u-boot/drivers/i2c/acpi_i2c.c
Simon Glass fd42f263ce i2c: Add a generic driver to generate ACPI info
Many I2C devices produce roughly the same ACPI data with just things like
the GPIO/interrupt information being different.

This can be handled by a generic driver along with some information in the
device tree.

Add a generic i2c driver for this purpose.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heiko Schocher <hs@denx.de>
2020-09-25 11:27:15 +08:00

226 lines
6.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright 2019 Google LLC
*/
#include <common.h>
#include <dm.h>
#include <i2c.h>
#include <log.h>
#include <acpi/acpi_device.h>
#include <acpi/acpigen.h>
#include <acpi/acpi_dp.h>
#ifdef CONFIG_X86
#include <asm/intel_pinctrl_defs.h>
#endif
#include <asm-generic/gpio.h>
#include <dm/acpi.h>
static bool acpi_i2c_add_gpios_to_crs(struct acpi_i2c_priv *priv)
{
/*
* Return false if:
* 1. Request to explicitly disable export of GPIOs in CRS, or
* 2. Both reset and enable GPIOs are not provided.
*/
if (priv->disable_gpio_export_in_crs ||
(!dm_gpio_is_valid(&priv->reset_gpio) &&
!dm_gpio_is_valid(&priv->enable_gpio)))
return false;
return true;
}
static int acpi_i2c_write_gpio(struct acpi_ctx *ctx, struct gpio_desc *gpio,
int *curindex)
{
int ret;
if (!dm_gpio_is_valid(gpio))
return -ENOENT;
acpi_device_write_gpio_desc(ctx, gpio);
ret = *curindex;
(*curindex)++;
return ret;
}
int acpi_i2c_fill_ssdt(const struct udevice *dev, struct acpi_ctx *ctx)
{
int reset_gpio_index = -1, enable_gpio_index = -1, irq_gpio_index = -1;
enum i2c_device_t type = dev_get_driver_data(dev);
struct acpi_i2c_priv *priv = dev_get_priv(dev);
struct acpi_dp *dsd = NULL;
char scope[ACPI_PATH_MAX];
char name[ACPI_NAME_MAX];
int tx_state_val;
int curindex = 0;
int ret;
#ifdef CONFIG_X86
tx_state_val = PAD_CFG0_TX_STATE;
#elif defined(CONFIG_SANDBOX)
tx_state_val = BIT(7); /* test value */
#else
#error "Not supported on this architecture"
#endif
ret = acpi_get_name(dev, name);
if (ret)
return log_msg_ret("name", ret);
ret = acpi_device_scope(dev, scope, sizeof(scope));
if (ret)
return log_msg_ret("scope", ret);
/* Device */
acpigen_write_scope(ctx, scope);
acpigen_write_device(ctx, name);
acpigen_write_name_string(ctx, "_HID", priv->hid);
if (type == I2C_DEVICE_HID_OVER_I2C)
acpigen_write_name_string(ctx, "_CID", "PNP0C50");
acpigen_write_name_integer(ctx, "_UID", priv->uid);
acpigen_write_name_string(ctx, "_DDN", priv->desc);
acpigen_write_sta(ctx, acpi_device_status(dev));
/* Resources */
acpigen_write_name(ctx, "_CRS");
acpigen_write_resourcetemplate_header(ctx);
acpi_device_write_i2c_dev(ctx, dev);
/* Use either Interrupt() or GpioInt() */
if (dm_gpio_is_valid(&priv->irq_gpio)) {
irq_gpio_index = acpi_i2c_write_gpio(ctx, &priv->irq_gpio,
&curindex);
} else {
ret = acpi_device_write_interrupt_irq(ctx, &priv->irq);
if (ret < 0)
return log_msg_ret("irq", ret);
}
if (acpi_i2c_add_gpios_to_crs(priv)) {
reset_gpio_index = acpi_i2c_write_gpio(ctx, &priv->reset_gpio,
&curindex);
enable_gpio_index = acpi_i2c_write_gpio(ctx, &priv->enable_gpio,
&curindex);
}
acpigen_write_resourcetemplate_footer(ctx);
/* Wake capabilities */
if (priv->wake) {
acpigen_write_name_integer(ctx, "_S0W", 4);
acpigen_write_prw(ctx, priv->wake, 3);
}
/* DSD */
if (priv->probed || priv->property_count || priv->compat_string ||
