1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Synopsys DesignWare I2C adapter driver.
4 *
5 * Based on the TI DAVINCI I2C adapter driver.
6 *
7 * Copyright (C) 2006 Texas Instruments.
8 * Copyright (C) 2007 MontaVista Software Inc.
9 * Copyright (C) 2009 Provigent Ltd.
10 */
11 #include <linux/clk-provider.h>
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/dmi.h>
15 #include <linux/err.h>
16 #include <linux/errno.h>
17 #include <linux/i2c.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/kernel.h>
21 #include <linux/mfd/syscon.h>
22 #include <linux/module.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/property.h>
27 #include <linux/regmap.h>
28 #include <linux/reset.h>
29 #include <linux/sched.h>
30 #include <linux/slab.h>
31 #include <linux/units.h>
32
33 #include "i2c-designware-core.h"
34
i2c_dw_get_clk_rate_khz(struct dw_i2c_dev * dev)35 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
36 {
37 return clk_get_rate(dev->clk) / KILO;
38 }
39
40 #ifdef CONFIG_OF
41 #define BT1_I2C_CTL 0x100
42 #define BT1_I2C_CTL_ADDR_MASK GENMASK(7, 0)
43 #define BT1_I2C_CTL_WR BIT(8)
44 #define BT1_I2C_CTL_GO BIT(31)
45 #define BT1_I2C_DI 0x104
46 #define BT1_I2C_DO 0x108
47
bt1_i2c_read(void * context,unsigned int reg,unsigned int * val)48 static int bt1_i2c_read(void *context, unsigned int reg, unsigned int *val)
49 {
50 struct dw_i2c_dev *dev = context;
51 int ret;
52
53 /*
54 * Note these methods shouldn't ever fail because the system controller
55 * registers are memory mapped. We check the return value just in case.
56 */
57 ret = regmap_write(dev->sysmap, BT1_I2C_CTL,
58 BT1_I2C_CTL_GO | (reg & BT1_I2C_CTL_ADDR_MASK));
59 if (ret)
60 return ret;
61
62 return regmap_read(dev->sysmap, BT1_I2C_DO, val);
63 }
64
bt1_i2c_write(void * context,unsigned int reg,unsigned int val)65 static int bt1_i2c_write(void *context, unsigned int reg, unsigned int val)
66 {
67 struct dw_i2c_dev *dev = context;
68 int ret;
69
70 ret = regmap_write(dev->sysmap, BT1_I2C_DI, val);
71 if (ret)
72 return ret;
73
74 return regmap_write(dev->sysmap, BT1_I2C_CTL,
75 BT1_I2C_CTL_GO | BT1_I2C_CTL_WR | (reg & BT1_I2C_CTL_ADDR_MASK));
76 }
77
78 static const struct regmap_config bt1_i2c_cfg = {
79 .reg_bits = 32,
80 .val_bits = 32,
81 .reg_stride = 4,
82 .fast_io = true,
83 .reg_read = bt1_i2c_read,
84 .reg_write = bt1_i2c_write,
85 .max_register = DW_IC_COMP_TYPE,
86 };
87
bt1_i2c_request_regs(struct dw_i2c_dev * dev)88 static int bt1_i2c_request_regs(struct dw_i2c_dev *dev)
89 {
90 dev->sysmap = syscon_node_to_regmap(dev->dev->of_node->parent);
91 if (IS_ERR(dev->sysmap))
92 return PTR_ERR(dev->sysmap);
93
94 dev->map = devm_regmap_init(dev->dev, NULL, dev, &bt1_i2c_cfg);
95 return PTR_ERR_OR_ZERO(dev->map);
96 }
97 #else
bt1_i2c_request_regs(struct dw_i2c_dev * dev)98 static int bt1_i2c_request_regs(struct dw_i2c_dev *dev)
99 {
100 return -ENODEV;
101 }
102 #endif
103
dw_i2c_get_parent_regmap(struct dw_i2c_dev * dev)104 static int dw_i2c_get_parent_regmap(struct dw_i2c_dev *dev)
105 {
106 dev->map = dev_get_regmap(dev->dev->parent, NULL);
107 if (!dev->map)
108 return -ENODEV;
109
110 return 0;
111 }
112
dw_i2c_plat_pm_cleanup(struct dw_i2c_dev * dev)113 static void dw_i2c_plat_pm_cleanup(struct dw_i2c_dev *dev)
114 {
115 pm_runtime_disable(dev->dev);
116
117 if (dev->shared_with_punit)
118 pm_runtime_put_noidle(dev->dev);
119 }
120
dw_i2c_plat_request_regs(struct dw_i2c_dev * dev)121 static int dw_i2c_plat_request_regs(struct dw_i2c_dev *dev)
122 {
123 struct platform_device *pdev = to_platform_device(dev->dev);
124 int ret;
125
126 if (device_is_compatible(dev->dev, "intel,xe-i2c"))
127 return dw_i2c_get_parent_regmap(dev);
128
129 switch (dev->flags & MODEL_MASK) {
130 case MODEL_BAIKAL_BT1:
131 ret = bt1_i2c_request_regs(dev);
