linux-zen-server/drivers/platform/x86/intel/int3472/discrete.c

402 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* Author: Dan Scally <djrscally@gmail.com> */
#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/machine.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/overflow.h>
#include <linux/platform_device.h>
#include <linux/uuid.h>
#include "common.h"
/*
* 79234640-9e10-4fea-a5c1-b5aa8b19756f
* This _DSM GUID returns information about the GPIO lines mapped to a
* discrete INT3472 device. Function number 1 returns a count of the GPIO
* lines that are mapped. Subsequent functions return 32 bit ints encoding
* information about the GPIO line, including its purpose.
*/
static const guid_t int3472_gpio_guid =
GUID_INIT(0x79234640, 0x9e10, 0x4fea,
0xa5, 0xc1, 0xb5, 0xaa, 0x8b, 0x19, 0x75, 0x6f);
/*
* 822ace8f-2814-4174-a56b-5f029fe079ee
* This _DSM GUID returns a string from the sensor device, which acts as a
* module identifier.
*/
static const guid_t cio2_sensor_module_guid =
GUID_INIT(0x822ace8f, 0x2814, 0x4174,
0xa5, 0x6b, 0x5f, 0x02, 0x9f, 0xe0, 0x79, 0xee);
/*
* Here follows platform specific mapping information that we can pass to
* the functions mapping resources to the sensors. Where the sensors have
* a power enable pin defined in DSDT we need to provide a supply name so
* the sensor drivers can find the regulator. The device name will be derived
* from the sensor's ACPI device within the code. Optionally, we can provide a
* NULL terminated array of function name mappings to deal with any platform
* specific deviations from the documented behaviour of GPIOs.
*
* Map a GPIO function name to NULL to prevent the driver from mapping that
* GPIO at all.
*/
static const struct int3472_gpio_function_remap ov2680_gpio_function_remaps[] = {
{ "reset", NULL },
{ "powerdown", "reset" },
{ }
};
static const struct int3472_sensor_config int3472_sensor_configs[] = {
/* Lenovo Miix 510-12ISK - OV2680, Front */
{ "GNDF140809R", { 0 }, ov2680_gpio_function_remaps },
/* Lenovo Miix 510-12ISK - OV5648, Rear */
{ "GEFF150023R", REGULATOR_SUPPLY("avdd", NULL), NULL },
/* Surface Go 1&2 - OV5693, Front */
{ "YHCU", REGULATOR_SUPPLY("avdd", NULL), NULL },
};
static const struct int3472_sensor_config *
skl_int3472_get_sensor_module_config(struct int3472_discrete_device *int3472)
{
union acpi_object *obj;
unsigned int i;
obj = acpi_evaluate_dsm_typed(int3472->sensor->handle,
&cio2_sensor_module_guid, 0x00,
0x01, NULL, ACPI_TYPE_STRING);
if (!obj) {
dev_err(int3472->dev,
"Failed to get sensor module string from _DSM\n");
return ERR_PTR(-ENODEV);
}
for (i = 0; i < ARRAY_SIZE(int3472_sensor_configs); i++) {
if (!strcmp(int3472_sensor_configs[i].sensor_module_name,
obj->string.pointer))
break;
}
ACPI_FREE(obj);
if (i >= ARRAY_SIZE(int3472_sensor_configs))
return ERR_PTR(-EINVAL);
return &int3472_sensor_configs[i];
}
static int skl_int3472_map_gpio_to_sensor(struct int3472_discrete_device *int3472,
struct acpi_resource_gpio *agpio,
const char *func, u32 polarity)
{
const struct int3472_sensor_config *sensor_config;
char *path = agpio->resource_source.string_ptr;
struct gpiod_lookup *table_entry;
struct acpi_device *adev;
acpi_handle handle;
acpi_status status;
if (int3472->n_sensor_gpios >= INT3472_MAX_SENSOR_GPIOS) {
