 	unsigned char hostc;
801 
802 	if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
803 		if (read_write == I2C_SMBUS_WRITE) {
804 			/* set I2C_EN bit in configuration register */
805 			pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &hostc);
806 			pci_write_config_byte(priv->pci_dev, SMBHSTCFG,
807 					      hostc | SMBHSTCFG_I2C_EN);
808 		} else if (!(priv->features & FEATURE_I2C_BLOCK_READ)) {
809 			dev_err(&priv->pci_dev->dev,
810 				"I2C block read is unsupported!\n");
811 			return -EOPNOTSUPP;
812 		}
813 	}
814 
815 	if (read_write == I2C_SMBUS_WRITE
816 	 || command == I2C_SMBUS_I2C_BLOCK_DATA) {
817 		if (data->block[0] < 1)
818 			data->block[0] = 1;
819 		if (data->block[0] > I2C_SMBUS_BLOCK_MAX)
820 			data->block[0] = I2C_SMBUS_BLOCK_MAX;
821 	} else {
822 		data->block[0] = 32;	/* max for SMBus block reads */
823 	}
824 
825 	/* Experience has shown that the block buffer can only be used for
826 	   SMBus (not I2C) block transactions, even though the datasheet
827 	   doesn't mention this limitation. */
828 	if ((priv->features & FEATURE_BLOCK_BUFFER)
829 	 && command != I2C_SMBUS_I2C_BLOCK_DATA
830 	 && i801_set_block_buffer_mode(priv) == 0)
831 		result = i801_block_transaction_by_block(priv, data,
832 							 read_write,
833 							 command, hwpec);
834 	else
835 		result = i801_block_transaction_byte_by_byte(priv, data,
836 							     read_write,
837 							     command, hwpec);
838 
839 	if (command == I2C_SMBUS_I2C_BLOCK_DATA
840 	 && read_write == I2C_SMBUS_WRITE) {
841 		/* restore saved configuration register value */
842 		pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hostc);
843 	}
844 	return result;
845 }
846 
847 /* Return negative errno on error. */
848 static s32 i801_access(struct i2c_adapter *adap, u16 addr,
849 		       unsigned short flags, char read_write, u8 command,
850 		       int size, union i2c_smbus_data *data)
851 {
852 	int hwpec;
853 	int block = 0;
854 	int ret = 0, xact = 0;
855 	struct i801_priv *priv = i2c_get_adapdata(adap);
856 
857 	mutex_lock(&priv->acpi_lock);
858 	if (priv->acpi_reserved) {
859 		mutex_unlock(&priv->acpi_lock);
860 		return -EBUSY;
861 	}
862 
863 	pm_runtime_get_sync(&priv->pci_dev->dev);
864 
865 	hwpec = (priv->features & FEATURE_SMBUS_PEC) && (flags & I2C_CLIENT_PEC)
866 		&& size != I2C_SMBUS_QUICK
867 		&& size != I2C_SMBUS_I2C_BLOCK_DATA;
868 
869 	switch (size) {
870 	case I2C_SMBUS_QUICK:
871 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
872 		       SMBHSTADD(priv));
873 		xact = I801_QUICK;
874 		break;
875 	case I2C_SMBUS_BYTE:
876 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
877 		       SMBHSTADD(priv));
878 		if (read_write == I2C_SMBUS_WRITE)
879 			outb_p(command, SMBHSTCMD(priv));
880 		xact = I801_BYTE;
881 		break;
882 	case I2C_SMBUS_BYTE_DATA:
883 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
884 		       SMBHSTADD(priv));
885 		outb_p(command, SMBHSTCMD(priv));
886 		if (read_write == I2C_SMBUS_WRITE)
887 			outb_p(data->byte, SMBHSTDAT0(priv));
888 		xact = I801_BYTE_DATA;
889 		break;
890 	case I2C_SMBUS_WORD_DATA:
891 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
892 		       SMBHSTADD(priv));
893 		outb_p(command, SMBHSTCMD(priv));
894 		if (read_write == I2C_SMBUS_WRITE) {
895 			outb_p(data->word & 0xff, SMBHSTDAT0(priv));
896 			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1(priv));
897 		}
898 		xact = I801_WORD_DATA;
899 		break;
900 	case I2C_SMBUS_BLOCK_DATA:
901 		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
902 		       SMBHSTADD(priv));
903 		outb_p(command, SMBHSTCMD(priv));
904 		block = 1;
905 		break;
906 	case I2C_SMBUS_I2C_BLOCK_DATA:
907 		/*
908 		 * NB: page 240 of ICH5 datasheet shows that the R/#W
909 		 * bit should be cleared here, even when reading.
910 		 * However if SPD Write Disable is set (Lynx Point and later),
911 		 * the read will fail if we don't set the R/#W bit.
912 		 */
913 		outb_p(((addr & 0x7f) << 1) |
914 		       ((priv->original_hstcfg & SMBHSTCFG_SPD_WD) ?
915 			(read_write & 0x01) : 0),
916 		       SMBHSTADD(priv));
917 		if (read_write == I2C_SMBUS_READ) {
918 			/* NB: page 240 of ICH5 datasheet also shows
919 			 * that DATA1 is the cmd field when reading */
920 			outb_p(command, SMBHSTDAT1(priv));
921 		} else
922 			outb_p(command, SMBHSTCMD(priv));
923 		block = 1;
924 		break;
925 	case I2C_SMBUS_BLOCK_PROC_CALL:
926 		/*
927 		 * Bit 0 of the slave address register always indicate a write
928 		 * command.
