1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Synopsys DesignWare I2C adapter driver (master only).
4  *
5  * Based on the TI DAVINCI I2C adapter driver.
6  *
7  * Copyright (C) 2006 Texas Instruments.
8  * Copyright (C) 2007 MontaVista Software Inc.
9  * Copyright (C) 2009 Provigent Ltd.
10  * Copyright (C) 2011, 2015, 2016 Intel Corporation.
11  */
12 #include <linux/acpi.h>
13 #include <linux/delay.h>
14 #include <linux/err.h>
15 #include <linux/errno.h>
16 #include <linux/i2c.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/pci.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/sched.h>
24 #include <linux/slab.h>
25 
26 #include "i2c-designware-core.h"
27 
28 #define DRIVER_NAME "i2c-designware-pci"
29 #define AMD_CLK_RATE_HZ	100000
30 
31 enum dw_pci_ctl_id_t {
32 	medfield,
33 	merrifield,
34 	baytrail,
35 	cherrytrail,
36 	haswell,
37 	elkhartlake,
38 	navi_amd,
39 };
40 
41 /*
42  * This is a legacy structure to describe the hardware counters
43  * to configure signal timings on the bus. For Device Tree platforms
44  * one should use the respective properties and for ACPI there is
45  * a set of ACPI methods that provide these counters. No new
46  * platform should use this structure.
47  */
48 struct dw_scl_sda_cfg {
49 	u16 ss_hcnt;
50 	u16 fs_hcnt;
51 	u16 ss_lcnt;
52 	u16 fs_lcnt;
53 	u32 sda_hold;
54 };
55 
56 struct dw_pci_controller {
57 	u32 bus_num;
58 	u32 flags;
59 	struct dw_scl_sda_cfg *scl_sda_cfg;
60 	int (*setup)(struct pci_dev *pdev, struct dw_pci_controller *c);
61 	u32 (*get_clk_rate_khz)(struct dw_i2c_dev *dev);
62 };
63 
64 /* Merrifield HCNT/LCNT/SDA hold time */
65 static struct dw_scl_sda_cfg mrfld_config = {
66 	.ss_hcnt = 0x2f8,
67 	.fs_hcnt = 0x87,
68 	.ss_lcnt = 0x37b,
69 	.fs_lcnt = 0x10a,
70 };
71 
72 /* BayTrail HCNT/LCNT/SDA hold time */
73 static struct dw_scl_sda_cfg byt_config = {
74 	.ss_hcnt = 0x200,
75 	.fs_hcnt = 0x55,
76 	.ss_lcnt = 0x200,
77 	.fs_lcnt = 0x99,
78 	.sda_hold = 0x6,
79 };
80 
81 /* Haswell HCNT/LCNT/SDA hold time */
82 static struct dw_scl_sda_cfg hsw_config = {
83 	.ss_hcnt = 0x01b0,
84 	.fs_hcnt = 0x48,
85 	.ss_lcnt = 0x01fb,
86 	.fs_lcnt = 0xa0,
87 	.sda_hold = 0x9,
88 };
89 
90 /* NAVI-AMD HCNT/LCNT/SDA hold time */
91 static struct dw_scl_sda_cfg navi_amd_config = {
92 	.ss_hcnt = 0x1ae,
93 	.ss_lcnt = 0x23a,
94 	.sda_hold = 0x9,
95 };
96 
97 static u32 mfld_get_clk_rate_khz(struct dw_i2c_dev *dev)
98 {
99 	return 25000;
100 }
101 
102 static u32 navi_amd_get_clk_rate_khz(struct dw_i2c_dev *dev)
103 {
104 	return AMD_CLK_RATE_HZ;
105 }
106 
107 static int mfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
108 {
109 	struct dw_i2c_dev *dev = dev_get_drvdata(&pdev->dev);
110 
111 	switch (pdev->device) {
112 	case 0x0817:
113 		dev->timings.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ;
114 		fallthrough;
115 	case 0x0818:
116 	case 0x0819:
117 		c->bus_num = pdev->device - 0x817 + 3;
118 		return 0;
119 	case 0x082C:
120 	case 0x082D:
121 	case 0x082E:
122 		c->bus_num = pdev->device - 0x82C + 0;
123 		return 0;
124 	}
125 	return -ENODEV;
126 }
127 
128  /*
129   * TODO find a better way how to deduplicate instantiation
130   * of USB PD slave device from nVidia GPU driver.
