xref: /linux/drivers/platform/x86/serial-multi-instantiate.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Serial multi-instantiate driver, pseudo driver to instantiate multiple
4  * client devices from a single fwnode.
5  *
6  * Copyright 2018 Hans de Goede <hdegoede@redhat.com>
7  */
8 
9 #include <linux/acpi.h>
10 #include <linux/bits.h>
11 #include <linux/i2c.h>
12 #include <linux/interrupt.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/platform_device.h>
16 #include <linux/property.h>
17 #include <linux/spi/spi.h>
18 #include <linux/types.h>
19 
20 #define IRQ_RESOURCE_TYPE	GENMASK(1, 0)
21 #define IRQ_RESOURCE_NONE	0
22 #define IRQ_RESOURCE_GPIO	1
23 #define IRQ_RESOURCE_APIC	2
24 #define IRQ_RESOURCE_AUTO   3
25 
26 enum smi_bus_type {
27 	SMI_I2C,
28 	SMI_SPI,
29 	SMI_AUTO_DETECT,
30 };
31 
32 struct smi_instance {
33 	const char *type;
34 	unsigned int flags;
35 	int irq_idx;
36 };
37 
38 struct smi_node {
39 	enum smi_bus_type bus_type;
40 	struct smi_instance instances[];
41 };
42 
43 struct smi {
44 	int i2c_num;
45 	int spi_num;
46 	struct i2c_client **i2c_devs;
47 	struct spi_device **spi_devs;
48 };
49 
50 static int smi_get_irq(struct platform_device *pdev, struct acpi_device *adev,
51 		       const struct smi_instance *inst)
52 {
53 	int ret;
54 
55 	switch (inst->flags & IRQ_RESOURCE_TYPE) {
56 	case IRQ_RESOURCE_AUTO:
57 		ret = acpi_dev_gpio_irq_get(adev, inst->irq_idx);
58 		if (ret > 0) {
59 			dev_dbg(&pdev->dev, "Using gpio irq\n");
60 			break;
61 		}
62 		ret = platform_get_irq(pdev, inst->irq_idx);
63 		if (ret > 0) {
64 			dev_dbg(&pdev->dev, "Using platform irq\n");
65 			break;
66 		}
67 		break;
68 	case IRQ_RESOURCE_GPIO:
69 		ret = acpi_dev_gpio_irq_get(adev, inst->irq_idx);
70 		break;
71 	case IRQ_RESOURCE_APIC:
72 		ret = platform_get_irq(pdev, inst->irq_idx);
73 		break;
74 	default:
75 		return 0;
76 	}
77 	if (ret < 0)
78 		return dev_err_probe(&pdev->dev, ret, "Error requesting irq at index %d\n",
79 				     inst->irq_idx);
80 
81 	return ret;
82 }
83 
84 static void smi_devs_unregister(struct smi *smi)
85 {
86 #if IS_REACHABLE(CONFIG_I2C)
87 	while (smi->i2c_num--)
88 		i2c_unregister_device(smi->i2c_devs[smi->i2c_num]);
89 #endif
90 
91 	if (IS_REACHABLE(CONFIG_SPI)) {
92 		while (smi->spi_num--)
93 			spi_unregister_device(smi->spi_devs[smi->spi_num]);
94 	}
95 }
96 
97 /**
98  * smi_spi_probe - Instantiate multiple SPI devices from inst array
99  * @pdev:	Platform device
100  * @smi:	Internal struct for Serial multi instantiate driver
101  * @inst_array:	Array of instances to probe
102  *
103  * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
104  */
105 static int smi_spi_probe(struct platform_device *pdev, struct smi *smi,
106 			 const struct smi_instance *inst_array)
107 {
108 	struct device *dev = &pdev->dev;
109 	struct acpi_device *adev = ACPI_COMPANION(dev);
110 	struct spi_controller *ctlr;
111 	struct spi_device *spi_dev;
112 	char name[50];
113 	int i, ret, count;
114 
115 	ret = acpi_spi_count_resources(adev);
116 	if (ret < 0)
117 		return ret;
118 	if (!ret)
119 		return -ENOENT;
120 
121 	count = ret;
122 
123 	smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
124 	if (!smi->spi_devs)
125 		return -ENOMEM;
126 
127 	for (i = 0; i < count && inst_array[i].type; i++) {
128 
129 		spi_dev = acpi_spi_device_alloc(NULL, adev, i);
130 		if (IS_ERR(spi_dev)) {
131 			ret = dev_err_probe(dev, PTR_ERR(spi_dev), "failed to allocate SPI device %s from ACPI\n",
132 					    dev_name(&adev->dev));
133 			goto error;
134 		}
135 
136 		ctlr = spi_dev->controller;
137 
138 		strscpy(spi_dev->modalias, inst_array[i].type);
139 
140 		ret = smi_get_irq(pdev, adev, &inst_array[i]);
141 		if (ret < 0) {
142 			spi_dev_put(spi_dev);
143 			goto error;
144 		}
145 		spi_dev->irq = ret;
146 
147 		snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
