summaryrefslogtreecommitdiff
path: root/drivers/platform/x86/serial-multi-instantiate.c
blob: 5362f1a7b77c5df4c654c62c8b14fc09910feb16 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
// SPDX-License-Identifier: GPL-2.0+
/*
 * Serial multi-instantiate driver, pseudo driver to instantiate multiple
 * client devices from a single fwnode.
 *
 * Copyright 2018 Hans de Goede <hdegoede@redhat.com>
 */

#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/spi/spi.h>
#include <linux/types.h>

#define IRQ_RESOURCE_TYPE	GENMASK(1, 0)
#define IRQ_RESOURCE_NONE	0
#define IRQ_RESOURCE_GPIO	1
#define IRQ_RESOURCE_APIC	2

enum smi_bus_type {
	SMI_I2C,
	SMI_SPI,
	SMI_AUTO_DETECT,
};

struct smi_instance {
	const char *type;
	unsigned int flags;
	int irq_idx;
};

struct smi_node {
	enum smi_bus_type bus_type;
	struct smi_instance instances[];
};

struct smi {
	int i2c_num;
	int spi_num;
	struct i2c_client **i2c_devs;
	struct spi_device **spi_devs;
};

static int smi_get_irq(struct platform_device *pdev, struct acpi_device *adev,
		       const struct smi_instance *inst)
{
	int ret;

	switch (inst->flags & IRQ_RESOURCE_TYPE) {
	case IRQ_RESOURCE_GPIO:
		ret = acpi_dev_gpio_irq_get(adev, inst->irq_idx);
		break;
	case IRQ_RESOURCE_APIC:
		ret = platform_get_irq(pdev, inst->irq_idx);
		break;
	default:
		return 0;
	}
	if (ret < 0)
		return dev_err_probe(&pdev->dev, ret, "Error requesting irq at index %d\n",
				     inst->irq_idx);

	return ret;
}

static void smi_devs_unregister(struct smi *smi)
{
	while (smi->i2c_num--)
		i2c_unregister_device(smi->i2c_devs[smi->i2c_num]);

	while (smi->spi_num--)
		spi_unregister_device(smi->spi_devs[smi->spi_num]);
}

/**
 * smi_spi_probe - Instantiate multiple SPI devices from inst array
 * @pdev:	Platform device
 * @smi:	Internal struct for Serial multi instantiate driver
 * @inst_array:	Array of instances to probe
 *
 * Returns the number of SPI devices instantiate, Zero if none is found or a negative error code.
 */
static int smi_spi_probe(struct platform_device *pdev, struct smi *smi,
			 const struct smi_instance *inst_array)
{
	struct device *dev = &pdev->dev;
	struct acpi_device *adev = ACPI_COMPANION(dev);
	struct spi_controller *ctlr;
	struct spi_device *spi_dev;
	char name[50];
	int i, ret, count;

	ret = acpi_spi_count_resources(adev);
	if (ret < 0)
		return ret;
	if (!ret)
		return -ENOENT;

	count = ret;

	smi->spi_devs = devm_kcalloc(dev, count, sizeof(*smi->spi_devs), GFP_KERNEL);
	if (!smi->spi_devs)
		return -ENOMEM;

	for (i = 0; i < count && inst_array[i].type; i++) {

		spi_dev = acpi_spi_device_alloc(NULL, adev, i);
		if (IS_ERR(spi_dev)) {
			ret = dev_err_probe(dev, PTR_ERR(spi_dev), "failed to allocate SPI device %s from ACPI\n",
					    dev_name(&adev->dev));
			goto error;
		}

		ctlr = spi_dev->controller;

		strscpy(spi_dev->modalias, inst_array[i].type, sizeof(spi_dev->modalias));

		ret = smi_get_irq(pdev, adev, &inst_array[i]);
		if (ret < 0) {
			spi_dev_put(spi_dev);
			goto error;
		}
		spi_dev->irq = ret;

		snprintf(name, sizeof(name), "%s-%s-%s.%d", dev_name(&ctlr->dev), dev_name(dev),
			 inst_array[i].type, i);
		spi_dev->dev.init_name = name;

		ret = spi_add_device(spi_dev);
		if (ret) {
			dev_err_probe(&ctlr->dev, ret, "failed to add SPI device %s from ACPI\n",
				      dev_name(&adev->dev));
			spi_dev_put(spi_dev);
			goto error;
		}

		dev_dbg(dev, "SPI device %s using chip select %u", name, spi_dev->chip_select);

		smi->spi_devs[i] = spi_dev;
		smi->spi_num++;
	}

	if (smi->spi_num < count) {
		dev_dbg(dev, "Error finding driver, idx %d\n", i);
		ret = -ENODEV;
		goto error;
	}

	dev_info(dev, "Instantiated %d SPI devices.\n", smi->spi_num);

	return 0;
error:
	smi_devs_unregister(smi);

	return ret;
}

/**
 * smi_i2c_probe - Instantiate multiple I2C devices from inst array
 * @pdev:	Platform device
 * @smi:	Internal struct for Serial multi instantiate driver
 * @inst_array:	Array of instances to probe
 *
 * Returns the number of I2C devices instantiate, Zero if none is found or a negative error code.
 */
static int smi_i2c_probe(struct platform_device *pdev, struct smi *smi,
			 const struct smi_instance *inst_array)
{
	struct i2c_board_info board_info = {};
	struct device *dev = &pdev->dev;
	struct acpi_device *adev = ACPI_COMPANION(dev);
	char name[32];
	int i, ret, count;

