Resguardo inicial

linux-7.2.3/drivers/platform/cznic/Kconfig

@@ -0,0 +1,98 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# For a description of the syntax of this configuration file,
+# see Documentation/kbuild/kconfig-language.rst.
+#
+
+menuconfig CZNIC_PLATFORMS
+	bool "Platform support for CZ.NIC's Turris hardware"
+	depends on ARCH_MVEBU || COMPILE_TEST
+	help
+	  Say Y here to be able to choose driver support for CZ.NIC's Turris
+	  devices. This option alone does not add any kernel code.
+
+if CZNIC_PLATFORMS
+
+config TURRIS_OMNIA_MCU
+	tristate "Turris Omnia MCU driver"
+	depends on MACH_ARMADA_38X || COMPILE_TEST
+	depends on I2C
+	help
+	  Say Y here to add support for the features implemented by the
+	  microcontroller on the CZ.NIC's Turris Omnia SOHO router.
+	  This option only enables the core part of the driver. Specific
+	  features can be enabled by subsequent config options.
+	  To compile this driver as a module, choose M here; the module will be
+	  called turris-omnia-mcu.
+
+if TURRIS_OMNIA_MCU
+
+config TURRIS_OMNIA_MCU_GPIO
+	bool "Turris Omnia MCU GPIOs"
+	default y
+	depends on GPIOLIB
+	depends on OF
+	select GPIOLIB_IRQCHIP
+	help
+	  Say Y here to add support for controlling MCU GPIO pins and receiving
+	  MCU interrupts on CZ.NIC's Turris Omnia.
+	  This enables you to
+	  - get front button press events (the front button can be configured
+	    either to generate press events to the CPU or to change front LEDs
+	    panel brightness),
+	  - enable / disable USB port voltage regulators and to detect USB
+	    overcurrent,
+	  - detect MiniPCIe / mSATA card presence in MiniPCIe port 0,
+	  - configure resets of various peripherals on board revisions 32+,
+	  - enable / disable the VHV voltage regulator to the SOC in order to be
+	    able to program SOC's OTP on board revisions 32+,
+	  - get input from the LED output pins of the WAN ethernet PHY, LAN
+	    switch and MiniPCIe ports.
+
+config TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
+	bool "Turris Omnia MCU system off and RTC wakeup"
+	default y
+	depends on RTC_CLASS
+	help
+	  Say Y here to add support for CZ.NIC's Turris Omnia board poweroff
+	  into true low power mode (with voltage regulators disabled) and the
+	  ability to configure wake up from this mode (via rtcwake).
+
+config TURRIS_OMNIA_MCU_WATCHDOG
+	bool "Turris Omnia MCU watchdog"
+	default y
+	depends on WATCHDOG
+	select WATCHDOG_CORE
+	help
+	  Say Y here to add support for watchdog provided by CZ.NIC's Turris
+	  Omnia MCU.
+
+config TURRIS_OMNIA_MCU_TRNG
+	bool "Turris Omnia MCU true random number generator"
+	default y
+	depends on TURRIS_OMNIA_MCU_GPIO
+	depends on HW_RANDOM=y || HW_RANDOM=TURRIS_OMNIA_MCU
+	help
+	  Say Y here to add support for the true random number generator
+	  provided by CZ.NIC's Turris Omnia MCU.
+
+config TURRIS_OMNIA_MCU_KEYCTL
+	bool "Turris Omnia MCU ECDSA message signing"
+	default y
+	depends on KEYS
+	depends on ASYMMETRIC_KEY_TYPE
+	depends on TURRIS_OMNIA_MCU_GPIO
+	select TURRIS_SIGNING_KEY
+	help
+	  Say Y here to add support for ECDSA message signing with board private
+	  key (if available on the MCU). This is exposed via the keyctl()
+	  syscall.
+
+endif # TURRIS_OMNIA_MCU
+
+config TURRIS_SIGNING_KEY
+	tristate
+	depends on KEYS
+	depends on ASYMMETRIC_KEY_TYPE
+
+endif # CZNIC_PLATFORMS

linux-7.2.3/drivers/platform/cznic/Makefile

@@ -0,0 +1,11 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-$(CONFIG_TURRIS_OMNIA_MCU)	+= turris-omnia-mcu.o
+turris-omnia-mcu-y		:= turris-omnia-mcu-base.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_GPIO)		+= turris-omnia-mcu-gpio.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_KEYCTL)		+= turris-omnia-mcu-keyctl.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP)	+= turris-omnia-mcu-sys-off-wakeup.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_TRNG)		+= turris-omnia-mcu-trng.o
+turris-omnia-mcu-$(CONFIG_TURRIS_OMNIA_MCU_WATCHDOG)		+= turris-omnia-mcu-watchdog.o
+
+obj-$(CONFIG_TURRIS_SIGNING_KEY) += turris-signing-key.o

