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 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/kernel.h>
27 #include <linux/module.h>
28 #include <linux/delay.h>
29 #include <linux/i2c.h>
30 #include <linux/errno.h>
31 #include <linux/sched.h>
32 #include <linux/err.h>
33 #include <linux/interrupt.h>
34 #include <linux/io.h>
35 #include <linux/slab.h>
36 #include <linux/pci.h>
37 #include <linux/pm_runtime.h>
38 #include "i2c-designware-core.h"
39 
40 #define DRIVER_NAME "i2c-designware-pci"
41 
42 enum dw_pci_ctl_id_t {
43 	medfield_0,
44 	medfield_1,
45 	medfield_2,
46 	medfield_3,
47 	medfield_4,
48 	medfield_5,
49 
50 	baytrail,
51 	haswell,
52 };
53 
54 struct dw_scl_sda_cfg {
55 	u32 ss_hcnt;
56 	u32 fs_hcnt;
57 	u32 ss_lcnt;
58 	u32 fs_lcnt;
59 	u32 sda_hold;
60 };
61 
62 struct dw_pci_controller {
63 	u32 bus_num;
64 	u32 bus_cfg;
65 	u32 tx_fifo_depth;
66 	u32 rx_fifo_depth;
67 	u32 clk_khz;
68 	u32 functionality;
69 	struct dw_scl_sda_cfg *scl_sda_cfg;
70 };
71 
72 #define INTEL_MID_STD_CFG  (DW_IC_CON_MASTER |			\
73 				DW_IC_CON_SLAVE_DISABLE |	\
74 				DW_IC_CON_RESTART_EN)
75 
76 #define DW_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C |			\
77 					I2C_FUNC_SMBUS_BYTE |		\
78 					I2C_FUNC_SMBUS_BYTE_DATA |	\
79 					I2C_FUNC_SMBUS_WORD_DATA |	\
80 					I2C_FUNC_SMBUS_I2C_BLOCK)
81 
82 /* BayTrail HCNT/LCNT/SDA hold time */
83 static struct dw_scl_sda_cfg byt_config = {
84 	.ss_hcnt = 0x200,
85 	.fs_hcnt = 0x55,
86 	.ss_lcnt = 0x200,
87 	.fs_lcnt = 0x99,
88 	.sda_hold = 0x6,
89 };
90 
91 /* Haswell HCNT/LCNT/SDA hold time */
92 static struct dw_scl_sda_cfg hsw_config = {
93 	.ss_hcnt = 0x01b0,
94 	.fs_hcnt = 0x48,
95 	.ss_lcnt = 0x01fb,
96 	.fs_lcnt = 0xa0,
97 	.sda_hold = 0x9,
98 };
99 
100 static struct dw_pci_controller dw_pci_controllers[] = {
101 	[medfield_0] = {
102 		.bus_num     = 0,
103 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
104 		.tx_fifo_depth = 32,
105 		.rx_fifo_depth = 32,
106 		.clk_khz      = 25000,
107 	},
108 	[medfield_1] = {
109 		.bus_num     = 1,
110 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
111 		.tx_fifo_depth = 32,
112 		.rx_fifo_depth = 32,
113 		.clk_khz      = 25000,
114 	},
115 	[medfield_2] = {
116 		.bus_num     = 2,
117 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
118 		.tx_fifo_depth = 32,
119 		.rx_fifo_depth = 32,
120 		.clk_khz      = 25000,
121 	},
122 	[medfield_3] = {
123 		.bus_num     = 3,
124 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_STD,
125 		.tx_fifo_depth = 32,
126 		.rx_fifo_depth = 32,
127 		.clk_khz      = 25000,
128 	},
129 	[medfield_4] = {
130 		.bus_num     = 4,
131 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
132 		.tx_fifo_depth = 32,
133 		.rx_fifo_depth = 32,
134 		.clk_khz      = 25000,
135 	},
136 	[medfield_5] = {
137 		.bus_num     = 5,
138 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
139 		.tx_fifo_depth = 32,
140 		.rx_fifo_depth = 32,
141 		.clk_khz      = 25000,
142 	},