929 		 */
930 		outb_p((addr & 0x7f) << 1, SMBHSTADD(priv));
931 		outb_p(command, SMBHSTCMD(priv));
932 		block = 1;
933 		break;
934 	default:
935 		dev_err(&priv->pci_dev->dev, "Unsupported transaction %d\n",
936 			size);
937 		ret = -EOPNOTSUPP;
938 		goto out;
939 	}
940 
941 	if (hwpec)	/* enable/disable hardware PEC */
942 		outb_p(inb_p(SMBAUXCTL(priv)) | SMBAUXCTL_CRC, SMBAUXCTL(priv));
943 	else
944 		outb_p(inb_p(SMBAUXCTL(priv)) & (~SMBAUXCTL_CRC),
945 		       SMBAUXCTL(priv));
946 
947 	if (block)
948 		ret = i801_block_transaction(priv, data, read_write, size,
949 					     hwpec);
950 	else
951 		ret = i801_transaction(priv, xact);
952 
953 	/* Some BIOSes don't like it when PEC is enabled at reboot or resume
954 	   time, so we forcibly disable it after every transaction. Turn off
955 	   E32B for the same reason. */
956 	if (hwpec || block)
957 		outb_p(inb_p(SMBAUXCTL(priv)) &
958 		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));
959 
960 	if (block)
961 		goto out;
962 	if (ret)
963 		goto out;
964 	if ((read_write == I2C_SMBUS_WRITE) || (xact == I801_QUICK))
965 		goto out;
966 
967 	switch (xact & 0x7f) {
968 	case I801_BYTE:	/* Result put in SMBHSTDAT0 */
969 	case I801_BYTE_DATA:
970 		data->byte = inb_p(SMBHSTDAT0(priv));
971 		break;
972 	case I801_WORD_DATA:
973 		data->word = inb_p(SMBHSTDAT0(priv)) +
974 			     (inb_p(SMBHSTDAT1(priv)) << 8);
975 		break;
976 	}
977 
978 out:
979 	pm_runtime_mark_last_busy(&priv->pci_dev->dev);
980 	pm_runtime_put_autosuspend(&priv->pci_dev->dev);
981 	mutex_unlock(&priv->acpi_lock);
982 	return ret;
983 }
984 
985 
986 static u32 i801_func(struct i2c_adapter *adapter)
987 {
988 	struct i801_priv *priv = i2c_get_adapdata(adapter);
989 
990 	return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
991 	       I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
992 	       I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK |
993 	       ((priv->features & FEATURE_SMBUS_PEC) ? I2C_FUNC_SMBUS_PEC : 0) |
994 	       ((priv->features & FEATURE_BLOCK_PROC) ?
995 		I2C_FUNC_SMBUS_BLOCK_PROC_CALL : 0) |
996 	       ((priv->features & FEATURE_I2C_BLOCK_READ) ?
997 		I2C_FUNC_SMBUS_READ_I2C_BLOCK : 0) |
998 	       ((priv->features & FEATURE_HOST_NOTIFY) ?
999 		I2C_FUNC_SMBUS_HOST_NOTIFY : 0);
1000 }
1001 
1002 static void i801_enable_host_notify(struct i2c_adapter *adapter)
1003 {
1004 	struct i801_priv *priv = i2c_get_adapdata(adapter);
1005 
1006 	if (!(priv->features & FEATURE_HOST_NOTIFY))
1007 		return;
1008 
1009 	if (!(SMBSLVCMD_HST_NTFY_INTREN & priv->original_slvcmd))
1010 		outb_p(SMBSLVCMD_HST_NTFY_INTREN | priv->original_slvcmd,
1011 		       SMBSLVCMD(priv));
1012 
1013 	/* clear Host Notify bit to allow a new notification */
1014 	outb_p(SMBSLVSTS_HST_NTFY_STS, SMBSLVSTS(priv));
1015 }
1016 
1017 static void i801_disable_host_notify(struct i801_priv *priv)
1018 {
1019 	if (!(priv->features & FEATURE_HOST_NOTIFY))
1020 		return;
1021 
1022 	outb_p(priv->original_slvcmd, SMBSLVCMD(priv));
1023 }
1024 
1025 static const struct i2c_algorithm smbus_algorithm = {
1026 	.smbus_xfer	= i801_access,
1027 	.functionality	= i801_func,
1028 };
1029 
1030 static const struct pci_device_id i801_ids[] = {
1031 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_3) },
1032 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_3) },
1033 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_2) },
1034 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_3) },
1035 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_3) },
1036 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_3) },
1037 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_4) },
1038 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_16) },
1039 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_17) },
1040 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB2_17) },
1041 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH8_5) },
1042 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH9_6) },
1043 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EP80579_1) },
1044 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_4) },
1045 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_5) },
1046 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS) },
1047 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS) },
1048 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS) },
1049 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0) },
1050 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1) },
1051 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2) },
1052 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS) },
1053 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PANTHERPOINT_SMBUS) },
1054 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS) },
1055 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_SMBUS) },
1056 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_AVOTON_SMBUS) },
1057 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS) },
1058 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS0) },
1059 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1) },
1060 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2) },
1061 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS) },
1062 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_GEMINILAKE_SMBUS) },
1063 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_SMBUS) },
1064 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS) },
1065 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BAYTRAIL_SMBUS) },
1066 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BRASWELL_SMBUS) },
1067 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS) },
1068 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS) },
1069 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CDF_SMBUS) },
1070 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_DNV_SMBUS) },
1071 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_EBG_SMBUS) },
1072 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_BROXTON_SMBUS) },
1073 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LEWISBURG_SMBUS) },
1074 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_LEWISBURG_SSKU_SMBUS) },
1075 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_KABYLAKE_PCH_H_SMBUS) },
1076 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CANNONLAKE_H_SMBUS) },
