Merge branch 'i2c/for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa...
[muen/linux.git] / drivers / i2c / busses / i2c-designware-platdrv.c
1 /*
2  * Synopsys DesignWare I2C adapter driver.
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  *
10  * ----------------------------------------------------------------------------
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  * ----------------------------------------------------------------------------
22  *
23  */
24 #include <linux/acpi.h>
25 #include <linux/clk-provider.h>
26 #include <linux/clk.h>
27 #include <linux/delay.h>
28 #include <linux/dmi.h>
29 #include <linux/err.h>
30 #include <linux/errno.h>
31 #include <linux/i2c.h>
32 #include <linux/interrupt.h>
33 #include <linux/io.h>
34 #include <linux/kernel.h>
35 #include <linux/module.h>
36 #include <linux/of.h>
37 #include <linux/platform_data/i2c-designware.h>
38 #include <linux/platform_device.h>
39 #include <linux/pm.h>
40 #include <linux/pm_runtime.h>
41 #include <linux/property.h>
42 #include <linux/reset.h>
43 #include <linux/sched.h>
44 #include <linux/slab.h>
45
46 #include "i2c-designware-core.h"
47
48 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
49 {
50         return clk_get_rate(dev->clk)/1000;
51 }
52
53 #ifdef CONFIG_ACPI
54 /*
55  * The HCNT/LCNT information coming from ACPI should be the most accurate
56  * for given platform. However, some systems get it wrong. On such systems
57  * we get better results by calculating those based on the input clock.
58  */
59 static const struct dmi_system_id dw_i2c_no_acpi_params[] = {
60         {
61                 .ident = "Dell Inspiron 7348",
62                 .matches = {
63                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
64                         DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"),
65                 },
66         },
67         { }
68 };
69
70 static void dw_i2c_acpi_params(struct platform_device *pdev, char method[],
71                                u16 *hcnt, u16 *lcnt, u32 *sda_hold)
72 {
73         struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER };
74         acpi_handle handle = ACPI_HANDLE(&pdev->dev);
75         union acpi_object *obj;
76
77         if (dmi_check_system(dw_i2c_no_acpi_params))
78                 return;
79
80         if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf)))
81                 return;
82
83         obj = (union acpi_object *)buf.pointer;
84         if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 3) {
85                 const union acpi_object *objs = obj->package.elements;
86
87                 *hcnt = (u16)objs[0].integer.value;
88                 *lcnt = (u16)objs[1].integer.value;
89                 *sda_hold = (u32)objs[2].integer.value;
90         }
91
92         kfree(buf.pointer);
93 }
94
95 static int dw_i2c_acpi_configure(struct platform_device *pdev)
96 {
97         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
98         u32 ss_ht = 0, fp_ht = 0, hs_ht = 0, fs_ht = 0;
99         acpi_handle handle = ACPI_HANDLE(&pdev->dev);
100         const struct acpi_device_id *id;
101         struct acpi_device *adev;
102         const char *uid;
103
104         dev->adapter.nr = -1;
105         dev->tx_fifo_depth = 32;
106         dev->rx_fifo_depth = 32;
107
108         /*
109          * Try to get SDA hold time and *CNT values from an ACPI method for
110          * selected speed modes.
111          */
112         dw_i2c_acpi_params(pdev, "SSCN", &dev->ss_hcnt, &dev->ss_lcnt, &ss_ht);
113         dw_i2c_acpi_params(pdev, "FPCN", &dev->fp_hcnt, &dev->fp_lcnt, &fp_ht);
114         dw_i2c_acpi_params(pdev, "HSCN", &dev->hs_hcnt, &dev->hs_lcnt, &hs_ht);
115         dw_i2c_acpi_params(pdev, "FMCN", &dev->fs_hcnt, &dev->fs_lcnt, &fs_ht);
116
117         switch (dev->clk_freq) {
118         case 100000:
119                 dev->sda_hold_time = ss_ht;
120                 break;
121         case 1000000:
122                 dev->sda_hold_time = fp_ht;
123                 break;
124         case 3400000:
125                 dev->sda_hold_time = hs_ht;
126                 break;
127         case 400000:
128         default:
129                 dev->sda_hold_time = fs_ht;
130                 break;
131         }
132
133         id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
134         if (id && id->driver_data)
135                 dev->flags |= (u32)id->driver_data;
136
137         if (acpi_bus_get_device(handle, &adev))
138                 return -ENODEV;
139
140         /*
141          * Cherrytrail I2C7 gets used for the PMIC which gets accessed
142          * through ACPI opregions during late suspend / early resume
143          * disable pm for it.