143 	[baytrail] = {
144 		.bus_num = -1,
145 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
146 		.tx_fifo_depth = 32,
147 		.rx_fifo_depth = 32,
148 		.functionality = I2C_FUNC_10BIT_ADDR,
149 		.scl_sda_cfg = &byt_config,
150 	},
151 	[haswell] = {
152 		.bus_num = -1,
153 		.bus_cfg = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
154 		.tx_fifo_depth = 32,
155 		.rx_fifo_depth = 32,
156 		.functionality = I2C_FUNC_10BIT_ADDR,
157 		.scl_sda_cfg = &hsw_config,
158 	},
159 };
160 
161 static struct i2c_algorithm i2c_dw_algo = {
162 	.master_xfer	= i2c_dw_xfer,
163 	.functionality	= i2c_dw_func,
164 };
165 
166 #ifdef CONFIG_PM
167 static int i2c_dw_pci_suspend(struct device *dev)
168 {
169 	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
170 
171 	i2c_dw_disable(pci_get_drvdata(pdev));
172 	return 0;
173 }
174 
175 static int i2c_dw_pci_resume(struct device *dev)
176 {
177 	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
178 
179 	return i2c_dw_init(pci_get_drvdata(pdev));
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 u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
187 {
188 	return dev->controller->clk_khz;
189 }
190 
191 static int i2c_dw_pci_probe(struct pci_dev *pdev,
192 			    const struct pci_device_id *id)
193 {
194 	struct dw_i2c_dev *dev;
195 	struct i2c_adapter *adap;
196 	int r;
197 	struct  dw_pci_controller *controller;
198 	struct dw_scl_sda_cfg *cfg;
199 
200 	if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
201 		dev_err(&pdev->dev, "%s: invalid driver data %ld\n", __func__,
202 			id->driver_data);
203 		return -EINVAL;
204 	}
205 
206 	controller = &dw_pci_controllers[id->driver_data];
207 
208 	r = pcim_enable_device(pdev);
209 	if (r) {
210 		dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
211 			r);
212 		return r;
213 	}
214 
215 	r = pcim_iomap_regions(pdev, 1 << 0, pci_name(pdev));
216 	if (r) {
217 		dev_err(&pdev->dev, "I/O memory remapping failed\n");
218 		return r;
219 	}
220 
221 	dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
222 	if (!dev)
223 		return -ENOMEM;
224 
225 	init_completion(&dev->cmd_complete);
226 	mutex_init(&dev->lock);
227 	dev->clk = NULL;
228 	dev->controller = controller;
229 	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
230 	dev->base = pcim_iomap_table(pdev)[0];
231 	dev->dev = &pdev->dev;
232 	dev->functionality = controller->functionality |
233 				DW_DEFAULT_FUNCTIONALITY;
234 
235 	dev->master_cfg = controller->bus_cfg;
236 	if (controller->scl_sda_cfg) {
237 		cfg = controller->scl_sda_cfg;
238 		dev->ss_hcnt = cfg->ss_hcnt;
239 		dev->fs_hcnt = cfg->fs_hcnt;
240 		dev->ss_lcnt = cfg->ss_lcnt;
241 		dev->fs_lcnt = cfg->fs_lcnt;
242 		dev->sda_hold_time = cfg->sda_hold;
243 	}
244 
245 	pci_set_drvdata(pdev, dev);
246 
247 	dev->tx_fifo_depth = controller->tx_fifo_depth;
248 	dev->rx_fifo_depth = controller->rx_fifo_depth;
249 	r = i2c_dw_init(dev);
250 	if (r)
251 		return r;
252 
253 	adap = &dev->adapter;
