1 /*
2  * Synopsys DesignWare I2C adapter driver (master only).
3  *
4  * Based on the TI DAVINCI I2C adapter driver.
5  *
6  * Copyright (C) 2006 Texas Instruments.
7  * Copyright (C) 2007 MontaVista Software Inc.
8  * Copyright (C) 2009 Provigent Ltd.
9  * Copyright (C) 2011, 2015, 2016 Intel Corporation.
10  *
11  * ----------------------------------------------------------------------------
12  *
13  * This program is free software; you can redistribute it and/or modify
14  * it under the terms of the GNU General Public License as published by
15  * the Free Software Foundation; either version 2 of the License, or
16  * (at your option) any later version.
17  *
18  * This program is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
21  * GNU General Public License for more details.
22  * ----------------------------------------------------------------------------
23  *
24  */
25 
26 #include <linux/acpi.h>
27 #include <linux/delay.h>
28 #include <linux/err.h>
29 #include <linux/errno.h>
30 #include <linux/i2c.h>
31 #include <linux/interrupt.h>
32 #include <linux/io.h>
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/pci.h>
36 #include <linux/pm_runtime.h>
37 #include <linux/sched.h>
38 #include <linux/slab.h>
39 
40 #include "i2c-designware-core.h"
41 
42 #define DRIVER_NAME "i2c-designware-pci"
43 
44 enum dw_pci_ctl_id_t {
45 	medfield,
46 	merrifield,
47 	baytrail,
48 	haswell,
49 };
50 
51 struct dw_scl_sda_cfg {
52 	u32 ss_hcnt;
53 	u32 fs_hcnt;
54 	u32 ss_lcnt;
55 	u32 fs_lcnt;
56 	u32 sda_hold;
57 };
58 
59 struct dw_pci_controller {
60 	u32 bus_num;
61 	u32 bus_cfg;
62 	u32 tx_fifo_depth;
63 	u32 rx_fifo_depth;
64 	u32 clk_khz;
65 	u32 functionality;
66 	struct dw_scl_sda_cfg *scl_sda_cfg;
67 	int (*setup)(struct pci_dev *pdev, struct dw_pci_controller *c);
68 };
69 
70 #define INTEL_MID_STD_CFG  (DW_IC_CON_MASTER |			\
71 				DW_IC_CON_SLAVE_DISABLE |	\
72 				DW_IC_CON_RESTART_EN)
73 
74 #define DW_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C |			\
75 					I2C_FUNC_SMBUS_BYTE |		\
76 					I2C_FUNC_SMBUS_BYTE_DATA |	\
77 					I2C_FUNC_SMBUS_WORD_DATA |	\
78 					I2C_FUNC_SMBUS_I2C_BLOCK)
79 
80 /* Merrifield HCNT/LCNT/SDA hold time */
81 static struct dw_scl_sda_cfg mrfld_config = {
82 	.ss_hcnt = 0x2f8,
83 	.fs_hcnt = 0x87,
84 	.ss_lcnt = 0x37b,
85 	.fs_lcnt = 0x10a,
86 };
87 
88 /* BayTrail HCNT/LCNT/SDA hold time */
89 static struct dw_scl_sda_cfg byt_config = {
90 	.ss_hcnt = 0x200,
91 	.fs_hcnt = 0x55,
92 	.ss_lcnt = 0x200,
93 	.fs_lcnt = 0x99,
94 	.sda_hold = 0x6,
95 };
96 
97 /* Haswell HCNT/LCNT/SDA hold time */
98 static struct dw_scl_sda_cfg hsw_config = {
99 	.ss_hcnt = 0x01b0,
100 	.fs_hcnt = 0x48,
101 	.ss_lcnt = 0x01fb,
102 	.fs_lcnt = 0xa0,
103 	.sda_hold = 0x9,
104 };
105 
106 static int mfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
107 {
108 	switch (pdev->device) {
109 	case 0x0817:
110 		c->bus_cfg &= ~DW_IC_CON_SPEED_MASK;
111 		c->bus_cfg |= DW_IC_CON_SPEED_STD;
112 	case 0x0818:
113 	case 0x0819:
114 		c->bus_num = pdev->device - 0x817 + 3;
115 		return 0;
116 	case 0x082C:
117 	case 0x082D:
118 	case 0x082E:
119 		c->bus_num = pdev->device - 0x82C + 0;
120 		return 0;
121 	}
122 	return -ENODEV;
123 }
124 
125 static int mrfld_setup(struct pci_dev *pdev, struct dw_pci_controller *c)
126 {
127 	/*
128 	 * On Intel Merrifield the user visible i2c busses are enumerated
129 	 * [1..7]. So, we add 1 to shift the default range. Besides that the
130 	 * first PCI slot provides 4 functions, that's why we have to add 0 to
131 	 * the first slot and 4 to the next one.