131   */
132 static int navi_amd_register_client(struct dw_i2c_dev *dev)
133 {
134 	struct i2c_board_info	info;
135 
136 	memset(&info, 0, sizeof(struct i2c_board_info));
137 	strscpy(info.type, "ccgx-ucsi", I2C_NAME_SIZE);
138 	info.addr = 0x08;
139 	info.irq = dev->irq;
140 
141 	dev->slave = i2c_new_client_device(&dev->adapter, &info);
142 	if (IS_ERR(dev->slave))
143 		return PTR_ERR(dev->slave);
144 
145 	return 0;
146 }
147 
148 static int navi_amd_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
149 {
150 	struct dw_i2c_dev *dev = dev_get_drvdata(&pdev->dev);
151 
152 	dev->flags |= MODEL_AMD_NAVI_GPU;
153 	dev->timings.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ;
154 	return 0;
155 }
156 
157 static int mrfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
158 {
159 	/*
160 	 * On Intel Merrifield the user visible i2c buses are enumerated
161 	 * [1..7]. So, we add 1 to shift the default range. Besides that the
162 	 * first PCI slot provides 4 functions, that's why we have to add 0 to
163 	 * the first slot and 4 to the next one.
164 	 */
165 	switch (PCI_SLOT(pdev->devfn)) {
166 	case 8:
167 		c->bus_num = PCI_FUNC(pdev->devfn) + 0 + 1;
168 		return 0;
169 	case 9:
170 		c->bus_num = PCI_FUNC(pdev->devfn) + 4 + 1;
171 		return 0;
172 	}
173 	return -ENODEV;
174 }
175 
176 static u32 ehl_get_clk_rate_khz(struct dw_i2c_dev *dev)
177 {
178 	return 100000;
179 }
180 
181 static struct dw_pci_controller dw_pci_controllers[] = {
182 	[medfield] = {
183 		.bus_num = -1,
184 		.setup = mfld_setup,
185 		.get_clk_rate_khz = mfld_get_clk_rate_khz,
186 	},
187 	[merrifield] = {
188 		.bus_num = -1,
189 		.scl_sda_cfg = &mrfld_config,
190 		.setup = mrfld_setup,
191 	},
192 	[baytrail] = {
193 		.bus_num = -1,
194 		.scl_sda_cfg = &byt_config,
195 	},
196 	[haswell] = {
197 		.bus_num = -1,
198 		.scl_sda_cfg = &hsw_config,
199 	},
200 	[cherrytrail] = {
201 		.bus_num = -1,
202 		.scl_sda_cfg = &byt_config,
203 	},
204 	[elkhartlake] = {
205 		.bus_num = -1,
206 		.get_clk_rate_khz = ehl_get_clk_rate_khz,
207 	},
208 	[navi_amd] = {
209 		.bus_num = -1,
210 		.scl_sda_cfg = &navi_amd_config,
211 		.setup =  navi_amd_setup,
212 		.get_clk_rate_khz = navi_amd_get_clk_rate_khz,
213 	},
214 };
215 
216 static int __maybe_unused i2c_dw_pci_suspend(struct device *dev)
217 {
218 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
219 
220 	i_dev->suspended = true;
221 	i_dev->disable(i_dev);
222 
223 	return 0;
224 }
225 
226 static int __maybe_unused i2c_dw_pci_resume(struct device *dev)
227 {
228 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
229 	int ret;
230 
231 	ret = i_dev->init(i_dev);
232 	i_dev->suspended = false;
233 
234 	return ret;
235 }
236 
237 static UNIVERSAL_DEV_PM_OPS(i2c_dw_pm_ops, i2c_dw_pci_suspend,
238 			    i2c_dw_pci_resume, NULL);
239 
