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 
30 enum dw_pci_ctl_id_t {
31 	medfield,
32 	merrifield,
33 	baytrail,
34 	cherrytrail,
35 	haswell,
36 	elkhartlake,
37 };
38 
39 struct dw_scl_sda_cfg {
40 	u32 ss_hcnt;
41 	u32 fs_hcnt;
42 	u32 ss_lcnt;
43 	u32 fs_lcnt;
44 	u32 sda_hold;
45 };
46 
47 struct dw_pci_controller {
48 	u32 bus_num;
49 	u32 flags;
50 	struct dw_scl_sda_cfg *scl_sda_cfg;
51 	int (*setup)(struct pci_dev *pdev, struct dw_pci_controller *c);
52 	u32 (*get_clk_rate_khz)(struct dw_i2c_dev *dev);
53 };
54 
55 /* Merrifield HCNT/LCNT/SDA hold time */
56 static struct dw_scl_sda_cfg mrfld_config = {
57 	.ss_hcnt = 0x2f8,
58 	.fs_hcnt = 0x87,
59 	.ss_lcnt = 0x37b,
60 	.fs_lcnt = 0x10a,
61 };
62 
63 /* BayTrail HCNT/LCNT/SDA hold time */
64 static struct dw_scl_sda_cfg byt_config = {
65 	.ss_hcnt = 0x200,
66 	.fs_hcnt = 0x55,
67 	.ss_lcnt = 0x200,
68 	.fs_lcnt = 0x99,
69 	.sda_hold = 0x6,
70 };
71 
72 /* Haswell HCNT/LCNT/SDA hold time */
73 static struct dw_scl_sda_cfg hsw_config = {
74 	.ss_hcnt = 0x01b0,
75 	.fs_hcnt = 0x48,
76 	.ss_lcnt = 0x01fb,
77 	.fs_lcnt = 0xa0,
78 	.sda_hold = 0x9,
79 };
80 
81 static u32 mfld_get_clk_rate_khz(struct dw_i2c_dev *dev)
82 {
83 	return 25000;
84 }
85 
86 static int mfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
87 {
88 	struct dw_i2c_dev *dev = dev_get_drvdata(&pdev->dev);
89 
90 	switch (pdev->device) {
91 	case 0x0817:
92 		dev->timings.bus_freq_hz = I2C_MAX_STANDARD_MODE_FREQ;
93 		/* fall through */
94 	case 0x0818:
95 	case 0x0819:
96 		c->bus_num = pdev->device - 0x817 + 3;
97 		return 0;
98 	case 0x082C:
99 	case 0x082D:
100 	case 0x082E:
101 		c->bus_num = pdev->device - 0x82C + 0;
102 		return 0;
103 	}
104 	return -ENODEV;
105 }
106 
107 static int mrfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
108 {
109 	/*
110 	 * On Intel Merrifield the user visible i2c buses are enumerated
111 	 * [1..7]. So, we add 1 to shift the default range. Besides that the
112 	 * first PCI slot provides 4 functions, that's why we have to add 0 to
113 	 * the first slot and 4 to the next one.