148 			 inst_array[i].type, i);
149 		spi_dev->dev.init_name = name;
150 
151 		ret = spi_add_device(spi_dev);
152 		if (ret) {
153 			dev_err_probe(&ctlr->dev, ret, "failed to add SPI device %s from ACPI\n",
154 				      dev_name(&adev->dev));
155 			spi_dev_put(spi_dev);
156 			goto error;
157 		}
158 
159 		dev_dbg(dev, "SPI device %s using chip select %u", name,
160 			spi_get_chipselect(spi_dev, 0));
161 
162 		smi->spi_devs[i] = spi_dev;
163 		smi->spi_num++;
164 	}
165 
166 	if (smi->spi_num < count) {
167 		dev_dbg(dev, "Error finding driver, idx %d\n", i);
168 		ret = -ENODEV;
169 		goto error;
170 	}
171 
172 	dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);
173 
174 	return 0;
175 error:
176 	smi_devs_unregister(smi);
177 
178 	return ret;
179 }
180 
181 /**
182  * smi_i2c_probe - Instantiate multiple I2C devices from inst array
183  * @pdev:	Platform device
184  * @smi:	Internal struct for Serial multi instantiate driver
185  * @inst_array:	Array of instances to probe
186  *
187  * Returns the number of I2C devices instantiate, Zero if none is found or a negative error code.
188  */
189 static int smi_i2c_probe(struct platform_device *pdev, struct smi *smi,
190 			 const struct smi_instance *inst_array)
191 {
192 	struct i2c_board_info board_info = {};
193 	struct device *dev = &pdev->dev;
194 	struct acpi_device *adev = ACPI_COMPANION(dev);
195 	char name[32];
196 	int i, ret, count;
197 
198 	ret = i2c_acpi_client_count(adev);
199 	if (ret < 0)
200 		return ret;
201 	if (!ret)
202 		return -ENOENT;
203 
204 	count = ret;
205 
206 	smi->i2c_devs = devm_kcalloc(dev, count, sizeof(*smi->i2c_devs), GFP_KERNEL);
207 	if (!smi->i2c_devs)
208 		return -ENOMEM;
209 
210 	for (i = 0; i < count && inst_array[i].type; i++) {
211 		memset(&board_info, 0, sizeof(board_info));
212 		strscpy(board_info.type, inst_array[i].type);
213 		snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev), inst_array[i].type, i);
214 		board_info.dev_name = name;
215 
216 		ret = smi_get_irq(pdev, adev, &inst_array[i]);
217 		if (ret < 0)
218 			goto error;
219 		board_info.irq = ret;
220 
221 		smi->i2c_devs[i] = i2c_acpi_new_device(dev, i, &board_info);
222 		if (IS_ERR(smi->i2c_devs[i])) {
223 			ret = dev_err_probe(dev, PTR_ERR(smi->i2c_devs[i]),
224 					    "Error creating i2c-client, idx %d\n", i);
225 			goto error;
226 		}
227 		smi->i2c_num++;
228 	}
229 	if (smi->i2c_num < count) {
230 		dev_dbg(dev, "Error finding driver, idx %d\n", i);
231 		ret = -ENODEV;
232 		goto error;
233 	}
234 
235 	dev_info(dev, "Instantiated %d I2C devices.\n", smi->i2c_num);
236 
237 	return 0;
238 error:
239 	smi_devs_unregister(smi);
240 
241 	return ret;
242 }
243 
244 static int smi_probe(struct platform_device *pdev)
245 {
246 	struct device *dev = &pdev->dev;
247 	const struct smi_node *node;
248 	struct smi *smi;
249 	int ret;
250 
251 	node = device_get_match_data(dev);
252 	if (!node) {
253 		dev_dbg(dev, "Error ACPI match data is missing\n");
254 		return -ENODEV;
255 	}
256 
257 	smi = devm_kzalloc(dev, sizeof(*smi), GFP_KERNEL);
258 	if (!smi)
259 		return -ENOMEM;
260 
261 	platform_set_drvdata(pdev, smi);
262 
263 	switch (node->bus_type) {
264 	case SMI_I2C:
265 		if (IS_REACHABLE(CONFIG_I2C))
266 			return smi_i2c_probe(pdev, smi, node->instances);
267 
268 		return -ENODEV;
269 	case SMI_SPI:
270 		if (IS_REACHABLE(CONFIG_SPI))
271 			return smi_spi_probe(pdev, smi, node->instances);
272 
273 		return -ENODEV;
274 	case SMI_AUTO_DETECT:
275 		/*
276 		 * For backwards-compatibility with the existing nodes I2C
277 		 * is checked first and if such entries are found ONLY I2C
278 		 * devices are created. Since some existing nodes that were
279 		 * already handled by this driver could also contain unrelated
280 		 * SpiSerialBus nodes that were previously ignored, and this
281 		 * preserves that behavior.