1077 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CANNONLAKE_LP_SMBUS) },
1078 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICELAKE_LP_SMBUS) },
1079 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COMETLAKE_SMBUS) },
1080 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COMETLAKE_H_SMBUS) },
1081 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COMETLAKE_V_SMBUS) },
1082 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ELKHART_LAKE_SMBUS) },
1083 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TIGERLAKE_LP_SMBUS) },
1084 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_TIGERLAKE_H_SMBUS) },
1085 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_JASPER_LAKE_SMBUS) },
1086 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ALDER_LAKE_S_SMBUS) },
1087 	{ 0, }
1088 };
1089 
1090 MODULE_DEVICE_TABLE(pci, i801_ids);
1091 
1092 #if defined CONFIG_X86 && defined CONFIG_DMI
1093 static unsigned char apanel_addr;
1094 
1095 /* Scan the system ROM for the signature "FJKEYINF" */
1096 static __init const void __iomem *bios_signature(const void __iomem *bios)
1097 {
1098 	ssize_t offset;
1099 	const unsigned char signature[] = "FJKEYINF";
1100 
1101 	for (offset = 0; offset < 0x10000; offset += 0x10) {
1102 		if (check_signature(bios + offset, signature,
1103 				    sizeof(signature)-1))
1104 			return bios + offset;
1105 	}
1106 	return NULL;
1107 }
1108 
1109 static void __init input_apanel_init(void)
1110 {
1111 	void __iomem *bios;
1112 	const void __iomem *p;
1113 
1114 	bios = ioremap(0xF0000, 0x10000); /* Can't fail */
1115 	p = bios_signature(bios);
1116 	if (p) {
1117 		/* just use the first address */
1118 		apanel_addr = readb(p + 8 + 3) >> 1;
1119 	}
1120 	iounmap(bios);
1121 }
1122 
1123 struct dmi_onboard_device_info {
1124 	const char *name;
1125 	u8 type;
1126 	unsigned short i2c_addr;
1127 	const char *i2c_type;
1128 };
1129 
1130 static const struct dmi_onboard_device_info dmi_devices[] = {
1131 	{ "Syleus", DMI_DEV_TYPE_OTHER, 0x73, "fscsyl" },
1132 	{ "Hermes", DMI_DEV_TYPE_OTHER, 0x73, "fscher" },
1133 	{ "Hades",  DMI_DEV_TYPE_OTHER, 0x73, "fschds" },
1134 };
1135 
1136 static void dmi_check_onboard_device(u8 type, const char *name,
1137 				     struct i2c_adapter *adap)
1138 {
1139 	int i;
1140 	struct i2c_board_info info;
1141 
1142 	for (i = 0; i < ARRAY_SIZE(dmi_devices); i++) {
1143 		/* & ~0x80, ignore enabled/disabled bit */
1144 		if ((type & ~0x80) != dmi_devices[i].type)
1145 			continue;
1146 		if (strcasecmp(name, dmi_devices[i].name))
1147 			continue;
1148 
1149 		memset(&info, 0, sizeof(struct i2c_board_info));
1150 		info.addr = dmi_devices[i].i2c_addr;
1151 		strlcpy(info.type, dmi_devices[i].i2c_type, I2C_NAME_SIZE);
1152 		i2c_new_client_device(adap, &info);
1153 		break;
1154 	}
1155 }
1156 
1157 /* We use our own function to check for onboard devices instead of
1158    dmi_find_device() as some buggy BIOS's have the devices we are interested
1159    in marked as disabled */
1160 static void dmi_check_onboard_devices(const struct dmi_header *dm, void *adap)
1161 {
1162 	int i, count;
1163 
1164 	if (dm->type != 10)
1165 		return;
1166 
1167 	count = (dm->length - sizeof(struct dmi_header)) / 2;
1168 	for (i = 0; i < count; i++) {
1169 		const u8 *d = (char *)(dm + 1) + (i * 2);
1170 		const char *name = ((char *) dm) + dm->length;
1171 		u8 type = d[0];
1172 		u8 s = d[1];
1173 
1174 		if (!s)
1175 			continue;
1176 		s--;
1177 		while (s > 0 && name[0]) {
1178 			name += strlen(name) + 1;
1179 			s--;
1180 		}
1181 		if (name[0] == 0) /* Bogus string reference */
1182 			continue;
1183 
1184 		dmi_check_onboard_device(type, name, adap);
1185 	}
1186 }
1187 
1188 /* NOTE: Keep this list in sync with drivers/platform/x86/dell-smo8800.c */
1189 static const char *const acpi_smo8800_ids[] = {
1190 	"SMO8800",
1191 	"SMO8801",
1192 	"SMO8810",
1193 	"SMO8811",
1194 	"SMO8820",
1195 	"SMO8821",
1196 	"SMO8830",
1197 	"SMO8831",
1198 };
1199 
1200 static acpi_status check_acpi_smo88xx_device(acpi_handle obj_handle,
1201 					     u32 nesting_level,
1202 					     void *context,
1203 					     void **return_value)
1204 {
1205 	struct acpi_device_info *info;
1206 	acpi_status status;
1207 	char *hid;
1208 	int i;
1209 
1210 	status = acpi_get_object_info(obj_handle, &info);
1211 	if (ACPI_FAILURE(status))
1212 		return AE_OK;
1213 
1214 	if (!(info->valid & ACPI_VALID_HID))
1215 		goto smo88xx_not_found;
1216 
1217 	hid = info->hardware_id.string;
1218 	if (!hid)
1219 		goto smo88xx_not_found;
1220 
1221 	i = match_string(acpi_smo8800_ids, ARRAY_SIZE(acpi_smo8800_ids), hid);
1222 	if (i < 0)
1223 		goto smo88xx_not_found;
1224 
1225 	kfree(info);
1226 
1227 	*((bool *)return_value) = true;
1228 	return AE_CTRL_TERMINATE;
1229 
1230 smo88xx_not_found:
1231 	kfree(info);
1232 	return AE_OK;
1233 }
1234 
1235 static bool is_dell_system_with_lis3lv02d(void)
1236 {
1237 	bool found;
1238 	const char *vendor;
1239 
1240 	vendor = dmi_get_system_info(DMI_SYS_VENDOR);
1241 	if (!vendor || strcmp(vendor, "Dell Inc."))
1242 		return false;
1243 
1244 	/*
1245 	 * Check that ACPI device SMO88xx is present and is functioning.
1246 	 * Function acpi_get_devices() already filters all ACPI devices
1247 	 * which are not present or are not functioning.
1248 	 * ACPI device SMO88xx represents our ST microelectronics lis3lv02d
1249 	 * accelerometer but unfortunately ACPI does not provide any other
1250 	 * information (like I2C address).
1251 	 */
1252 	found = false;
1253 	acpi_get_devices(NULL, check_acpi_smo88xx_device, NULL,
1254 			 (void **)&found);
1255 
1256 	return found;
1257 }
1258 
1259 /*
1260  * Accelerometer's I2C address is not specified in DMI nor ACPI,
1261  * so it is needed to define mapping table based on DMI product names.
1262  */
1263 static const struct {
1264 	const char *dmi_product_name;
1265 	unsigned short i2c_addr;
1266 } dell_lis3lv02d_devices[] = {
1267 	/*
1268 	 * Dell platform team told us that these Latitude devices have
1269 	 * ST microelectronics accelerometer at I2C address 0x29.
1270 	 */
1271 	{ "Latitude E5250",     0x29 },
1272 	{ "Latitude E5450",     0x29 },
1273 	{ "Latitude E5550",     0x29 },
1274 	{ "Latitude E6440",     0x29 },
1275 	{ "Latitude E6440 ATG", 0x29 },
1276 	{ "Latitude E6540",     0x29 },
1277 	/*
1278 	 * Additional individual entries were added after verification.