dev_warn(int3472->dev, "Too many GPIOs mapped\n");
return -EINVAL;
}
sensor_config = int3472->sensor_config;
if (!IS_ERR(sensor_config) && sensor_config->function_maps) {
const struct int3472_gpio_function_remap *remap;
for (remap = sensor_config->function_maps; remap->documented; remap++) {
if (!strcmp(func, remap->documented)) {
func = remap->actual;
break;
}
}
}
/* Functions mapped to NULL should not be mapped to the sensor */
if (!func)
return 0;
status = acpi_get_handle(NULL, path, &handle);
if (ACPI_FAILURE(status))
return -EINVAL;
adev = acpi_fetch_acpi_dev(handle);
if (!adev)
return -ENODEV;
table_entry = &int3472->gpios.table[int3472->n_sensor_gpios];
table_entry->key = acpi_dev_name(adev);
table_entry->chip_hwnum = agpio->pin_table[0];
table_entry->con_id = func;
table_entry->idx = 0;
table_entry->flags = polarity;
int3472->n_sensor_gpios++;
return 0;
}
static void int3472_get_func_and_polarity(u8 type, const char **func, u32 *polarity)
{
switch (type) {
case INT3472_GPIO_TYPE_RESET:
*func = "reset";
*polarity = GPIO_ACTIVE_LOW;
break;
case INT3472_GPIO_TYPE_POWERDOWN:
*func = "powerdown";
*polarity = GPIO_ACTIVE_LOW;
break;
case INT3472_GPIO_TYPE_CLK_ENABLE:
*func = "clk-enable";
*polarity = GPIO_ACTIVE_HIGH;
break;
case INT3472_GPIO_TYPE_PRIVACY_LED:
*func = "privacy-led";
*polarity = GPIO_ACTIVE_HIGH;
break;
case INT3472_GPIO_TYPE_POWER_ENABLE:
*func = "power-enable";
*polarity = GPIO_ACTIVE_HIGH;
break;
default:
*func = "unknown";
*polarity = GPIO_ACTIVE_HIGH;
break;
}
}
/**
* skl_int3472_handle_gpio_resources: Map PMIC resources to consuming sensor
* @ares: A pointer to a &struct acpi_resource
* @data: A pointer to a &struct int3472_discrete_device
*
* This function handles GPIO resources that are against an INT3472
* ACPI device, by checking the value of the corresponding _DSM entry.
* This will return a 32bit int, where the lowest byte represents the
* function of the GPIO pin:
*
* 0x00 Reset
* 0x01 Power down
* 0x0b Power enable
* 0x0c Clock enable
* 0x0d Privacy LED
*
* There are some known platform specific quirks where that does not quite
* hold up; for example where a pin with type 0x01 (Power down) is mapped to
* a sensor pin that performs a reset function or entries in _CRS and _DSM that
* do not actually correspond to a physical connection. These will be handled
* by the mapping sub-functions.
*
* GPIOs will either be mapped directly to the sensor device or else used
* to create clocks and regulators via the usual frameworks.
*
* Return:
* * 1 - To continue the loop
* * 0 - When all resources found are handled properly.
* * -EINVAL - If the resource is not a GPIO IO resource
* * -ENODEV - If the resource has no corresponding _DSM entry
* * -Other - Errors propagated from one of the sub-functions.
*/
static int skl_int3472_handle_gpio_resources(struct acpi_resource *ares,
void *data)
{
struct int3472_discrete_device *int3472 = data;
struct acpi_resource_gpio *agpio;
union acpi_object *obj;
u8 active_value, type;
const char *err_msg;
const char *func;
u32 polarity;
int ret;
if (!acpi_gpio_get_io_resource(ares, &agpio))
return 1;
/*
* ngpios + 2 because the index of this _DSM function is 1-based and
* the first function is just a count.
