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 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  * You should have received a copy of the GNU General Public License
24  * along with this program; if not, write to the Free Software
25  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
26  * ----------------------------------------------------------------------------
27  *
28  */
29 
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/delay.h>
33 #include <linux/i2c.h>
34 #include <linux/errno.h>
35 #include <linux/sched.h>
36 #include <linux/err.h>
37 #include <linux/interrupt.h>
38 #include <linux/io.h>
39 #include <linux/slab.h>
40 #include <linux/pci.h>
41 #include <linux/pm_runtime.h>
42 #include "i2c-designware-core.h"
43 
44 #define DRIVER_NAME "i2c-designware-pci"
45 
46 enum dw_pci_ctl_id_t {
47 	moorestown_0,
48 	moorestown_1,
49 	moorestown_2,
50 
51 	medfield_0,
52 	medfield_1,
53 	medfield_2,
54 	medfield_3,
55 	medfield_4,
56 	medfield_5,
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 };
66 
67 #define INTEL_MID_STD_CFG  (DW_IC_CON_MASTER |			\
68 				DW_IC_CON_SLAVE_DISABLE |	\
69 				DW_IC_CON_RESTART_EN)
70 
71 static struct  dw_pci_controller  dw_pci_controllers[] = {
72 	[moorestown_0] = {
73 		.bus_num     = 0,
74 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
75 		.tx_fifo_depth = 32,
76 		.rx_fifo_depth = 32,
77 		.clk_khz      = 25000,
78 	},
79 	[moorestown_1] = {
80 		.bus_num     = 1,
81 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
82 		.tx_fifo_depth = 32,
83 		.rx_fifo_depth = 32,
84 		.clk_khz      = 25000,
85 	},
86 	[moorestown_2] = {
87 		.bus_num     = 2,
88 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
89 		.tx_fifo_depth = 32,
90 		.rx_fifo_depth = 32,
91 		.clk_khz      = 25000,
92 	},
93 	[medfield_0] = {
94 		.bus_num     = 0,
95 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
96 		.tx_fifo_depth = 32,
97 		.rx_fifo_depth = 32,
98 		.clk_khz      = 25000,
99 	},
100 	[medfield_1] = {
101 		.bus_num     = 1,
102 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
103 		.tx_fifo_depth = 32,
104 		.rx_fifo_depth = 32,
105 		.clk_khz      = 25000,
106 	},
107 	[medfield_2] = {
108 		.bus_num     = 2,
109 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
110 		.tx_fifo_depth = 32,
111 		.rx_fifo_depth = 32,
112 		.clk_khz      = 25000,
113 	},
114 	[medfield_3] = {
115 		.bus_num     = 3,
116 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_STD,
117 		.tx_fifo_depth = 32,
118 		.rx_fifo_depth = 32,
119 		.clk_khz      = 25000,
120 	},
121 	[medfield_4] = {
122 		.bus_num     = 4,
123 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
124 		.tx_fifo_depth = 32,
125 		.rx_fifo_depth = 32,
126 		.clk_khz      = 25000,
127 	},
128 	[medfield_5] = {
129 		.bus_num     = 5,
130 		.bus_cfg   = INTEL_MID_STD_CFG | DW_IC_CON_SPEED_FAST,
131 		.tx_fifo_depth = 32,
132 		.rx_fifo_depth = 32,
133 		.clk_khz      = 25000,
134 	},
135 };
136 static struct i2c_algorithm i2c_dw_algo = {
137 	.master_xfer	= i2c_dw_xfer,
138 	.functionality	= i2c_dw_func,
139 };
140 
141 static int i2c_dw_pci_suspend(struct device *dev)
142 {
143 	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
144 	struct dw_i2c_dev *i2c = pci_get_drvdata(pdev);
145 	int err;
146 
147 