1279 	 */
1280 	{ "Latitude 5480",      0x29 },
1281 	{ "Vostro V131",        0x1d },
1282 };
1283 
1284 static void register_dell_lis3lv02d_i2c_device(struct i801_priv *priv)
1285 {
1286 	struct i2c_board_info info;
1287 	const char *dmi_product_name;
1288 	int i;
1289 
1290 	dmi_product_name = dmi_get_system_info(DMI_PRODUCT_NAME);
1291 	for (i = 0; i < ARRAY_SIZE(dell_lis3lv02d_devices); ++i) {
1292 		if (strcmp(dmi_product_name,
1293 			   dell_lis3lv02d_devices[i].dmi_product_name) == 0)
1294 			break;
1295 	}
1296 
1297 	if (i == ARRAY_SIZE(dell_lis3lv02d_devices)) {
1298 		dev_warn(&priv->pci_dev->dev,
1299 			 "Accelerometer lis3lv02d is present on SMBus but its"
1300 			 " address is unknown, skipping registration\n");
1301 		return;
1302 	}
1303 
1304 	memset(&info, 0, sizeof(struct i2c_board_info));
1305 	info.addr = dell_lis3lv02d_devices[i].i2c_addr;
1306 	strlcpy(info.type, "lis3lv02d", I2C_NAME_SIZE);
1307 	i2c_new_client_device(&priv->adapter, &info);
1308 }
1309 
1310 /* Register optional slaves */
1311 static void i801_probe_optional_slaves(struct i801_priv *priv)
1312 {
1313 	/* Only register slaves on main SMBus channel */
1314 	if (priv->features & FEATURE_IDF)
1315 		return;
1316 
1317 	if (apanel_addr) {
1318 		struct i2c_board_info info;
1319 
1320 		memset(&info, 0, sizeof(struct i2c_board_info));
1321 		info.addr = apanel_addr;
1322 		strlcpy(info.type, "fujitsu_apanel", I2C_NAME_SIZE);
1323 		i2c_new_client_device(&priv->adapter, &info);
1324 	}
1325 
1326 	if (dmi_name_in_vendors("FUJITSU"))
1327 		dmi_walk(dmi_check_onboard_devices, &priv->adapter);
1328 
1329 	if (is_dell_system_with_lis3lv02d())
1330 		register_dell_lis3lv02d_i2c_device(priv);
1331 
1332 	/* Instantiate SPD EEPROMs unless the SMBus is multiplexed */
1333 #if IS_ENABLED(CONFIG_I2C_MUX_GPIO)
1334 	if (!priv->mux_drvdata)
1335 #endif
1336 		i2c_register_spd(&priv->adapter);
1337 }
1338 #else
1339 static void __init input_apanel_init(void) {}
1340 static void i801_probe_optional_slaves(struct i801_priv *priv) {}
1341 #endif	/* CONFIG_X86 && CONFIG_DMI */
1342 
1343 #if IS_ENABLED(CONFIG_I2C_MUX_GPIO) && defined CONFIG_DMI
1344 static struct i801_mux_config i801_mux_config_asus_z8_d12 = {
1345 	.gpio_chip = "gpio_ich",
1346 	.values = { 0x02, 0x03 },
1347 	.n_values = 2,
1348 	.classes = { I2C_CLASS_SPD, I2C_CLASS_SPD },
1349 	.gpios = { 52, 53 },
1350 	.n_gpios = 2,
1351 };
1352 
1353 static struct i801_mux_config i801_mux_config_asus_z8_d18 = {
1354 	.gpio_chip = "gpio_ich",
1355 	.values = { 0x02, 0x03, 0x01 },
1356 	.n_values = 3,
1357 	.classes = { I2C_CLASS_SPD, I2C_CLASS_SPD, I2C_CLASS_SPD },
1358 	.gpios = { 52, 53 },
1359 	.n_gpios = 2,
1360 };
1361 
1362 static const struct dmi_system_id mux_dmi_table[] = {
1363 	{
1364 		.matches = {
1365 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1366 			DMI_MATCH(DMI_BOARD_NAME, "Z8NA-D6(C)"),
1367 		},
1368 		.driver_data = &i801_mux_config_asus_z8_d12,
1369 	},
1370 	{
1371 		.matches = {
1372 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1373 			DMI_MATCH(DMI_BOARD_NAME, "Z8P(N)E-D12(X)"),
1374 		},
1375 		.driver_data = &i801_mux_config_asus_z8_d12,
1376 	},
1377 	{
1378 		.matches = {
1379 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1380 			DMI_MATCH(DMI_BOARD_NAME, "Z8NH-D12"),
1381 		},
1382 		.driver_data = &i801_mux_config_asus_z8_d12,
1383 	},
1384 	{
1385 		.matches = {
1386 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1387 			DMI_MATCH(DMI_BOARD_NAME, "Z8PH-D12/IFB"),
1388 		},
1389 		.driver_data = &i801_mux_config_asus_z8_d12,
1390 	},
1391 	{
1392 		.matches = {
1393 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1394 			DMI_MATCH(DMI_BOARD_NAME, "Z8NR-D12"),
1395 		},
1396 		.driver_data = &i801_mux_config_asus_z8_d12,
1397 	},
1398 	{
1399 		.matches = {
1400 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1401 			DMI_MATCH(DMI_BOARD_NAME, "Z8P(N)H-D12"),
1402 		},
1403 		.driver_data = &i801_mux_config_asus_z8_d12,
1404 	},
1405 	{
1406 		.matches = {
1407 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1408 			DMI_MATCH(DMI_BOARD_NAME, "Z8PG-D18"),
1409 		},
1410 		.driver_data = &i801_mux_config_asus_z8_d18,
1411 	},
1412 	{
1413 		.matches = {
1414 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1415 			DMI_MATCH(DMI_BOARD_NAME, "Z8PE-D18"),
1416 		},
1417 		.driver_data = &i801_mux_config_asus_z8_d18,
1418 	},
1419 	{
1420 		.matches = {
1421 			DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1422 			DMI_MATCH(DMI_BOARD_NAME, "Z8PS-D12"),
1423 		},
1424 		.driver_data = &i801_mux_config_asus_z8_d12,
1425 	},
1426 	{ }
1427 };
1428 
1429 /* Setup multiplexing if needed */
1430 static int i801_add_mux(struct i801_priv *priv)
1431 {
1432 	struct device *dev = &priv->adapter.dev;
1433 	const struct i801_mux_config *mux_config;
1434 	struct i2c_mux_gpio_platform_data gpio_data;
1435 	struct gpiod_lookup_table *lookup;
1436 	int err, i;
1437 
1438 	if (!priv->mux_drvdata)
1439 		return 0;
1440 	mux_config = priv->mux_drvdata;
1441 
1442 	/* Prepare the platform data */
1443 	memset(&gpio_data, 0, sizeof(struct i2c_mux_gpio_platform_data));
1444 	gpio_data.parent = priv->adapter.nr;
1445 	gpio_data.values = mux_config->values;
1446 	gpio_data.n_values = mux_config->n_values;
1447 	gpio_data.classes = mux_config->classes;
1448 	gpio_data.idle = I2C_MUX_GPIO_NO_IDLE;
1449 
1450 	/* Register GPIO descriptor lookup table */
1451 	lookup = devm_kzalloc(dev,
1452 			      struct_size(lookup, table, mux_config->n_gpios),
1453 			      GFP_KERNEL);
1454 	if (!lookup)
1455 		return -ENOMEM;
1456 	lookup->dev_id = "i2c-mux-gpio";
1457 	for (i = 0; i < mux_config->n_gpios; i++) {
1458 		lookup->table[i] = (struct gpiod_lookup)
1459 			GPIO_LOOKUP(mux_config->gpio_chip,
1460 				    mux_config->gpios[i], "mux", 0);
1461 	}
1462 	gpiod_add_lookup_table(lookup);
1463 	priv->lookup = lookup;
1464 
1465 	/*
1466 	 * Register the mux device, we use PLATFORM_DEVID_NONE here
1467 	 * because since we are referring to the GPIO chip by name we are
1468 	 * anyways in deep trouble if there is more than one of these
1469 	 * devices, and there should likely only be one platform controller
1470 	 * hub.
