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
smi_get_irq(struct platform_device * pdev,struct acpi_device * adev,const struct smi_instance * inst)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
smi_devs_unregister(struct smi * smi)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 */
smi_spi_probe(struct platform_device * pdev,struct smi * smi,const struct smi_instance * inst_array)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 */
smi_i2c_probe(struct platform_device * pdev,struct smi * smi,const struct smi_instance * inst_array)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
smi_probe(struct platform_device * pdev)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
smi_remove(struct platform_device * pdev)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 = 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