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 };
37 
38 struct dw_scl_sda_cfg {
39 	u32 ss_hcnt;
40 	u32 fs_hcnt;
41 	u32 ss_lcnt;
42 	u32 fs_lcnt;
43 	u32 sda_hold;
44 };
45 
46 struct dw_pci_controller {
47 	u32 bus_num;
48 	u32 bus_cfg;
49 	u32 tx_fifo_depth;
50 	u32 rx_fifo_depth;
51 	u32 clk_khz;
52 	u32 functionality;
53 	u32 flags;
54 	struct dw_scl_sda_cfg *scl_sda_cfg;
55 	int (*setup)(struct pci_dev *pdev, struct dw_pci_controller *c);
56 };
57 
58 #define INTEL_MID_STD_CFG  (DW_IC_CON_MASTER |			\
59 				DW_IC_CON_SLAVE_DISABLE |	\
60 				DW_IC_CON_RESTART_EN)
61 
62 /* Merrifield HCNT/LCNT/SDA hold time */
63 static struct dw_scl_sda_cfg mrfld_config = {
64 	.ss_hcnt = 0x2f8,
65 	.fs_hcnt = 0x87,
66 	.ss_lcnt = 0x37b,
67 	.fs_lcnt = 0x10a,
68 };
69 
70 /* BayTrail HCNT/LCNT/SDA hold time */
71 static struct dw_scl_sda_cfg byt_config = {
72 	.ss_hcnt = 0x200,
73 	.fs_hcnt = 0x55,
74 	.ss_lcnt = 0x200,
75 	.fs_lcnt = 0x99,
76 	.sda_hold = 0x6,
77 };
78 
79 /* Haswell HCNT/LCNT/SDA hold time */
80 static struct dw_scl_sda_cfg hsw_config = {
81 	.ss_hcnt = 0x01b0,
82 	.fs_hcnt = 0x48,
83 	.ss_lcnt = 0x01fb,
84 	.fs_lcnt = 0xa0,
85 	.sda_hold = 0x9,
86 };
87 
88 static int mfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
89 {
90 	switch (pdev->device) {
91 	case 0x0817:
92 		c->bus_cfg &= ~DW_IC_CON_SPEED_MASK;
93 		c->bus_cfg |= DW_IC_CON_SPEED_STD;
94 		/* fall through */
95 	case 0x0818:
96 	case 0x0819:
97 		c->bus_num = pdev->device - 0x817 + 3;
98 		return 0;
99 	case 0x082C:
100 	case 0x082D:
101 	case 0x082E:
102 		c->bus_num = pdev->device - 0x82C + 0;
103 		return 0;
104 	}
105 	return -ENODEV;
106 }
107 
108 static int mrfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
109 {
110 	/*
111 	 * On Intel Merrifield the user visible i2c busses are enumerated
112 	 * [1..7]. So, we add 1 to shift the default range. Besides that the
113 	 * first PCI slot provides 4 functions, that's why we have to add 0 to
114 	 * the first slot and 4 to the next one.