linux-7.2.3/drivers/platform/cznic/turris-omnia-mcu-base.c

@@ -0,0 +1,419 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CZ.NIC's Turris Omnia MCU driver
+ *
+ * 2024 by Marek Behún <kabel@kernel.org>
+ */
+
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/hex.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include <linux/turris-omnia-mcu-interface.h>
+#include "turris-omnia-mcu.h"
+
+#define OMNIA_FW_VERSION_LEN		20
+#define OMNIA_FW_VERSION_HEX_LEN	(2 * OMNIA_FW_VERSION_LEN + 1)
+#define OMNIA_BOARD_INFO_LEN		16
+
+int omnia_cmd_write_read(const struct i2c_client *client,
+			 void *cmd, unsigned int cmd_len,
+			 void *reply, unsigned int reply_len)
+{
+	struct i2c_msg msgs[2];
+	int ret, num;
+
+	msgs[0].addr = client->addr;
+	msgs[0].flags = 0;
+	msgs[0].len = cmd_len;
+	msgs[0].buf = cmd;
+	num = 1;
+
+	if (reply_len) {
+		msgs[1].addr = client->addr;
+		msgs[1].flags = I2C_M_RD;
+		msgs[1].len = reply_len;
+		msgs[1].buf = reply;
+		num++;
+	}
+
+	ret = i2c_transfer(client->adapter, msgs, num);
+	if (ret < 0)
+		return ret;
+	if (ret != num)
+		return -EIO;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(omnia_cmd_write_read);
+
+static int omnia_get_version_hash(struct omnia_mcu *mcu, bool bootloader,
+				  char version[static OMNIA_FW_VERSION_HEX_LEN])
+{
+	u8 reply[OMNIA_FW_VERSION_LEN];
+	char *p;
+	int err;
+
+	err = omnia_cmd_read(mcu->client,
+			     bootloader ? OMNIA_CMD_GET_FW_VERSION_BOOT
+					: OMNIA_CMD_GET_FW_VERSION_APP,
+			     reply, sizeof(reply));
+	if (err)
+		return err;
+
+	p = bin2hex(version, reply, OMNIA_FW_VERSION_LEN);
+	*p = '\0';
+
+	return 0;
+}
+
+static ssize_t fw_version_hash_show(struct device *dev, char *buf,
+				    bool bootloader)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+	char version[OMNIA_FW_VERSION_HEX_LEN];
+	int err;
+
+	err = omnia_get_version_hash(mcu, bootloader, version);
+	if (err)
+		return err;
+
+	return sysfs_emit(buf, "%s\n", version);
+}
+
+static ssize_t fw_version_hash_application_show(struct device *dev,
+						struct device_attribute *a,
+						char *buf)
+{
+	return fw_version_hash_show(dev, buf, false);
+}
+static DEVICE_ATTR_RO(fw_version_hash_application);
+
+static ssize_t fw_version_hash_bootloader_show(struct device *dev,
+					       struct device_attribute *a,
+					       char *buf)
+{
+	return fw_version_hash_show(dev, buf, true);
+}
+static DEVICE_ATTR_RO(fw_version_hash_bootloader);
+
+static ssize_t fw_features_show(struct device *dev, struct device_attribute *a,
+				char *buf)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "0x%x\n", mcu->features);
+}
+static DEVICE_ATTR_RO(fw_features);
+
+static ssize_t mcu_type_show(struct device *dev, struct device_attribute *a,
+			     char *buf)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%s\n", mcu->type);
+}
+static DEVICE_ATTR_RO(mcu_type);
+
+static ssize_t reset_selector_show(struct device *dev,
+				   struct device_attribute *a, char *buf)
+{
+	u8 reply;
+	int err;
+
+	err = omnia_cmd_read_u8(to_i2c_client(dev), OMNIA_CMD_GET_RESET,
+				&reply);
+	if (err)
+		return err;
+
+	return sysfs_emit(buf, "%d\n", reply);
+}
+static DEVICE_ATTR_RO(reset_selector);
+
+static ssize_t serial_number_show(struct device *dev,
+				  struct device_attribute *a, char *buf)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%016llX\n", mcu->board_serial_number);
+}
+static DEVICE_ATTR_RO(serial_number);
+
+static ssize_t first_mac_address_show(struct device *dev,
+				      struct device_attribute *a, char *buf)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%pM\n", mcu->board_first_mac);
+}
+static DEVICE_ATTR_RO(first_mac_address);
+
+static ssize_t board_revision_show(struct device *dev,
+				   struct device_attribute *a, char *buf)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%u\n", mcu->board_revision);
+}
+static DEVICE_ATTR_RO(board_revision);
+
+static struct attribute *omnia_mcu_base_attrs[] = {
+	&dev_attr_fw_version_hash_application.attr,
+	&dev_attr_fw_version_hash_bootloader.attr,
+	&dev_attr_fw_features.attr,
+	&dev_attr_mcu_type.attr,
+	&dev_attr_reset_selector.attr,
+	&dev_attr_serial_number.attr,
+	&dev_attr_first_mac_address.attr,
+	&dev_attr_board_revision.attr,
+	NULL
+};
+
+static umode_t omnia_mcu_base_attrs_visible(struct kobject *kobj,
+					    struct attribute *a, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+
+	if ((a == &dev_attr_serial_number.attr ||
+	     a == &dev_attr_first_mac_address.attr ||
+	     a == &dev_attr_board_revision.attr) &&
+	    !(mcu->features & OMNIA_FEAT_BOARD_INFO))
+		return 0;
+
+	return a->mode;
+}
+
+static const struct attribute_group omnia_mcu_base_group = {
+	.attrs = omnia_mcu_base_attrs,
+	.is_visible = omnia_mcu_base_attrs_visible,
+};
+
+static const struct attribute_group *omnia_mcu_groups[] = {
+	&omnia_mcu_base_group,
+#ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO
+	&omnia_mcu_gpio_group,
+#endif
+#ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
+	&omnia_mcu_poweroff_group,
+#endif
+	NULL
+};
+
+static void omnia_mcu_print_version_hash(struct omnia_mcu *mcu, bool bootloader)
+{
+	const char *type = bootloader ? "bootloader" : "application";
+	struct device *dev = &mcu->client->dev;