	ret = i2c_acpi_client_count(adev);
	if (ret < 0)
		return ret;
	if (!ret)
		return -ENOENT;

	count = ret;

	smi->i2c_devs = devm_kcalloc(dev, count, sizeof(*smi->i2c_devs), GFP_KERNEL);
	if (!smi->i2c_devs)
		return -ENOMEM;

	for (i = 0; i < count && inst_array[i].type; i++) {
		memset(&board_info, 0, sizeof(board_info));
		strscpy(board_info.type, inst_array[i].type, I2C_NAME_SIZE);
		snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev), inst_array[i].type, i);
		board_info.dev_name = name;

		ret = smi_get_irq(pdev, adev, &inst_array[i]);
		if (ret < 0)
			goto error;
		board_info.irq = ret;

		smi->i2c_devs[i] = i2c_acpi_new_device(dev, i, &board_info);
		if (IS_ERR(smi->i2c_devs[i])) {
			ret = dev_err_probe(dev, PTR_ERR(smi->i2c_devs[i]),
					    "Error creating i2c-client, idx %d\n", i);
			goto error;
		}
		smi->i2c_num++;
	}
	if (smi->i2c_num < count) {
		dev_dbg(dev, "Error finding driver, idx %d\n", i);
		ret = -ENODEV;
		goto error;
	}

	dev_info(dev, "Instantiated %d I2C devices.\n", smi->i2c_num);

	return 0;
error:
	smi_devs_unregister(smi);

	return ret;
}

static int smi_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	const struct smi_node *node;
	struct smi *smi;
	int ret;

	node = device_get_match_data(dev);
	if (!node) {
		dev_dbg(dev, "Error ACPI match data is missing\n");
		return -ENODEV;
	}

	smi = devm_kzalloc(dev, sizeof(*smi), GFP_KERNEL);
	if (!smi)
		return -ENOMEM;

	platform_set_drvdata(pdev, smi);

	switch (node->bus_type) {
	case SMI_I2C:
		return smi_i2c_probe(pdev, smi, node->instances);
	case SMI_SPI:
		return smi_spi_probe(pdev, smi, node->instances);
	case SMI_AUTO_DETECT:
		/*
		 * For backwards-compatibility with the existing nodes I2C
		 * is checked first and if such entries are found ONLY I2C
		 * devices are created. Since some existing nodes that were
		 * already handled by this driver could also contain unrelated
		 * SpiSerialBus nodes that were previously ignored, and this
		 * preserves that behavior.
		 */
		ret = smi_i2c_probe(pdev, smi, node->instances);
		if (ret != -ENOENT)
			return ret;
		return smi_spi_probe(pdev, smi, node->instances);
	default:
		return -EINVAL;
	}
}

static int smi_remove(struct platform_device *pdev)
{
	struct smi *smi = platform_get_drvdata(pdev);

	smi_devs_unregister(smi);

	return 0;
}

static const struct smi_node bsg1160_data = {
	.instances = {
		{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
		{ "bmc150_magn" },
		{ "bmg160" },
		{}
	},
	.bus_type = SMI_I2C,
};

static const struct smi_node bsg2150_data = {
	.instances = {
		{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
		{ "bmc150_magn" },
		/* The resources describe a 3th client, but it is not really there. */
		{ "bsg2150_dummy_dev" },
		{}
	},
	.bus_type = SMI_I2C,
};

static const struct smi_node int3515_data = {
	.instances = {
		{ "tps6598x", IRQ_RESOURCE_APIC, 0 },
		{ "tps6598x", IRQ_RESOURCE_APIC, 1 },
		{ "tps6598x", IRQ_RESOURCE_APIC, 2 },
		{ "tps6598x", IRQ_RESOURCE_APIC, 3 },
		{}
	},
	.bus_type = SMI_I2C,
};

static const struct smi_node cs35l41_hda = {
	.instances = {
		{ "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
		{ "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
		{ "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
		{ "cs35l41-hda", IRQ_RESOURCE_GPIO, 0 },
		{}
	},
	.bus_type = SMI_AUTO_DETECT,
};

/*
 * Note new device-ids must also be added to ignore_serial_bus_ids in
 * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
 */
static const struct acpi_device_id smi_acpi_ids[] = {
	{ "BSG1160", (unsigned long)&bsg1160_data },
	{ "BSG2150", (unsigned long)&bsg2150_data },
	{ "CSC3551", (unsigned long)&cs35l41_hda },
	{ "INT3515", (unsigned long)&int3515_data },
	/* Non-conforming _HID for Cirrus Logic already released */
	{ "CLSA0100", (unsigned long)&cs35l41_hda },
	{ "CLSA0101", (unsigned long)&cs35l41_hda },
	{ }
};
MODULE_DEVICE_TABLE(acpi, smi_acpi_ids);

static struct platform_driver smi_driver = {
	.driver	= {
		.name = "Serial bus multi instantiate pseudo device driver",
		.acpi_match_table = smi_acpi_ids,
	},
	.probe = smi_probe,
	.remove = smi_remove,
};
module_platform_driver(smi_driver);

MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_LICENSE("GPL");