132 break;
133 case MODEL_WANGXUN_SP:
134 ret = dw_i2c_get_parent_regmap(dev);
135 break;
136 default:
137 dev->base = devm_platform_ioremap_resource(pdev, 0);
138 ret = PTR_ERR_OR_ZERO(dev->base);
139 break;
140 }
141
142 return ret;
143 }
144
145 static const struct dmi_system_id dw_i2c_hwmon_class_dmi[] = {
146 {
147 .ident = "Qtechnology QT5222",
148 .matches = {
149 DMI_MATCH(DMI_SYS_VENDOR, "Qtechnology"),
150 DMI_MATCH(DMI_PRODUCT_NAME, "QT5222"),
151 },
152 },
153 { } /* terminate list */
154 };
155
156 static const struct i2c_dw_semaphore_callbacks i2c_dw_semaphore_cb_table[] = {
157 #ifdef CONFIG_I2C_DESIGNWARE_BAYTRAIL
158 {
159 .probe = i2c_dw_baytrail_probe_lock_support,
160 },
161 #endif
162 #ifdef CONFIG_I2C_DESIGNWARE_AMDPSP
163 {
164 .probe = i2c_dw_amdpsp_probe_lock_support,
165 },
166 #endif
167 {}
168 };
169
i2c_dw_probe_lock_support(struct dw_i2c_dev * dev)170 static int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev)
171 {
172 const struct i2c_dw_semaphore_callbacks *ptr;
173 int i = 0;
174 int ret;
175
176 dev->semaphore_idx = -1;
177
178 for (ptr = i2c_dw_semaphore_cb_table; ptr->probe; ptr++) {
179 ret = ptr->probe(dev);
180 if (ret) {
181 /*
182 * If there is no semaphore device attached to this
183 * controller, we shouldn't abort general i2c_controller
184 * probe.
185 */
186 if (ret != -ENODEV)
187 return ret;
188
189 i++;
190 continue;
191 }
192
193 dev->semaphore_idx = i;
194 break;
195 }
196
197 return 0;
198 }
199
i2c_dw_remove_lock_support(struct dw_i2c_dev * dev)200 static void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev)
201 {
202 if (dev->semaphore_idx < 0)
203 return;
204
205 if (i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove)
206 i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove(dev);
207 }
208
dw_i2c_plat_probe(struct platform_device * pdev)209 static int dw_i2c_plat_probe(struct platform_device *pdev)
210 {
211 struct device *device = &pdev->dev;
212 struct i2c_adapter *adap;
213 struct dw_i2c_dev *dev;
214 int irq, ret;
215
216 irq = platform_get_irq(pdev, 0);
217 if (irq < 0)
218 return irq;
219
220 dev = devm_kzalloc(device, sizeof(*dev), GFP_KERNEL);
221 if (!dev)
222 return -ENOMEM;
223
224 dev->flags = (uintptr_t)device_get_match_data(device);
225 if (device_property_present(device, "wx,i2c-snps-model"))
226 dev->flags = MODEL_WANGXUN_SP | ACCESS_POLLING;
227
228 dev->dev = device;
229 dev->irq = irq;
230 platform_set_drvdata(pdev, dev);
231
232 ret = dw_i2c_plat_request_regs(dev);
233 if (ret)
234 return ret;
235
236 dev->rst = devm_reset_control_get_optional_exclusive(device, NULL);
237 if (IS_ERR(dev->rst))
238 return PTR_ERR(dev->rst);
239
240 reset_control_deassert(dev->rst);
241
242 ret = i2c_dw_fw_parse_and_configure(dev);
243 if (ret)
244 goto exit_reset;
245
246 ret = i2c_dw_probe_lock_support(dev);
247 if (ret)
248 goto exit_reset;
249
250 i2c_dw_configure(dev);
251
252 /* Optional interface clock */
253 dev->pclk = devm_clk_get_optional(device, "pclk");
254 if (IS_ERR(dev->pclk)) {
255 ret = PTR_ERR(dev->pclk);
256 goto exit_reset;
257 }
258
259 dev->clk = devm_clk_get_optional(device, NULL);
260 if (IS_ERR(dev->clk)) {
261 ret = PTR_ERR(dev->clk);
262 goto exit_reset;
263 }
264
265 ret = i2c_dw_prepare_clk(dev, true);
266 if (ret)
267 goto exit_reset;
268
269 if (dev->clk) {
270 struct i2c_timings *t = &dev->timings;
271 u64 clk_khz;
272
273 dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
274 clk_khz = dev->get_clk_rate_khz(dev);
275
276 if (!dev->sda_hold_time && t->sda_hold_ns)
277 dev->sda_hold_time =
278 DIV_S64_ROUND_CLOSEST(clk_khz * t->sda_hold_ns, MICRO);
279 }
280
281 adap = &dev->adapter;
282 adap->owner = THIS_MODULE;
283 adap->class = dmi_check_system(dw_i2c_hwmon_class_dmi) ?