+	char version[OMNIA_FW_VERSION_HEX_LEN];
+	int err;
+
+	err = omnia_get_version_hash(mcu, bootloader, version);
+	if (err) {
+		dev_err(dev, "Cannot read MCU %s firmware version: %d\n",
+			type, err);
+		return;
+	}
+
+	dev_info(dev, "MCU %s firmware version hash: %s\n", type, version);
+}
+
+static const char *omnia_status_to_mcu_type(u16 status)
+{
+	switch (status & OMNIA_STS_MCU_TYPE_MASK) {
+	case OMNIA_STS_MCU_TYPE_STM32:
+		return "STM32";
+	case OMNIA_STS_MCU_TYPE_GD32:
+		return "GD32";
+	case OMNIA_STS_MCU_TYPE_MKL:
+		return "MKL";
+	default:
+		return "unknown";
+	}
+}
+
+static void omnia_info_missing_feature(struct device *dev, const char *feature)
+{
+	dev_info(dev,
+		 "Your board's MCU firmware does not support the %s feature.\n",
+		 feature);
+}
+
+static int omnia_mcu_read_features(struct omnia_mcu *mcu)
+{
+	static const struct {
+		u16 mask;
+		const char *name;
+	} features[] = {
+#define _DEF_FEAT(_n, _m) { OMNIA_FEAT_ ## _n, _m }
+		_DEF_FEAT(EXT_CMDS,		"extended control and status"),
+		_DEF_FEAT(WDT_PING,		"watchdog pinging"),
+		_DEF_FEAT(LED_STATE_EXT_MASK,	"peripheral LED pins reading"),
+		_DEF_FEAT(NEW_INT_API,		"new interrupt API"),
+		_DEF_FEAT(POWEROFF_WAKEUP,	"poweroff and wakeup"),
+		_DEF_FEAT(TRNG,			"true random number generator"),
+		_DEF_FEAT(BRIGHTNESS_INT,	"LED panel brightness change interrupt"),
+		_DEF_FEAT(LED_GAMMA_CORRECTION,	"LED gamma correction"),
+#undef _DEF_FEAT
+	};
+	struct i2c_client *client = mcu->client;
+	struct device *dev = &client->dev;
+	bool suggest_fw_upgrade = false;
+	u16 status;
+	int err;
+
+	/* status word holds MCU type, which we need below */
+	err = omnia_cmd_read_u16(client, OMNIA_CMD_GET_STATUS_WORD, &status);
+	if (err)
+		return err;
+
+	/*
+	 * Check whether MCU firmware supports the OMNIA_CMD_GET_FEATURES
+	 * command.
+	 */
+	if (status & OMNIA_STS_FEATURES_SUPPORTED) {
+		/* try read 32-bit features */
+		err = omnia_cmd_read_u32(client, OMNIA_CMD_GET_FEATURES,
+					 &mcu->features);
+		if (err) {
+			/* try read 16-bit features */
+			u16 features16;
+
+			err = omnia_cmd_read_u16(client, OMNIA_CMD_GET_FEATURES,
+						 &features16);
+			if (err)
+				return err;
+
+			mcu->features = features16;
+		} else {
+			if (mcu->features & OMNIA_FEAT_FROM_BIT_16_INVALID)
+				mcu->features &= GENMASK(15, 0);
+		}
+	} else {
+		dev_info(dev,
+			 "Your board's MCU firmware does not support feature reading.\n");
+		suggest_fw_upgrade = true;
+	}
+
+	mcu->type = omnia_status_to_mcu_type(status);
+	dev_info(dev, "MCU type %s%s\n", mcu->type,
+		 (mcu->features & OMNIA_FEAT_PERIPH_MCU) ?
+			", with peripheral resets wired" : "");
+
+	omnia_mcu_print_version_hash(mcu, true);
+
+	if (mcu->features & OMNIA_FEAT_BOOTLOADER)
+		dev_warn(dev,
+			 "MCU is running bootloader firmware. Was firmware upgrade interrupted?\n");
+	else
+		omnia_mcu_print_version_hash(mcu, false);
+
+	for (unsigned int i = 0; i < ARRAY_SIZE(features); i++) {
+		if (mcu->features & features[i].mask)
+			continue;
+
+		omnia_info_missing_feature(dev, features[i].name);
+		suggest_fw_upgrade = true;
+	}
+
+	if (suggest_fw_upgrade)
+		dev_info(dev,
+			 "Consider upgrading MCU firmware with the omnia-mcutool utility.\n");
+
+	return 0;
+}
+
+static int omnia_mcu_read_board_info(struct omnia_mcu *mcu)
+{
+	u8 reply[1 + OMNIA_BOARD_INFO_LEN];
+	int err;
+
+	err = omnia_cmd_read(mcu->client, OMNIA_CMD_BOARD_INFO_GET, reply,
+			     sizeof(reply));
+	if (err)
+		return err;
+
+	if (reply[0] != OMNIA_BOARD_INFO_LEN)
+		return -EIO;
+
+	mcu->board_serial_number = get_unaligned_le64(&reply[1]);
+
+	/* we can't use ether_addr_copy() because reply is not u16-aligned */
+	memcpy(mcu->board_first_mac, &reply[9], sizeof(mcu->board_first_mac));
+
+	mcu->board_revision = reply[15];
+
+	return 0;
+}
+
+static int omnia_mcu_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct omnia_mcu *mcu;
+	int err;
+
+	if (!client->irq)
+		return dev_err_probe(dev, -EINVAL, "IRQ resource not found\n");
+
+	mcu = devm_kzalloc(dev, sizeof(*mcu), GFP_KERNEL);
+	if (!mcu)
+		return -ENOMEM;
+
+	mcu->client = client;
+	i2c_set_clientdata(client, mcu);
+
+	err = omnia_mcu_read_features(mcu);
+	if (err)
+		return dev_err_probe(dev, err,
+				     "Cannot determine MCU supported features\n");
+
+	if (mcu->features & OMNIA_FEAT_BOARD_INFO) {
+		err = omnia_mcu_read_board_info(mcu);
+		if (err)
+			return dev_err_probe(dev, err,
+					     "Cannot read board info\n");
+	}
+
+	err = omnia_mcu_register_sys_off_and_wakeup(mcu);
+	if (err)
+		return err;
+
+	err = omnia_mcu_register_watchdog(mcu);
+	if (err)
+		return err;
+
+	err = omnia_mcu_register_gpiochip(mcu);
+	if (err)
+		return err;
+
+	err = omnia_mcu_register_keyctl(mcu);
+	if (err)
+		return err;
+
+	return omnia_mcu_register_trng(mcu);
+}
+
+static const struct of_device_id of_omnia_mcu_match[] = {
+	{ .compatible = "cznic,turris-omnia-mcu" },
+	{}
+};
+
+static struct i2c_driver omnia_mcu_driver = {
+	.probe		= omnia_mcu_probe,
+	.driver		= {
+		.name	= "turris-omnia-mcu",
+		.of_match_table = of_omnia_mcu_match,
+		.dev_groups = omnia_mcu_groups,
+	},
+};
+module_i2c_driver(omnia_mcu_driver);
+
+MODULE_AUTHOR("Marek Behun <kabel@kernel.org>");
+MODULE_DESCRIPTION("CZ.NIC's Turris Omnia MCU");
+MODULE_LICENSE("GPL");