282 		 */
283 		if (IS_REACHABLE(CONFIG_I2C)) {
284 			ret = smi_i2c_probe(pdev, smi, node->instances);
285 			if (ret != -ENOENT)
286 				return ret;
287 		}
288 
289 		if (IS_REACHABLE(CONFIG_SPI))
290 			return smi_spi_probe(pdev, smi, node->instances);
291 
292 		return -ENODEV;
293 	default:
294 		return -EINVAL;
295 	}
296 }
297 
298 static void smi_remove(struct platform_device *pdev)
299 {
300 	struct smi *smi = platform_get_drvdata(pdev);
301 
302 	smi_devs_unregister(smi);
303 }
304 
305 static const struct smi_node bsg1160_data = {
306 	.instances = {
307 		{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
308 		{ "bmc150_magn" },
309 		{ "bmg160" },
310 		{}
311 	},
312 	.bus_type = SMI_I2C,
313 };
314 
315 static const struct smi_node bsg2150_data = {
316 	.instances = {
317 		{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
318 		{ "bmc150_magn" },
319 		/* The resources describe a 3th client, but it is not really there. */
320 		{ "bsg2150_dummy_dev" },
321 		{}
322 	},
323 	.bus_type = SMI_I2C,
324 };
325 
326 static const struct smi_node int3515_data = {
327 	.instances = {
328 		{ "tps6598x", IRQ_RESOURCE_APIC, 0 },
329 		{ "tps6598x", IRQ_RESOURCE_APIC, 1 },
330 		{ "tps6598x", IRQ_RESOURCE_APIC, 2 },
331 		{ "tps6598x", IRQ_RESOURCE_APIC, 3 },
332 		{}
333 	},
334 	.bus_type = SMI_I2C,
335 };
336 
337 static const struct smi_node cs35l41_hda = {
338 	.instances = {
339 		{ "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
340 		{ "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
341 		{ "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
342 		{ "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
343 		{}
344 	},
345 	.bus_type = SMI_AUTO_DETECT,
346 };
347 
348 static const struct smi_node cs35l54_hda = {
349 	.instances = {
350 		{ "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
351 		{ "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
352 		{ "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
353 		{ "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
354 		/* a 5th entry is an alias address, not a real device */
355 		{ "cs35l54-hda_dummy_dev" },
356 		{}
357 	},
358 	.bus_type = SMI_AUTO_DETECT,
359 };
360 
361 static const struct smi_node cs35l56_hda = {
362 	.instances = {
363 		{ "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
364 		{ "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
365 		{ "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
366 		{ "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
367 		/* a 5th entry is an alias address, not a real device */
368 		{ "cs35l56-hda_dummy_dev" },
369 		{}
370 	},
371 	.bus_type = SMI_AUTO_DETECT,
372 };
373 
374 static const struct smi_node cs35l57_hda = {
375 	.instances = {
376 		{ "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
377 		{ "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
378 		{ "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
379 		{ "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
380 		/* a 5th entry is an alias address, not a real device */
381 		{ "cs35l57-hda_dummy_dev" },
382 		{}
383 	},
384 	.bus_type = SMI_AUTO_DETECT,
385 };
386 
387 /*
388  * Note new device-ids must also be added to ignore_serial_bus_ids in
389  * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
390  */
391 static const struct acpi_device_id smi_acpi_ids[] = {
392 	{ "BSG1160", (unsigned long)&bsg1160_data },
393 	{ "BSG2150", (unsigned long)&bsg2150_data },
394 	{ "CSC3551", (unsigned long)&cs35l41_hda },
395 	{ "CSC3554", (unsigned long)&cs35l54_hda },
396 	{ "CSC3556", (unsigned long)&cs35l56_hda },
397 	{ "CSC3557", (unsigned long)&cs35l57_hda },
398 	{ "INT3515", (unsigned long)&int3515_data },
399 	/* Non-conforming _HID for Cirrus Logic already released */
400 	{ "CLSA0100", (unsigned long)&cs35l41_hda },
401 	{ "CLSA0101", (unsigned long)&cs35l41_hda },
402 	{ }
403 };
404 MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);
405 
406 static struct platform_driver smi_driver = {
407 	.driver	= {
408 		.name = "Serial bus multi instantiate pseudo device driver",
409 		.acpi_match_table = smi_acpi_ids,
410 	},
411 	.probe = smi_probe,
412 	.remove_new = smi_remove,
413 };
414 module_platform_driver(smi_driver);
415 
416 MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
417 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
418 MODULE_LICENSE("GPL");
419