240 static int i2c_dw_pci_probe(struct pci_dev *pdev,
241 			    const struct pci_device_id *id)
242 {
243 	struct dw_i2c_dev *dev;
244 	struct i2c_adapter *adap;
245 	int r;
246 	struct dw_pci_controller *controller;
247 	struct dw_scl_sda_cfg *cfg;
248 
249 	if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers))
250 		return dev_err_probe(&pdev->dev, -EINVAL,
251 				     "Invalid driver data %ld\n",
252 				     id->driver_data);
253 
254 	controller = &dw_pci_controllers[id->driver_data];
255 
256 	r = pcim_enable_device(pdev);
257 	if (r)
258 		return dev_err_probe(&pdev->dev, r,
259 				     "Failed to enable I2C PCI device\n");
260 
261 	pci_set_master(pdev);
262 
263 	r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
264 	if (r)
265 		return dev_err_probe(&pdev->dev, r,
266 				     "I/O memory remapping failed\n");
267 
268 	dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
269 	if (!dev)
270 		return -ENOMEM;
271 
272 	r = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
273 	if (r < 0)
274 		return r;
275 
276 	dev->get_clk_rate_khz = controller->get_clk_rate_khz;
277 	dev->timings.bus_freq_hz = I2C_MAX_FAST_MODE_FREQ;
278 	dev->base = pcim_iomap_table(pdev)[0];
279 	dev->dev = &pdev->dev;
280 	dev->irq = pci_irq_vector(pdev, 0);
281 	dev->flags |= controller->flags;
282 
283 	pci_set_drvdata(pdev, dev);
284 
285 	if (controller->setup) {
286 		r = controller->setup(pdev, controller);
287 		if (r) {
288 			pci_free_irq_vectors(pdev);
289 			return r;
290 		}
291 	}
292 
293 	i2c_dw_adjust_bus_speed(dev);
294 
295 	if (has_acpi_companion(&pdev->dev))
296 		i2c_dw_acpi_configure(&pdev->dev);
297 
298 	r = i2c_dw_validate_speed(dev);
299 	if (r) {
300 		pci_free_irq_vectors(pdev);
301 		return r;
302 	}
303 
304 	i2c_dw_configure(dev);
305 
306 	if (controller->scl_sda_cfg) {
307 		cfg = controller->scl_sda_cfg;
308 		dev->ss_hcnt = cfg->ss_hcnt;
309 		dev->fs_hcnt = cfg->fs_hcnt;
310 		dev->ss_lcnt = cfg->ss_lcnt;
311 		dev->fs_lcnt = cfg->fs_lcnt;
312 		dev->sda_hold_time = cfg->sda_hold;
313 	}
314 
315 	adap = &dev->adapter;
316 	adap->owner = THIS_MODULE;
317 	adap->class = 0;
318 	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
319 	adap->nr = controller->bus_num;
320 
321 	r = i2c_dw_probe(dev);
322 	if (r) {
323 		pci_free_irq_vectors(pdev);
324 		return r;
325 	}
326 
327 	if ((dev->flags & MODEL_MASK) == MODEL_AMD_NAVI_GPU) {
328 		r = navi_amd_register_client(dev);
329 		if (r) {
330 			dev_err(dev->dev, "register client failed with %d\n", r);
331 			return r;
332 		}
333 	}
334 
335 	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
336 	pm_runtime_use_autosuspend(&pdev->dev);
337 	pm_runtime_put_autosuspend(&pdev->dev);
338 	pm_runtime_allow(&pdev->dev);
339 
340 	return 0;
341 }
342 
343 static void i2c_dw_pci_remove(struct pci_dev *pdev)
344 {