linux-7.2.3/drivers/platform/cznic/turris-omnia-mcu-keyctl.c

@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CZ.NIC's Turris Omnia MCU ECDSA message signing via keyctl
+ *
+ * 2025 by Marek Behún <kabel@kernel.org>
+ */
+
+#include <crypto/sha2.h>
+#include <linux/cleanup.h>
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/key.h>
+#include <linux/mutex.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <linux/turris-omnia-mcu-interface.h>
+#include <linux/turris-signing-key.h>
+#include "turris-omnia-mcu.h"
+
+static irqreturn_t omnia_msg_signed_irq_handler(int irq, void *dev_id)
+{
+	u8 reply[1 + OMNIA_MCU_CRYPTO_SIGNATURE_LEN];
+	struct omnia_mcu *mcu = dev_id;
+	int err;
+
+	err = omnia_cmd_read(mcu->client, OMNIA_CMD_CRYPTO_COLLECT_SIGNATURE,
+			     reply, sizeof(reply));
+	if (!err && reply[0] != OMNIA_MCU_CRYPTO_SIGNATURE_LEN)
+		err = -EIO;
+
+	guard(mutex)(&mcu->sign_lock);
+
+	if (mcu->sign_requested) {
+		mcu->sign_err = err;
+		if (!err)
+			memcpy(mcu->signature, &reply[1],
+			       OMNIA_MCU_CRYPTO_SIGNATURE_LEN);
+		mcu->sign_requested = false;
+		complete(&mcu->msg_signed);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int omnia_mcu_sign(const struct key *key, const void *msg,
+			  void *signature)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(turris_signing_key_get_dev(key));
+	u8 cmd[1 + SHA256_DIGEST_SIZE], reply;
+	int err;
+
+	scoped_guard(mutex, &mcu->sign_lock) {
+		if (mcu->sign_requested)
+			return -EBUSY;
+
+		cmd[0] = OMNIA_CMD_CRYPTO_SIGN_MESSAGE;
+		memcpy(&cmd[1], msg, SHA256_DIGEST_SIZE);
+
+		err = omnia_cmd_write_read(mcu->client, cmd, sizeof(cmd),
+					   &reply, 1);
+		if (err)
+			return err;
+
+		if (!reply)
+			return -EBUSY;
+
+		mcu->sign_requested = true;
+	}
+
+	if (wait_for_completion_interruptible(&mcu->msg_signed))
+		return -EINTR;
+
+	guard(mutex)(&mcu->sign_lock);
+
+	if (mcu->sign_err)
+		return mcu->sign_err;
+
+	memcpy(signature, mcu->signature, OMNIA_MCU_CRYPTO_SIGNATURE_LEN);
+
+	/* forget the signature, for security */
+	memzero_explicit(mcu->signature, sizeof(mcu->signature));
+
+	return OMNIA_MCU_CRYPTO_SIGNATURE_LEN;
+}
+
+static const void *omnia_mcu_get_public_key(const struct key *key)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(turris_signing_key_get_dev(key));
+
+	return mcu->board_public_key;
+}
+
+static const struct turris_signing_key_subtype omnia_signing_key_subtype = {
+	.key_size		= 256,
+	.data_size		= SHA256_DIGEST_SIZE,
+	.sig_size		= OMNIA_MCU_CRYPTO_SIGNATURE_LEN,
+	.public_key_size	= OMNIA_MCU_CRYPTO_PUBLIC_KEY_LEN,
+	.hash_algo		= "sha256",
+	.get_public_key		= omnia_mcu_get_public_key,
+	.sign			= omnia_mcu_sign,
+};
+
+static int omnia_mcu_read_public_key(struct omnia_mcu *mcu)
+{
+	u8 reply[1 + OMNIA_MCU_CRYPTO_PUBLIC_KEY_LEN];
+	int err;
+
+	err = omnia_cmd_read(mcu->client, OMNIA_CMD_CRYPTO_GET_PUBLIC_KEY,
+			     reply, sizeof(reply));
+	if (err)
+		return err;
+
+	if (reply[0] != OMNIA_MCU_CRYPTO_PUBLIC_KEY_LEN)
+		return -EIO;
+
+	memcpy(mcu->board_public_key, &reply[1],
+	       OMNIA_MCU_CRYPTO_PUBLIC_KEY_LEN);
+
+	return 0;
+}
+
+int omnia_mcu_register_keyctl(struct omnia_mcu *mcu)
+{
+	struct device *dev = &mcu->client->dev;
+	char desc[48];
+	int err;
+
+	if (!(mcu->features & OMNIA_FEAT_CRYPTO))
+		return 0;
+
+	err = omnia_mcu_read_public_key(mcu);
+	if (err)
+		return dev_err_probe(dev, err,
+				     "Cannot read board public key\n");
+
+	err = devm_mutex_init(dev, &mcu->sign_lock);
+	if (err)
+		return err;
+
+	init_completion(&mcu->msg_signed);
+
+	err = omnia_mcu_request_irq(mcu, OMNIA_INT_MESSAGE_SIGNED,
+				    omnia_msg_signed_irq_handler,
+				    "turris-omnia-mcu-keyctl");
+	if (err)
+		return dev_err_probe(dev, err,
+				     "Cannot request MESSAGE_SIGNED IRQ\n");
+
+	sprintf(desc, "Turris Omnia SN %016llX MCU ECDSA key",
+		mcu->board_serial_number);
+
+	err = devm_turris_signing_key_create(dev, &omnia_signing_key_subtype,
+					     desc);
+	if (err)
+		return dev_err_probe(dev, err, "Cannot create signing key\n");
+
+	return 0;
+}