144          */
145         uid = adev->pnp.unique_id;
146         if ((dev->flags & MODEL_CHERRYTRAIL) && !strcmp(uid, "7"))
147                 dev->pm_disabled = true;
148
149         return 0;
150 }
151
152 static const struct acpi_device_id dw_i2c_acpi_match[] = {
153         { "INT33C2", 0 },
154         { "INT33C3", 0 },
155         { "INT3432", 0 },
156         { "INT3433", 0 },
157         { "80860F41", 0 },
158         { "808622C1", MODEL_CHERRYTRAIL },
159         { "AMD0010", ACCESS_INTR_MASK },
160         { "AMDI0010", ACCESS_INTR_MASK },
161         { "AMDI0510", 0 },
162         { "APMC0D0F", 0 },
163         { "HISI02A1", 0 },
164         { "HISI02A2", 0 },
165         { }
166 };
167 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
168 #else
169 static inline int dw_i2c_acpi_configure(struct platform_device *pdev)
170 {
171         return -ENODEV;
172 }
173 #endif
174
175 static void i2c_dw_configure_master(struct dw_i2c_dev *dev)
176 {
177         dev->functionality = I2C_FUNC_10BIT_ADDR | DW_IC_DEFAULT_FUNCTIONALITY;
178
179         dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
180                           DW_IC_CON_RESTART_EN;
181
182         dev->mode = DW_IC_MASTER;
183
184         switch (dev->clk_freq) {
185         case 100000:
186                 dev->master_cfg |= DW_IC_CON_SPEED_STD;
187                 break;
188         case 3400000:
189                 dev->master_cfg |= DW_IC_CON_SPEED_HIGH;
190                 break;
191         default:
192                 dev->master_cfg |= DW_IC_CON_SPEED_FAST;
193         }
194 }
195
196 static void i2c_dw_configure_slave(struct dw_i2c_dev *dev)
197 {
198         dev->functionality = I2C_FUNC_SLAVE | DW_IC_DEFAULT_FUNCTIONALITY;
199
200         dev->slave_cfg = DW_IC_CON_RX_FIFO_FULL_HLD_CTRL |
201                          DW_IC_CON_RESTART_EN | DW_IC_CON_STOP_DET_IFADDRESSED;
202
203         dev->mode = DW_IC_SLAVE;
204
205         switch (dev->clk_freq) {
206         case 100000:
207                 dev->slave_cfg |= DW_IC_CON_SPEED_STD;
208                 break;
209         case 3400000:
210                 dev->slave_cfg |= DW_IC_CON_SPEED_HIGH;
211                 break;
212         default:
213                 dev->slave_cfg |= DW_IC_CON_SPEED_FAST;
214         }
215 }
216
217 static int i2c_dw_plat_prepare_clk(struct dw_i2c_dev *i_dev, bool prepare)
218 {
219         if (IS_ERR(i_dev->clk))
220                 return PTR_ERR(i_dev->clk);
221
222         if (prepare)
223                 return clk_prepare_enable(i_dev->clk);
224
225         clk_disable_unprepare(i_dev->clk);
226         return 0;
227 }
228
229 static void dw_i2c_set_fifo_size(struct dw_i2c_dev *dev, int id)
230 {
231         u32 param, tx_fifo_depth, rx_fifo_depth;
232
233         /*
234          * Try to detect the FIFO depth if not set by interface driver,
235          * the depth could be from 2 to 256 from HW spec.
