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
25 enum smi_bus_type {
26 SMI_I2C,
27 SMI_SPI,
28 SMI_AUTO_DETECT,
29 };
30
31 struct smi_instance {
32 const char *type;
33 unsigned int flags;
34 int irq_idx;
35 };
36
37 struct smi_node {
38 enum smi_bus_type bus_type;
39 struct smi_instance instances[];
40 };
41
42 struct smi {
43 int i2c_num;
44 int spi_num;
45 struct i2c_client **i2c_devs;
46 struct spi_device **spi_devs;
47 };
48
smi_get_irq(struct platform_device * pdev,struct acpi_device * adev,const struct smi_instance * inst)49 static int smi_get_irq(struct platform_device *pdev, struct acpi_device *adev,
50 const struct smi_instance *inst)
51 {
52 int ret;
53
54 switch (inst->flags & IRQ_RESOURCE_TYPE) {
55 case IRQ_RESOURCE_GPIO:
56 ret = acpi_dev_gpio_irq_get(adev, inst->irq_idx);
57 break;
58 case IRQ_RESOURCE_APIC:
59 ret = platform_get_irq(pdev, inst->irq_idx);
60 break;
61 default:
62 return 0;
63 }
64
65 if (ret < 0)
66 dev_err_probe(&pdev->dev, ret, "Error requesting irq at index %d: %d\n",
67 inst->irq_idx, ret);
68
69 return ret;
70 }
71
smi_devs_unregister(struct smi * smi)72 static void smi_devs_unregister(struct smi *smi)
73 {
74 while (smi->i2c_num > 0)
75 i2c_unregister_device(smi->i2c_devs[--smi->i2c_num]);
76
77 while (smi->spi_num > 0)
78 spi_unregister_device(smi->spi_devs[--smi->spi_num]);
79 }
80
81 /**
82 * smi_spi_probe - Instantiate multiple SPI devices from inst array
83 * @pdev: Platform device
84 * @adev: ACPI device
85 * @smi: Internal struct for Serial multi instantiate driver
86 * @inst_array: Array of instances to probe
87 *
88 * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
89 */
smi_spi_probe(struct platform_device * pdev,struct acpi_device * adev,struct smi * smi,const struct smi_instance * inst_array)90 static int smi_spi_probe(struct platform_device *pdev, struct acpi_device *adev, struct smi *smi,
91 const struct smi_instance *inst_array)
92 {
93 struct device *dev = &pdev->dev;
94 struct spi_controller *ctlr;
95 struct spi_device *spi_dev;
96 char name[50];
97 int i, ret, count;
98
99 ret = acpi_spi_count_resources(adev);
100 if (ret < 0)
101 return ret;
102 else if (!ret)
103 return -ENODEV;
104
105 count = ret;
106
107 smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
108 if (!smi->spi_devs)
109 return -ENOMEM;
110
111 for (i = 0; i < count && inst_array[i].type; i++) {
112
113 spi_dev = acpi_spi_device_alloc(NULL, adev, i);
114 if (IS_ERR(spi_dev)) {
115 ret = PTR_ERR(spi_dev);
116 dev_err_probe(dev, ret, "failed to allocate SPI device %s from ACPI: %d\n",
117 dev_name(&adev->dev), ret);
118 goto error;
119 }
120
121 ctlr = spi_dev->controller;
122
123 strscpy(spi_dev->modalias, inst_array[i].type, sizeof(spi_dev->modalias));
124
125 ret = smi_get_irq(pdev, adev, &inst_array[i]);
126 if (ret < 0) {
127 spi_dev_put(spi_dev);
128 goto error;
129 }
130 spi_dev->irq = ret;
131
132 snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
133 inst_array[i].type, i);
134 spi_dev->dev.init_name = name;
135
136 ret = spi_add_device(spi_dev);
137 if (ret) {
138 dev_err_probe(&ctlr->dev, ret,
139 "failed to add SPI device %s from ACPI: %d\n",
140 dev_name(&adev->dev), ret);
141 spi_dev_put(spi_dev);
142 goto error;
143 }
144
145 dev_dbg(dev, "SPI device %s using chip select %u", name, spi_dev->chip_select);
146
147 smi->spi_devs[i] = spi_dev;
148 smi->spi_num++;
149 }
150
151 if (smi->spi_num < count) {
152 dev_dbg(dev, "Error finding driver, idx %d\n", i);
153 ret = -ENODEV;
154 goto error;
155 }
156
157 dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);
158
159 return 0;
160 error:
161 smi_devs_unregister(smi);
162
163 return ret;
164 }
165
166 /**
167 * smi_i2c_probe - Instantiate multiple I2C devices from inst array
168 * @pdev: Platform device
169 * @adev: ACPI device
170 * @smi: Internal struct for Serial multi instantiate driver
171 * @inst_array: Array of instances to probe
172 *
173 * Returns the number of I2C devices instantiate, Zero if none is found or a negative error code.