132 	 */
133 	switch (PCI_SLOT(pdev->devfn)) {
134 	case 8:
135 		c->bus_num = PCI_FUNC(pdev->devfn) + 0 + 1;
136 		return 0;
137 	case 9:
138 		c->bus_num = PCI_FUNC(pdev->devfn) + 4 + 1;
139 		return 0;
140 	}
141 	return -ENODEV;
142 }
143 
144 static struct dw_pci_controller dw_pci_controllers[] = {
145 	[medfield] = {
146 		.bus_num = -1,
147 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
148 		.tx_fifo_depth = 32,
149 		.rx_fifo_depth = 32,
150 		.clk_khz      = 25000,
151 		.setup = mfld_setup,
152 	},
153 	[merrifield] = {
154 		.bus_num = -1,
155 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
156 		.tx_fifo_depth = 64,
157 		.rx_fifo_depth = 64,
158 		.scl_sda_cfg = &mrfld_config,
159 		.setup = mrfld_setup,
160 	},
161 	[baytrail] = {
162 		.bus_num = -1,
163 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
164 		.tx_fifo_depth = 32,
165 		.rx_fifo_depth = 32,
166 		.functionality = I2C_FUNC_10BIT_ADDR,
167 		.scl_sda_cfg = &byt_config,
168 	},
169 	[haswell] = {
170 		.bus_num = -1,
171 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
172 		.tx_fifo_depth = 32,
173 		.rx_fifo_depth = 32,
174 		.functionality = I2C_FUNC_10BIT_ADDR,
175 		.scl_sda_cfg = &hsw_config,
176 	},
177 };
178 
179 #ifdef CONFIG_PM
180 static int i2c_dw_pci_suspend(struct device *dev)
181 {
182 	struct pci_dev *pdev = to_pci_dev(dev);
183 
184 	i2c_dw_disable(pci_get_drvdata(pdev));
185 	return 0;
186 }
187 
188 static int i2c_dw_pci_resume(struct device *dev)
189 {
190 	struct pci_dev *pdev = to_pci_dev(dev);
191 
192 	return i2c_dw_init(pci_get_drvdata(pdev));
193 }
194 #endif
195 
196 static UNIVERSAL_DEV_PM_OPS(i2c_dw_pm_ops, i2c_dw_pci_suspend,
197 			    i2c_dw_pci_resume, NULL);
198 
199 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
200 {
201 	return dev->controller->clk_khz;
202 }
203 
204 static int i2c_dw_pci_probe(struct pci_dev *pdev,
205 			    const struct pci_device_id *id)
206 {
207 	struct dw_i2c_dev *dev;
208 	struct i2c_adapter *adap;
209 	int r;
210 	struct dw_pci_controller *controller;
211 	struct dw_scl_sda_cfg *cfg;
212 
213 	if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
214 		dev_err(&pdev->dev, "%s: invalid driver data %ld\n", __func__,
215 			id->driver_data);
216 		return -EINVAL;
217 	}
218 
219 	controller = &dw_pci_controllers[id->driver_data];
220 
221 	r = pcim_enable_device(pdev);
222 	if (r) {
223 		dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
224 			r);
225 		return r;
226 	}
227 
228 	r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
229 	if (r) {
230 		dev_err(&pdev->dev, "I/O memory remapping failed\n");
231 		return r;
232 	}
233 
234 	dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
235 	if (!dev)
236 		return -ENOMEM;
237 
238 	dev->clk = NULL;
239 	dev->controller = controller;
240 	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
241 	dev->base = pcim_iomap_table(pdev)[0];
242 	dev->dev = &pdev->dev;
243 	dev->irq = pdev->irq;
244 
245 	if (controller->setup) {
246 		r = controller->setup(pdev, controller);
247 		if (r)
248 			return r;
249 	}
250 
251 	dev->functionality = controller->functionality |
252 				DW_DEFAULT_FUNCTIONALITY;
253 
254 	dev->master_cfg = controller->bus_cfg;
255 	if (controller->scl_sda_cfg) {
256 		cfg = controller->scl_sda_cfg;
257 		dev->ss_hcnt = cfg->ss_hcnt;
258 		dev->fs_hcnt = cfg->fs_hcnt;
259 		dev->ss_lcnt = cfg->ss_lcnt;
260 		dev->fs_lcnt = cfg->fs_lcnt;
261 		dev->sda_hold_time = cfg->sda_hold;
262 	}
263 
264 	pci_set_drvdata(pdev, dev);
265 
266 	dev->tx_fifo_depth = controller->tx_fifo_depth;
267 	dev->rx_fifo_depth = controller->rx_fifo_depth;
268 
269 	adap = &dev->adapter;
270 	adap->owner = THIS_MODULE;
271 	adap->class = 0;
272 	ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
273 	adap->nr = controller->bus_num;
274 
275 	r = i2c_dw_probe(dev);
276 	if (r)
277 		return r;
278 
279 	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
280 	pm_runtime_use_autosuspend(&pdev->dev);
281 	pm_runtime_put_autosuspend(&pdev->dev);
282 	pm_runtime_allow(&pdev->dev);
283 
284 	return 0;
285 }
286 
287 static void i2c_dw_pci_remove(struct pci_dev *pdev)
288 {
289 	struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
290 
291 	i2c_dw_disable(dev);
292 	pm_runtime_forbid(&pdev->dev);
293 	pm_runtime_get_noresume(&pdev->dev);
294 
295 	i2c_del_adapter(&dev->adapter);
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), baytrail },
325 	{ PCI_VDEVICE(INTEL, 0x22C2), baytrail },
326 	{ PCI_VDEVICE(INTEL, 0x22C3), baytrail },
327 	{ PCI_VDEVICE(INTEL, 0x22C4), baytrail },
328 	{ PCI_VDEVICE(INTEL, 0x22C5), baytrail },
329 	{ PCI_VDEVICE(INTEL, 0x22C6), baytrail },
330 	{ PCI_VDEVICE(INTEL, 0x22C7), baytrail },
331 	{ 0,}
332 };
333 MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
334 
335 static struct pci_driver dw_i2c_driver = {
336 	.name		= DRIVER_NAME,
337 	.id_table	= i2_designware_pci_ids,
338 	.probe		= i2c_dw_pci_probe,
339 	.remove		= i2c_dw_pci_remove,
340 	.driver         = {
341 		.pm     = &i2c_dw_pm_ops,
342 	},
343 };
344 
345 module_pci_driver(dw_i2c_driver);
346 
347 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
348 MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
349 MODULE_LICENSE("GPL");
350