236          */
237         param = i2c_dw_read_comp_param(dev);
238         tx_fifo_depth = ((param >> 16) & 0xff) + 1;
239         rx_fifo_depth = ((param >> 8)  & 0xff) + 1;
240         if (!dev->tx_fifo_depth) {
241                 dev->tx_fifo_depth = tx_fifo_depth;
242                 dev->rx_fifo_depth = rx_fifo_depth;
243                 dev->adapter.nr = id;
244         } else if (tx_fifo_depth >= 2) {
245                 dev->tx_fifo_depth = min_t(u32, dev->tx_fifo_depth,
246                                 tx_fifo_depth);
247                 dev->rx_fifo_depth = min_t(u32, dev->rx_fifo_depth,
248                                 rx_fifo_depth);
249         }
250 }
251
252 static int dw_i2c_plat_probe(struct platform_device *pdev)
253 {
254         struct dw_i2c_platform_data *pdata = dev_get_platdata(&pdev->dev);
255         struct i2c_adapter *adap;
256         struct dw_i2c_dev *dev;
257         u32 acpi_speed, ht = 0;
258         struct resource *mem;
259         int i, irq, ret;
260         const int supported_speeds[] = { 0, 100000, 400000, 1000000, 3400000 };
261
262         irq = platform_get_irq(pdev, 0);
263         if (irq < 0)
264                 return irq;
265
266         dev = devm_kzalloc(&pdev->dev, sizeof(struct dw_i2c_dev), GFP_KERNEL);
267         if (!dev)
268                 return -ENOMEM;
269
270         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
271         dev->base = devm_ioremap_resource(&pdev->dev, mem);
272         if (IS_ERR(dev->base))
273                 return PTR_ERR(dev->base);
274
275         dev->dev = &pdev->dev;
276         dev->irq = irq;
277         platform_set_drvdata(pdev, dev);
278
279         dev->rst = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
280         if (IS_ERR(dev->rst)) {
281                 if (PTR_ERR(dev->rst) == -EPROBE_DEFER)
282                         return -EPROBE_DEFER;
283         } else {
284                 reset_control_deassert(dev->rst);
285         }
286
287         if (pdata) {
288                 dev->clk_freq = pdata->i2c_scl_freq;
289         } else {
290                 device_property_read_u32(&pdev->dev, "i2c-sda-hold-time-ns",
291                                          &ht);
292                 device_property_read_u32(&pdev->dev, "i2c-sda-falling-time-ns",
293                                          &dev->sda_falling_time);
294                 device_property_read_u32(&pdev->dev, "i2c-scl-falling-time-ns",
295                                          &dev->scl_falling_time);
296                 device_property_read_u32(&pdev->dev, "clock-frequency",
297                                          &dev->clk_freq);
298         }
299
300         acpi_speed = i2c_acpi_find_bus_speed(&pdev->dev);
301         /*
302          * Some DSTDs use a non standard speed, round down to the lowest
303          * standard speed.
304          */
305         for (i = 1; i < ARRAY_SIZE(supported_speeds); i++) {
306                 if (acpi_speed < supported_speeds[i])
307                         break;
308         }
309         acpi_speed = supported_speeds[i - 1];
310
311         /*
312          * Find bus speed from the "clock-frequency" device property, ACPI
313          * or by using fast mode if neither is set.
314          */
315         if (acpi_speed && dev->clk_freq)
316                 dev->clk_freq = min(dev->clk_freq, acpi_speed);
317         else if (acpi_speed || dev->clk_freq)
318                 dev->clk_freq = max(dev->clk_freq, acpi_speed);
319         else
320                 dev->clk_freq = 400000;
321
322         if (has_acpi_companion(&pdev->dev))
323                 dw_i2c_acpi_configure(pdev);
324
325         /*
326          * Only standard mode at 100kHz, fast mode at 400kHz,
327          * fast mode plus at 1MHz and high speed mode at 3.4MHz are supported.
328          */
329         if (dev->clk_freq != 100000 && dev->clk_freq != 400000
330             && dev->clk_freq != 1000000 && dev->clk_freq != 3400000) {
331                 dev_err(&pdev->dev,
332                         "%d Hz is unsupported, only 100kHz, 400kHz, 1MHz and 3.4MHz are supported\n",
333                         dev->clk_freq);
334                 ret = -EINVAL;
335                 goto exit_reset;
336         }
337
338         ret = i2c_dw_probe_lock_support(dev);
339         if (ret)
340                 goto exit_reset;
341
342         if (i2c_detect_slave_mode(&pdev->dev))
343                 i2c_dw_configure_slave(dev);
344         else
345                 i2c_dw_configure_master(dev);
346
347         dev->clk = devm_clk_get(&pdev->dev, NULL);
348         if (!i2c_dw_plat_prepare_clk(dev, true)) {
349                 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
350
351                 if (!dev->sda_hold_time && ht)