linux-7.2.3/drivers/platform/cznic/turris-omnia-mcu-sys-off-wakeup.c

@@ -0,0 +1,260 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CZ.NIC's Turris Omnia MCU system off and RTC wakeup driver
+ *
+ * This is not a true RTC driver (in the sense that it does not provide a
+ * real-time clock), rather the MCU implements a wakeup from powered off state
+ * at a specified time relative to MCU boot, and we expose this feature via RTC
+ * alarm, so that it can be used via the rtcwake command, which is the standard
+ * Linux command for this.
+ *
+ * 2024 by Marek Behún <kabel@kernel.org>
+ */
+
+#include <linux/crc32.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/kstrtox.h>
+#include <linux/reboot.h>
+#include <linux/rtc.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+
+#include <linux/turris-omnia-mcu-interface.h>
+#include "turris-omnia-mcu.h"
+
+static int omnia_get_uptime_wakeup(const struct i2c_client *client, u32 *uptime,
+				   u32 *wakeup)
+{
+	__le32 reply[2];
+	int err;
+
+	err = omnia_cmd_read(client, OMNIA_CMD_GET_UPTIME_AND_WAKEUP, reply,
+			     sizeof(reply));
+	if (err)
+		return err;
+
+	if (uptime)
+		*uptime = le32_to_cpu(reply[0]);
+
+	if (wakeup)
+		*wakeup = le32_to_cpu(reply[1]);
+
+	return 0;
+}
+
+static int omnia_read_time(struct device *dev, struct rtc_time *tm)
+{
+	u32 uptime;
+	int err;
+
+	err = omnia_get_uptime_wakeup(to_i2c_client(dev), &uptime, NULL);
+	if (err)
+		return err;
+
+	rtc_time64_to_tm(uptime, tm);
+
+	return 0;
+}
+
+static int omnia_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct omnia_mcu *mcu = i2c_get_clientdata(client);
+	u32 wakeup;
+	int err;
+
+	err = omnia_get_uptime_wakeup(client, NULL, &wakeup);
+	if (err)
+		return err;
+
+	alrm->enabled = !!wakeup;
+	rtc_time64_to_tm(wakeup ?: mcu->rtc_alarm, &alrm->time);
+
+	return 0;
+}
+
+static int omnia_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct omnia_mcu *mcu = i2c_get_clientdata(client);
+
+	mcu->rtc_alarm = rtc_tm_to_time64(&alrm->time);
+
+	if (alrm->enabled)
+		return omnia_cmd_write_u32(client, OMNIA_CMD_SET_WAKEUP,
+					   mcu->rtc_alarm);
+
+	return 0;
+}
+
+static int omnia_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct omnia_mcu *mcu = i2c_get_clientdata(client);
+
+	return omnia_cmd_write_u32(client, OMNIA_CMD_SET_WAKEUP,
+				   enabled ? mcu->rtc_alarm : 0);
+}
+
+static const struct rtc_class_ops omnia_rtc_ops = {
+	.read_time		= omnia_read_time,
+	.read_alarm		= omnia_read_alarm,
+	.set_alarm		= omnia_set_alarm,
+	.alarm_irq_enable	= omnia_alarm_irq_enable,
+};
+
+static int omnia_power_off(struct sys_off_data *data)
+{
+	struct omnia_mcu *mcu = data->cb_data;
+	__be32 tmp;
+	u8 cmd[9];
+	u16 arg;
+	int err;
+
+	if (mcu->front_button_poweron)
+		arg = OMNIA_CMD_POWER_OFF_POWERON_BUTTON;
+	else
+		arg = 0;
+
+	cmd[0] = OMNIA_CMD_POWER_OFF;
+	put_unaligned_le16(OMNIA_CMD_POWER_OFF_MAGIC, &cmd[1]);
+	put_unaligned_le16(arg, &cmd[3]);
+
+	/*
+	 * Although all values from and to MCU are passed in little-endian, the
+	 * MCU's CRC unit uses big-endian CRC32 polynomial (0x04c11db7), so we
+	 * need to use crc32_be() here.
+	 */
+	tmp = cpu_to_be32(get_unaligned_le32(&cmd[1]));
+	put_unaligned_le32(crc32_be(~0, (void *)&tmp, sizeof(tmp)), &cmd[5]);
+
+	err = omnia_cmd_write(mcu->client, cmd, sizeof(cmd));
+	if (err)
+		dev_err(&mcu->client->dev,
+			"Unable to send the poweroff command: %d\n", err);
+
+	return NOTIFY_DONE;
+}
+
+static int omnia_restart(struct sys_off_data *data)
+{
+	struct omnia_mcu *mcu = data->cb_data;
+	u8 cmd[3];
+	int err;
+
+	cmd[0] = OMNIA_CMD_GENERAL_CONTROL;
+
+	if (reboot_mode == REBOOT_HARD)
+		cmd[1] = cmd[2] = OMNIA_CTL_HARD_RST;
+	else
+		cmd[1] = cmd[2] = OMNIA_CTL_LIGHT_RST;
+
+	err = omnia_cmd_write(mcu->client, cmd, sizeof(cmd));
+	if (err)
+		dev_err(&mcu->client->dev,
+			"Unable to send the restart command: %d\n", err);
+
+	/*
+	 * MCU needs a little bit to process the I2C command, otherwise it will
+	 * do a light reset based on SOC SYSRES_OUT pin.
+	 */
+	mdelay(1);
+
+	return NOTIFY_DONE;
+}
+
+static ssize_t front_button_poweron_show(struct device *dev,
+					 struct device_attribute *a, char *buf)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%d\n", mcu->front_button_poweron);
+}
+
+static ssize_t front_button_poweron_store(struct device *dev,
+					  struct device_attribute *a,
+					  const char *buf, size_t count)
+{
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+	bool val;
+	int err;
+
+	err = kstrtobool(buf, &val);
+	if (err)
+		return err;
+
+	mcu->front_button_poweron = val;
+
+	return count;
+}
+static DEVICE_ATTR_RW(front_button_poweron);
+
+static struct attribute *omnia_mcu_poweroff_attrs[] = {
+	&dev_attr_front_button_poweron.attr,
+	NULL
+};
+
+static umode_t poweroff_attrs_visible(struct kobject *kobj, struct attribute *a,
+				      int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct omnia_mcu *mcu = dev_get_drvdata(dev);
+
+	if (mcu->features & OMNIA_FEAT_POWEROFF_WAKEUP)
+		return a->mode;
+
+	return 0;
+}
+
+const struct attribute_group omnia_mcu_poweroff_group = {
+	.attrs = omnia_mcu_poweroff_attrs,
+	.is_visible = poweroff_attrs_visible,
+};
+
+int omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu *mcu)
+{
+	struct device *dev = &mcu->client->dev;
+	int err;
+
+	/* MCU restart is always available */
+	err = devm_register_sys_off_handler(dev, SYS_OFF_MODE_RESTART,
+					    SYS_OFF_PRIO_FIRMWARE,
+					    omnia_restart, mcu);
+	if (err)
+		return dev_err_probe(dev, err,
+				     "Cannot register system restart handler\n");
+
+	/*
+	 * Poweroff and wakeup are available only if POWEROFF_WAKEUP feature is
+	 * present.
+	 */
+	if (!(mcu->features & OMNIA_FEAT_POWEROFF_WAKEUP))
+		return 0;
+
+	err = devm_register_sys_off_handler(dev, SYS_OFF_MODE_POWER_OFF,
+					    SYS_OFF_PRIO_FIRMWARE,
+					    omnia_power_off, mcu);
+	if (err)
+		return dev_err_probe(dev, err,
+				     "Cannot register system power off handler\n");
+
+	mcu->rtcdev = devm_rtc_allocate_device(dev);
+	if (IS_ERR(mcu->rtcdev))
+		return dev_err_probe(dev, PTR_ERR(mcu->rtcdev),
+				     "Cannot allocate RTC device\n");
+
+	mcu->rtcdev->ops = &omnia_rtc_ops;
+	mcu->rtcdev->range_max = U32_MAX;
+	set_bit(RTC_FEATURE_ALARM_WAKEUP_ONLY, mcu->rtcdev->features);
+
+	err = devm_rtc_register_device(mcu->rtcdev);
+	if (err)
+		return dev_err_probe(dev, err, "Cannot register RTC device\n");
+
+	mcu->front_button_poweron = true;
+
+	return 0;
+}