254 	i2c_set_adapdata(adap, dev);
255 	adap->owner = THIS_MODULE;
256 	adap->class = 0;
257 	adap->algo = &i2c_dw_algo;
258 	adap->dev.parent = &pdev->dev;
259 	adap->nr = controller->bus_num;
260 
261 	snprintf(adap->name, sizeof(adap->name), "i2c-designware-pci");
262 
263 	r = devm_request_irq(&pdev->dev, pdev->irq, i2c_dw_isr, IRQF_SHARED,
264 			adap->name, dev);
265 	if (r) {
266 		dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
267 		return r;
268 	}
269 
270 	i2c_dw_disable_int(dev);
271 	i2c_dw_clear_int(dev);
272 	r = i2c_add_numbered_adapter(adap);
273 	if (r) {
274 		dev_err(&pdev->dev, "failure adding adapter\n");
275 		return r;
276 	}
277 
278 	pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
279 	pm_runtime_use_autosuspend(&pdev->dev);
280 	pm_runtime_put_autosuspend(&pdev->dev);
281 	pm_runtime_allow(&pdev->dev);
282 
283 	return 0;
284 }
285 
286 static void i2c_dw_pci_remove(struct pci_dev *pdev)
287 {
288 	struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
289 
290 	i2c_dw_disable(dev);
291 	pm_runtime_forbid(&pdev->dev);
292 	pm_runtime_get_noresume(&pdev->dev);
293 
294 	i2c_del_adapter(&dev->adapter);
295 }
296 
297 /* work with hotplug and coldplug */
298 MODULE_ALIAS("i2c_designware-pci");
299 
300 static const struct pci_device_id i2_designware_pci_ids[] = {
301 	/* Medfield */
302 	{ PCI_VDEVICE(INTEL, 0x0817), medfield_3 },
303 	{ PCI_VDEVICE(INTEL, 0x0818), medfield_4 },
304 	{ PCI_VDEVICE(INTEL, 0x0819), medfield_5 },
305 	{ PCI_VDEVICE(INTEL, 0x082C), medfield_0 },
306 	{ PCI_VDEVICE(INTEL, 0x082D), medfield_1 },
307 	{ PCI_VDEVICE(INTEL, 0x082E), medfield_2 },
308 	/* Baytrail */
309 	{ PCI_VDEVICE(INTEL, 0x0F41), baytrail },
310 	{ PCI_VDEVICE(INTEL, 0x0F42), baytrail },
311 	{ PCI_VDEVICE(INTEL, 0x0F43), baytrail },
312 	{ PCI_VDEVICE(INTEL, 0x0F44), baytrail },
313 	{ PCI_VDEVICE(INTEL, 0x0F45), baytrail },
314 	{ PCI_VDEVICE(INTEL, 0x0F46), baytrail },
315 	{ PCI_VDEVICE(INTEL, 0x0F47), baytrail },
316 	/* Haswell */
317 	{ PCI_VDEVICE(INTEL, 0x9c61), haswell },
318 	{ PCI_VDEVICE(INTEL, 0x9c62), haswell },
319 	/* Braswell / Cherrytrail */
320 	{ PCI_VDEVICE(INTEL, 0x22C1), baytrail },
321 	{ PCI_VDEVICE(INTEL, 0x22C2), baytrail },
322 	{ PCI_VDEVICE(INTEL, 0x22C3), baytrail },
323 	{ PCI_VDEVICE(INTEL, 0x22C4), baytrail },
324 	{ PCI_VDEVICE(INTEL, 0x22C5), baytrail },
325 	{ PCI_VDEVICE(INTEL, 0x22C6), baytrail },
326 	{ PCI_VDEVICE(INTEL, 0x22C7), baytrail },
327 	{ 0,}
328 };
329 MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
330 
331 static struct pci_driver dw_i2c_driver = {
332 	.name		= DRIVER_NAME,
333 	.id_table	= i2_designware_pci_ids,
334 	.probe		= i2c_dw_pci_probe,
335 	.remove		= i2c_dw_pci_remove,
336 	.driver         = {
337 		.pm     = &i2c_dw_pm_ops,
338 	},
339 };
340 
341 module_pci_driver(dw_i2c_driver);
342 
343 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
344 MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
345 MODULE_LICENSE("GPL");
346