linux/drivers/platform/x86/i2c-multi-instantiate.c
Heikki Krogerus 24a8d78a9a platform/x86: i2c-multi-instantiate: Derive the device name from parent
When naming the new devices, instead of using the ACPI ID in
the name as base, using the parent device's name. That makes
it possible to support multiple multi-instance i2c devices
of the same type in the same system.

This fixes an issue seen on some Intel Kaby Lake based
boards:

sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:15.0/i2c_designware.0/i2c-0/i2c-INT3515-tps6598x.0'

Fixes: 2336dfadfb ("platform/x86: i2c-multi-instantiate: Allow to have same slaves")
Cc: stable@vger.kernel.org
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2019-09-20 17:57:07 +03:00

201 lines
4.9 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* I2C multi-instantiate driver, pseudo driver to instantiate multiple
* i2c-clients 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/types.h>
#define IRQ_RESOURCE_TYPE GENMASK(1, 0)
#define IRQ_RESOURCE_NONE 0
#define IRQ_RESOURCE_GPIO 1
#define IRQ_RESOURCE_APIC 2
struct i2c_inst_data {
const char *type;
unsigned int flags;
int irq_idx;
};
struct i2c_multi_inst_data {
int num_clients;
struct i2c_client *clients[0];
};
static int i2c_multi_inst_count(struct acpi_resource *ares, void *data)
{
struct acpi_resource_i2c_serialbus *sb;
int *count = data;
if (i2c_acpi_get_i2c_resource(ares, &sb))
*count = *count + 1;
return 1;
}
static int i2c_multi_inst_count_resources(struct acpi_device *adev)
{
LIST_HEAD(r);
int count = 0;
int ret;
ret = acpi_dev_get_resources(adev, &r, i2c_multi_inst_count, &count);
if (ret < 0)
return ret;
acpi_dev_free_resource_list(&r);
return count;
}
static int i2c_multi_inst_probe(struct platform_device *pdev)
{
struct i2c_multi_inst_data *multi;
const struct acpi_device_id *match;
const struct i2c_inst_data *inst_data;
struct i2c_board_info board_info = {};
struct device *dev = &pdev->dev;
struct acpi_device *adev;
char name[32];
int i, ret;
match = acpi_match_device(dev->driver->acpi_match_table, dev);
if (!match) {
dev_err(dev, "Error ACPI match data is missing\n");
return -ENODEV;
}
inst_data = (const struct i2c_inst_data *)match->driver_data;
adev = ACPI_COMPANION(dev);
/* Count number of clients to instantiate */
ret = i2c_multi_inst_count_resources(adev);
if (ret < 0)
return ret;
multi = devm_kmalloc(dev, struct_size(multi, clients, ret), GFP_KERNEL);
if (!multi)
return -ENOMEM;
multi->num_clients = ret;
for (i = 0; i < multi->num_clients && inst_data[i].type; i++) {
memset(&board_info, 0, sizeof(board_info));
strlcpy(board_info.type, inst_data[i].type, I2C_NAME_SIZE);
snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev),
inst_data[i].type, i);
board_info.dev_name = name;
switch (inst_data[i].flags & IRQ_RESOURCE_TYPE) {
case IRQ_RESOURCE_GPIO:
ret = acpi_dev_gpio_irq_get(adev, inst_data[i].irq_idx);
if (ret < 0) {
dev_err(dev, "Error requesting irq at index %d: %d\n",
inst_data[i].irq_idx, ret);
goto error;
}
board_info.irq = ret;
break;
case IRQ_RESOURCE_APIC:
ret = platform_get_irq(pdev, inst_data[i].irq_idx);
if (ret < 0) {
dev_dbg(dev, "Error requesting irq at index %d: %d\n",
inst_data[i].irq_idx, ret);
}
board_info.irq = ret;
break;
default:
board_info.irq = 0;
break;
}
multi->clients[i] = i2c_acpi_new_device(dev, i, &board_info);
if (IS_ERR(multi->clients[i])) {
ret = PTR_ERR(multi->clients[i]);
if (ret != -EPROBE_DEFER)
dev_err(dev, "Error creating i2c-client, idx %d\n", i);
goto error;
}
}
if (i < multi->num_clients) {
dev_err(dev, "Error finding driver, idx %d\n", i);
ret = -ENODEV;
goto error;
}
platform_set_drvdata(pdev, multi);
return 0;
error:
while (--i >= 0)
i2c_unregister_device(multi->clients[i]);
return ret;
}
static int i2c_multi_inst_remove(struct platform_device *pdev)
{
struct i2c_multi_inst_data *multi = platform_get_drvdata(pdev);
int i;
for (i = 0; i < multi->num_clients; i++)
i2c_unregister_device(multi->clients[i]);
return 0;
}
static const struct i2c_inst_data bsg1160_data[] = {
{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
{ "bmc150_magn" },
{ "bmg160" },
{}
};
static const struct i2c_inst_data bsg2150_data[] = {
{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
{ "bmc150_magn" },
/* The resources describe a 3th client, but it is not really there. */
{ "bsg2150_dummy_dev" },
{}
};
static const struct i2c_inst_data int3515_data[] = {
{ "tps6598x", IRQ_RESOURCE_APIC, 0 },
{ "tps6598x", IRQ_RESOURCE_APIC, 1 },
{ "tps6598x", IRQ_RESOURCE_APIC, 2 },
{ "tps6598x", IRQ_RESOURCE_APIC, 3 },
{}
};
/*
* Note new device-ids must also be added to i2c_multi_instantiate_ids in
* drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
*/
static const struct acpi_device_id i2c_multi_inst_acpi_ids[] = {
{ "BSG1160", (unsigned long)bsg1160_data },
{ "BSG2150", (unsigned long)bsg2150_data },
{ "INT3515", (unsigned long)int3515_data },
{ }
};
MODULE_DEVICE_TABLE(acpi, i2c_multi_inst_acpi_ids);
static struct platform_driver i2c_multi_inst_driver = {
.driver = {
.name = "I2C multi instantiate pseudo device driver",
.acpi_match_table = ACPI_PTR(i2c_multi_inst_acpi_ids),
},
.probe = i2c_multi_inst_probe,
.remove = i2c_multi_inst_remove,
};
module_platform_driver(i2c_multi_inst_driver);
MODULE_DESCRIPTION("I2C multi instantiate pseudo device driver");
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_LICENSE("GPL");