115 	 */
116 	switch (PCI_SLOT(pdev->devfn)) {
117 	case 8:
118 		c->bus_num = PCI_FUNC(pdev->devfn) + 0 + 1;
119 		return 0;
120 	case 9:
121 		c->bus_num = PCI_FUNC(pdev->devfn) + 4 + 1;
122 		return 0;
123 	}
124 	return -ENODEV;
125 }
126 
127 static struct dw_pci_controller dw_pci_controllers[] = {
128 	[medfield] = {
129 		.bus_num = -1,
130 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
131 		.tx_fifo_depth = 32,
132 		.rx_fifo_depth = 32,
133 		.functionality = I2C_FUNC_10BIT_ADDR,
134 		.clk_khz      = 25000,
135 		.setup = mfld_setup,
136 	},
137 	[merrifield] = {
138 		.bus_num = -1,
139 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
140 		.tx_fifo_depth = 64,
141 		.rx_fifo_depth = 64,
142 		.functionality = I2C_FUNC_10BIT_ADDR,
143 		.scl_sda_cfg = &mrfld_config,
144 		.setup = mrfld_setup,
145 	},
146 	[baytrail] = {
147 		.bus_num = -1,
148 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
149 		.tx_fifo_depth = 32,
150 		.rx_fifo_depth = 32,
151 		.functionality = I2C_FUNC_10BIT_ADDR,
152 		.scl_sda_cfg = &byt_config,
153 	},
154 	[haswell] = {
155 		.bus_num = -1,
156 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
157 		.tx_fifo_depth = 32,
158 		.rx_fifo_depth = 32,
159 		.functionality = I2C_FUNC_10BIT_ADDR,
160 		.scl_sda_cfg = &hsw_config,
161 	},
162 	[cherrytrail] = {
163 		.bus_num = -1,
164 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
165 		.tx_fifo_depth = 32,
166 		.rx_fifo_depth = 32,
167 		.functionality = I2C_FUNC_10BIT_ADDR,
168 		.flags = MODEL_CHERRYTRAIL,
169 		.scl_sda_cfg = &byt_config,
170 	},
171 };
172 
173 #ifdef CONFIG_PM
174 static int i2c_dw_pci_suspend(struct device *dev)
175 {
176 	struct pci_dev *pdev = to_pci_dev(dev);
177 	struct dw_i2c_dev *i_dev = pci_get_drvdata(pdev);
178 
179 	i_dev->suspended = true;
180 	i_dev->disable(i_dev);
181 
182 	return 0;
183 }
184 
185 static int i2c_dw_pci_resume(struct device *dev)
186 {
187 	struct pci_dev *pdev = to_pci_dev(dev);
188 	struct dw_i2c_dev *i_dev = pci_get_drvdata(pdev);
189 	int ret;
190 
191 	ret = i_dev->init(i_dev);
192 	i_dev->suspended = false;
193 
194 	return ret;
195 }
196 #endif
197 
198 static UNIVERSAL_DEV_PM_OPS(i2c_dw_pm_ops, i2c_dw_pci_suspend,
199 			    i2c_dw_pci_resume, NULL);
200 
201 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
202 {
203 	return dev->controller->clk_khz;
204 }
205 
206 static int i2c_dw_pci_probe(struct pci_dev *pdev,
207 			    const struct pci_device_id *id)
208 {
209 	struct dw_i2c_dev *dev;
210 	struct i2c_adapter *adap;
211 	int r;
212 	struct dw_pci_controller *controller;
213 	struct dw_scl_sda_cfg *cfg;
214 
215 	if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
216 		dev_err(&pdev->dev, "%s: invalid driver data %ld\n", __func__,
217 			id->driver_data);
218 		return -EINVAL;
219 	}
220 
221 	controller = &dw_pci_controllers[id->driver_data];
222 
223 	r = pcim_enable_device(pdev);
224 	if (r) {
225 		dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
226 			r);
227 		return r;
228 	}
229 
230 	r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
231 	if (r) {
232 		dev_err(&pdev->dev, "I/O memory remapping failed\n");
233 		return r;
234 	}
235 
236 	dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
237 	if (!dev)
238 		return -ENOMEM;
239 
240 	dev->clk = NULL;
241 	dev->controller = controller;
242 	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
243 	dev->base = pcim_iomap_table(pdev)[0];
