This source file includes following definitions.
- at91_twi_read
- at91_twi_write
- at91_disable_twi_interrupts
- at91_twi_irq_save
- at91_twi_irq_restore
- at91_init_twi_bus
- at91_twi_get_driver_data
- at91_twi_probe
- at91_twi_remove
- at91_twi_runtime_suspend
- at91_twi_runtime_resume
- at91_twi_suspend_noirq
- at91_twi_resume_noirq
- at91_twi_init
- at91_twi_exit
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16 #include <linux/clk.h>
17 #include <linux/err.h>
18 #include <linux/i2c.h>
19 #include <linux/io.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_device.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/pinctrl/consumer.h>
26
27 #include "i2c-at91.h"
28
29 unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg)
30 {
31 return readl_relaxed(dev->base + reg);
32 }
33
34 void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val)
35 {
36 writel_relaxed(val, dev->base + reg);
37 }
38
39 void at91_disable_twi_interrupts(struct at91_twi_dev *dev)
40 {
41 at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_INT_MASK);
42 }
43
44 void at91_twi_irq_save(struct at91_twi_dev *dev)
45 {
46 dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & AT91_TWI_INT_MASK;
47 at91_disable_twi_interrupts(dev);
48 }
49
50 void at91_twi_irq_restore(struct at91_twi_dev *dev)
51 {
52 at91_twi_write(dev, AT91_TWI_IER, dev->imr);
53 }
54
55 void at91_init_twi_bus(struct at91_twi_dev *dev)
56 {
57 at91_disable_twi_interrupts(dev);
58 at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST);
59 if (dev->slave_detected)
60 at91_init_twi_bus_slave(dev);
61 else
62 at91_init_twi_bus_master(dev);
63 }
64
65 static struct at91_twi_pdata at91rm9200_config = {
66 .clk_max_div = 5,
67 .clk_offset = 3,
68 .has_unre_flag = true,
69 .has_alt_cmd = false,
70 .has_hold_field = false,
71 };
72
73 static struct at91_twi_pdata at91sam9261_config = {
74 .clk_max_div = 5,
75 .clk_offset = 4,
76 .has_unre_flag = false,
77 .has_alt_cmd = false,
78 .has_hold_field = false,
79 };
80
81 static struct at91_twi_pdata at91sam9260_config = {
82 .clk_max_div = 7,
83 .clk_offset = 4,
84 .has_unre_flag = false,
85 .has_alt_cmd = false,
86 .has_hold_field = false,
87 };
88
89 static struct at91_twi_pdata at91sam9g20_config = {
90 .clk_max_div = 7,
91 .clk_offset = 4,
92 .has_unre_flag = false,
93 .has_alt_cmd = false,
94 .has_hold_field = false,
95 };
96
97 static struct at91_twi_pdata at91sam9g10_config = {
98 .clk_max_div = 7,
99 .clk_offset = 4,
100 .has_unre_flag = false,
101 .has_alt_cmd = false,
102 .has_hold_field = false,
103 };
104
105 static const struct platform_device_id at91_twi_devtypes[] = {
106 {
107 .name = "i2c-at91rm9200",
108 .driver_data = (unsigned long) &at91rm9200_config,
109 }, {
110 .name = "i2c-at91sam9261",
111 .driver_data = (unsigned long) &at91sam9261_config,
112 }, {
113 .name = "i2c-at91sam9260",
114 .driver_data = (unsigned long) &at91sam9260_config,
115 }, {
116 .name = "i2c-at91sam9g20",
117 .driver_data = (unsigned long) &at91sam9g20_config,
118 }, {
119 .name = "i2c-at91sam9g10",
120 .driver_data = (unsigned long) &at91sam9g10_config,
121 }, {
122
123 }
124 };
125
126 #if defined(CONFIG_OF)