148 	i2c_dw_disable(i2c);
149 
150 	err = pci_save_state(pdev);
151 	if (err) {
152 		dev_err(&pdev->dev, "pci_save_state failed\n");
153 		return err;
154 	}
155 
156 	err = pci_set_power_state(pdev, PCI_D3hot);
157 	if (err) {
158 		dev_err(&pdev->dev, "pci_set_power_state failed\n");
159 		return err;
160 	}
161 
162 	return 0;
163 }
164 
165 static int i2c_dw_pci_resume(struct device *dev)
166 {
167 	struct pci_dev *pdev = container_of(dev, struct pci_dev, dev);
168 	struct dw_i2c_dev *i2c = pci_get_drvdata(pdev);
169 	int err;
170 	u32 enabled;
171 
172 	enabled = i2c_dw_is_enabled(i2c);
173 	if (enabled)
174 		return 0;
175 
176 	err = pci_set_power_state(pdev, PCI_D0);
177 	if (err) {
178 		dev_err(&pdev->dev, "pci_set_power_state() failed\n");
179 		return err;
180 	}
181 
182 	pci_restore_state(pdev);
183 
184 	i2c_dw_init(i2c);
185 	return 0;
186 }
187 
188 static int i2c_dw_pci_runtime_idle(struct device *dev)
189 {
190 	int err = pm_schedule_suspend(dev, 500);
191 	dev_dbg(dev, "runtime_idle called\n");
192 
193 	if (err != 0)
194 		return 0;
195 	return -EBUSY;
196 }
197 
198 static const struct dev_pm_ops i2c_dw_pm_ops = {
199 	.resume         = i2c_dw_pci_resume,
200 	.suspend        = i2c_dw_pci_suspend,
201 	SET_RUNTIME_PM_OPS(i2c_dw_pci_suspend, i2c_dw_pci_resume,
202 			   i2c_dw_pci_runtime_idle)
203 };
204 
205 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
206 {
207 	return dev->controller->clk_khz;
208 }
209 
210 static int __devinit i2c_dw_pci_probe(struct pci_dev *pdev,
211 const struct pci_device_id *id)
212 {
213 	struct dw_i2c_dev *dev;
214 	struct i2c_adapter *adap;
215 	unsigned long start, len;
216 	void __iomem *base;
217 	int r;
218 	struct  dw_pci_controller *controller;
219 
220 	if (id->driver_data >= ARRAY_SIZE(dw_pci_controllers)) {
221 		printk(KERN_ERR "dw_i2c_pci_probe: invalid driver data %ld\n",
222 			id->driver_data);
223 		return -EINVAL;
224 	}
225 
226 	controller = &dw_pci_controllers[id->driver_data];
227 
228 	r = pci_enable_device(pdev);
229 	if (r) {
230 		dev_err(&pdev->dev, "Failed to enable I2C PCI device (%d)\n",
231 			r);
232 		goto exit;
233 	}
234 
235 	/* Determine the address of the I2C area */
236 	start = pci_resource_start(pdev, 0);
237 	len = pci_resource_len(pdev, 0);
238 	if (!start || len == 0) {
239 		dev_err(&pdev->dev, "base address not set\n");
240 		r = -ENODEV;
241 		goto exit;
242 	}
243 
244 	r = pci_request_region(pdev, 0, DRIVER_NAME);
245 	if (r) {
246 		dev_err(&pdev->dev, "failed to request I2C region "
247 			"0x%lx-0x%lx\n", start,
248 			(unsigned long)pci_resource_end(pdev, 0));
249 		goto exit;
250 	}
251 
252 	base = ioremap_nocache(start, len);
253 	if (!base) {
254 		dev_err(&pdev->dev, "I/O memory remapping failed\n");
255 		r = -ENOMEM;
256 		goto err_release_region;
257 	}
258 
259 
260 	dev = kzalloc(sizeof(struct dw_i2c_dev), GFP_KERNEL);
261 	if (!dev) {
262 		r = -ENOMEM;
263 		goto err_release_region;
264 	}
265 
266 	init_completion(&dev->cmd_complete);
267 	mutex_init(&dev->lock);
268 	dev->clk = NULL;
269 	dev->controller = controller;
270 	dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
271 	dev->base = base;
272 	dev->dev = get_device(&pdev->dev);
273 	dev->functionality =
274 		I2C_FUNC_I2C |
275 		I2C_FUNC_SMBUS_BYTE |
