// 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 <[email protected]>
*/
#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
#define IRQ_RESOURCE_AUTO 3
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_AUTO:
ret = acpi_dev_gpio_irq_get(adev, inst->irq_idx);
if (ret > 0) {
dev_dbg(&pdev->dev, "Using gpio irq\n");
break;
}
ret = platform_get_irq(pdev, inst->irq_idx);
if (ret > 0) {
dev_dbg(&pdev->dev, "Using platform irq\n");
break;
}
break;
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)
{
#if IS_REACHABLE(CONFIG_I2C)
while (smi->i2c_num--)
i2c_unregister_device(smi->i2c_devs[smi->i2c_num]);
#endif
if (IS_REACHABLE(CONFIG_SPI)) {
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);
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_get_chipselect(spi_dev, 0));
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);
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:
if (IS_REACHABLE(CONFIG_I2C))
return smi_i2c_probe(pdev, smi, node->instances);
return -ENODEV;
case SMI_SPI:
if (IS_REACHABLE(CONFIG_SPI))
return smi_spi_probe(pdev, smi, node->instances);
return -ENODEV;
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.
*/
if (IS_REACHABLE(CONFIG_I2C)) {
ret = smi_i2c_probe(pdev, smi, node->instances);
if (ret != -ENOENT)
return ret;
}
if (IS_REACHABLE(CONFIG_SPI))
return smi_spi_probe(pdev, smi, node->instances);
return -ENODEV;
default:
return -EINVAL;
}
}
static void smi_remove(struct platform_device *pdev)
{
struct smi *smi = platform_get_drvdata(pdev);
smi_devs_unregister(smi);
}
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_AUTO, 0 },
{ "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l41-hda", IRQ_RESOURCE_AUTO, 0 },
{}
},
.bus_type = SMI_AUTO_DETECT,
};
static const struct smi_node cs35l54_hda = {
.instances = {
{ "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l54-hda", IRQ_RESOURCE_AUTO, 0 },
/* a 5th entry is an alias address, not a real device */
{ "cs35l54-hda_dummy_dev" },
{}
},
.bus_type = SMI_AUTO_DETECT,
};
static const struct smi_node cs35l56_hda = {
.instances = {
{ "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l56-hda", IRQ_RESOURCE_AUTO, 0 },
/* a 5th entry is an alias address, not a real device */
{ "cs35l56-hda_dummy_dev" },
{}
},
.bus_type = SMI_AUTO_DETECT,
};
static const struct smi_node cs35l57_hda = {
.instances = {
{ "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
{ "cs35l57-hda", IRQ_RESOURCE_AUTO, 0 },
/* a 5th entry is an alias address, not a real device */
{ "cs35l57-hda_dummy_dev" },
{}
},
.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 },
{ "CSC3554", (unsigned long)&cs35l54_hda },
{ "CSC3556", (unsigned long)&cs35l56_hda },
{ "CSC3557", (unsigned long)&cs35l57_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_new = smi_remove,
};
module_platform_driver(smi_driver);
MODULE_DESCRIPTION("Serial multi instantiate pseudo device driver");
MODULE_AUTHOR("Hans de Goede <[email protected]>");
MODULE_LICENSE("GPL");
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