linux-7.2.3/drivers/platform/cznic/turris-omnia-mcu-trng.c

@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CZ.NIC's Turris Omnia MCU TRNG driver
+ *
+ * 2024 by Marek Behún <kabel@kernel.org>
+ */
+
+#include <linux/completion.h>
+#include <linux/container_of.h>
+#include <linux/errno.h>
+#include <linux/hw_random.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/minmax.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <linux/turris-omnia-mcu-interface.h>
+#include "turris-omnia-mcu.h"
+
+#define OMNIA_CMD_TRNG_MAX_ENTROPY_LEN	64
+
+static irqreturn_t omnia_trng_irq_handler(int irq, void *dev_id)
+{
+	struct omnia_mcu *mcu = dev_id;
+
+	complete(&mcu->trng_entropy_ready);
+
+	return IRQ_HANDLED;
+}
+
+static int omnia_trng_read(struct hwrng *rng, void *data, size_t max, bool wait)
+{
+	struct omnia_mcu *mcu = container_of(rng, struct omnia_mcu, trng);
+	u8 reply[1 + OMNIA_CMD_TRNG_MAX_ENTROPY_LEN];
+	int err, bytes;
+
+	if (!wait && !completion_done(&mcu->trng_entropy_ready))
+		return 0;
+
+	do {
+		if (wait_for_completion_interruptible(&mcu->trng_entropy_ready))
+			return -ERESTARTSYS;
+
+		err = omnia_cmd_read(mcu->client,
+				     OMNIA_CMD_TRNG_COLLECT_ENTROPY,
+				     reply, sizeof(reply));
+		if (err)
+			return err;
+
+		bytes = min3(reply[0], max, OMNIA_CMD_TRNG_MAX_ENTROPY_LEN);
+	} while (wait && !bytes);
+
+	memcpy(data, &reply[1], bytes);
+
+	return bytes;
+}
+
+int omnia_mcu_register_trng(struct omnia_mcu *mcu)
+{
+	struct device *dev = &mcu->client->dev;
+	u8 dummy;
+	int err;
+
+	if (!(mcu->features & OMNIA_FEAT_TRNG))
+		return 0;
+
+	/*
+	 * If someone else cleared the TRNG interrupt but did not read the
+	 * entropy, a new interrupt won't be generated, and entropy collection
+	 * will be stuck. Ensure an interrupt will be generated by executing
+	 * the collect entropy command (and discarding the result).
+	 */
+	err = omnia_cmd_read(mcu->client, OMNIA_CMD_TRNG_COLLECT_ENTROPY,
+			     &dummy, 1);
+	if (err)
+		return err;
+
+	init_completion(&mcu->trng_entropy_ready);
+
+	err = omnia_mcu_request_irq(mcu, OMNIA_INT_TRNG, omnia_trng_irq_handler,
+				    "turris-omnia-mcu-trng");
+	if (err)
+		return dev_err_probe(dev, err, "Cannot request TRNG IRQ\n");
+
+	mcu->trng.name = "turris-omnia-mcu-trng";
+	mcu->trng.read = omnia_trng_read;
+
+	err = devm_hwrng_register(dev, &mcu->trng);
+	if (err)
+		return dev_err_probe(dev, err, "Cannot register TRNG\n");
+
+	return 0;
+}

linux-7.2.3/drivers/platform/cznic/turris-omnia-mcu-watchdog.c

@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * CZ.NIC's Turris Omnia MCU watchdog driver
+ *
+ * 2024 by Marek Behún <kabel@kernel.org>
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/units.h>
+#include <linux/watchdog.h>
+
+#include <linux/turris-omnia-mcu-interface.h>
+#include "turris-omnia-mcu.h"
+
+#define WATCHDOG_TIMEOUT		120
+
+static unsigned int timeout;
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds");
+
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
+			   __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static int omnia_wdt_start(struct watchdog_device *wdt)
+{
+	struct omnia_mcu *mcu = watchdog_get_drvdata(wdt);
+
+	return omnia_cmd_write_u8(mcu->client, OMNIA_CMD_SET_WATCHDOG_STATE, 1);
+}
+
+static int omnia_wdt_stop(struct watchdog_device *wdt)
+{
+	struct omnia_mcu *mcu = watchdog_get_drvdata(wdt);
+
+	return omnia_cmd_write_u8(mcu->client, OMNIA_CMD_SET_WATCHDOG_STATE, 0);
+}
+
+static int omnia_wdt_ping(struct watchdog_device *wdt)
+{
+	struct omnia_mcu *mcu = watchdog_get_drvdata(wdt);
+
+	return omnia_cmd_write_u8(mcu->client, OMNIA_CMD_SET_WATCHDOG_STATE, 1);
+}
+
+static int omnia_wdt_set_timeout(struct watchdog_device *wdt,
+				 unsigned int timeout)
+{
+	struct omnia_mcu *mcu = watchdog_get_drvdata(wdt);
+
+	return omnia_cmd_write_u16(mcu->client, OMNIA_CMD_SET_WDT_TIMEOUT,
+				   timeout * DECI);
+}
+
+static unsigned int omnia_wdt_get_timeleft(struct watchdog_device *wdt)
+{
+	struct omnia_mcu *mcu = watchdog_get_drvdata(wdt);
+	u16 timeleft;
+	int err;
+
+	err = omnia_cmd_read_u16(mcu->client, OMNIA_CMD_GET_WDT_TIMELEFT,
+				 &timeleft);
+	if (err) {
+		dev_err(&mcu->client->dev, "Cannot get watchdog timeleft: %d\n",
+			err);
+		return 0;
+	}
+
+	return timeleft / DECI;
+}
+
+static const struct watchdog_info omnia_wdt_info = {
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+	.identity = "Turris Omnia MCU Watchdog",
+};
+
+static const struct watchdog_ops omnia_wdt_ops = {
+	.owner		= THIS_MODULE,
+	.start		= omnia_wdt_start,
+	.stop		= omnia_wdt_stop,
+	.ping		= omnia_wdt_ping,
+	.set_timeout	= omnia_wdt_set_timeout,
+	.get_timeleft	= omnia_wdt_get_timeleft,
+};
+
+int omnia_mcu_register_watchdog(struct omnia_mcu *mcu)
+{
+	struct device *dev = &mcu->client->dev;
+	u8 state;
+	int err;
+
+	if (!(mcu->features & OMNIA_FEAT_WDT_PING))
+		return 0;
+
+	mcu->wdt.info = &omnia_wdt_info;
+	mcu->wdt.ops = &omnia_wdt_ops;
+	mcu->wdt.parent = dev;
+	mcu->wdt.min_timeout = 1;
+	mcu->wdt.max_timeout = 65535 / DECI;
+
+	mcu->wdt.timeout = WATCHDOG_TIMEOUT;
+	watchdog_init_timeout(&mcu->wdt, timeout, dev);
+
+	watchdog_set_drvdata(&mcu->wdt, mcu);
+
+	omnia_wdt_set_timeout(&mcu->wdt, mcu->wdt.timeout);
+
+	err = omnia_cmd_read_u8(mcu->client, OMNIA_CMD_GET_WATCHDOG_STATE,
+				&state);
+	if (err)
+		return dev_err_probe(dev, err,
+				     "Cannot get MCU watchdog state\n");
+
+	if (state)
+		set_bit(WDOG_HW_RUNNING, &mcu->wdt.status);
+
+	watchdog_set_nowayout(&mcu->wdt, nowayout);
+	watchdog_stop_on_reboot(&mcu->wdt);
+	err = devm_watchdog_register_device(dev, &mcu->wdt);
+	if (err)
+		return dev_err_probe(dev, err,
+				     "Cannot register MCU watchdog\n");
+
+	return 0;
+}