127 static struct at91_twi_pdata at91sam9x5_config = {
128 .clk_max_div = 7,
129 .clk_offset = 4,
130 .has_unre_flag = false,
131 .has_alt_cmd = false,
132 .has_hold_field = false,
133 };
134
135 static struct at91_twi_pdata sama5d4_config = {
136 .clk_max_div = 7,
137 .clk_offset = 4,
138 .has_unre_flag = false,
139 .has_alt_cmd = false,
140 .has_hold_field = true,
141 };
142
143 static struct at91_twi_pdata sama5d2_config = {
144 .clk_max_div = 7,
145 .clk_offset = 3,
146 .has_unre_flag = true,
147 .has_alt_cmd = true,
148 .has_hold_field = true,
149 };
150
151 static const struct of_device_id atmel_twi_dt_ids[] = {
152 {
153 .compatible = "atmel,at91rm9200-i2c",
154 .data = &at91rm9200_config,
155 }, {
156 .compatible = "atmel,at91sam9260-i2c",
157 .data = &at91sam9260_config,
158 }, {
159 .compatible = "atmel,at91sam9261-i2c",
160 .data = &at91sam9261_config,
161 }, {
162 .compatible = "atmel,at91sam9g20-i2c",
163 .data = &at91sam9g20_config,
164 }, {
165 .compatible = "atmel,at91sam9g10-i2c",
166 .data = &at91sam9g10_config,
167 }, {
168 .compatible = "atmel,at91sam9x5-i2c",
169 .data = &at91sam9x5_config,
170 }, {
171 .compatible = "atmel,sama5d4-i2c",
172 .data = &sama5d4_config,
173 }, {
174 .compatible = "atmel,sama5d2-i2c",
175 .data = &sama5d2_config,
176 }, {
177
178 }
179 };
180 MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
181 #endif
182
183 static struct at91_twi_pdata *at91_twi_get_driver_data(
184 struct platform_device *pdev)
185 {
186 if (pdev->dev.of_node) {
187 const struct of_device_id *match;
188 match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node);
189 if (!match)
190 return NULL;
191 return (struct at91_twi_pdata *)match->data;
192 }
193 return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data;
194 }
195
196 static int at91_twi_probe(struct platform_device *pdev)
197 {
198 struct at91_twi_dev *dev;
199 struct resource *mem;
200 int rc;
201 u32 phy_addr;
202
203 dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
204 if (!dev)
205 return -ENOMEM;
206
207 dev->dev = &pdev->dev;
208
209 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
210 if (!mem)
211 return -ENODEV;
212 phy_addr = mem->start;
213
214 dev->pdata = at91_twi_get_driver_data(pdev);
215 if (!dev->pdata)
216 return -ENODEV;
217
218 dev->base = devm_ioremap_resource(&pdev->dev, mem);
219 if (IS_ERR(dev->base))
220 return PTR_ERR(dev->base);
221
222 dev->irq = platform_get_irq(pdev, 0);
223 if (dev->irq < 0)
224 return dev->irq;
225
226 platform_set_drvdata(pdev, dev);
227
228 dev->clk = devm_clk_get(dev->dev, NULL);
229 if (IS_ERR(dev->clk)) {
230 dev_err(dev->dev, "no clock defined\n");
231 return -ENODEV;
232 }
233 clk_prepare_enable(dev->clk);
234
235 snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91");
236 i2c_set_adapdata(&dev->adapter, dev);
237 dev->adapter.owner = THIS_MODULE;
238 dev->adapter.class = I2C_CLASS_DEPRECATED;
239 dev->adapter.dev.parent = dev->dev;
240 dev->adapter.nr = pdev->id;
241 dev->adapter.timeout = AT91_I2C_TIMEOUT;
242 dev->adapter.dev.of_node = pdev->dev.of_node;
243
244 dev->slave_detected = i2c_detect_slave_mode(&pdev->dev);
245
246 if (dev->slave_detected)