reset_gpio_index >= 0 || enable_gpio_index >= 0 ||
irq_gpio_index >= 0) {
char path[ACPI_PATH_MAX];
ret = acpi_device_path(dev, path, sizeof(path));
if (ret)
return log_msg_ret("path", ret);
dsd = acpi_dp_new_table("_DSD");
if (priv->compat_string)
acpi_dp_add_string(dsd, "compatible",
priv->compat_string);
if (priv->probed)
acpi_dp_add_integer(dsd, "linux,probed", 1);
if (irq_gpio_index >= 0)
acpi_dp_add_gpio(dsd, "irq-gpios", path,
irq_gpio_index, 0,
priv->irq_gpio.flags &
GPIOD_ACTIVE_LOW ?
ACPI_GPIO_ACTIVE_LOW : 0);
if (reset_gpio_index >= 0)
acpi_dp_add_gpio(dsd, "reset-gpios", path,
reset_gpio_index, 0,
priv->reset_gpio.flags &
GPIOD_ACTIVE_LOW ?
ACPI_GPIO_ACTIVE_LOW : 0);
if (enable_gpio_index >= 0)
acpi_dp_add_gpio(dsd, "enable-gpios", path,
enable_gpio_index, 0,
priv->enable_gpio.flags &
GPIOD_ACTIVE_LOW ?
ACPI_GPIO_ACTIVE_LOW : 0);
/* Generic property list is not supported */
acpi_dp_write(ctx, dsd);
}
/* Power Resource */
if (priv->has_power_resource) {
ret = acpi_device_add_power_res(ctx, tx_state_val,
"\\_SB.GPC0", "\\_SB.SPC0",
&priv->reset_gpio, priv->reset_delay_ms,
priv->reset_off_delay_ms, &priv->enable_gpio,
priv->enable_delay_ms, priv->enable_off_delay_ms,
&priv->stop_gpio, priv->stop_delay_ms,
priv->stop_off_delay_ms);
if (ret)
return log_msg_ret("power", ret);
}
if (priv->hid_desc_reg_offset) {
ret = acpi_device_write_dsm_i2c_hid(ctx,
priv->hid_desc_reg_offset);
if (ret)
return log_msg_ret("dsm", ret);
}
acpigen_pop_len(ctx); /* Device */
acpigen_pop_len(ctx); /* Scope */
return 0;
}
int acpi_i2c_ofdata_to_platdata(struct udevice *dev)
{
struct acpi_i2c_priv *priv = dev_get_priv(dev);
gpio_request_by_name(dev, "reset-gpios", 0, &priv->reset_gpio,
GPIOD_IS_OUT);
gpio_request_by_name(dev, "enable-gpios", 0, &priv->enable_gpio,
GPIOD_IS_OUT);
gpio_request_by_name(dev, "irq-gpios", 0, &priv->irq_gpio, GPIOD_IS_IN);
gpio_request_by_name(dev, "stop-gpios", 0, &priv->stop_gpio,
GPIOD_IS_OUT);
irq_get_by_index(dev, 0, &priv->irq);
priv->hid = dev_read_string(dev, "acpi,hid");
if (!priv->hid)
return log_msg_ret("hid", -EINVAL);
dev_read_u32(dev, "acpi,uid", &priv->uid);
priv->desc = dev_read_string(dev, "acpi,ddn");
dev_read_u32(dev, "acpi,wake", &priv->wake);
priv->probed = dev_read_bool(dev, "linux,probed");
priv->compat_string = dev_read_string(dev, "acpi,compatible");
priv->has_power_resource = dev_read_bool(dev,
"acpi,has-power-resource");
dev_read_u32(dev, "hid-descr-addr", &priv->hid_desc_reg_offset);
dev_read_u32(dev, "reset-delay-ms", &priv->reset_delay_ms);
dev_read_u32(dev, "reset-off-delay-ms", &priv->reset_off_delay_ms);
dev_read_u32(dev, "enable-delay-ms", &priv->enable_delay_ms);
dev_read_u32(dev, "enable-off-delay-ms", &priv->enable_off_delay_ms);
dev_read_u32(dev, "stop-delay-ms", &priv->stop_delay_ms);
dev_read_u32(dev, "stop-off-delay-ms", &priv->stop_off_delay_ms);
return 0;
}
/* Use name specified in priv or build one from I2C address */
static int acpi_i2c_get_name(const struct udevice *dev, char *out_name)
{
struct dm_i2c_chip *chip = dev_get_parent_platdata(dev);
struct acpi_i2c_priv *priv = dev_get_priv(dev);
snprintf(out_name, ACPI_NAME_MAX,
priv->hid_desc_reg_offset ? "H%03X" : "D%03X",
chip->chip_addr);
return 0;
}
struct acpi_ops acpi_i2c_ops = {
.fill_ssdt = acpi_i2c_fill_ssdt,
.get_name = acpi_i2c_get_name,
};