linux-7.2.3/drivers/platform/cznic/turris-omnia-mcu.h

@@ -0,0 +1,163 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * CZ.NIC's Turris Omnia MCU driver
+ *
+ * 2024 by Marek Behún <kabel@kernel.org>
+ */
+
+#ifndef __TURRIS_OMNIA_MCU_H
+#define __TURRIS_OMNIA_MCU_H
+
+#include <linux/completion.h>
+#include <linux/gpio/driver.h>
+#include <linux/hw_random.h>
+#include <linux/if_ether.h>
+#include <linux/interrupt.h>
+#include <linux/mutex.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+#include <linux/workqueue.h>
+
+enum {
+	OMNIA_MCU_CRYPTO_PUBLIC_KEY_LEN	= 1 + 32,
+	OMNIA_MCU_CRYPTO_SIGNATURE_LEN	= 64,
+};
+
+struct i2c_client;
+struct rtc_device;
+
+/**
+ * struct omnia_mcu - driver private data structure
+ * @client:			I2C client
+ * @type:			MCU type (STM32, GD32, MKL, or unknown)
+ * @features:			bitmap of features supported by the MCU firmware
+ * @board_serial_number:	board serial number, if stored in MCU
+ * @board_first_mac:		board first MAC address, if stored in MCU
+ * @board_revision:		board revision, if stored in MCU
+ * @gc:				GPIO chip
+ * @lock:			mutex to protect internal GPIO chip state
+ * @mask:			bitmap of masked IRQs
+ * @rising:			bitmap of rising edge IRQs
+ * @falling:			bitmap of falling edge IRQs
+ * @both:			bitmap of both edges IRQs
+ * @cached:			bitmap of cached IRQ line values (when an IRQ line is configured for
+ *				both edges, we cache the corresponding GPIO values in the IRQ
+ *				handler)
+ * @is_cached:			bitmap of which IRQ line values are cached
+ * @button_release_emul_work:	front button release emulation work, used with old MCU firmware
+ *				versions which did not send button release events, only button press
+ *				events
+ * @last_status:		cached value of the status word, to be compared with new value to
+ *				determine which interrupt events occurred, used with old MCU
+ *				firmware versions which only informed that the status word changed,
+ *				but not which bits of the status word changed
+ * @button_pressed_emul:	the front button is still emulated to be pressed
+ * @rtcdev:			RTC device, does not actually count real-time, the device is only
+ *				used for the RTC alarm mechanism, so that the board can be
+ *				configured to wake up from poweroff state at a specific time
+ * @rtc_alarm:			RTC alarm that was set for the board to wake up on, in MCU time
+ *				(seconds since last MCU reset)
+ * @front_button_poweron:	the front button should power on the device after it is powered off
+ * @wdt:			watchdog driver structure
+ * @trng:			RNG driver structure
+ * @trng_entropy_ready:		RNG entropy ready completion
+ * @msg_signed:			message signed completion
+ * @sign_lock:			mutex to protect message signing state
+ * @sign_requested:		flag indicating that message signing was requested but not completed
+ * @sign_err:			message signing error number, filled in interrupt handler
+ * @signature:			message signing signature, filled in interrupt handler
+ * @board_public_key:		board public key, if stored in MCU
+ */
+struct omnia_mcu {
+	struct i2c_client *client;
+	const char *type;
+	u32 features;
+
+	u64 board_serial_number;
+	u8 board_first_mac[ETH_ALEN];
+	u8 board_revision;
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO
+	struct gpio_chip gc;
+	struct mutex lock;
+	unsigned long mask, rising, falling, both, cached, is_cached;
+	struct delayed_work button_release_emul_work;
+	unsigned long last_status;
+	bool button_pressed_emul;
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
+	struct rtc_device *rtcdev;
+	u32 rtc_alarm;
+	bool front_button_poweron;
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_WATCHDOG
+	struct watchdog_device wdt;
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_TRNG
+	struct hwrng trng;
+	struct completion trng_entropy_ready;
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_KEYCTL
+	struct completion msg_signed;
+	struct mutex sign_lock;
+	bool sign_requested;
+	int sign_err;
+	u8 signature[OMNIA_MCU_CRYPTO_SIGNATURE_LEN];
+	u8 board_public_key[OMNIA_MCU_CRYPTO_PUBLIC_KEY_LEN];
+#endif
+};
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO
+extern const struct attribute_group omnia_mcu_gpio_group;
+int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu);
+int omnia_mcu_request_irq(struct omnia_mcu *mcu, u32 spec,
+			  irq_handler_t thread_fn, const char *devname);
+#else
+static inline int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_KEYCTL
+int omnia_mcu_register_keyctl(struct omnia_mcu *mcu);
+#else
+static inline int omnia_mcu_register_keyctl(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
+extern const struct attribute_group omnia_mcu_poweroff_group;
+int omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu *mcu);
+#else
+static inline int omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_TRNG
+int omnia_mcu_register_trng(struct omnia_mcu *mcu);
+#else
+static inline int omnia_mcu_register_trng(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
+
+#ifdef CONFIG_TURRIS_OMNIA_MCU_WATCHDOG
+int omnia_mcu_register_watchdog(struct omnia_mcu *mcu);
+#else
+static inline int omnia_mcu_register_watchdog(struct omnia_mcu *mcu)
+{
+	return 0;
+}
+#endif
+
+#endif /* __TURRIS_OMNIA_MCU_H */