345 	struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
346 
347 	dev->disable(dev);
348 	pm_runtime_forbid(&pdev->dev);
349 	pm_runtime_get_noresume(&pdev->dev);
350 
351 	i2c_del_adapter(&dev->adapter);
352 	devm_free_irq(&pdev->dev, dev->irq, dev);
353 	pci_free_irq_vectors(pdev);
354 }
355 
356 static const struct pci_device_id i2_designware_pci_ids[] = {
357 	/* Medfield */
358 	{ PCI_VDEVICE(INTEL, 0x0817), medfield },
359 	{ PCI_VDEVICE(INTEL, 0x0818), medfield },
360 	{ PCI_VDEVICE(INTEL, 0x0819), medfield },
361 	{ PCI_VDEVICE(INTEL, 0x082C), medfield },
362 	{ PCI_VDEVICE(INTEL, 0x082D), medfield },
363 	{ PCI_VDEVICE(INTEL, 0x082E), medfield },
364 	/* Merrifield */
365 	{ PCI_VDEVICE(INTEL, 0x1195), merrifield },
366 	{ PCI_VDEVICE(INTEL, 0x1196), merrifield },
367 	/* Baytrail */
368 	{ PCI_VDEVICE(INTEL, 0x0F41), baytrail },
369 	{ PCI_VDEVICE(INTEL, 0x0F42), baytrail },
370 	{ PCI_VDEVICE(INTEL, 0x0F43), baytrail },
371 	{ PCI_VDEVICE(INTEL, 0x0F44), baytrail },
372 	{ PCI_VDEVICE(INTEL, 0x0F45), baytrail },
373 	{ PCI_VDEVICE(INTEL, 0x0F46), baytrail },
374 	{ PCI_VDEVICE(INTEL, 0x0F47), baytrail },
375 	/* Haswell */
376 	{ PCI_VDEVICE(INTEL, 0x9c61), haswell },
377 	{ PCI_VDEVICE(INTEL, 0x9c62), haswell },
378 	/* Braswell / Cherrytrail */
379 	{ PCI_VDEVICE(INTEL, 0x22C1), cherrytrail },
380 	{ PCI_VDEVICE(INTEL, 0x22C2), cherrytrail },
381 	{ PCI_VDEVICE(INTEL, 0x22C3), cherrytrail },
382 	{ PCI_VDEVICE(INTEL, 0x22C4), cherrytrail },
383 	{ PCI_VDEVICE(INTEL, 0x22C5), cherrytrail },
384 	{ PCI_VDEVICE(INTEL, 0x22C6), cherrytrail },
385 	{ PCI_VDEVICE(INTEL, 0x22C7), cherrytrail },
386 	/* Elkhart Lake (PSE I2C) */
387 	{ PCI_VDEVICE(INTEL, 0x4bb9), elkhartlake },
388 	{ PCI_VDEVICE(INTEL, 0x4bba), elkhartlake },
389 	{ PCI_VDEVICE(INTEL, 0x4bbb), elkhartlake },
390 	{ PCI_VDEVICE(INTEL, 0x4bbc), elkhartlake },
391 	{ PCI_VDEVICE(INTEL, 0x4bbd), elkhartlake },
392 	{ PCI_VDEVICE(INTEL, 0x4bbe), elkhartlake },
393 	{ PCI_VDEVICE(INTEL, 0x4bbf), elkhartlake },
394 	{ PCI_VDEVICE(INTEL, 0x4bc0), elkhartlake },
395 	{ PCI_VDEVICE(ATI,  0x7314), navi_amd },
396 	{ PCI_VDEVICE(ATI,  0x73a4), navi_amd },
397 	{ PCI_VDEVICE(ATI,  0x73e4), navi_amd },
398 	{ PCI_VDEVICE(ATI,  0x73c4), navi_amd },
399 	{ 0,}
400 };
401 MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
402 
403 static struct pci_driver dw_i2c_driver = {
404 	.name		= DRIVER_NAME,
405 	.id_table	= i2_designware_pci_ids,
406 	.probe		= i2c_dw_pci_probe,
407 	.remove		= i2c_dw_pci_remove,
408 	.driver         = {
409 		.pm     = &i2c_dw_pm_ops,
410 	},
411 };
412 module_pci_driver(dw_i2c_driver);
413 
414 /* Work with hotplug and coldplug */
415 MODULE_ALIAS("i2c_designware-pci");
416 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
417 MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
418 MODULE_LICENSE("GPL");
419