xref: /linux/drivers/i2c/busses/i2c-designware-platdrv.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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) / 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 
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 txgbe_i2c_request_regs(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 	switch (dev->flags & MODEL_MASK) {
127 	case MODEL_BAIKAL_BT1:
128 		ret = bt1_i2c_request_regs(dev);
129 		break;
130 	case MODEL_WANGXUN_SP:
131 		ret = txgbe_i2c_request_regs(dev);
132 		break;
133 	default:
134 		dev->base = devm_platform_ioremap_resource(pdev, 0);
135 		ret = PTR_ERR_OR_ZERO(dev->base);
136 		break;
137 	}
138 
139 	return ret;
140 }
141 
142 static const struct dmi_system_id dw_i2c_hwmon_class_dmi[] = {
143 	{
144 		.ident = "Qtechnology QT5222",
145 		.matches = {
146 			DMI_MATCH(DMI_SYS_VENDOR, "Qtechnology"),
147 			DMI_MATCH(DMI_PRODUCT_NAME, "QT5222"),
148 		},
149 	},
150 	{ } /* terminate list */
151 };
152 
153 static const struct i2c_dw_semaphore_callbacks i2c_dw_semaphore_cb_table[] = {
154 #ifdef CONFIG_I2C_DESIGNWARE_BAYTRAIL
155 	{
156 		.probe = i2c_dw_baytrail_probe_lock_support,
157 	},
158 #endif
159 #ifdef CONFIG_I2C_DESIGNWARE_AMDPSP
160 	{
161 		.probe = i2c_dw_amdpsp_probe_lock_support,
162 	},
163 #endif
164 	{}
165 };
166 
167 static int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev)
168 {
169 	const struct i2c_dw_semaphore_callbacks *ptr;
170 	int i = 0;
171 	int ret;
172 
173 	dev->semaphore_idx = -1;
174 
175 	for (ptr = i2c_dw_semaphore_cb_table; ptr->probe; ptr++) {
176 		ret = ptr->probe(dev);
177 		if (ret) {
178 			/*
179 			 * If there is no semaphore device attached to this
180 			 * controller, we shouldn't abort general i2c_controller
181 			 * probe.
182 			 */
183 			if (ret != -ENODEV)
184 				return ret;
185 
186 			i++;
187 			continue;
188 		}
189 
190 		dev->semaphore_idx = i;
191 		break;
192 	}
193 
194 	return 0;
195 }
196 
197 static void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev)
198 {
199 	if (dev->semaphore_idx < 0)
200 		return;
201 
202 	if (i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove)
203 		i2c_dw_semaphore_cb_table[dev->semaphore_idx].remove(dev);
204 }
205 
206 static int dw_i2c_plat_probe(struct platform_device *pdev)
207 {
208 	struct device *device = &pdev->dev;
209 	struct i2c_adapter *adap;
210 	struct dw_i2c_dev *dev;
211 	int irq, ret;
212 
213 	irq = platform_get_irq(pdev, 0);
214 	if (irq < 0)
215 		return irq;
216 
217 	dev = devm_kzalloc(device, sizeof(*dev), GFP_KERNEL);
218 	if (!dev)
219 		return -ENOMEM;
220 
221 	dev->flags = (uintptr_t)device_get_match_data(device);
222 	if (device_property_present(device, "wx,i2c-snps-model"))
223 		dev->flags = MODEL_WANGXUN_SP | ACCESS_POLLING;
224 
225 	dev->dev = device;
226 	dev->irq = irq;
227 	platform_set_drvdata(pdev, dev);
228 
229 	ret = dw_i2c_plat_request_regs(dev);
230 	if (ret)
231 		return ret;
232 
233 	dev->rst = devm_reset_control_get_optional_exclusive(device, NULL);
234 	if (IS_ERR(dev->rst))
235 		return PTR_ERR(dev->rst);
236 
237 	reset_control_deassert(dev->rst);
238 
239 	ret = i2c_dw_fw_parse_and_configure(dev);
240 	if (ret)
241 		goto exit_reset;
242 
243 	ret = i2c_dw_probe_lock_support(dev);
244 	if (ret)
245 		goto exit_reset;
246 
247 	i2c_dw_configure(dev);
248 
249 	/* Optional interface clock */
250 	dev->pclk = devm_clk_get_optional(device, "pclk");
251 	if (IS_ERR(dev->pclk)) {
252 		ret = PTR_ERR(dev->pclk);
253 		goto exit_reset;
254 	}
255 
256 	dev->clk = devm_clk_get_optional(device, NULL);
257 	if (IS_ERR(dev->clk)) {
258 		ret = PTR_ERR(dev->clk);
259 		goto exit_reset;
260 	}
261 
262 	ret = i2c_dw_prepare_clk(dev, true);
263 	if (ret)
264 		goto exit_reset;
265 
266 	if (dev->clk) {
267 		struct i2c_timings *t = &dev->timings;
268 		u64 clk_khz;
269 
270 		dev->get_clk_rate_khz = i2c_dw_get_clk_rate_khz;
271 		clk_khz = dev->get_clk_rate_khz(dev);
272 
273 		if (!dev->sda_hold_time && t->sda_hold_ns)
274 			dev->sda_hold_time =
275 				DIV_S64_ROUND_CLOSEST(clk_khz * t->sda_hold_ns, MICRO);
276 	}
277 
278 	adap = &dev->adapter;
279 	adap->owner = THIS_MODULE;
280 	adap->class = dmi_check_system(dw_i2c_hwmon_class_dmi) ?