247 rc = at91_twi_probe_slave(pdev, phy_addr, dev);
248 else
249 rc = at91_twi_probe_master(pdev, phy_addr, dev);
250 if (rc)
251 return rc;
252
253 at91_init_twi_bus(dev);
254
255 pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT);
256 pm_runtime_use_autosuspend(dev->dev);
257 pm_runtime_set_active(dev->dev);
258 pm_runtime_enable(dev->dev);
259
260 rc = i2c_add_numbered_adapter(&dev->adapter);
261 if (rc) {
262 clk_disable_unprepare(dev->clk);
263
264 pm_runtime_disable(dev->dev);
265 pm_runtime_set_suspended(dev->dev);
266
267 return rc;
268 }
269
270 dev_info(dev->dev, "AT91 i2c bus driver (hw version: %#x).\n",
271 at91_twi_read(dev, AT91_TWI_VER));
272 return 0;
273 }
274
275 static int at91_twi_remove(struct platform_device *pdev)
276 {
277 struct at91_twi_dev *dev = platform_get_drvdata(pdev);
278
279 i2c_del_adapter(&dev->adapter);
280 clk_disable_unprepare(dev->clk);
281
282 pm_runtime_disable(dev->dev);
283 pm_runtime_set_suspended(dev->dev);
284
285 return 0;
286 }
287
288 #ifdef CONFIG_PM
289
290 static int at91_twi_runtime_suspend(struct device *dev)
291 {
292 struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
293
294 clk_disable_unprepare(twi_dev->clk);
295
296 pinctrl_pm_select_sleep_state(dev);
297
298 return 0;
299 }
300
301 static int at91_twi_runtime_resume(struct device *dev)
302 {
303 struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
304
305 pinctrl_pm_select_default_state(dev);
306
307 return clk_prepare_enable(twi_dev->clk);
308 }
309
310 static int at91_twi_suspend_noirq(struct device *dev)
311 {
312 if (!pm_runtime_status_suspended(dev))
313 at91_twi_runtime_suspend(dev);
314
315 return 0;
316 }
317
318 static int at91_twi_resume_noirq(struct device *dev)
319 {
320 struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
321 int ret;
322
323 if (!pm_runtime_status_suspended(dev)) {
324 ret = at91_twi_runtime_resume(dev);
325 if (ret)
326 return ret;
327 }
328
329 pm_runtime_mark_last_busy(dev);
330 pm_request_autosuspend(dev);
331
332 at91_init_twi_bus(twi_dev);
333
334 return 0;
335 }
336
337 static const struct dev_pm_ops at91_twi_pm = {
338 .suspend_noirq = at91_twi_suspend_noirq,
339 .resume_noirq = at91_twi_resume_noirq,
340 .runtime_suspend = at91_twi_runtime_suspend,
341 .runtime_resume = at91_twi_runtime_resume,
342 };
343
344 #define at91_twi_pm_ops (&at91_twi_pm)
345 #else
346 #define at91_twi_pm_ops NULL
347 #endif
348
349 static struct platform_driver at91_twi_driver = {
350 .probe = at91_twi_probe,
351 .remove = at91_twi_remove,
352 .id_table = at91_twi_devtypes,
353 .driver = {
354 .name = "at91_i2c",
355 .of_match_table = of_match_ptr(atmel_twi_dt_ids),
356 .pm = at91_twi_pm_ops,
357 },
358 };
359
360 static int __init at91_twi_init(void)
361 {
362 return platform_driver_register(&at91_twi_driver);
363 }
364
365 static void __exit at91_twi_exit(void)
366 {
367 platform_driver_unregister(&at91_twi_driver);
368 }
369
370 subsys_initcall(at91_twi_init);
371 module_exit(at91_twi_exit);
372
373 MODULE_AUTHOR("Nikolaus Voss <n.voss@weinmann.de>");
374 MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91");
375 MODULE_LICENSE("GPL");
376 MODULE_ALIAS("platform:at91_i2c");