1471 	 */
1472 	priv->mux_pdev = platform_device_register_data(dev, "i2c-mux-gpio",
1473 				PLATFORM_DEVID_NONE, &gpio_data,
1474 				sizeof(struct i2c_mux_gpio_platform_data));
1475 	if (IS_ERR(priv->mux_pdev)) {
1476 		err = PTR_ERR(priv->mux_pdev);
1477 		gpiod_remove_lookup_table(lookup);
1478 		priv->mux_pdev = NULL;
1479 		dev_err(dev, "Failed to register i2c-mux-gpio device\n");
1480 		return err;
1481 	}
1482 
1483 	return 0;
1484 }
1485 
1486 static void i801_del_mux(struct i801_priv *priv)
1487 {
1488 	if (priv->mux_pdev)
1489 		platform_device_unregister(priv->mux_pdev);
1490 	if (priv->lookup)
1491 		gpiod_remove_lookup_table(priv->lookup);
1492 }
1493 
1494 static unsigned int i801_get_adapter_class(struct i801_priv *priv)
1495 {
1496 	const struct dmi_system_id *id;
1497 	const struct i801_mux_config *mux_config;
1498 	unsigned int class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
1499 	int i;
1500 
1501 	id = dmi_first_match(mux_dmi_table);
1502 	if (id) {
1503 		/* Remove branch classes from trunk */
1504 		mux_config = id->driver_data;
1505 		for (i = 0; i < mux_config->n_values; i++)
1506 			class &= ~mux_config->classes[i];
1507 
1508 		/* Remember for later */
1509 		priv->mux_drvdata = mux_config;
1510 	}
1511 
1512 	return class;
1513 }
1514 #else
1515 static inline int i801_add_mux(struct i801_priv *priv) { return 0; }
1516 static inline void i801_del_mux(struct i801_priv *priv) { }
1517 
1518 static inline unsigned int i801_get_adapter_class(struct i801_priv *priv)
1519 {
1520 	return I2C_CLASS_HWMON | I2C_CLASS_SPD;
1521 }
1522 #endif
1523 
1524 static const struct itco_wdt_platform_data spt_tco_platform_data = {
1525 	.name = "Intel PCH",
1526 	.version = 4,
1527 };
1528 
1529 static DEFINE_SPINLOCK(p2sb_spinlock);
1530 
1531 static struct platform_device *
1532 i801_add_tco_spt(struct i801_priv *priv, struct pci_dev *pci_dev,
1533 		 struct resource *tco_res)
1534 {
1535 	struct resource *res;
1536 	unsigned int devfn;
1537 	u64 base64_addr;
1538 	u32 base_addr;
1539 	u8 hidden;
1540 
1541 	/*
1542 	 * We must access the NO_REBOOT bit over the Primary to Sideband
1543 	 * bridge (P2SB). The BIOS prevents the P2SB device from being
1544 	 * enumerated by the PCI subsystem, so we need to unhide/hide it
1545 	 * to lookup the P2SB BAR.
1546 	 */
1547 	spin_lock(&p2sb_spinlock);
1548 
1549 	devfn = PCI_DEVFN(PCI_SLOT(pci_dev->devfn), 1);
1550 
1551 	/* Unhide the P2SB device, if it is hidden */
1552 	pci_bus_read_config_byte(pci_dev->bus, devfn, 0xe1, &hidden);
1553 	if (hidden)
1554 		pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, 0x0);
1555 
1556 	pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR, &base_addr);
1557 	base64_addr = base_addr & 0xfffffff0;
1558 
1559 	pci_bus_read_config_dword(pci_dev->bus, devfn, SBREG_BAR + 0x4, &base_addr);
1560 	base64_addr |= (u64)base_addr << 32;
1561 
1562 	/* Hide the P2SB device, if it was hidden before */
1563 	if (hidden)
1564 		pci_bus_write_config_byte(pci_dev->bus, devfn, 0xe1, hidden);
1565 	spin_unlock(&p2sb_spinlock);
1566 
1567 	res = &tco_res[1];
1568 	if (pci_dev->device == PCI_DEVICE_ID_INTEL_DNV_SMBUS)
1569 		res->start = (resource_size_t)base64_addr + SBREG_SMBCTRL_DNV;
1570 	else
1571 		res->start = (resource_size_t)base64_addr + SBREG_SMBCTRL;
1572 
1573 	res->end = res->start + 3;
1574 	res->flags = IORESOURCE_MEM;
1575 
1576 	return platform_device_register_resndata(&pci_dev->dev, "iTCO_wdt", -1,
1577 					tco_res, 2, &spt_tco_platform_data,
1578 					sizeof(spt_tco_platform_data));
1579 }
1580 
1581 static const struct itco_wdt_platform_data cnl_tco_platform_data = {
1582 	.name = "Intel PCH",
1583 	.version = 6,
1584 };
1585 
1586 static struct platform_device *
1587 i801_add_tco_cnl(struct i801_priv *priv, struct pci_dev *pci_dev,
1588 		 struct resource *tco_res)
1589 {
1590 	return platform_device_register_resndata(&pci_dev->dev,
1591 			"iTCO_wdt", -1, tco_res, 1, &cnl_tco_platform_data,
1592 			sizeof(cnl_tco_platform_data));
1593 }
1594 
1595 static void i801_add_tco(struct i801_priv *priv)
1596 {
1597 	struct pci_dev *pci_dev = priv->pci_dev;
1598 	struct resource tco_res[2], *res;
1599 	u32 tco_base, tco_ctl;
1600 
1601 	/* If we have ACPI based watchdog use that instead */
1602 	if (acpi_has_watchdog())
1603 		return;
1604 
1605 	if (!(priv->features & (FEATURE_TCO_SPT | FEATURE_TCO_CNL)))
1606 		return;
1607 
1608 	pci_read_config_dword(pci_dev, TCOBASE, &tco_base);
1609 	pci_read_config_dword(pci_dev, TCOCTL, &tco_ctl);
1610 	if (!(tco_ctl & TCOCTL_EN))
1611 		return;
1612 
1613 	memset(tco_res, 0, sizeof(tco_res));
1614 	/*
1615 	 * Always populate the main iTCO IO resource here. The second entry
1616 	 * for NO_REBOOT MMIO is filled by the SPT specific function.