281 				       I2C_CLASS_HWMON : I2C_CLASS_DEPRECATED;
282 	adap->nr = -1;
283 
284 	if (dev->flags & ACCESS_NO_IRQ_SUSPEND)
285 		dev_pm_set_driver_flags(device, DPM_FLAG_SMART_PREPARE);
286 	else
287 		dev_pm_set_driver_flags(device, DPM_FLAG_SMART_PREPARE | DPM_FLAG_SMART_SUSPEND);
288 
289 	device_enable_async_suspend(device);
290 
291 	/* The code below assumes runtime PM to be disabled. */
292 	WARN_ON(pm_runtime_enabled(device));
293 
294 	pm_runtime_set_autosuspend_delay(device, 1000);
295 	pm_runtime_use_autosuspend(device);
296 	pm_runtime_set_active(device);
297 
298 	if (dev->shared_with_punit)
299 		pm_runtime_get_noresume(device);
300 
301 	pm_runtime_enable(device);
302 
303 	ret = i2c_dw_probe(dev);
304 	if (ret)
305 		goto exit_probe;
306 
307 	return ret;
308 
309 exit_probe:
310 	dw_i2c_plat_pm_cleanup(dev);
311 exit_reset:
312 	reset_control_assert(dev->rst);
313 	return ret;
314 }
315 
316 static void dw_i2c_plat_remove(struct platform_device *pdev)
317 {
318 	struct dw_i2c_dev *dev = platform_get_drvdata(pdev);
319 	struct device *device = &pdev->dev;
320 
321 	pm_runtime_get_sync(device);
322 
323 	i2c_del_adapter(&dev->adapter);
324 
325 	i2c_dw_disable(dev);
326 
327 	pm_runtime_dont_use_autosuspend(device);
328 	pm_runtime_put_sync(device);
329 	dw_i2c_plat_pm_cleanup(dev);
330 
331 	i2c_dw_remove_lock_support(dev);
332 
333 	reset_control_assert(dev->rst);
334 }
335 
336 static const struct of_device_id dw_i2c_of_match[] = {
337 	{ .compatible = "snps,designware-i2c", },
338 	{ .compatible = "mscc,ocelot-i2c", .data = (void *)MODEL_MSCC_OCELOT },
339 	{ .compatible = "baikal,bt1-sys-i2c", .data = (void *)MODEL_BAIKAL_BT1 },
340 	{}
341 };
342 MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
343 
344 static const struct acpi_device_id dw_i2c_acpi_match[] = {
345 	{ "80860F41", ACCESS_NO_IRQ_SUSPEND },
346 	{ "808622C1", ACCESS_NO_IRQ_SUSPEND },
347 	{ "AMD0010", ACCESS_INTR_MASK },
348 	{ "AMDI0010", ACCESS_INTR_MASK },
349 	{ "AMDI0019", ACCESS_INTR_MASK | ARBITRATION_SEMAPHORE },
350 	{ "AMDI0510", 0 },
351 	{ "APMC0D0F", 0 },
352 	{ "FUJI200B", 0 },
353 	{ "HISI02A1", 0 },
354 	{ "HISI02A2", 0 },
355 	{ "HISI02A3", 0 },
356 	{ "HJMC3001", 0 },
357 	{ "HYGO0010", ACCESS_INTR_MASK },
358 	{ "INT33C2", 0 },
359 	{ "INT33C3", 0 },
360 	{ "INT3432", 0 },
361 	{ "INT3433", 0 },
362 	{ "INTC10EF", 0 },
363 	{}
364 };
365 MODULE_DEVICE_TABLE(acpi, dw_i2c_acpi_match);
366 
367 static const struct platform_device_id dw_i2c_platform_ids[] = {
368 	{ "i2c_designware" },
369 	{}
370 };
371 MODULE_DEVICE_TABLE(platform, dw_i2c_platform_ids);
372 
373 static struct platform_driver dw_i2c_driver = {
374 	.probe = dw_i2c_plat_probe,
375 	.remove = dw_i2c_plat_remove,
376 	.driver		= {
377 		.name	= "i2c_designware",
378 		.of_match_table = dw_i2c_of_match,
379 		.acpi_match_table = dw_i2c_acpi_match,
380 		.pm	= pm_ptr(&i2c_dw_dev_pm_ops),
381 	},
382 	.id_table = dw_i2c_platform_ids,
383 };
384 
385 static int __init dw_i2c_init_driver(void)
386 {
387 	return platform_driver_register(&dw_i2c_driver);
388 }
389 subsys_initcall(dw_i2c_init_driver);
390 
391 static void __exit dw_i2c_exit_driver(void)
392 {
393 	platform_driver_unregister(&dw_i2c_driver);
394 }
395 module_exit(dw_i2c_exit_driver);
396 
397 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
398 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
399 MODULE_LICENSE("GPL");
400 MODULE_IMPORT_NS(I2C_DW);
401 MODULE_IMPORT_NS(I2C_DW_COMMON);
402