diff options
| -rw-r--r-- | Documentation/acpi/gpio.md | 19 | ||||
| -rw-r--r-- | src/arch/x86/acpi_device.c | 10 | ||||
| -rw-r--r-- | src/arch/x86/acpigen.c | 23 | ||||
| -rw-r--r-- | src/arch/x86/include/arch/acpigen.h | 11 |
4 files changed, 57 insertions, 6 deletions
diff --git a/Documentation/acpi/gpio.md b/Documentation/acpi/gpio.md index 2c09148164..2fb2d1d5a0 100644 --- a/Documentation/acpi/gpio.md +++ b/Documentation/acpi/gpio.md @@ -3,6 +3,7 @@ # Table of contents # - Introduction - Platform Interface +- Helper routines - Implementation details - Arguments and Local Variables Management @@ -55,6 +56,23 @@ adding them as AML code callbacks for the following reasons: 3. Allows GPIO AML methods to be present under any device scope and gives SoC the flexibility to call them without any restrictions. +# Helper routines # + +In order to relieve drivers of the task of implementing the same code +for enabling/disabling Tx GPIOs based on the GPIO polarity, helper +routines are provided which implement this common code and can be used +directly in the driver routines: +1. Enable Tx GPIO + int acpigen_enable_tx_gpio(struct acpi_gpio gpio) +2. Disable Tx GPIO + int acpigen_disable_tx_gpio(struct acpi_gpio gpio) + +Both the above functions take as input struct acpi_gpio type and +return -1 on error and 0 on success. These helper routines end up +calling the platform specific acpigen_soc_{set,clear}_tx_gpio +functions internally. Thus, all the ACPI AML calling conventions for +the platform functions apply to these helper functions as well. + # Implementation Details # ACPI library in coreboot will provide weak definitions for all the @@ -84,7 +102,6 @@ variables. acpigen_soc_clear_tx_gpio Generate ACPI AML code to Error = -1 set Tx to 0. Success = 0 - Ideally, the operation column in the above table should use one or more functions implemented by the platform in AML code library (like gpiolib.asl). In the example below SPC0 and GPC0 need to be diff --git a/src/arch/x86/acpi_device.c b/src/arch/x86/acpi_device.c index 323d4f1eab..42305a6ab4 100644 --- a/src/arch/x86/acpi_device.c +++ b/src/arch/x86/acpi_device.c @@ -512,14 +512,14 @@ void acpi_device_add_power_res( /* Method (_ON, 0, Serialized) */ acpigen_write_method_serialized("_ON", 0); if (reset_gpio) - acpigen_soc_set_tx_gpio(reset_gpio); + acpigen_enable_tx_gpio(reset); if (enable_gpio) { - acpigen_soc_set_tx_gpio(enable_gpio); + acpigen_enable_tx_gpio(enable); if (enable_delay_ms) acpigen_write_sleep(enable_delay_ms); } if (reset_gpio) { - acpigen_soc_clear_tx_gpio(reset_gpio); + acpigen_disable_tx_gpio(reset); if (reset_delay_ms) acpigen_write_sleep(reset_delay_ms); } @@ -528,9 +528,9 @@ void acpi_device_add_power_res( /* Method (_OFF, 0, Serialized) */ acpigen_write_method_serialized("_OFF", 0); if (reset_gpio) - acpigen_soc_set_tx_gpio(reset_gpio); + acpigen_enable_tx_gpio(reset); if (enable_gpio) - acpigen_soc_clear_tx_gpio(enable_gpio); + acpigen_disable_tx_gpio(enable); acpigen_pop_len(); /* _OFF method */ acpigen_pop_len(); /* PowerResource PRIC */ diff --git a/src/arch/x86/acpigen.c b/src/arch/x86/acpigen.c index 8ebdd0982c..d3ec05fe3d 100644 --- a/src/arch/x86/acpigen.c +++ b/src/arch/x86/acpigen.c @@ -1299,3 +1299,26 @@ int __attribute__((weak)) acpigen_soc_clear_tx_gpio(unsigned int gpio_num) acpigen_write_debug_string("clear_tx_gpio not available"); return -1; } + +/* + * Helper functions for enabling/disabling Tx GPIOs based on the GPIO + * polarity. These functions end up calling acpigen_soc_{set,clear}_tx_gpio to + * make callbacks into SoC acpigen code. + * + * Returns 0 on success and -1 on error. + */ +int acpigen_enable_tx_gpio(struct acpi_gpio *gpio) +{ + if (gpio->polarity == ACPI_GPIO_ACTIVE_HIGH) + return acpigen_soc_set_tx_gpio(gpio->pins[0]); + else + return acpigen_soc_clear_tx_gpio(gpio->pins[0]); +} + +int acpigen_disable_tx_gpio(struct acpi_gpio *gpio) +{ + if (gpio->polarity == ACPI_GPIO_ACTIVE_LOW) + return acpigen_soc_set_tx_gpio(gpio->pins[0]); + else + return acpigen_soc_clear_tx_gpio(gpio->pins[0]); +} diff --git a/src/arch/x86/include/arch/acpigen.h b/src/arch/x86/include/arch/acpigen.h index f76d85e9bc..c1c4d598c4 100644 --- a/src/arch/x86/include/arch/acpigen.h +++ b/src/arch/x86/include/arch/acpigen.h @@ -21,6 +21,7 @@ #include <stdlib.h> #include <stdint.h> #include <arch/acpi.h> +#include <arch/acpi_device.h> /* Values that can be returned for ACPI Device _STA method */ #define ACPI_STATUS_DEVICE_PRESENT (1 << 0) @@ -289,4 +290,14 @@ int acpigen_soc_set_tx_gpio(unsigned int gpio_num); /* Generate ACPI AML code to set Tx value of GPIO to 0. */ int acpigen_soc_clear_tx_gpio(unsigned int gpio_num); +/* + * Helper functions for enabling/disabling Tx GPIOs based on the GPIO + * polarity. These functions end up calling acpigen_soc_{set,clear}_tx_gpio to + * make callbacks into SoC acpigen code. + * + * Returns 0 on success and -1 on error. + */ +int acpigen_enable_tx_gpio(struct acpi_gpio *gpio); +int acpigen_disable_tx_gpio(struct acpi_gpio *gpio); + #endif |