174 */
smi_i2c_probe(struct platform_device * pdev,struct acpi_device * adev,struct smi * smi,const struct smi_instance * inst_array)175 static int smi_i2c_probe(struct platform_device *pdev, struct acpi_device *adev, struct smi *smi,
176 const struct smi_instance *inst_array)
177 {
178 struct i2c_board_info board_info = {};
179 struct device *dev = &pdev->dev;
180 char name[32];
181 int i, ret, count;
182
183 ret = i2c_acpi_client_count(adev);
184 if (ret < 0)
185 return ret;
186 else if (!ret)
187 return -ENODEV;
188
189 count = ret;
190
191 smi->i2c_devs = devm_kcalloc(dev, count, sizeof(*smi->i2c_devs), GFP_KERNEL);
192 if (!smi->i2c_devs)
193 return -ENOMEM;
194
195 for (i = 0; i < count && inst_array[i].type; i++) {
196 memset(&board_info, 0, sizeof(board_info));
197 strscpy(board_info.type, inst_array[i].type, I2C_NAME_SIZE);
198 snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev), inst_array[i].type, i);
199 board_info.dev_name = name;
200
201 ret = smi_get_irq(pdev, adev, &inst_array[i]);
202 if (ret < 0)
203 goto error;
204 board_info.irq = ret;
205
206 smi->i2c_devs[i] = i2c_acpi_new_device(dev, i, &board_info);
207 if (IS_ERR(smi->i2c_devs[i])) {
208 ret = dev_err_probe(dev, PTR_ERR(smi->i2c_devs[i]),
209 "Error creating i2c-client, idx %d\n", i);
210 goto error;
211 }
212 smi->i2c_num++;
213 }
214 if (smi->i2c_num < count) {
215 dev_dbg(dev, "Error finding driver, idx %d\n", i);
216 ret = -ENODEV;
217 goto error;
218 }
219
220 dev_info(dev, "Instantiated %d I2C devices.\n", smi->i2c_num);
221
222 return 0;
223 error:
224 smi_devs_unregister(smi);
225
226 return ret;
227 }
228
smi_probe(struct platform_device * pdev)229 static int smi_probe(struct platform_device *pdev)
230 {
231 struct device *dev = &pdev->dev;
232 const struct smi_node *node;
233 struct acpi_device *adev;
234 struct smi *smi;
235
236 adev = ACPI_COMPANION(dev);
237 if (!adev)
238 return -ENODEV;
239
240 node = device_get_match_data(dev);
241 if (!node) {
242 dev_dbg(dev, "Error ACPI match data is missing\n");
243 return -ENODEV;
244 }
245
246 smi = devm_kzalloc(dev, sizeof(*smi), GFP_KERNEL);
247 if (!smi)
248 return -ENOMEM;
249
250 platform_set_drvdata(pdev, smi);
251
252 switch (node->bus_type) {
253 case SMI_I2C:
254 return smi_i2c_probe(pdev, adev, smi, node->instances);
255 case SMI_SPI:
256 return smi_spi_probe(pdev, adev, smi, node->instances);
257 case SMI_AUTO_DETECT:
258 if (i2c_acpi_client_count(adev) > 0)
259 return smi_i2c_probe(pdev, adev, smi, node->instances);
260 else
261 return smi_spi_probe(pdev, adev, smi, node->instances);
262 default:
263 return -EINVAL;
264 }
265
266 return 0; /* never reached */
267 }
268
smi_remove(struct platform_device * pdev)269 static int smi_remove(struct platform_device *pdev)
270 {
271 struct smi *smi = platform_get_drvdata(pdev);
272
273 smi_devs_unregister(smi);
274
275 return 0;
276 }
277
278 static const struct smi_node bsg1160_data = {
279 .instances = {
280 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
281 { "bmc150_magn" },
282 { "bmg160" },
283 {}
284 },
285 .bus_type = SMI_I2C,
286 };
287
288 static const struct smi_node bsg2150_data = {
289 .instances = {
290 { "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
291 { "bmc150_magn" },
292 /* The resources describe a 3th client, but it is not really there. */
293 { "bsg2150_dummy_dev" },
294 {}
295 },
296 .bus_type = SMI_I2C,
297 };
298
299 static const struct smi_node int3515_data = {
300 .instances = {
301 { "tps6598x", IRQ_RESOURCE_APIC, 0 },
302 { "tps6598x", IRQ_RESOURCE_APIC, 1 },
303 { "tps6598x", IRQ_RESOURCE_APIC, 2 },
304 { "tps6598x", IRQ_RESOURCE_APIC, 3 },
305 {}
306 },
307 .bus_type = SMI_I2C,
308 };
309
310 static const struct smi_node cs35l41_hda = {
311 .instances = {
312 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
313 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
314 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
315 { "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
316 {}
317 },
318 .bus_type = SMI_AUTO_DETECT,
319 };
320
321 /*
322 * Note new device-ids must also be added to ignore_serial_bus_ids in
323 * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
324 */
325 static const struct acpi_device_id smi_acpi_ids[] = {
326 { "BSG1160", (unsigned long)&bsg1160_data },
327 { "BSG2150", (unsigned long)&bsg2150_data },
328 { "INT3515", (unsigned long)&int3515_data },
329 { "CSC3551", (unsigned long)&cs35l41_hda },
330 /* Non-conforming _HID for Cirrus Logic already released */
331 { "CLSA0100", (unsigned long)&cs35l41_hda },
332 { "CLSA0101", (unsigned long)&cs35l41_hda },
333 { }
334 };
335 MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);
336
337 static struct platform_driver smi_driver = {
338 .driver = {
339 .name = "Serial bus multi instantiate pseudo device driver",
340 .acpi_match_table = smi_acpi_ids,
341 },
342 .probe = smi_probe,
343 .remove = smi_remove,
344 };
345 module_platform_driver(smi_driver);
346
347 MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
348 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
349 MODULE_LICENSE("GPL");
350