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 while (smi->i2c_num--)
87 i2c_unregister_device(smi->i2c_devs[smi->i2c_num]);
88
89 while (smi->spi_num--)
90 spi_unregister_device(smi->spi_devs[smi->spi_num]);
91 }
92
93 /**
94 * smi_spi_probe - Instantiate multiple SPI devices from inst array
95 * @pdev: Platform device
96 * @smi: Internal struct for Serial multi instantiate driver
97 * @inst_array: Array of instances to probe
98 *
99 * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
100 */
smi_spi_probe(struct platform_device * pdev,struct smi * smi,const struct smi_instance * inst_array)101 static int smi_spi_probe(struct platform_device *pdev, struct smi *smi,
102 const struct smi_instance *inst_array)
103 {
104 struct device *dev = &pdev->dev;
105 struct acpi_device *adev = ACPI_COMPANION(dev);
106 struct spi_controller *ctlr;
107 struct spi_device *spi_dev;
108 char name[50];
109 int i, ret, count;
110
111 ret = acpi_spi_count_resources(adev);
112 if (ret < 0)
113 return ret;
114 if (!ret)
115 return -ENOENT;
116
117 count = ret;
118
119 smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
120 if (!smi->spi_devs)
121 return -ENOMEM;
122
123 for (i = 0; i < count && inst_array[i].type; i++) {
124
125 spi_dev = acpi_spi_device_alloc(NULL, adev, i);
126 if (IS_ERR(spi_dev)) {
127 ret = dev_err_probe(dev, PTR_ERR(spi_dev), "failed to allocate SPI device %s from ACPI\n",
128 dev_name(&adev->dev));
129 goto error;
130 }
131
132 ctlr = spi_dev->controller;
133
134 strscpy(spi_dev->modalias, inst_array[i].type, sizeof(spi_dev->modalias));
135
136 ret = smi_get_irq(pdev, adev, &inst_array[i]);
137 if (ret < 0) {
138 spi_dev_put(spi_dev);
139 goto error;
140 }
141 spi_dev->irq = ret;
142
143 snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
144 inst_array[i].type, i);
145 spi_dev->dev.init_name = name;
146
147 ret = spi_add_device(spi_dev);
148 if (ret) {
149 dev_err_probe(&ctlr->dev, ret, "failed to add SPI device %s from ACPI\n",
150 dev_name(&adev->dev));
151 spi_dev_put(spi_dev);
152 goto error;
153 }
154
155 dev_dbg(dev, "SPI device %s using chip select %u", name,
156 spi_get_chipselect(spi_dev, 0));
157
158 smi->spi_devs[i] = spi_dev;
159 smi->spi_num++;
160 }
161
162 if (smi->spi_num < count) {
163 dev_dbg(dev, "Error finding driver, idx %d\n", i);
164 ret = -ENODEV;
165 goto error;
166 }
167
168 dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);
169
170 return 0;
171 error:
172 smi_devs_unregister(smi);
173
174 return ret;
175 }
176
177 /**
178 * smi_i2c_probe - Instantiate multiple I2C devices from inst array
179 * @pdev: Platform device
180 * @smi: Internal struct for Serial multi instantiate driver
181 * @inst_array: Array of instances to probe
182 *
183 * Returns the number of I2C devices instantiate, Zero if none is found or a negative error code.
184 */
smi_i2c_probe(struct platform_device * pdev,struct smi * smi,const struct smi_instance * inst_array)185 static int smi_i2c_probe(struct platform_device *pdev, struct smi *smi,
186 const struct smi_instance *inst_array)
187 {
188 struct i2c_board_info board_info = {};
189 struct device *dev = &pdev->dev;
190 struct acpi_device *adev = ACPI_COMPANION(dev);
191 char name[32];
192 int i, ret, count;
193
194 ret = i2c_acpi_client_count(adev);
195 if (ret < 0)
196 return ret;
197 if (!ret)
198 return -ENOENT;
199
200 count = ret;
201
202 smi->i2c_devs = devm_kcalloc(dev, count, sizeof(*smi->i2c_devs), GFP_KERNEL);
203 if (!smi->i2c_devs)
204 return -ENOMEM;
205
206 for (i = 0; i < count && inst_array[i].type; i++) {
207 memset(&board_info, 0, sizeof(board_info));
208 strscpy(board_info.type, inst_array[i].type, I2C_NAME_SIZE);
209 snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev), inst_array[i].type, i);
210 board_info.dev_name = name;
211
212 ret = smi_get_irq(pdev, adev, &inst_array[i]);
213 if (ret < 0)
214 goto error;
215 board_info.irq = ret;
216
217 smi->i2c_devs[i] = i2c_acpi_new_device(dev, i, &board_info);
218 if (IS_ERR(smi->i2c_devs[i])) {
219 ret = dev_err_probe(dev, PTR_ERR(smi->i2c_devs[i]),
220 "Error creating i2c-client, idx %d\n", i);
221 goto error;
222 }
223 smi->i2c_num++;
224 }
225 if (smi->i2c_num < count) {
226 dev_dbg(dev, "Error finding driver, idx %d\n", i);
227 ret = -ENODEV;
228 goto error;
229 }
230