284 I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED;
285 adap->nr = -1;
286
287 if (dev->flags & ACCESS_NO_IRQ_SUSPEND)
288 dev_pm_set_driver_flags(device, DPM_FLAG_SMART_PREPARE);
289 else
290 dev_pm_set_driver_flags(device, DPM_FLAG_SMART_PREPARE | DPM_FLAG_SMART_SUSPEND);
291
292 device_enable_async_suspend(device);
293
294 /* The code below assumes runtime PM to be disabled. */
295 WARN_ON(pm_runtime_enabled(device));
296
297 pm_runtime_set_autosuspend_delay(device, 1000);
298 pm_runtime_use_autosuspend(device);
299 pm_runtime_set_active(device);
300
301 if (dev->shared_with_punit)
302 pm_runtime_get_noresume(device);
303
304 pm_runtime_enable(device);
305
306 ret = i2c_dw_probe(dev);
307 if (ret)
308 goto exit_probe;
309
310 return ret;
311
312 exit_probe:
313 dw_i2c_plat_pm_cleanup(dev);
314 exit_reset:
315 reset_control_assert(dev->rst);
316 return ret;
317 }
318
dw_i2c_plat_remove(struct platform_device * pdev)319 static void dw_i2c_plat_remove(struct platform_device *pdev)
320 {
321 struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
322 struct device *device = &pdev->dev;
323
324 pm_runtime_get_sync(device);
325
326 i2c_del_adapter(&dev->adapter);
327
328 i2c_dw_disable(dev);
329
330 pm_runtime_dont_use_autosuspend(device);
331 pm_runtime_put_sync(device);
332 dw_i2c_plat_pm_cleanup(dev);
333
334 i2c_dw_remove_lock_support(dev);
335
336 reset_control_assert(dev->rst);
337 }
338
339 static const struct of_device_id dw_i2c_of_match[] = {
340 { .compatible = "snps,designware-i2c", },
341 { .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
342 { .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 },
343 {}
344 };
345 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
346
347 static const struct acpi_device_id dw_i2c_acpi_match[] = {
348 { "80860F41", ACCESS_NO_IRQ_SUSPEND },
349 { "808622C1", ACCESS_NO_IRQ_SUSPEND },
350 { "AMD0010", ACCESS_INTR_MASK },
351 { "AMDI0010", ACCESS_INTR_MASK },
352 { "AMDI0019", ACCESS_INTR_MASK | ARBITRATION_SEMAPHORE },
353 { "AMDI0510", 0 },
354 { "APMC0D0F", 0 },
355 { "HISI02A1", 0 },
356 { "HISI02A2", 0 },
357 { "HISI02A3", 0 },
358 { "HYGO0010", ACCESS_INTR_MASK },
359 { "INT33C2", 0 },
360 { "INT33C3", 0 },
361 { "INT3432", 0 },
362 { "INT3433", 0 },
363 { "INTC10EF", 0 },
364 {}
365 };
366 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
367
368 static const struct platform_device_id dw_i2c_platform_ids[] = {
369 { "i2c_designware" },
370 {}
371 };
372 MODULE_DEVICE_TABLE(platform, dw_i2c_platform_ids);
373
374 static struct platform_driver dw_i2c_driver = {
375 .probe = dw_i2c_plat_probe,
376 .remove_new = dw_i2c_plat_remove,
377 .driver = {
378 .name = "i2c_designware",
379 .of_match_table = dw_i2c_of_match,
380 .acpi_match_table = dw_i2c_acpi_match,
381 .pm = pm_ptr(&i2c_dw_dev_pm_ops),
382 },
383 .id_table = dw_i2c_platform_ids,
384 };
385
dw_i2c_init_driver(void)386 static int __init dw_i2c_init_driver(void)
387 {
388 return platform_driver_register(&dw_i2c_driver);
389 }
390 subsys_initcall(dw_i2c_init_driver);
391
dw_i2c_exit_driver(void)392 static void __exit dw_i2c_exit_driver(void)
393 {
394 platform_driver_unregister(&dw_i2c_driver);
395 }
396 module_exit(dw_i2c_exit_driver);
397
398 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
399 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
400 MODULE_LICENSE("GPL");
401 MODULE_IMPORT_NS(I2C_DW);
402 MODULE_IMPORT_NS(I2C_DW_COMMON);
403