276 		I2C_FUNC_SMBUS_BYTE_DATA |
277 		I2C_FUNC_SMBUS_WORD_DATA |
278 		I2C_FUNC_SMBUS_I2C_BLOCK;
279 	dev->master_cfg =  controller->bus_cfg;
280 
281 	pci_set_drvdata(pdev, dev);
282 
283 	dev->tx_fifo_depth = controller->tx_fifo_depth;
284 	dev->rx_fifo_depth = controller->rx_fifo_depth;
285 	r = i2c_dw_init(dev);
286 	if (r)
287 		goto err_iounmap;
288 
289 	adap = &dev->adapter;
290 	i2c_set_adapdata(adap, dev);
291 	adap->owner = THIS_MODULE;
292 	adap->class = 0;
293 	adap->algo = &i2c_dw_algo;
294 	adap->dev.parent = &pdev->dev;
295 	adap->nr = controller->bus_num;
296 	snprintf(adap->name, sizeof(adap->name), "i2c-designware-pci-%d",
297 		adap->nr);
298 
299 	r = request_irq(pdev->irq, i2c_dw_isr, IRQF_SHARED, adap->name, dev);
300 	if (r) {
301 		dev_err(&pdev->dev, "failure requesting irq %i\n", dev->irq);
302 		goto err_iounmap;
303 	}
304 
305 	i2c_dw_disable_int(dev);
306 	i2c_dw_clear_int(dev);
307 	r = i2c_add_numbered_adapter(adap);
308 	if (r) {
309 		dev_err(&pdev->dev, "failure adding adapter\n");
310 		goto err_free_irq;
311 	}
312 
313 	pm_runtime_put_noidle(&pdev->dev);
314 	pm_runtime_allow(&pdev->dev);
315 
316 	return 0;
317 
318 err_free_irq:
319 	free_irq(pdev->irq, dev);
320 err_iounmap:
321 	iounmap(dev->base);
322 	pci_set_drvdata(pdev, NULL);
323 	put_device(&pdev->dev);
324 	kfree(dev);
325 err_release_region:
326 	pci_release_region(pdev, 0);
327 exit:
328 	return r;
329 }
330 
331 static void __devexit i2c_dw_pci_remove(struct pci_dev *pdev)
332 {
333 	struct dw_i2c_dev *dev = pci_get_drvdata(pdev);
334 
335 	i2c_dw_disable(dev);
336 	pm_runtime_forbid(&pdev->dev);
337 	pm_runtime_get_noresume(&pdev->dev);
338 
339 	pci_set_drvdata(pdev, NULL);
340 	i2c_del_adapter(&dev->adapter);
341 	put_device(&pdev->dev);
342 
343 	free_irq(dev->irq, dev);
344 	kfree(dev);
345 	pci_release_region(pdev, 0);
346 }
347 
348 /* work with hotplug and coldplug */
349 MODULE_ALIAS("i2c_designware-pci");
350 
351 static DEFINE_PCI_DEVICE_TABLE(i2_designware_pci_ids) = {
352 	/* Moorestown */
353 	{ PCI_VDEVICE(INTEL, 0x0802), moorestown_0 },
354 	{ PCI_VDEVICE(INTEL, 0x0803), moorestown_1 },
355 	{ PCI_VDEVICE(INTEL, 0x0804), moorestown_2 },
356 	/* Medfield */
357 	{ PCI_VDEVICE(INTEL, 0x0817), medfield_3,},
358 	{ PCI_VDEVICE(INTEL, 0x0818), medfield_4 },
359 	{ PCI_VDEVICE(INTEL, 0x0819), medfield_5 },
360 	{ PCI_VDEVICE(INTEL, 0x082C), medfield_0 },
361 	{ PCI_VDEVICE(INTEL, 0x082D), medfield_1 },
362 	{ PCI_VDEVICE(INTEL, 0x082E), medfield_2 },
363 	{ 0,}
364 };
365 MODULE_DEVICE_TABLE(pci, i2_designware_pci_ids);
366 
367 static struct pci_driver dw_i2c_driver = {
368 	.name		= DRIVER_NAME,
369 	.id_table	= i2_designware_pci_ids,
370 	.probe		= i2c_dw_pci_probe,
371 	.remove		= __devexit_p(i2c_dw_pci_remove),
372 	.driver         = {
373 		.pm     = &i2c_dw_pm_ops,
374 	},
375 };
376 
377 static int __init dw_i2c_init_driver(void)
378 {
379 	return  pci_register_driver(&dw_i2c_driver);
380 }
381 module_init(dw_i2c_init_driver);
382 
383 static void __exit dw_i2c_exit_driver(void)
384 {
385 	pci_unregister_driver(&dw_i2c_driver);
386 }
387 module_exit(dw_i2c_exit_driver);
388 
389 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
390 MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
391 MODULE_LICENSE("GPL");
392