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This RFC includes the driver, Devicetree binding, and board node to discuss the final kernel-facing interface. Signed-off-by: Prasanth Kumar Padarthi --- .../asrock,b650d4u-power-passthrough.yaml | 23 ++++ .../dts/aspeed/aspeed-bmc-asrock-b650d4u.dts | 5 + drivers/soc/aspeed/Kconfig | 9 ++ drivers/soc/aspeed/Makefile | 1 + drivers/soc/aspeed/aspeed-b650d4u-power.c | 110 ++++++++++++++++++ 5 files changed, 148 insertions(+) create mode 100644 Documentation/devicetree/bindings/soc/aspeed/asrock,b650d4u-power-passthrough.yaml create mode 100644 drivers/soc/aspeed/aspeed-b650d4u-power.c diff --git a/Documentation/devicetree/bindings/soc/aspeed/asrock,b650d4u-power-passthrough.yaml b/Documentation/devicetree/bindings/soc/aspeed/asrock,b650d4u-power-passthrough.yaml new file mode 100644 index 000000000000..e6451d17955c --- /dev/null +++ b/Documentation/devicetree/bindings/soc/aspeed/asrock,b650d4u-power-passthrough.yaml @@ -0,0 +1,23 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/soc/aspeed/asrock,b650d4u-power-passthrough.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: ASRock Rack B650D4U power passthrough + +maintainers: + - Prasanth Kumar Padarthi + +properties: + compatible: + const: asrock,b650d4u-power-passthrough + + aspeed,scu: + $ref: /schemas/types.yaml#/definitions/phandle + +required: + - compatible + - aspeed,scu + +additionalProperties: false diff --git a/arch/arm/boot/dts/aspeed/aspeed-bmc-asrock-b650d4u.dts b/arch/arm/boot/dts/aspeed/aspeed-bmc-asrock-b650d4u.dts index a4e384588a54..86291c250562 100644 --- a/arch/arm/boot/dts/aspeed/aspeed-bmc-asrock-b650d4u.dts +++ b/arch/arm/boot/dts/aspeed/aspeed-bmc-asrock-b650d4u.dts @@ -32,6 +32,11 @@ gfx_memory: framebuffer { size = <0x01000000>; }; }; + + host-power-passthrough { + compatible = "asrock,b650d4u-power-passthrough"; + aspeed,scu = <&syscon>; + }; }; &fmc { diff --git a/drivers/soc/aspeed/Kconfig b/drivers/soc/aspeed/Kconfig index 11e4db998c06..1b0281e0bfb0 100644 --- a/drivers/soc/aspeed/Kconfig +++ b/drivers/soc/aspeed/Kconfig @@ -58,6 +58,15 @@ config ASPEED_SBC Say yes to provide information about the secure boot controller in debugfs. +config ASPEED_B650D4U_POWER + tristate "ASRock B650D4U host power passthrough" + select REGMAP + select MFD_SYSCON + default ARCH_ASPEED + help + Enable the AST2600 GPIO passthrough selector used by the + ASRock Rack B650D4U host power-control circuit. This selector routes the host power pulse through the board's passthrough logic during power sequencing. + config ASPEED_XDMA tristate "ASPEED XDMA Engine Driver" select REGMAP diff --git a/drivers/soc/aspeed/Makefile b/drivers/soc/aspeed/Makefile index 5f61bb4cc36c..3e9618d1eafc 100644 --- a/drivers/soc/aspeed/Makefile +++ b/drivers/soc/aspeed/Makefile @@ -5,4 +5,5 @@ obj-$(CONFIG_ASPEED_UART_ROUTING) += aspeed-uart-routing.o obj-$(CONFIG_ASPEED_P2A_CTRL) += aspeed-p2a-ctrl.o obj-$(CONFIG_ASPEED_SOCINFO) += aspeed-socinfo.o obj-$(CONFIG_ASPEED_SBC) += aspeed-sbc.o +obj-$(CONFIG_ASPEED_B650D4U_POWER) += aspeed-b650d4u-power.o obj-$(CONFIG_ASPEED_XDMA) += aspeed-xdma.o diff --git a/drivers/soc/aspeed/aspeed-b650d4u-power.c b/drivers/soc/aspeed/aspeed-b650d4u-power.c new file mode 100644 index 000000000000..22a6925539dc --- /dev/null +++ b/drivers/soc/aspeed/aspeed-b650d4u-power.c @@ -0,0 +1,110 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define ASPEED_SCU_PROTECTION 0x000 +#define ASPEED_SCU_GPIO_PASSTHROUGH 0x4bc +#define ASPEED_SCU_GPIO_ACTION 0x51c +#define ASPEED_SCU_UNLOCK_KEY 0x1688a8a8 +#define ASPEED_B650D4U_POWER_MASK GENMASK(27, 26) + +static struct regmap *b650d4u_scu; +static DEFINE_MUTEX(b650d4u_lock); + +static int b650d4u_set_passthrough(bool enable) +{ + int ret; + + mutex_lock(&b650d4u_lock); + + ret = regmap_write(b650d4u_scu, ASPEED_SCU_PROTECTION, + ASPEED_SCU_UNLOCK_KEY); + if (ret) { + pr_err("B650D4U: SCU unlock failed: %d\n", ret); + goto out; + } + + ret = regmap_update_bits(b650d4u_scu, + ASPEED_SCU_GPIO_PASSTHROUGH, + ASPEED_B650D4U_POWER_MASK, + enable ? ASPEED_B650D4U_POWER_MASK : 0); + if (ret) { + pr_err("B650D4U: passthrough update failed: %d\n", ret); + goto out; + } + + if (!enable) + ret = regmap_write(b650d4u_scu, + ASPEED_SCU_GPIO_ACTION, 0); + +out: + mutex_unlock(&b650d4u_lock); + return ret; +} + +static ssize_t passthrough_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + bool enable; + int ret; + + ret = kstrtobool(buf, &enable); + if (ret) + return ret; + + ret = b650d4u_set_passthrough(enable); + return ret ? ret : count; +} +static DEVICE_ATTR_WO(passthrough); + +static int aspeed_b650d4u_power_probe(struct platform_device *pdev) +{ + int ret; + + b650d4u_scu = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, + "aspeed,scu"); + if (IS_ERR(b650d4u_scu)) + return dev_err_probe(&pdev->dev, PTR_ERR(b650d4u_scu), + "failed to get AST2600 SCU regmap\n"); + + ret = b650d4u_set_passthrough(true); + if (ret) + return dev_err_probe(&pdev->dev, ret, + "failed to enable power GPIO passthrough\n"); + + ret = device_create_file(&pdev->dev, &dev_attr_passthrough); + if (ret) + return dev_err_probe(&pdev->dev, ret, + "failed to create passthrough control\n"); + + dev_info(&pdev->dev, "enabled GPIO passthrough selector 1\n"); + return 0; +} + +static const struct of_device_id aspeed_b650d4u_power_of_match[] = { + { .compatible = "asrock,b650d4u-power-passthrough" }, + { } +}; +MODULE_DEVICE_TABLE(of, aspeed_b650d4u_power_of_match); + +static struct platform_driver aspeed_b650d4u_power_driver = { + .probe = aspeed_b650d4u_power_probe, + .driver = { + .name = "aspeed-b650d4u-power", + .of_match_table = aspeed_b650d4u_power_of_match, + }, +}; +module_platform_driver(aspeed_b650d4u_power_driver); + +MODULE_DESCRIPTION("ASRock Rack B650D4U host power GPIO passthrough"); +MODULE_LICENSE("GPL"); -- 2.47.3