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 bus_cfg;
50 	u32 tx_fifo_depth;
51 	u32 rx_fifo_depth;
52 	u32 clk_khz;
53 	u32 functionality;
54 	u32 flags;
55 	struct dw_scl_sda_cfg *scl_sda_cfg;
56 	int (*setup)(struct pci_dev *pdev, struct dw_pci_controller *c);
57 };
58 
59 #define INTEL_MID_STD_CFG  (DW_IC_CON_MASTER |			\
60 				DW_IC_CON_SLAVE_DISABLE |	\
61 				DW_IC_CON_RESTART_EN)
62 
63 /* Merrifield HCNT/LCNT/SDA hold time */
64 static struct dw_scl_sda_cfg mrfld_config = {
65 	.ss_hcnt = 0x2f8,
66 	.fs_hcnt = 0x87,
67 	.ss_lcnt = 0x37b,
68 	.fs_lcnt = 0x10a,
69 };
70 
71 /* BayTrail HCNT/LCNT/SDA hold time */
72 static struct dw_scl_sda_cfg byt_config = {
73 	.ss_hcnt = 0x200,
74 	.fs_hcnt = 0x55,
75 	.ss_lcnt = 0x200,
76 	.fs_lcnt = 0x99,
77 	.sda_hold = 0x6,
78 };
79 
80 /* Haswell HCNT/LCNT/SDA hold time */
81 static struct dw_scl_sda_cfg hsw_config = {
82 	.ss_hcnt = 0x01b0,
83 	.fs_hcnt = 0x48,
84 	.ss_lcnt = 0x01fb,
85 	.fs_lcnt = 0xa0,
86 	.sda_hold = 0x9,
87 };
88 
89 static int mfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
90 {
91 	switch (pdev->device) {
92 	case 0x0817:
93 		c->bus_cfg &= ~DW_IC_CON_SPEED_MASK;
94 		c->bus_cfg |= DW_IC_CON_SPEED_STD;
95 		/* fall through */
96 	case 0x0818:
97 	case 0x0819:
98 		c->bus_num = pdev->device - 0x817 + 3;
99 		return 0;
100 	case 0x082C:
101 	case 0x082D:
102 	case 0x082E:
103 		c->bus_num = pdev->device - 0x82C + 0;
104 		return 0;
105 	}
106 	return -ENODEV;
107 }
108 
109 static int mrfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
110 {
111 	/*
112 	 * On Intel Merrifield the user visible i2c busses are enumerated
113 	 * [1..7]. So, we add 1 to shift the default range. Besides that the
114 	 * first PCI slot provides 4 functions, that's why we have to add 0 to
115 	 * the first slot and 4 to the next one.
116 	 */
117 	switch (PCI_SLOT(pdev->devfn)) {
118 	case 8:
119 		c->bus_num = PCI_FUNC(pdev->devfn) + 0 + 1;
120 		return 0;
121 	case 9:
122 		c->bus_num = PCI_FUNC(pdev->devfn) + 4 + 1;
123 		return 0;
124 	}
125 	return -ENODEV;
126 }
127 
128 static struct dw_pci_controller dw_pci_controllers[] = {
129 	[medfield] = {
130 		.bus_num = -1,
131 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
132 		.tx_fifo_depth = 32,
133 		.rx_fifo_depth = 32,
134 		.functionality = I2C_FUNC_10BIT_ADDR,
135 		.clk_khz      = 25000,
136 		.setup = mfld_setup,
137 	},
138 	[merrifield] = {
139 		.bus_num = -1,
140 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
141 		.tx_fifo_depth = 64,
142 		.rx_fifo_depth = 64,
143 		.functionality = I2C_FUNC_10BIT_ADDR,
144 		.scl_sda_cfg = &mrfld_config,
145 		.setup = mrfld_setup,
146 	},
147 	[baytrail] = {
148 		.bus_num = -1,
149 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
150 		.tx_fifo_depth = 32,
151 		.rx_fifo_depth = 32,
152 		.functionality = I2C_FUNC_10BIT_ADDR,
153 		.scl_sda_cfg = &byt_config,
154 	},
155 	[haswell] = {
156 		.bus_num = -1,
157 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
158 		.tx_fifo_depth = 32,
159 		.rx_fifo_depth = 32,
160 		.functionality = I2C_FUNC_10BIT_ADDR,
161 		.scl_sda_cfg = &hsw_config,
162 	},
163 	[cherrytrail] = {
164 		.bus_num = -1,