1617 	 */
1618 	res = &tco_res[0];
1619 	res->start = tco_base & ~1;
1620 	res->end = res->start + 32 - 1;
1621 	res->flags = IORESOURCE_IO;
1622 
1623 	if (priv->features & FEATURE_TCO_CNL)
1624 		priv->tco_pdev = i801_add_tco_cnl(priv, pci_dev, tco_res);
1625 	else
1626 		priv->tco_pdev = i801_add_tco_spt(priv, pci_dev, tco_res);
1627 
1628 	if (IS_ERR(priv->tco_pdev))
1629 		dev_warn(&pci_dev->dev, "failed to create iTCO device\n");
1630 }
1631 
1632 #ifdef CONFIG_ACPI
1633 static bool i801_acpi_is_smbus_ioport(const struct i801_priv *priv,
1634 				      acpi_physical_address address)
1635 {
1636 	return address >= priv->smba &&
1637 	       address <= pci_resource_end(priv->pci_dev, SMBBAR);
1638 }
1639 
1640 static acpi_status
1641 i801_acpi_io_handler(u32 function, acpi_physical_address address, u32 bits,
1642 		     u64 *value, void *handler_context, void *region_context)
1643 {
1644 	struct i801_priv *priv = handler_context;
1645 	struct pci_dev *pdev = priv->pci_dev;
1646 	acpi_status status;
1647 
1648 	/*
1649 	 * Once BIOS AML code touches the OpRegion we warn and inhibit any
1650 	 * further access from the driver itself. This device is now owned
1651 	 * by the system firmware.
1652 	 */
1653 	mutex_lock(&priv->acpi_lock);
1654 
1655 	if (!priv->acpi_reserved && i801_acpi_is_smbus_ioport(priv, address)) {
1656 		priv->acpi_reserved = true;
1657 
1658 		dev_warn(&pdev->dev, "BIOS is accessing SMBus registers\n");
1659 		dev_warn(&pdev->dev, "Driver SMBus register access inhibited\n");
1660 
1661 		/*
1662 		 * BIOS is accessing the host controller so prevent it from
1663 		 * suspending automatically from now on.
1664 		 */
1665 		pm_runtime_get_sync(&pdev->dev);
1666 	}
1667 
1668 	if ((function & ACPI_IO_MASK) == ACPI_READ)
1669 		status = acpi_os_read_port(address, (u32 *)value, bits);
1670 	else
1671 		status = acpi_os_write_port(address, (u32)*value, bits);
1672 
1673 	mutex_unlock(&priv->acpi_lock);
1674 
1675 	return status;
1676 }
1677 
1678 static int i801_acpi_probe(struct i801_priv *priv)
1679 {
1680 	struct acpi_device *adev;
1681 	acpi_status status;
1682 
1683 	adev = ACPI_COMPANION(&priv->pci_dev->dev);
1684 	if (adev) {
1685 		status = acpi_install_address_space_handler(adev->handle,
1686 				ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler,
1687 				NULL, priv);
1688 		if (ACPI_SUCCESS(status))
1689 			return 0;
1690 	}
1691 
1692 	return acpi_check_resource_conflict(&priv->pci_dev->resource[SMBBAR]);
1693 }
1694 
1695 static void i801_acpi_remove(struct i801_priv *priv)
1696 {
1697 	struct acpi_device *adev;
1698 
1699 	adev = ACPI_COMPANION(&priv->pci_dev->dev);
1700 	if (!adev)
1701 		return;
1702 
1703 	acpi_remove_address_space_handler(adev->handle,
1704 		ACPI_ADR_SPACE_SYSTEM_IO, i801_acpi_io_handler);
1705 
1706 	mutex_lock(&priv->acpi_lock);
1707 	if (priv->acpi_reserved)
1708 		pm_runtime_put(&priv->pci_dev->dev);
1709 	mutex_unlock(&priv->acpi_lock);
1710 }
1711 #else
1712 static inline int i801_acpi_probe(struct i801_priv *priv) { return 0; }
1713 static inline void i801_acpi_remove(struct i801_priv *priv) { }
1714 #endif
1715 
1716 static unsigned char i801_setup_hstcfg(struct i801_priv *priv)
1717 {
1718 	unsigned char hstcfg = priv->original_hstcfg;
1719 
1720 	hstcfg &= ~SMBHSTCFG_I2C_EN;	/* SMBus timing */
1721 	hstcfg |= SMBHSTCFG_HST_EN;
1722 	pci_write_config_byte(priv->pci_dev, SMBHSTCFG, hstcfg);
1723 	return hstcfg;
1724 }
1725 
1726 static int i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
1727 {
1728 	unsigned char temp;
1729 	int err, i;
1730 	struct i801_priv *priv;
1731 
1732 	priv = devm_kzalloc(&dev->dev, sizeof(*priv), GFP_KERNEL);
1733 	if (!priv)
1734 		return -ENOMEM;
1735 
1736 	i2c_set_adapdata(&priv->adapter, priv);
1737 	priv->adapter.owner = THIS_MODULE;
1738 	priv->adapter.class = i801_get_adapter_class(priv);
1739 	priv->adapter.algo = &smbus_algorithm;
1740 	priv->adapter.dev.parent = &dev->dev;
1741 	ACPI_COMPANION_SET(&priv->adapter.dev, ACPI_COMPANION(&dev->dev));
1742 	priv->adapter.retries = 3;
1743 	mutex_init(&priv->acpi_lock);
1744 
1745 	priv->pci_dev = dev;
1746 	switch (dev->device) {
1747 	case PCI_DEVICE_ID_INTEL_SUNRISEPOINT_H_SMBUS:
1748 	case PCI_DEVICE_ID_INTEL_SUNRISEPOINT_LP_SMBUS:
1749 	case PCI_DEVICE_ID_INTEL_LEWISBURG_SMBUS:
1750 	case PCI_DEVICE_ID_INTEL_LEWISBURG_SSKU_SMBUS:
1751 	case PCI_DEVICE_ID_INTEL_DNV_SMBUS:
1752 	case PCI_DEVICE_ID_INTEL_KABYLAKE_PCH_H_SMBUS:
1753 	case PCI_DEVICE_ID_INTEL_COMETLAKE_V_SMBUS:
1754 		priv->features |= FEATURE_BLOCK_PROC;
1755 		priv->features |= FEATURE_I2C_BLOCK_READ;
1756 		priv->features |= FEATURE_IRQ;
1757 		priv->features |= FEATURE_SMBUS_PEC;
1758 		priv->features |= FEATURE_BLOCK_BUFFER;
1759 		priv->features |= FEATURE_TCO_SPT;
1760 		priv->features |= FEATURE_HOST_NOTIFY;
1761 		break;
1762 
1763 	case PCI_DEVICE_ID_INTEL_CANNONLAKE_H_SMBUS:
1764 	case PCI_DEVICE_ID_INTEL_CANNONLAKE_LP_SMBUS:
1765 	case PCI_DEVICE_ID_INTEL_CDF_SMBUS:
1766 	case PCI_DEVICE_ID_INTEL_ICELAKE_LP_SMBUS:
1767 	case PCI_DEVICE_ID_INTEL_COMETLAKE_SMBUS:
1768 	case PCI_DEVICE_ID_INTEL_COMETLAKE_H_SMBUS:
1769 	case PCI_DEVICE_ID_INTEL_ELKHART_LAKE_SMBUS:
1770 	case PCI_DEVICE_ID_INTEL_TIGERLAKE_LP_SMBUS:
1771 	case PCI_DEVICE_ID_INTEL_TIGERLAKE_H_SMBUS:
1772 	case PCI_DEVICE_ID_INTEL_JASPER_LAKE_SMBUS:
1773 	case PCI_DEVICE_ID_INTEL_EBG_SMBUS:
1774 	case PCI_DEVICE_ID_INTEL_ALDER_LAKE_S_SMBUS:
1775 		priv->features |= FEATURE_BLOCK_PROC;
1776 		priv->features |= FEATURE_I2C_BLOCK_READ;
1777 		priv->features |= FEATURE_IRQ;
1778 		priv->features |= FEATURE_SMBUS_PEC;
1779 		priv->features |= FEATURE_BLOCK_BUFFER;
1780 		priv->features |= FEATURE_TCO_CNL;
1781 		priv->features |= FEATURE_HOST_NOTIFY;
1782 		break;
1783 
1784 	case PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0:
1785 	case PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1:
1786 	case PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2:
1787 	case PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS0:
1788 	case PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1:
1789 	case PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2:
1790 		priv->features |= FEATURE_IDF;
1791 		fallthrough;
1792 	default:
1793 		priv->features |= FEATURE_BLOCK_PROC;
1794 		priv->features |= FEATURE_I2C_BLOCK_READ;
1795 		priv->features |= FEATURE_IRQ;
1796 		fallthrough;
1797 	case PCI_DEVICE_ID_INTEL_82801DB_3:
1798 		priv->features |= FEATURE_SMBUS_PEC;
1799 		priv->features |= FEATURE_BLOCK_BUFFER;
1800 		fallthrough;
1801 	case PCI_DEVICE_ID_INTEL_82801CA_3:
1802 		priv->features |= FEATURE_HOST_NOTIFY;
1803 		fallthrough;
1804 	case PCI_DEVICE_ID_INTEL_82801BA_2:
1805 	case PCI_DEVICE_ID_INTEL_82801AB_3:
1806 	case PCI_DEVICE_ID_INTEL_82801AA_3:
1807 		break;
1808 	}
1809 
1810 	/* Disable features on user request */
1811 	for (i = 0; i < ARRAY_SIZE(i801_feature_names); i++) {
1812 		if (priv->features & disable_features & (1 << i))
1813 			dev_notice(&dev->dev, "%s disabled by user\n",
1814 				   i801_feature_names[i]);
1815 	}
1816 	priv->features &= ~disable_features;
1817 
1818 	err = pcim_enable_device(dev);
1819 	if (err) {
1820 		dev_err(&dev->dev, "Failed to enable SMBus PCI device (%d)\n",
1821 			err);
1822 		return err;
1823 	}
1824 	pcim_pin_device(dev);
1825 
1826 	/* Determine the address of the SMBus area */
1827 	priv->smba = pci_resource_start(dev, SMBBAR);
1828 	if (!priv->smba) {
1829 		dev_err(&dev->dev,
1830 			"SMBus base address uninitialized, upgrade BIOS\n");
1831 		return -ENODEV;
1832 	}
1833 
1834 	if (i801_acpi_probe(priv))
1835 		return -ENODEV;
1836 
1837 	err = pcim_iomap_regions(dev, 1 << SMBBAR,
1838 				 dev_driver_string(&dev->dev));
1839 	if (err) {
1840 		dev_err(&dev->dev,
1841 			"Failed to request SMBus region 0x%lx-0x%Lx\n",
1842 			priv->smba,
1843 			(unsigned long long)pci_resource_end(dev, SMBBAR));
1844 		i801_acpi_remove(priv);
1845 		return err;
1846 	}
1847 
1848 	pci_read_config_byte(priv->pci_dev, SMBHSTCFG, &priv->original_hstcfg);
1849 	temp = i801_setup_hstcfg(priv);
1850 	if (!(priv->original_hstcfg & SMBHSTCFG_HST_EN))
1851 		dev_info(&dev->dev, "Enabling SMBus device\n");
1852 
1853 	if (temp & SMBHSTCFG_SMB_SMI_EN) {
1854 		dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n");
1855 		/* Disable SMBus interrupt feature if SMBus using SMI# */
1856 		priv->features &= ~FEATURE_IRQ;
1857 	}
1858 	if (temp & SMBHSTCFG_SPD_WD)
1859 		dev_info(&dev->dev, "SPD Write Disable is set\n");
1860 
1861 	/* Clear special mode bits */
1862 	if (priv->features & (FEATURE_SMBUS_PEC | FEATURE_BLOCK_BUFFER))
1863 		outb_p(inb_p(SMBAUXCTL(priv)) &
1864 		       ~(SMBAUXCTL_CRC | SMBAUXCTL_E32B), SMBAUXCTL(priv));
1865 
1866 	/* Remember original Host Notify setting */
1867 	if (priv->features & FEATURE_HOST_NOTIFY)