*/
obj = acpi_evaluate_dsm_typed(int3472->adev->handle,
&int3472_gpio_guid, 0x00,
int3472->ngpios + 2,
NULL, ACPI_TYPE_INTEGER);
if (!obj) {
dev_warn(int3472->dev, "No _DSM entry for GPIO pin %u\n",
agpio->pin_table[0]);
return 1;
}
type = obj->integer.value & 0xff;
int3472_get_func_and_polarity(type, &func, &polarity);
/* If bits 31-24 of the _DSM entry are all 0 then the signal is inverted */
active_value = obj->integer.value >> 24;
if (!active_value)
polarity ^= GPIO_ACTIVE_LOW;
dev_dbg(int3472->dev, "%s %s pin %d active-%s\n", func,
agpio->resource_source.string_ptr, agpio->pin_table[0],
(polarity == GPIO_ACTIVE_HIGH) ? "high" : "low");
switch (type) {
case INT3472_GPIO_TYPE_RESET:
case INT3472_GPIO_TYPE_POWERDOWN:
ret = skl_int3472_map_gpio_to_sensor(int3472, agpio, func, polarity);
if (ret)
err_msg = "Failed to map GPIO pin to sensor\n";
break;
case INT3472_GPIO_TYPE_CLK_ENABLE:
ret = skl_int3472_register_clock(int3472, agpio, polarity);
if (ret)
err_msg = "Failed to register clock\n";
break;
case INT3472_GPIO_TYPE_PRIVACY_LED:
ret = skl_int3472_register_pled(int3472, agpio, polarity);
if (ret)
err_msg = "Failed to register LED\n";
break;
case INT3472_GPIO_TYPE_POWER_ENABLE:
ret = skl_int3472_register_regulator(int3472, agpio);
if (ret)
err_msg = "Failed to map regulator to sensor\n";
break;
default:
dev_warn(int3472->dev,
"GPIO type 0x%02x unknown; the sensor may not work\n",
type);
ret = 1;
break;
}
int3472->ngpios++;
ACPI_FREE(obj);
if (ret < 0)
return dev_err_probe(int3472->dev, ret, err_msg);
return ret;
}
static int skl_int3472_parse_crs(struct int3472_discrete_device *int3472)
{
LIST_HEAD(resource_list);
int ret;
/*
* No error check, because not having a sensor config is not necessarily
* a failure mode.
*/
int3472->sensor_config = skl_int3472_get_sensor_module_config(int3472);
ret = acpi_dev_get_resources(int3472->adev, &resource_list,
skl_int3472_handle_gpio_resources,
int3472);
if (ret < 0)
return ret;
acpi_dev_free_resource_list(&resource_list);
int3472->gpios.dev_id = int3472->sensor_name;
gpiod_add_lookup_table(&int3472->gpios);
return 0;
}
static int skl_int3472_discrete_remove(struct platform_device *pdev)
{
struct int3472_discrete_device *int3472 = platform_get_drvdata(pdev);
gpiod_remove_lookup_table(&int3472->gpios);
skl_int3472_unregister_clock(int3472);
skl_int3472_unregister_pled(int3472);
skl_int3472_unregister_regulator(int3472);
return 0;
}
static int skl_int3472_discrete_probe(struct platform_device *pdev)
{
struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
struct int3472_discrete_device *int3472;
struct int3472_cldb cldb;
int ret;
ret = skl_int3472_fill_cldb(adev, &cldb);
if (ret) {
dev_err(&pdev->dev, "Couldn't fill CLDB structure\n");
return ret;
}
if (cldb.control_logic_type != 1) {
dev_err(&pdev->dev, "Unsupported control logic type %u\n",
cldb.control_logic_type);
return -EINVAL;
}
/* Max num GPIOs we've seen plus a terminator */
int3472 = devm_kzalloc(&pdev->dev, struct_size(int3472, gpios.table,
INT3472_MAX_SENSOR_GPIOS + 1), GFP_KERNEL);
if (!int3472)
return -ENOMEM;
int3472->adev = adev;
int3472->dev = &pdev->dev;
platform_set_drvdata(pdev, int3472);
ret = skl_int3472_get_sensor_adev_and_name(&pdev->dev, &int3472->sensor,
&int3472->sensor_name);
if (ret)
return ret;
/*
* Initialising this list means we can call gpiod_remove_lookup_table()
* in failure paths without issue.
*/
INIT_LIST_HEAD(&int3472->gpios.list);
ret = skl_int3472_parse_crs(int3472);
if (ret) {
skl_int3472_discrete_remove(pdev);
return ret;
}
acpi_dev_clear_dependencies(adev);
return 0;
}
static const struct acpi_device_id int3472_device_id[] = {
{ "INT3472", 0 },
{ }
};
MODULE_DEVICE_TABLE(acpi, int3472_device_id);
static struct platform_driver int3472_discrete = {
.driver = {
.name = "int3472-discrete",
.acpi_match_table = int3472_device_id,
},
.probe = skl_int3472_discrete_probe,
.remove = skl_int3472_discrete_remove,
};
module_platform_driver(int3472_discrete);
MODULE_DESCRIPTION("Intel SkyLake INT3472 ACPI Discrete Device Driver");
MODULE_AUTHOR("Daniel Scally <djrscally@gmail.com>");
MODULE_LICENSE("GPL v2");