114 	 */
115 	switch (PCI_SLOT(pdev->devfn)) {
116 	case 8:
117 		c->bus_num = PCI_FUNC(pdev->devfn) + 0 + 1;
118 		return 0;
119 	case 9:
120 		c->bus_num = PCI_FUNC(pdev->devfn) + 4 + 1;
121 		return 0;
122 	}
123 	return -ENODEV;
124 }
125 
126 static u32 ehl_get_clk_rate_khz(struct dw_i2c_dev *dev)
127 {
128 	return 100000;
129 }
130 
131 static struct dw_pci_controller dw_pci_controllers[] = {
132 	[medfield] = {
133 		.bus_num = -1,
134 		.setup = mfld_setup,
135 		.get_clk_rate_khz = mfld_get_clk_rate_khz,
136 	},
137 	[merrifield] = {
138 		.bus_num = -1,
139 		.scl_sda_cfg = &mrfld_config,
140 		.setup = mrfld_setup,
141 	},
142 	[baytrail] = {
143 		.bus_num = -1,
144 		.scl_sda_cfg = &byt_config,
145 	},
146 	[haswell] = {
147 		.bus_num = -1,
148 		.scl_sda_cfg = &hsw_config,
149 	},
150 	[cherrytrail] = {
151 		.bus_num = -1,
152 		.scl_sda_cfg = &byt_config,
153 	},
154 	[elkhartlake] = {
155 		.bus_num = -1,
156 		.get_clk_rate_khz = ehl_get_clk_rate_khz,
157 	},
158 };
159 
160 #ifdef CONFIG_PM
161 static int i2c_dw_pci_suspend(struct device *dev)
162 {
163 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
164 
165 	i_dev->suspended = true;
166 	i_dev->disable(i_dev);
167 
168 	return 0;
169 }
170 
171 static int i2c_dw_pci_resume(struct device *dev)
172 {
173 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
174 	int ret;
175 
176 	ret = i_dev->init(i_dev);
177 	i_dev->suspended = false;
178 
179 	return ret;
180 }
181 #endif
182 
183 static UNIVERSAL_DEV_PM_OPS(i2c_dw_pm_ops, i2c_dw_pci_suspend,
184 			    i2c_dw_pci_resume, NULL);
185 
186 static int i2c_dw_pci_probe(struct pci_dev *pdev,
187 			    const struct pci_device_id *id)
188 {
189 	struct dw_i2c_dev *dev;
190 	struct i2c_adapter *adap;
191 	int r;
192 	struct dw_pci_controller *controller;
193 	struct dw_scl_sda_cfg *cfg;
194 
195 	if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
196 		dev_err(&pdev->dev, "%s: invalid driver data %ld\n", __func__,
197 			id->driver_data);
198 		return -EINVAL;
199 	}
200 
201 	controller = &dw_pci_controllers[id->driver_data];
202 
203 	r = pcim_enable_device(pdev);
204 	if (r) {
205 		dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
206 			r);
207 		return r;
208 	}
209 
210 	pci_set_master(pdev);
211 
212 	r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
213 	if (r) {
214 		dev_err(&pdev->dev, "I/O memory remapping failed\n");
215 		return r;
216 	}
217 
218 	dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
219 	if (!dev)
220 		return -ENOMEM;
221 
222 	r = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
223 	if (r < 0)
224 		return r;
225 
226 	dev->get_clk_rate_khz = controller->get_clk_rate_khz;
227 	dev->timings.bus_freq_hz = I2C_MAX_FAST_MODE_FREQ;
228 	dev->base = pcim_iomap_table(pdev)[0];
229 	dev->dev = &pdev->dev;
230 	dev->irq = pci_irq_vector(pdev, 0);
231 	dev->flags |= controller->flags;
232 
233 	pci_set_drvdata(pdev, dev);
234 
235 	if (controller->setup) {
236 		r = controller->setup(pdev, controller);
237 		if (r) {
238 			pci_free_irq_vectors(pdev);
239 			return r;
240 		}
241 	}
242 
243 	i2c_dw_acpi_adjust_bus_speed(&pdev->dev);
244 
245 	if (has_acpi_companion(&pdev->dev))
246 		i2c_dw_acpi_configure(&pdev->dev);
247 
248 	r = i2c_dw_validate_speed(dev);
249 	if (r) {
250 		pci_free_irq_vectors(pdev);
251 		return r;
252 	}
253 
254 	i2c_dw_configure(dev);
255 
256 	if (controller->scl_sda_cfg) {
257 		cfg = controller->scl_sda_cfg;