244 	dev->dev = &pdev->dev;
245 	dev->irq = pdev->irq;
246 	dev->flags |= controller->flags;
247 
248 	if (controller->setup) {
249 		r = controller->setup(pdev, controller);
250 		if (r)
251 			return r;
252 	}
253 
254 	dev->functionality = controller->functionality |
255 				DW_IC_DEFAULT_FUNCTIONALITY;
256 
257 	dev->master_cfg = controller->bus_cfg;
258 	if (controller->scl_sda_cfg) {
259 		cfg = controller->scl_sda_cfg;
260 		dev->ss_hcnt = cfg->ss_hcnt;
261 		dev->fs_hcnt = cfg->fs_hcnt;
262 		dev->ss_lcnt = cfg->ss_lcnt;
263 		dev->fs_lcnt = cfg->fs_lcnt;
264 		dev->sda_hold_time = cfg->sda_hold;
265 	}
266 
267 	pci_set_drvdata(pdev, dev);
268 
269 	dev->tx_fifo_depth = controller->tx_fifo_depth;
270 	dev->rx_fifo_depth = controller->rx_fifo_depth;
271 
272 	adap = &dev->adapter;
273 	adap->owner = THIS_MODULE;
274 	adap->class = 0;
275 	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
276 	adap->nr = controller->bus_num;
277 
278 	r = i2c_dw_probe(dev);
279 	if (r)
280 		return r;
281 
282 	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
283 	pm_runtime_use_autosuspend(&pdev->dev);
284 	pm_runtime_put_autosuspend(&pdev->dev);
285 	pm_runtime_allow(&pdev->dev);
286 
287 	return 0;
288 }
289 
290 static void i2c_dw_pci_remove(struct pci_dev *pdev)
291 {
292 	struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
293 
294 	dev->disable(dev);
295 	pm_runtime_forbid(&pdev->dev);
296 	pm_runtime_get_noresume(&pdev->dev);
297 
298 	i2c_del_adapter(&dev->adapter);
299 }
300 
301 /* work with hotplug and coldplug */
302 MODULE_ALIAS("i2c_designware-pci");
303 
304 static const struct pci_device_id i2_designware_pci_ids[] = {
305 	/* Medfield */
306 	{ PCI_VDEVICE(INTEL, 0x0817), medfield },
307 	{ PCI_VDEVICE(INTEL, 0x0818), medfield },
308 	{ PCI_VDEVICE(INTEL, 0x0819), medfield },
309 	{ PCI_VDEVICE(INTEL, 0x082C), medfield },
310 	{ PCI_VDEVICE(INTEL, 0x082D), medfield },
311 	{ PCI_VDEVICE(INTEL, 0x082E), medfield },
312 	/* Merrifield */
313 	{ PCI_VDEVICE(INTEL, 0x1195), merrifield },
314 	{ PCI_VDEVICE(INTEL, 0x1196), merrifield },
315 	/* Baytrail */
316 	{ PCI_VDEVICE(INTEL, 0x0F41), baytrail },
317 	{ PCI_VDEVICE(INTEL, 0x0F42), baytrail },
318 	{ PCI_VDEVICE(INTEL, 0x0F43), baytrail },
319 	{ PCI_VDEVICE(INTEL, 0x0F44), baytrail },
320 	{ PCI_VDEVICE(INTEL, 0x0F45), baytrail },
321 	{ PCI_VDEVICE(INTEL, 0x0F46), baytrail },
322 	{ PCI_VDEVICE(INTEL, 0x0F47), baytrail },
323 	/* Haswell */
324 	{ PCI_VDEVICE(INTEL, 0x9c61), haswell },
325 	{ PCI_VDEVICE(INTEL, 0x9c62), haswell },
326 	/* Braswell / Cherrytrail */
327 	{ PCI_VDEVICE(INTEL, 0x22C1), cherrytrail },
328 	{ PCI_VDEVICE(INTEL, 0x22C2), cherrytrail },
329 	{ PCI_VDEVICE(INTEL, 0x22C3), cherrytrail },
330 	{ PCI_VDEVICE(INTEL, 0x22C4), cherrytrail },
331 	{ PCI_VDEVICE(INTEL, 0x22C5), cherrytrail },
332 	{ PCI_VDEVICE(INTEL, 0x22C6), cherrytrail },
333 	{ PCI_VDEVICE(INTEL, 0x22C7), cherrytrail },
334 	{ 0,}
335 };
336 MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
337 
338 static struct pci_driver dw_i2c_driver = {
339 	.name		= DRIVER_NAME,
340 	.id_table	= i2_designware_pci_ids,
341 	.probe		= i2c_dw_pci_probe,
342 	.remove		= i2c_dw_pci_remove,
343 	.driver         = {
344 		.pm     = &i2c_dw_pm_ops,
345 	},
346 };
347 
348 module_pci_driver(dw_i2c_driver);
349 
350 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
351 MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
352 MODULE_LICENSE("GPL");
353