165 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
166 		.tx_fifo_depth = 32,
167 		.rx_fifo_depth = 32,
168 		.functionality = I2C_FUNC_10BIT_ADDR,
169 		.flags = MODEL_CHERRYTRAIL,
170 		.scl_sda_cfg = &byt_config,
171 	},
172 	[elkhartlake] = {
173 		.bus_num = -1,
174 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
175 		.tx_fifo_depth = 32,
176 		.rx_fifo_depth = 32,
177 		.functionality = I2C_FUNC_10BIT_ADDR,
178 		.clk_khz = 100000,
179 	},
180 };
181 
182 #ifdef CONFIG_PM
183 static int i2c_dw_pci_suspend(struct device *dev)
184 {
185 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
186 
187 	i_dev->suspended = true;
188 	i_dev->disable(i_dev);
189 
190 	return 0;
191 }
192 
193 static int i2c_dw_pci_resume(struct device *dev)
194 {
195 	struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
196 	int ret;
197 
198 	ret = i_dev->init(i_dev);
199 	i_dev->suspended = false;
200 
201 	return ret;
202 }
203 #endif
204 
205 static UNIVERSAL_DEV_PM_OPS(i2c_dw_pm_ops, i2c_dw_pci_suspend,
206 			    i2c_dw_pci_resume, NULL);
207 
208 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
209 {
210 	return dev->controller->clk_khz;
211 }
212 
213 static int i2c_dw_pci_probe(struct pci_dev *pdev,
214 			    const struct pci_device_id *id)
215 {
216 	struct dw_i2c_dev *dev;
217 	struct i2c_adapter *adap;
218 	int r;
219 	struct dw_pci_controller *controller;
220 	struct dw_scl_sda_cfg *cfg;
221 
222 	if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
223 		dev_err(&pdev->dev, "%s: invalid driver data %ld\n", __func__,
224 			id->driver_data);
225 		return -EINVAL;
226 	}
227 
228 	controller = &dw_pci_controllers[id->driver_data];
229 
230 	r = pcim_enable_device(pdev);
231 	if (r) {
232 		dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
233 			r);
234 		return r;
235 	}
236 
237 	pci_set_master(pdev);
238 
239 	r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
240 	if (r) {
241 		dev_err(&pdev->dev, "I/O memory remapping failed\n");
242 		return r;
243 	}
244 
245 	dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
246 	if (!dev)
247 		return -ENOMEM;
248 
249 	r = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
250 	if (r < 0)
251 		return r;
252 
253 	dev->clk = NULL;
254 	dev->controller = controller;
255 	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
256 	dev->base = pcim_iomap_table(pdev)[0];
257 	dev->dev = &pdev->dev;
258 	dev->irq = pci_irq_vector(pdev, 0);
259 	dev->flags |= controller->flags;
260 
261 	if (controller->setup) {
262 		r = controller->setup(pdev, controller);
263 		if (r) {
264 			pci_free_irq_vectors(pdev);
265 			return r;
266 		}
267 	}
268 
269 	dev->functionality = controller->functionality |
270 				DW_IC_DEFAULT_FUNCTIONALITY;
271 
272 	dev->master_cfg = controller->bus_cfg;
273 	if (controller->scl_sda_cfg) {
274 		cfg = controller->scl_sda_cfg;
275 		dev->ss_hcnt = cfg->ss_hcnt;
276 		dev->fs_hcnt = cfg->fs_hcnt;
277 		dev->ss_lcnt = cfg->ss_lcnt;
278 		dev->fs_lcnt = cfg->fs_lcnt;
279 		dev->sda_hold_time = cfg->sda_hold;
280 	}
281 
282 	pci_set_drvdata(pdev, dev);
283 
284 	dev->tx_fifo_depth = controller->tx_fifo_depth;
285 	dev->rx_fifo_depth = controller->rx_fifo_depth;
