1 files changed, 348 insertions, 0 deletions
diff --git a/drivers/platform/x86/serial-multi-instantiate.c b/drivers/platform/x86/serial-multi-instantiate.c
new file mode 100644
index 000000000000..1e8063b7c169
--- /dev/null
+++ b/drivers/platform/x86/serial-multi-instantiate.c
@@ -0,0 +1,348 @@
+// 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)
+		dev_err_probe(&pdev->dev, ret, "Error requesting irq at index %d: %d\n",
+			      inst->irq_idx, ret);
+
+	return ret;
+}
+
+static void smi_devs_unregister(struct smi *smi)
+{
+	while (smi->i2c_num > 0)
+		i2c_unregister_device(smi->i2c_devs[--smi->i2c_num]);
+
+	while (smi->spi_num > 0)
+		spi_unregister_device(smi->spi_devs[--smi->spi_num]);
+}
+
+/**
+ * smi_spi_probe - Instantiate multiple SPI devices from inst array
+ * @pdev:	Platform device
+ * @adev:	ACPI 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 acpi_device *adev, struct smi *smi,
+			 const struct smi_instance *inst_array)
+{
+	struct device *dev = &pdev->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;
+	else if (!ret)
+		return -ENODEV;
+
+	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 = PTR_ERR(spi_dev);
+			dev_err_probe(dev, ret, "failed to allocate SPI device %s from ACPI: %d\n",
+				      dev_name(&adev->dev), ret);
+			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: %d\n",
+				      dev_name(&adev->dev), ret);
+			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
+ * @adev:	ACPI 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 acpi_device *adev, struct smi *smi,
+			 const struct smi_instance *inst_array)
+{
+	struct i2c_board_info board_info = {};
+	struct device *dev = &pdev->dev;
+	char name[32];
+	int i, ret, count;
+
+	ret = i2c_acpi_client_count(adev);
+	if (ret < 0)
+		return ret;
+	else if (!ret)
+		return -ENODEV;
+
+	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 acpi_device *adev;
+	struct smi *smi;
+
+	adev = ACPI_COMPANION(dev);
+	if (!adev)
+		return -ENODEV;
+
+	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, adev, smi, node->instances);
+	case SMI_SPI:
+		return smi_spi_probe(pdev, adev, smi, node->instances);
+	case SMI_AUTO_DETECT:
+		if (i2c_acpi_client_count(adev) > 0)
+			return smi_i2c_probe(pdev, adev, smi, node->instances);
+		else
+			return smi_spi_probe(pdev, adev, smi, node->instances);
+	default:
+		return -EINVAL;
+	}
+
+	return 0; /* never reached */
+}
+
+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 },
+	{ "INT3515", (unsigned long)&int3515_data },
+	{ "CSC3551", (unsigned long)&cs35l41_hda },
+	/* Non-conforming _HID for Cirrus Logic already released */
+	{ "CLSA0100", (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");