drivers/i2c/generic: Allow mainboards to export reset and enable GPIOs

Add power management type config option that allows mainboards to
either:
1. Define a power resource that uses the reset and enable gpios to
power on and off the device using _ON and _OFF methods, or
2. Export reset and enable GPIOs in _CRS and _DSD so that the OS can
directly toggle the GPIOs as required.

GPIO type needs to be updated in drivers_i2c_generic_config to use
acpi_gpio type so that it can be used for both the above cases.

BUG=chrome-os-partner:60194
BRANCH=None
TEST=Verified that elan touchscreen works fine on reef using exported
GPIOs.

Change-Id: I4d76f193f615cfc4520869dedc55505c109042f6
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/17797
Tested-by: build bot (Jenkins)
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
This commit is contained in:
Furquan Shaikh 2016-12-12 09:23:01 -08:00 committed by Martin Roth
parent c804826be9
commit 98915bb7a9
3 changed files with 74 additions and 20 deletions

View File

@ -19,6 +19,11 @@
#include <arch/acpi_device.h>
#include <device/i2c.h>
enum power_mgmt_type {
POWER_RESOURCE = 1,
GPIO_EXPORT = 2,
};
struct drivers_i2c_generic_config {
const char *hid; /* ACPI _HID (required) */
const char *cid; /* ACPI _CID */
@ -42,12 +47,15 @@ struct drivers_i2c_generic_config {
unsigned device_present_gpio;
unsigned device_present_gpio_invert;
/* Power management type. */
enum power_mgmt_type pwr_mgmt_type;
/* GPIO used to take device out of reset or to put it into reset. */
unsigned reset_gpio;
struct acpi_gpio reset_gpio;
/* Delay to be inserted after device is taken out of reset. */
unsigned reset_delay_ms;
/* GPIO used to enable device. */
unsigned enable_gpio;
struct acpi_gpio enable_gpio;
/* Delay to be inserted after device is enabled. */
unsigned enable_delay_ms;
};

View File

@ -29,8 +29,13 @@
static void i2c_generic_add_power_res(struct drivers_i2c_generic_config *config)
{
const char *power_res_dev_states[] = { "_PR0", "_PR3" };
unsigned reset_gpio = config->reset_gpio.pins[0];
unsigned enable_gpio = config->enable_gpio.pins[0];
if (!config->reset_gpio && !config->enable_gpio)
if (config->pwr_mgmt_type != POWER_RESOURCE)
return;
if (!reset_gpio && !enable_gpio)
return;
/* PowerResource (PRIC, 0, 0) */
@ -42,29 +47,51 @@ static void i2c_generic_add_power_res(struct drivers_i2c_generic_config *config)
/* Method (_ON, 0, Serialized) */
acpigen_write_method_serialized("_ON", 0);
if (config->reset_gpio)
acpigen_soc_set_tx_gpio(config->reset_gpio);
if (config->enable_gpio) {
acpigen_soc_set_tx_gpio(config->enable_gpio);
if (reset_gpio)
acpigen_soc_set_tx_gpio(reset_gpio);
if (enable_gpio) {
acpigen_soc_set_tx_gpio(enable_gpio);
acpigen_write_sleep(config->enable_delay_ms);
}
if (config->reset_gpio) {
acpigen_soc_clear_tx_gpio(config->reset_gpio);
if (reset_gpio) {
acpigen_soc_clear_tx_gpio(reset_gpio);
acpigen_write_sleep(config->reset_delay_ms);
}
acpigen_pop_len(); /* _ON method */
/* Method (_OFF, 0, Serialized) */
acpigen_write_method_serialized("_OFF", 0);
if (config->reset_gpio)
acpigen_soc_set_tx_gpio(config->reset_gpio);
if (config->enable_gpio)
acpigen_soc_clear_tx_gpio(config->enable_gpio);
if (reset_gpio)
acpigen_soc_set_tx_gpio(reset_gpio);
if (enable_gpio)
acpigen_soc_clear_tx_gpio(enable_gpio);
acpigen_pop_len(); /* _OFF method */
acpigen_pop_len(); /* PowerResource PRIC */
}
static bool i2c_generic_add_gpios_to_crs(struct drivers_i2c_generic_config *cfg)
{
if (cfg->pwr_mgmt_type == GPIO_EXPORT)
return true;
return false;
}
static int i2c_generic_write_gpio(struct acpi_gpio *gpio, int *curr_index)
{
int ret = -1;
if (gpio->pin_count == 0)
return ret;
acpi_device_write_gpio(gpio);
ret = *curr_index;
(*curr_index)++;
return ret;
}
void i2c_generic_fill_ssdt(struct device *dev,
void (*callback)(struct device *dev),
struct drivers_i2c_generic_config *config)
@ -77,6 +104,9 @@ void i2c_generic_fill_ssdt(struct device *dev,
.resource = scope,
};
struct acpi_dp *dsd = NULL;
int curr_index = 0;
int reset_gpio_index = -1, enable_gpio_index = -1;
const char *path = acpi_device_path(dev);
if (!dev->enabled || !scope)
return;
@ -101,6 +131,12 @@ void i2c_generic_fill_ssdt(struct device *dev,
acpigen_write_resourcetemplate_header();
acpi_device_write_i2c(&i2c);
acpi_device_write_interrupt(&config->irq);
if (i2c_generic_add_gpios_to_crs(config) == true) {
reset_gpio_index = i2c_generic_write_gpio(&config->reset_gpio,
&curr_index);
enable_gpio_index = i2c_generic_write_gpio(&config->enable_gpio,
&curr_index);
}
acpigen_write_resourcetemplate_footer();
/* Wake capabilities */
@ -109,9 +145,20 @@ void i2c_generic_fill_ssdt(struct device *dev,
acpigen_write_PRW(config->wake, 3);
}
if (config->probed) {
/* DSD */
if (config->probed || (reset_gpio_index != -1) ||
(enable_gpio_index != -1)) {
dsd = acpi_dp_new_table("_DSD");
acpi_dp_add_integer(dsd, "linux,probed", 1);
if (config->probed)
acpi_dp_add_integer(dsd, "linux,probed", 1);
if (reset_gpio_index != -1)
acpi_dp_add_gpio(dsd, "reset-gpios", path,
reset_gpio_index, 0,
config->reset_gpio.polarity);
if (enable_gpio_index != -1)
acpi_dp_add_gpio(dsd, "enable-gpios", path,
enable_gpio_index, 0,
config->enable_gpio.polarity);
acpi_dp_write(dsd);
}
@ -125,7 +172,7 @@ void i2c_generic_fill_ssdt(struct device *dev,
acpigen_pop_len(); /* Device */
acpigen_pop_len(); /* Scope */
printk(BIOS_INFO, "%s: %s at %s\n", acpi_device_path(dev),
printk(BIOS_INFO, "%s: %s at %s\n", path,
config->desc ? : dev->chip_ops->name, dev_path(dev));
}

View File

@ -177,10 +177,9 @@ chip soc/intel/apollolake
register "desc" = ""ELAN Touchscreen""
register "irq" = "IRQ_EDGE_LOW(GPIO_21_IRQ)"
register "probed" = "1"
register "reset_gpio" = "GPIO_36"
register "reset_delay_ms" = "20"
register "enable_gpio" = "GPIO_152"
register "enable_delay_ms" = "1"
register "pwr_mgmt_type" = "GPIO_EXPORT"
register "reset_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_HIGH(GPIO_36)"
register "enable_gpio" = "ACPI_GPIO_OUTPUT_ACTIVE_HIGH(GPIO_152)"
device i2c 10 on end
end
end # - I2C 3