linux-7.2.3/drivers/platform/cznic/turris-signing-key.c

@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Some of CZ.NIC's Turris devices support signing messages with a per-device unique asymmetric
+ * cryptographic key that was burned into the device at manufacture.
+ *
+ * This helper module exposes this message signing ability via the keyctl() syscall. Upon load, it
+ * creates the `.turris-signing-keys` keyring. A device-specific driver then has to create a signing
+ * key by calling devm_turris_signing_key_create().
+ *
+ * 2025 by Marek Behún <kabel@kernel.org>
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/key-type.h>
+#include <linux/key.h>
+#include <linux/keyctl.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <linux/turris-signing-key.h>
+
+static int turris_signing_key_instantiate(struct key *key,
+					  struct key_preparsed_payload *payload)
+{
+	return 0;
+}
+
+static void turris_signing_key_describe(const struct key *key, struct seq_file *m)
+{
+	const struct turris_signing_key_subtype *subtype = dereference_key_rcu(key);
+
+	if (!subtype)
+		return;
+
+	seq_printf(m, "%s: %*phN", key->description, subtype->public_key_size,
+		   subtype->get_public_key(key));
+}
+
+static long turris_signing_key_read(const struct key *key, char *buffer, size_t buflen)
+{
+	const struct turris_signing_key_subtype *subtype = dereference_key_rcu(key);
+
+	if (!subtype)
+		return -EIO;
+
+	if (buffer) {
+		if (buflen > subtype->public_key_size)
+			buflen = subtype->public_key_size;
+
+		memcpy(buffer, subtype->get_public_key(key), subtype->public_key_size);
+	}
+
+	return subtype->public_key_size;
+}
+
+static bool turris_signing_key_asym_valid_params(const struct turris_signing_key_subtype *subtype,
+						 const struct kernel_pkey_params *params)
+{
+	if (params->encoding && strcmp(params->encoding, "raw"))
+		return false;
+
+	if (params->hash_algo && strcmp(params->hash_algo, subtype->hash_algo))
+		return false;
+
+	return true;
+}
+
+static int turris_signing_key_asym_query(const struct kernel_pkey_params *params,
+					 struct kernel_pkey_query *info)
+{
+	const struct turris_signing_key_subtype *subtype = dereference_key_rcu(params->key);
+
+	if (!subtype)
+		return -EIO;
+
+	if (!turris_signing_key_asym_valid_params(subtype, params))
+		return -EINVAL;
+
+	info->supported_ops = KEYCTL_SUPPORTS_SIGN;
+	info->key_size = subtype->key_size;
+	info->max_data_size = subtype->data_size;
+	info->max_sig_size = subtype->sig_size;
+	info->max_enc_size = 0;
+	info->max_dec_size = 0;
+
+	return 0;
+}
+
+static int turris_signing_key_asym_eds_op(struct kernel_pkey_params *params,
+				 const void *in, void *out)
+{
+	const struct turris_signing_key_subtype *subtype = dereference_key_rcu(params->key);
+	int err;
+
+	if (!subtype)
+		return -EIO;
+
+	if (!turris_signing_key_asym_valid_params(subtype, params))
+		return -EINVAL;
+
+	if (params->op != kernel_pkey_sign)
+		return -EOPNOTSUPP;
+
+	if (params->in_len != subtype->data_size || params->out_len != subtype->sig_size)
+		return -EINVAL;
+
+	err = subtype->sign(params->key, in, out);
+	if (err)
+		return err;
+
+	return subtype->sig_size;
+}
+
+static struct key_type turris_signing_key_type = {
+	.name		= "turris-signing-key",
+	.instantiate	= turris_signing_key_instantiate,
+	.describe	= turris_signing_key_describe,
+	.read		= turris_signing_key_read,
+	.asym_query	= turris_signing_key_asym_query,
+	.asym_eds_op	= turris_signing_key_asym_eds_op,
+};
+
+static struct key *turris_signing_keyring;
+
+static void turris_signing_key_release(void *key)
+{
+	key_unlink(turris_signing_keyring, key);
+	key_put(key);
+}
+
+int
+devm_turris_signing_key_create(struct device *dev, const struct turris_signing_key_subtype *subtype,
+			       const char *desc)
+{
+	struct key *key;
+	key_ref_t kref;
+
+	kref = key_create(make_key_ref(turris_signing_keyring, true),
+			  turris_signing_key_type.name, desc, NULL, 0,
+			  (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW | KEY_USR_READ |
+			  KEY_USR_SEARCH,
+			  KEY_ALLOC_BUILT_IN | KEY_ALLOC_SET_KEEP | KEY_ALLOC_NOT_IN_QUOTA);
+	if (IS_ERR(kref))
+		return PTR_ERR(kref);
+
+	key = key_ref_to_ptr(kref);
+	key->payload.data[1] = dev;
+	rcu_assign_keypointer(key, subtype);
+
+	return devm_add_action_or_reset(dev, turris_signing_key_release, key);
+}
+EXPORT_SYMBOL_GPL(devm_turris_signing_key_create);
+
+static int turris_signing_key_init(void)
+{
+	int err;
+
+	err = register_key_type(&turris_signing_key_type);
+	if (err)
+		return err;
+
+	turris_signing_keyring = keyring_alloc(".turris-signing-keys",
+					       GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, current_cred(),
+					       (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_VIEW |
+					       KEY_USR_READ | KEY_USR_SEARCH,
+					       KEY_ALLOC_BUILT_IN | KEY_ALLOC_SET_KEEP |
+					       KEY_ALLOC_NOT_IN_QUOTA,
+					       NULL, NULL);
+	if (IS_ERR(turris_signing_keyring)) {
+		pr_err("Cannot allocate Turris keyring\n");
+
+		unregister_key_type(&turris_signing_key_type);
+
+		return PTR_ERR(turris_signing_keyring);
+	}
+
+	return 0;
+}
+module_init(turris_signing_key_init);
+
+static void turris_signing_key_exit(void)
+{
+	key_put(turris_signing_keyring);
+	unregister_key_type(&turris_signing_key_type);
+}
+module_exit(turris_signing_key_exit);
+
+MODULE_AUTHOR("Marek Behun <kabel@kernel.org>");
+MODULE_DESCRIPTION("CZ.NIC's Turris signing key helper");
+MODULE_LICENSE("GPL");