286 
287 	adap = &dev->adapter;
288 	adap->owner = THIS_MODULE;
289 	adap->class = 0;
290 	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
291 	adap->nr = controller->bus_num;
292 
293 	r = i2c_dw_probe(dev);
294 	if (r) {
295 		pci_free_irq_vectors(pdev);
296 		return r;
297 	}
298 
299 	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
300 	pm_runtime_use_autosuspend(&pdev->dev);
301 	pm_runtime_put_autosuspend(&pdev->dev);
302 	pm_runtime_allow(&pdev->dev);
303 
304 	return 0;
305 }
306 
307 static void i2c_dw_pci_remove(struct pci_dev *pdev)
308 {
309 	struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
310 
311 	dev->disable(dev);
312 	pm_runtime_forbid(&pdev->dev);
313 	pm_runtime_get_noresume(&pdev->dev);
314 
315 	i2c_del_adapter(&dev->adapter);
316 	pci_free_irq_vectors(pdev);
317 }
318 
319 /* work with hotplug and coldplug */
320 MODULE_ALIAS("i2c_designware-pci");
321 
322 static const struct pci_device_id i2_designware_pci_ids[] = {
323 	/* Medfield */
324 	{ PCI_VDEVICE(INTEL, 0x0817), medfield },
325 	{ PCI_VDEVICE(INTEL, 0x0818), medfield },
326 	{ PCI_VDEVICE(INTEL, 0x0819), medfield },
327 	{ PCI_VDEVICE(INTEL, 0x082C), medfield },
328 	{ PCI_VDEVICE(INTEL, 0x082D), medfield },
329 	{ PCI_VDEVICE(INTEL, 0x082E), medfield },
330 	/* Merrifield */
331 	{ PCI_VDEVICE(INTEL, 0x1195), merrifield },
332 	{ PCI_VDEVICE(INTEL, 0x1196), merrifield },
333 	/* Baytrail */
334 	{ PCI_VDEVICE(INTEL, 0x0F41), baytrail },
335 	{ PCI_VDEVICE(INTEL, 0x0F42), baytrail },
336 	{ PCI_VDEVICE(INTEL, 0x0F43), baytrail },
337 	{ PCI_VDEVICE(INTEL, 0x0F44), baytrail },
338 	{ PCI_VDEVICE(INTEL, 0x0F45), baytrail },
339 	{ PCI_VDEVICE(INTEL, 0x0F46), baytrail },
340 	{ PCI_VDEVICE(INTEL, 0x0F47), baytrail },
341 	/* Haswell */
342 	{ PCI_VDEVICE(INTEL, 0x9c61), haswell },
343 	{ PCI_VDEVICE(INTEL, 0x9c62), haswell },
344 	/* Braswell / Cherrytrail */
345 	{ PCI_VDEVICE(INTEL, 0x22C1), cherrytrail },
346 	{ PCI_VDEVICE(INTEL, 0x22C2), cherrytrail },
347 	{ PCI_VDEVICE(INTEL, 0x22C3), cherrytrail },
348 	{ PCI_VDEVICE(INTEL, 0x22C4), cherrytrail },
349 	{ PCI_VDEVICE(INTEL, 0x22C5), cherrytrail },
350 	{ PCI_VDEVICE(INTEL, 0x22C6), cherrytrail },
351 	{ PCI_VDEVICE(INTEL, 0x22C7), cherrytrail },
352 	/* Elkhart Lake (PSE I2C) */
353 	{ PCI_VDEVICE(INTEL, 0x4bb9), elkhartlake },
354 	{ PCI_VDEVICE(INTEL, 0x4bba), elkhartlake },
355 	{ PCI_VDEVICE(INTEL, 0x4bbb), elkhartlake },
356 	{ PCI_VDEVICE(INTEL, 0x4bbc), elkhartlake },
357 	{ PCI_VDEVICE(INTEL, 0x4bbd), elkhartlake },
358 	{ PCI_VDEVICE(INTEL, 0x4bbe), elkhartlake },
359 	{ PCI_VDEVICE(INTEL, 0x4bbf), elkhartlake },
360 	{ PCI_VDEVICE(INTEL, 0x4bc0), elkhartlake },
361 	{ 0,}
362 };
363 MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
364 
365 static struct pci_driver dw_i2c_driver = {
366 	.name		= DRIVER_NAME,
367 	.id_table	= i2_designware_pci_ids,
368 	.probe		= i2c_dw_pci_probe,
369 	.remove		= i2c_dw_pci_remove,
370 	.driver         = {
371 		.pm     = &i2c_dw_pm_ops,
372 	},
373 };
374 
375 module_pci_driver(dw_i2c_driver);
376 
377 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
378 MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
379 MODULE_LICENSE("GPL");
380