231 dev_info(dev, "Instantiated %d I2C devices.\n", smi->i2c_num);
232
233 return 0;
234 error:
235 smi_devs_unregister(smi);
236
237 return ret;
238 }
239
smi_probe(struct platform_device * pdev)240 static int smi_probe(struct platform_device *pdev)
241 {
242 struct device *dev = &pdev->dev;
243 const struct smi_node *node;
244 struct smi *smi;
245 int ret;
246
247 node = device_get_match_data(dev);
248 if (!node) {
249 dev_dbg(dev, "Error ACPI match data is missing\n");
250 return -ENODEV;
251 }
252
253 smi = devm_kzalloc(dev, sizeof(*smi), GFP_KERNEL);
254 if (!smi)
255 return -ENOMEM;
256
257 platform_set_drvdata(pdev, smi);
258
259 switch (node->bus_type) {
260 case SMI_I2C:
261 return smi_i2c_probe(pdev, smi, node->instances);
262 case SMI_SPI:
263 return smi_spi_probe(pdev, smi, node->instances);
264 case SMI_AUTO_DETECT:
265 /*
266 * For backwards-compatibility with the existing nodes I2C
267 * is checked first and if such entries are found ONLY I2C
268 * devices are created. Since some existing nodes that were
269 * already handled by this driver could also contain unrelated
270 * SpiSerialBus nodes that were previously ignored, and this
271 * preserves that behavior.
272 */
273 ret = smi_i2c_probe(pdev, smi, node->instances);
274 if (ret != -ENOENT)
275 return ret;
276 return smi_spi_probe(pdev, smi, node->instances);
277 default:
278 return -EINVAL;
279 }
280 }
281
smi_remove(struct platform_device * pdev)282 static void smi_remove(struct platform_device *pdev)
283 {
284 struct smi *smi = platform_get_drvdata(pdev);
285
286 smi_devs_unregister(smi);
287 }
288
289 static const struct smi_node bsg1160_data = {
290 .instances = {
291 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
292 { "bmc150_magn" },
293 { "bmg160" },
294 {}
295 },
296 .bus_type = SMI_I2C,
297 };
298
299 static const struct smi_node bsg2150_data = {
300 .instances = {
301 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
302 { "bmc150_magn" },
303 /* The resources describe a 3th client, but it is not really there. */
304 { "bsg2150_dummy_dev" },
305 {}
306 },
307 .bus_type = SMI_I2C,
308 };
309
310 static const struct smi_node int3515_data = {
311 .instances = {
312 { "tps6598x", IRQ_RESOURCE_APIC, 0 },
313 { "tps6598x", IRQ_RESOURCE_APIC, 1 },
314 { "tps6598x", IRQ_RESOURCE_APIC, 2 },
315 { "tps6598x", IRQ_RESOURCE_APIC, 3 },
316 {}
317 },
318 .bus_type = SMI_I2C,
319 };
320
321 static const struct smi_node cs35l41_hda = {
322 .instances = {
323 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
324 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
325 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
326 { "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
327 {}
328 },
329 .bus_type = SMI_AUTO_DETECT,
330 };
331
332 static const struct smi_node cs35l56_hda = {
333 .instances = {
334 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
335 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
336 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
337 { "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
338 /* a 5th entry is an alias address, not a real device */
339 { "cs35l56-hda_dummy_dev" },
340 {}
341 },
342 .bus_type = SMI_AUTO_DETECT,
343 };
344
345 /*
346 * Note new device-ids must also be added to ignore_serial_bus_ids in
347 * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
348 */
349 static const struct acpi_device_id smi_acpi_ids[] = {
350 { "BSG1160", (unsigned long)&bsg1160_data },
351 { "BSG2150", (unsigned long)&bsg2150_data },
352 { "CSC3551", (unsigned long)&cs35l41_hda },
353 { "CSC3556", (unsigned long)&cs35l56_hda },
354 { "INT3515", (unsigned long)&int3515_data },
355 /* Non-conforming _HID for Cirrus Logic already released */
356 { "CLSA0100", (unsigned long)&cs35l41_hda },
357 { "CLSA0101", (unsigned long)&cs35l41_hda },
358 { }
359 };
360 MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);
361
362 static struct platform_driver smi_driver = {
363 .driver = {
364 .name = "Serial bus multi instantiate pseudo device driver",
365 .acpi_match_table = smi_acpi_ids,
366 },
367 .probe = smi_probe,
368 .remove_new = smi_remove,
369 };
370 module_platform_driver(smi_driver);
371
372 MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
373 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
374 MODULE_LICENSE("GPL");
375