258 		dev->ss_hcnt = cfg->ss_hcnt;
259 		dev->fs_hcnt = cfg->fs_hcnt;
260 		dev->ss_lcnt = cfg->ss_lcnt;
261 		dev->fs_lcnt = cfg->fs_lcnt;
262 		dev->sda_hold_time = cfg->sda_hold;
263 	}
264 
265 	adap = &dev->adapter;
266 	adap->owner = THIS_MODULE;
267 	adap->class = 0;
268 	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
269 	adap->nr = controller->bus_num;
270 
271 	r = i2c_dw_probe(dev);
272 	if (r) {
273 		pci_free_irq_vectors(pdev);
274 		return r;
275 	}
276 
277 	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
278 	pm_runtime_use_autosuspend(&pdev->dev);
279 	pm_runtime_put_autosuspend(&pdev->dev);
280 	pm_runtime_allow(&pdev->dev);
281 
282 	return 0;
283 }
284 
285 static void i2c_dw_pci_remove(struct pci_dev *pdev)
286 {
287 	struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
288 
289 	dev->disable(dev);
290 	pm_runtime_forbid(&pdev->dev);
291 	pm_runtime_get_noresume(&pdev->dev);
292 
293 	i2c_del_adapter(&dev->adapter);
294 	devm_free_irq(&pdev->dev, dev->irq, dev);
295 	pci_free_irq_vectors(pdev);
296 }
297 
298 /* work with hotplug and coldplug */
299 MODULE_ALIAS("i2c_designware-pci");
300 
301 static const struct pci_device_id i2_designware_pci_ids[] = {
302 	/* Medfield */
303 	{ PCI_VDEVICE(INTEL, 0x0817), medfield },
304 	{ PCI_VDEVICE(INTEL, 0x0818), medfield },
305 	{ PCI_VDEVICE(INTEL, 0x0819), medfield },
306 	{ PCI_VDEVICE(INTEL, 0x082C), medfield },
307 	{ PCI_VDEVICE(INTEL, 0x082D), medfield },
308 	{ PCI_VDEVICE(INTEL, 0x082E), medfield },
309 	/* Merrifield */
310 	{ PCI_VDEVICE(INTEL, 0x1195), merrifield },
311 	{ PCI_VDEVICE(INTEL, 0x1196), merrifield },
312 	/* Baytrail */
313 	{ PCI_VDEVICE(INTEL, 0x0F41), baytrail },
314 	{ PCI_VDEVICE(INTEL, 0x0F42), baytrail },
315 	{ PCI_VDEVICE(INTEL, 0x0F43), baytrail },
316 	{ PCI_VDEVICE(INTEL, 0x0F44), baytrail },
317 	{ PCI_VDEVICE(INTEL, 0x0F45), baytrail },
318 	{ PCI_VDEVICE(INTEL, 0x0F46), baytrail },
319 	{ PCI_VDEVICE(INTEL, 0x0F47), baytrail },
320 	/* Haswell */
321 	{ PCI_VDEVICE(INTEL, 0x9c61), haswell },
322 	{ PCI_VDEVICE(INTEL, 0x9c62), haswell },
323 	/* Braswell / Cherrytrail */
324 	{ PCI_VDEVICE(INTEL, 0x22C1), cherrytrail },
325 	{ PCI_VDEVICE(INTEL, 0x22C2), cherrytrail },
326 	{ PCI_VDEVICE(INTEL, 0x22C3), cherrytrail },
327 	{ PCI_VDEVICE(INTEL, 0x22C4), cherrytrail },
328 	{ PCI_VDEVICE(INTEL, 0x22C5), cherrytrail },
329 	{ PCI_VDEVICE(INTEL, 0x22C6), cherrytrail },
330 	{ PCI_VDEVICE(INTEL, 0x22C7), cherrytrail },
331 	/* Elkhart Lake (PSE I2C) */
332 	{ PCI_VDEVICE(INTEL, 0x4bb9), elkhartlake },
333 	{ PCI_VDEVICE(INTEL, 0x4bba), elkhartlake },
334 	{ PCI_VDEVICE(INTEL, 0x4bbb), elkhartlake },
335 	{ PCI_VDEVICE(INTEL, 0x4bbc), elkhartlake },
336 	{ PCI_VDEVICE(INTEL, 0x4bbd), elkhartlake },
337 	{ PCI_VDEVICE(INTEL, 0x4bbe), elkhartlake },
338 	{ PCI_VDEVICE(INTEL, 0x4bbf), elkhartlake },
339 	{ PCI_VDEVICE(INTEL, 0x4bc0), elkhartlake },
340 	{ 0,}
341 };
342 MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
343 
344 static struct pci_driver dw_i2c_driver = {
345 	.name		= DRIVER_NAME,
346 	.id_table	= i2_designware_pci_ids,
347 	.probe		= i2c_dw_pci_probe,
348 	.remove		= i2c_dw_pci_remove,
349 	.driver         = {
350 		.pm     = &i2c_dw_pm_ops,
351 	},
352 };
353 
354 module_pci_driver(dw_i2c_driver);
355 
356 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
357 MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
358 MODULE_LICENSE("GPL");
359