xref: /linux/drivers/i2c/busses/i2c-designware-platdrv.c (revision b4ada0618eed0fbd1b1630f73deb048c592b06a1)
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 
35 static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev)
36 {
37 	return clk_get_rate(dev->clk) / HZ_PER_KHZ;
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 
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 
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 
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
98 static int bt1_i2c_request_regs(struct dw_i2c_dev *dev)
99 {
100 	return -ENODEV;
101 }
102 #endif
103 
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 
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 
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 
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 
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 
209 static int dw_i2c_plat_probe(struct platform_device *pdev)
210 {
211 	u32 flags = (uintptr_t)device_get_match_data(&pdev->dev);
212 	struct device *device = &pdev->dev;
213 	struct i2c_adapter *adap;
214 	struct dw_i2c_dev *dev;
215 	int irq, ret;
216 
217 	irq = platform_get_irq_optional(pdev, 0);
218 	if (irq == -ENXIO)
219 		flags |= ACCESS_POLLING;
220 	else if (irq < 0)
221 		return irq;
222 
223 	dev = devm_kzalloc(device, sizeof(*dev), GFP_KERNEL);
224 	if (!dev)
225 		return -ENOMEM;
226 
227 	if (device_property_present(device, "wx,i2c-snps-model"))
228 		flags = MODEL_WANGXUN_SP | ACCESS_POLLING;
229 
230 	dev->dev = device;
231 	dev->irq = irq;
232 	dev->flags = flags;
233 	platform_set_drvdata(pdev, dev);
234 
235 	ret = dw_i2c_plat_request_regs(dev);
236 	if (ret)
237 		return ret;
238 
239 	dev->rst = devm_reset_control_get_optional_exclusive(device, NULL);
240 	if (IS_ERR(dev->rst))
241 		return PTR_ERR(dev->rst);
242 
243 	reset_control_deassert(dev->rst);
244 
245 	ret = i2c_dw_fw_parse_and_configure(dev);
246 	if (ret)
247 		goto exit_reset;
248 
249 	ret = i2c_dw_probe_lock_support(dev);
250 	if (ret)
251 		goto exit_reset;
252 
253 	i2c_dw_configure(dev);
254 
255 	/* Optional interface clock */
256 	dev->pclk = devm_clk_get_optional(device, "pclk");
257 	if (IS_ERR(dev->pclk)) {
258 		ret = PTR_ERR(dev->pclk);
259 		goto exit_reset;
260 	}
261 
262 	dev->clk = devm_clk_get_optional(device, NULL);
263 	if (IS_ERR(dev->clk)) {
264 		ret = PTR_ERR(dev->clk);
265 		goto exit_reset;
266 	}
267 
268 	ret = i2c_dw_prepare_clk(dev, true);
269 	if (ret)
270 		goto exit_reset;
271 
272 	if (dev->clk) {
273 		struct i2c_timings *t = &dev->timings;
274 		u64 clk_khz;
275 
276 		dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
277 		clk_khz = dev->get_clk_rate_khz(dev);
278 
279 		if (!dev->sda_hold_time && t->sda_hold_ns)
280 			dev->sda_hold_time =
281 				DIV_S64_ROUND_CLOSEST(clk_khz * t->sda_hold_ns, MICRO);
282 	}
283 
284 	adap = &dev->adapter;
285 	adap->owner = THIS_MODULE;
286 	adap->class = dmi_check_system(dw_i2c_hwmon_class_dmi) ?
