This patch supports handling 2 BlueField power states controlled by GPIO interrupts:
1) chip reset and
2) low power mode
This driver is dependent and should be loaded after the gpio-mlxbf2.c driver,
which is the gpio and interrupt controller.
Signed-off-by: Asmaa Mnebhi <asmaa@xxxxxxxxxx>
---
drivers/power/reset/Kconfig | 6 ++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/pwr-mlxbf.c | 100 ++++++++++++++++++++++++++++++++
3 files changed, 107 insertions(+)
create mode 100644 drivers/power/reset/pwr-mlxbf.c
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index 4b563db3ab3e..a8c46ba5878f 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -297,4 +297,10 @@ config NVMEM_REBOOT_MODE
then the bootloader can read it and take different
action according to the mode.
+config POWER_MLXBF
+ tristate "Mellanox BlueField power handling driver"
+ depends on (GPIO_MLXBF2 && ACPI)
+ help
+ This driver supports reset or low power mode handling for Mellanox BlueField.
+
endif
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index f606a2f60539..0a39424fc558 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -35,3 +35,4 @@ obj-$(CONFIG_REBOOT_MODE) += reboot-mode.o
obj-$(CONFIG_SYSCON_REBOOT_MODE) += syscon-reboot-mode.o
obj-$(CONFIG_POWER_RESET_SC27XX) += sc27xx-poweroff.o
obj-$(CONFIG_NVMEM_REBOOT_MODE) += nvmem-reboot-mode.o
+obj-$(CONFIG_POWER_MLXBF) += pwr-mlxbf.o
diff --git a/drivers/power/reset/pwr-mlxbf.c b/drivers/power/reset/pwr-mlxbf.c
new file mode 100644
index 000000000000..30b3ba13be75
--- /dev/null
+++ b/drivers/power/reset/pwr-mlxbf.c
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-2.0-only or BSD-3-Clause
+
+/*
+ * Copyright (c) 2022 NVIDIA CORPORATION & AFFILIATES.
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/reboot.h>
+#include <linux/types.h>
+
+const char *rst_pwr_hid = "MLNXBF24";
+const char *low_pwr_hid = "MLNXBF29";
+
+struct pwr_mlxbf {
+ struct work_struct send_work;
+ const char *hid;
+};
+
+static void pwr_mlxbf_send_work(struct work_struct *work)
+{
+ acpi_bus_generate_netlink_event("button/power.*", "Power Button", 0x80, 1);
+}
+
+static irqreturn_t pwr_mlxbf_irq(int irq, void *ptr)
+{
+ struct pwr_mlxbf *priv = ptr;
+
+ if (!strncmp(priv->hid, rst_pwr_hid, 8))
+ emergency_restart();
+
+ if (!strncmp(priv->hid, low_pwr_hid, 8))
+ schedule_work(&priv->send_work);
+
+ return IRQ_HANDLED;
+}
+
+static int
+pwr_mlxbf_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct acpi_device *adev;
+ struct pwr_mlxbf *priv;
+ const char *hid;
+ int irq, err;
+
+ priv = devm_kzalloc(dev, sizeof(struct pwr_mlxbf), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ adev = ACPI_COMPANION(dev);
+ if (!adev)
+ return -ENXIO;
+
+ hid = acpi_device_hid(adev);
+ priv->hid = hid;
+
+ irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(&pdev->dev), 0);
+ if (irq == -EPROBE_DEFER) {
+ return -EPROBE_DEFER;
+ } else if (irq < 0) {
+ dev_err(&pdev->dev, "Error getting %s irq.\n", priv->hid);
+ return -ENXIO;
+ }
+
+ INIT_WORK(&priv->send_work, pwr_mlxbf_send_work);
+
+ err = devm_request_irq(&pdev->dev, irq, pwr_mlxbf_irq, 0, hid, priv);
+ if (err)
+ dev_err(&pdev->dev, "Failed request of %s irq\n", priv->hid);
+
+ return err;
+}
+
+static const struct acpi_device_id __maybe_unused pwr_mlxbf_acpi_match[] = {
+ { "MLNXBF24", 0 },
+ { "MLNXBF29", 0 },
+ {},
+};
+MODULE_DEVICE_TABLE(acpi, pwr_mlxbf_acpi_match);
+
+static struct platform_driver pwr_mlxbf_driver = {
+ .driver = {
+ .name = "pwr_mlxbf",
+ .acpi_match_table = pwr_mlxbf_acpi_match,
+ },
+ .probe = pwr_mlxbf_probe,
+};
+
+module_platform_driver(pwr_mlxbf_driver);
+
+MODULE_DESCRIPTION("Mellanox BlueField power driver");
+MODULE_AUTHOR("Asmaa Mnebhi <asmaa@xxxxxxxxxx>");
+MODULE_LICENSE("Dual BSD/GPL");
--
2.30.1