352                         dev->sda_hold_time = div_u64(
353                                 (u64)dev->get_clk_rate_khz(dev) * ht + 500000,
354                                 1000000);
355         }
356
357         dw_i2c_set_fifo_size(dev, pdev->id);
358
359         adap = &dev->adapter;
360         adap->owner = THIS_MODULE;
361         adap->class = I2C_CLASS_DEPRECATED;
362         ACPI_COMPANION_SET(&adap->dev, ACPI_COMPANION(&pdev->dev));
363         adap->dev.of_node = pdev->dev.of_node;
364
365         if (dev->pm_disabled) {
366                 pm_runtime_forbid(&pdev->dev);
367         } else {
368                 pm_runtime_set_autosuspend_delay(&pdev->dev, 1000);
369                 pm_runtime_use_autosuspend(&pdev->dev);
370                 pm_runtime_set_active(&pdev->dev);
371                 pm_runtime_enable(&pdev->dev);
372         }
373
374         if (dev->mode == DW_IC_SLAVE)
375                 ret = i2c_dw_probe_slave(dev);
376         else
377                 ret = i2c_dw_probe(dev);
378
379         if (ret)
380                 goto exit_probe;
381
382         return ret;
383
384 exit_probe:
385         if (!dev->pm_disabled)
386                 pm_runtime_disable(&pdev->dev);
387 exit_reset:
388         if (!IS_ERR_OR_NULL(dev->rst))
389                 reset_control_assert(dev->rst);
390         return ret;
391 }
392
393 static int dw_i2c_plat_remove(struct platform_device *pdev)
394 {
395         struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
396
397         pm_runtime_get_sync(&pdev->dev);
398
399         i2c_del_adapter(&dev->adapter);
400
401         dev->disable(dev);
402
403         pm_runtime_dont_use_autosuspend(&pdev->dev);
404         pm_runtime_put_sync(&pdev->dev);
405         if (!dev->pm_disabled)
406                 pm_runtime_disable(&pdev->dev);
407         if (!IS_ERR_OR_NULL(dev->rst))
408                 reset_control_assert(dev->rst);
409
410         i2c_dw_remove_lock_support(dev);
411
412         return 0;
413 }
414
415 #ifdef CONFIG_OF
416 static const struct of_device_id dw_i2c_of_match[] = {
417         { .compatible = "snps,designware-i2c", },
418         {},
419 };
420 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
421 #endif
422
423 #ifdef CONFIG_PM_SLEEP
424 static int dw_i2c_plat_prepare(struct device *dev)
425 {
426         return pm_runtime_suspended(dev);
427 }
428
429 static void dw_i2c_plat_complete(struct device *dev)
430 {
431         if (dev->power.direct_complete)
432                 pm_request_resume(dev);
433 }
434 #else
435 #define dw_i2c_plat_prepare     NULL
436 #define dw_i2c_plat_complete    NULL
437 #endif
438
439 #ifdef CONFIG_PM
440 static int dw_i2c_plat_runtime_suspend(struct device *dev)
441 {
442         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
443
444         i_dev->disable(i_dev);
445         i2c_dw_plat_prepare_clk(i_dev, false);
446
447         return 0;
448 }
449
450 static int dw_i2c_plat_resume(struct device *dev)
451 {
452         struct dw_i2c_dev *i_dev = dev_get_drvdata(dev);
453
454         i2c_dw_plat_prepare_clk(i_dev, true);
455         i_dev->init(i_dev);
456
457         return 0;
458 }
459
460 #ifdef CONFIG_PM_SLEEP
461 static int dw_i2c_plat_suspend(struct device *dev)
462 {
463         pm_runtime_resume(dev);
464         return dw_i2c_plat_runtime_suspend(dev);
465 }
466 #endif
467
468 static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
469         .prepare = dw_i2c_plat_prepare,
470         .complete = dw_i2c_plat_complete,
471         SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
472         SET_RUNTIME_PM_OPS(dw_i2c_plat_runtime_suspend,
473                            dw_i2c_plat_resume,
474                            NULL)
475 };
476
477 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
478 #else
479 #define DW_I2C_DEV_PMOPS NULL
480 #endif
481
482 /* Work with hotplug and coldplug */
483 MODULE_ALIAS("platform:i2c_designware");
484
485 static struct platform_driver dw_i2c_driver = {
486         .probe = dw_i2c_plat_probe,
487         .remove = dw_i2c_plat_remove,
488         .driver         = {
489                 .name   = "i2c_designware",
490                 .of_match_table = of_match_ptr(dw_i2c_of_match),
491                 .acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
492                 .pm     = DW_I2C_DEV_PMOPS,
493         },
494 };
495
496 static int __init dw_i2c_init_driver(void)
497 {
498         return platform_driver_register(&dw_i2c_driver);
499 }
500 subsys_initcall(dw_i2c_init_driver);
501
502 static void __exit dw_i2c_exit_driver(void)
503 {
504         platform_driver_unregister(&dw_i2c_driver);
505 }
506 module_exit(dw_i2c_exit_driver);
507
508 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
509 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
510 MODULE_LICENSE("GPL");