287 				       I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED;
288 	adap->nr = -1;
289 
290 	if (dev->flags & ACCESS_NO_IRQ_SUSPEND)
291 		dev_pm_set_driver_flags(device, DPM_FLAG_SMART_PREPARE);
292 	else
293 		dev_pm_set_driver_flags(device, DPM_FLAG_SMART_PREPARE | DPM_FLAG_SMART_SUSPEND);
294 
295 	device_enable_async_suspend(device);
296 
297 	/* The code below assumes runtime PM to be disabled. */
298 	WARN_ON(pm_runtime_enabled(device));
299 
300 	pm_runtime_set_autosuspend_delay(device, 1000);
301 	pm_runtime_use_autosuspend(device);
302 	pm_runtime_set_active(device);
303 
304 	if (dev->shared_with_punit)
305 		pm_runtime_get_noresume(device);
306 
307 	pm_runtime_enable(device);
308 
309 	ret = i2c_dw_probe(dev);
310 	if (ret)
311 		goto exit_probe;
312 
313 	return ret;
314 
315 exit_probe:
316 	dw_i2c_plat_pm_cleanup(dev);
317 exit_reset:
318 	reset_control_assert(dev->rst);
319 	return ret;
320 }
321 
322 static void dw_i2c_plat_remove(struct platform_device *pdev)
323 {
324 	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
325 	struct device *device = &pdev->dev;
326 
327 	pm_runtime_get_sync(device);
328 
329 	i2c_del_adapter(&dev->adapter);
330 
331 	i2c_dw_disable(dev);
332 
333 	pm_runtime_dont_use_autosuspend(device);
334 	pm_runtime_put_sync(device);
335 	dw_i2c_plat_pm_cleanup(dev);
336 
337 	i2c_dw_remove_lock_support(dev);
338 
339 	reset_control_assert(dev->rst);
340 }
341 
342 static const struct of_device_id dw_i2c_of_match[] = {
343 	{ .compatible = "snps,designware-i2c", },
344 	{ .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
345 	{ .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 },
346 	{}
347 };
348 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
349 
350 static const struct acpi_device_id dw_i2c_acpi_match[] = {
351 	{ "80860F41", ACCESS_NO_IRQ_SUSPEND },
352 	{ "808622C1", ACCESS_NO_IRQ_SUSPEND },
353 	{ "AMD0010", ACCESS_INTR_MASK },
354 	{ "AMDI0010", ACCESS_INTR_MASK },
355 	{ "AMDI0019", ACCESS_INTR_MASK | ARBITRATION_SEMAPHORE },
356 	{ "AMDI0510", 0 },
357 	{ "APMC0D0F", 0 },
358 	{ "FUJI200B", 0 },
359 	{ "HISI02A1", 0 },
360 	{ "HISI02A2", 0 },
361 	{ "HISI02A3", 0 },
362 	{ "HJMC3001", 0 },
363 	{ "HYGO0010", ACCESS_INTR_MASK },
364 	{ "INT33C2", 0 },
365 	{ "INT33C3", 0 },
366 	{ "INT3432", 0 },
367 	{ "INT3433", 0 },
368 	{ "INTC10EF", 0 },
369 	{}
370 };
371 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
372 
373 static const struct platform_device_id dw_i2c_platform_ids[] = {
374 	{ "i2c_designware" },
375 	{}
376 };
377 MODULE_DEVICE_TABLE(platform, dw_i2c_platform_ids);
378 
379 static struct platform_driver dw_i2c_driver = {
380 	.probe = dw_i2c_plat_probe,
381 	.remove = dw_i2c_plat_remove,
382 	.driver		= {
383 		.name	= "i2c_designware",
384 		.of_match_table = dw_i2c_of_match,
385 		.acpi_match_table = dw_i2c_acpi_match,
386 		.pm	= pm_ptr(&i2c_dw_dev_pm_ops),
387 	},
388 	.id_table = dw_i2c_platform_ids,
389 };
390 
391 static int __init dw_i2c_init_driver(void)
392 {
393 	return platform_driver_register(&dw_i2c_driver);
394 }
395 subsys_initcall(dw_i2c_init_driver);
396 
397 static void __exit dw_i2c_exit_driver(void)
398 {
399 	platform_driver_unregister(&dw_i2c_driver);
400 }
401 module_exit(dw_i2c_exit_driver);
402 
403 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
404 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
405 MODULE_LICENSE("GPL");
406 MODULE_IMPORT_NS("I2C_DW");
407 MODULE_IMPORT_NS("I2C_DW_COMMON");
408