1868 		priv->original_slvcmd = inb_p(SMBSLVCMD(priv));
1869 
1870 	/* Default timeout in interrupt mode: 200 ms */
1871 	priv->adapter.timeout = HZ / 5;
1872 
1873 	if (dev->irq == IRQ_NOTCONNECTED)
1874 		priv->features &= ~FEATURE_IRQ;
1875 
1876 	if (priv->features & FEATURE_IRQ) {
1877 		u16 pcictl, pcists;
1878 
1879 		/* Complain if an interrupt is already pending */
1880 		pci_read_config_word(priv->pci_dev, SMBPCISTS, &pcists);
1881 		if (pcists & SMBPCISTS_INTS)
1882 			dev_warn(&dev->dev, "An interrupt is pending!\n");
1883 
1884 		/* Check if interrupts have been disabled */
1885 		pci_read_config_word(priv->pci_dev, SMBPCICTL, &pcictl);
1886 		if (pcictl & SMBPCICTL_INTDIS) {
1887 			dev_info(&dev->dev, "Interrupts are disabled\n");
1888 			priv->features &= ~FEATURE_IRQ;
1889 		}
1890 	}
1891 
1892 	if (priv->features & FEATURE_IRQ) {
1893 		init_waitqueue_head(&priv->waitq);
1894 
1895 		err = devm_request_irq(&dev->dev, dev->irq, i801_isr,
1896 				       IRQF_SHARED,
1897 				       dev_driver_string(&dev->dev), priv);
1898 		if (err) {
1899 			dev_err(&dev->dev, "Failed to allocate irq %d: %d\n",
1900 				dev->irq, err);
1901 			priv->features &= ~FEATURE_IRQ;
1902 		}
1903 	}
1904 	dev_info(&dev->dev, "SMBus using %s\n",
1905 		 priv->features & FEATURE_IRQ ? "PCI interrupt" : "polling");
1906 
1907 	i801_add_tco(priv);
1908 
1909 	snprintf(priv->adapter.name, sizeof(priv->adapter.name),
1910 		"SMBus I801 adapter at %04lx", priv->smba);
1911 	err = i2c_add_adapter(&priv->adapter);
1912 	if (err) {
1913 		i801_acpi_remove(priv);
1914 		return err;
1915 	}
1916 
1917 	i801_enable_host_notify(&priv->adapter);
1918 
1919 	i801_probe_optional_slaves(priv);
1920 	/* We ignore errors - multiplexing is optional */
1921 	i801_add_mux(priv);
1922 
1923 	pci_set_drvdata(dev, priv);
1924 
1925 	dev_pm_set_driver_flags(&dev->dev, DPM_FLAG_NO_DIRECT_COMPLETE);
1926 	pm_runtime_set_autosuspend_delay(&dev->dev, 1000);
1927 	pm_runtime_use_autosuspend(&dev->dev);
1928 	pm_runtime_put_autosuspend(&dev->dev);
1929 	pm_runtime_allow(&dev->dev);
1930 
1931 	return 0;
1932 }
1933 
1934 static void i801_remove(struct pci_dev *dev)
1935 {
1936 	struct i801_priv *priv = pci_get_drvdata(dev);
1937 
1938 	pm_runtime_forbid(&dev->dev);
1939 	pm_runtime_get_noresume(&dev->dev);
1940 
1941 	i801_disable_host_notify(priv);
1942 	i801_del_mux(priv);
1943 	i2c_del_adapter(&priv->adapter);
1944 	i801_acpi_remove(priv);
1945 	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
1946 
1947 	platform_device_unregister(priv->tco_pdev);
1948 
1949 	/*
1950 	 * do not call pci_disable_device(dev) since it can cause hard hangs on
1951 	 * some systems during power-off (eg. Fujitsu-Siemens Lifebook E8010)
1952 	 */
1953 }
1954 
1955 static void i801_shutdown(struct pci_dev *dev)
1956 {
1957 	struct i801_priv *priv = pci_get_drvdata(dev);
1958 
1959 	/* Restore config registers to avoid hard hang on some systems */
1960 	i801_disable_host_notify(priv);
1961 	pci_write_config_byte(dev, SMBHSTCFG, priv->original_hstcfg);
1962 }
1963 
1964 #ifdef CONFIG_PM_SLEEP
1965 static int i801_suspend(struct device *dev)
1966 {
1967 	struct i801_priv *priv = dev_get_drvdata(dev);
1968 
1969 	pci_write_config_byte(priv->pci_dev, SMBHSTCFG, priv->original_hstcfg);
1970 	return 0;
1971 }
1972 
1973 static int i801_resume(struct device *dev)
1974 {
1975 	struct i801_priv *priv = dev_get_drvdata(dev);
1976 
1977 	i801_setup_hstcfg(priv);
1978 	i801_enable_host_notify(&priv->adapter);
1979 
1980 	return 0;
1981 }
1982 #endif
1983 
1984 static SIMPLE_DEV_PM_OPS(i801_pm_ops, i801_suspend, i801_resume);
1985 
1986 static struct pci_driver i801_driver = {
1987 	.name		= "i801_smbus",
1988 	.id_table	= i801_ids,
1989 	.probe		= i801_probe,
1990 	.remove		= i801_remove,
1991 	.shutdown	= i801_shutdown,
1992 	.driver		= {
1993 		.pm	= &i801_pm_ops,
1994 	},
1995 };
1996 
1997 static int __init i2c_i801_init(void)
1998 {
1999 	if (dmi_name_in_vendors("FUJITSU"))
2000 		input_apanel_init();
2001 	return pci_register_driver(&i801_driver);
2002 }
2003 
2004 static void __exit i2c_i801_exit(void)
2005 {
2006 	pci_unregister_driver(&i801_driver);
2007 }
2008 
2009 MODULE_AUTHOR("Mark D. Studebaker <mdsxyz123@yahoo.com>");
2010 MODULE_AUTHOR("Jean Delvare <jdelvare@suse.de>");
2011 MODULE_DESCRIPTION("I801 SMBus driver");
2012 MODULE_LICENSE("GPL");
2013 
2014 module_init(i2c_i801_init);
2015 module_exit(i2c_i801_exit);
2016