gpio: turris_omnia_mcu: Add support for system power off via sysreset
Add support for system power off via UCLASS_SYSRESET. Newer versions of
Turris Omnia MCU firmware can power off the board (MCU will disable
almost all voltage regulators and go into low power mode).
Move the MCU driver into drivers/misc and register it under UCLASS_MISC.
The sysreset and gpio device are bound as child devices of the MCU device.
Signed-off-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/drivers/misc/turris_omnia_mcu.c b/drivers/misc/turris_omnia_mcu.c
new file mode 100644
index 0000000..77a0424
--- /dev/null
+++ b/drivers/misc/turris_omnia_mcu.c
@@ -0,0 +1,354 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2022 Pali Rohár <pali@kernel.org>
+ * Copyright (C) 2024 Marek Behún <kabel@kernel.org>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <dm/lists.h>
+#include <i2c.h>
+#include <sysreset.h>
+#include <turris-omnia-mcu-interface.h>
+#include <asm/byteorder.h>
+#include <asm/gpio.h>
+#include <linux/log2.h>
+
+struct turris_omnia_mcu_info {
+ u32 features;
+};
+
+static int omnia_gpio_get_function(struct udevice *dev, uint offset)
+{
+ struct turris_omnia_mcu_info *info = dev_get_priv(dev->parent);
+
+ switch (offset) {
+ /* bank 0 */
+ case 0 ... 15:
+ switch (offset) {
+ case ilog2(STS_USB30_PWRON):
+ case ilog2(STS_USB31_PWRON):
+ case ilog2(STS_ENABLE_4V5):
+ case ilog2(STS_BUTTON_MODE):
+ return GPIOF_OUTPUT;
+ default:
+ return GPIOF_INPUT;
+ }
+
+ /* bank 1 - supported only when FEAT_EXT_CMDS is set */
+ case (16 + 0) ... (16 + 31):
+ if (!(info->features & FEAT_EXT_CMDS))
+ return -EINVAL;
+ return GPIOF_INPUT;
+
+ /* bank 2 - supported only when FEAT_EXT_CMDS and FEAT_PERIPH_MCU is set */
+ case (16 + 32 + 0) ... (16 + 32 + 15):
+ if (!(info->features & FEAT_EXT_CMDS))
+ return -EINVAL;
+ if (!(info->features & FEAT_PERIPH_MCU))
+ return -EINVAL;
+ return GPIOF_OUTPUT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int omnia_gpio_get_value(struct udevice *dev, uint offset)
+{
+ struct turris_omnia_mcu_info *info = dev_get_priv(dev->parent);
+ u32 val32;
+ u16 val16;
+ int ret;
+
+ switch (offset) {
+ /* bank 0 */
+ case 0 ... 15:
+ ret = dm_i2c_read(dev->parent, CMD_GET_STATUS_WORD,
+ (void *)&val16, sizeof(val16));
+ if (ret)
+ return ret;
+
+ return !!(le16_to_cpu(val16) & BIT(offset));
+
+ /* bank 1 - supported only when FEAT_EXT_CMDS is set */
+ case (16 + 0) ... (16 + 31):
+ if (!(info->features & FEAT_EXT_CMDS))
+ return -EINVAL;
+
+ ret = dm_i2c_read(dev->parent, CMD_GET_EXT_STATUS_DWORD,
+ (void *)&val32, sizeof(val32));
+ if (ret)
+ return ret;
+
+ return !!(le32_to_cpu(val32) & BIT(offset - 16));
+
+ /* bank 2 - supported only when FEAT_EXT_CMDS and FEAT_PERIPH_MCU is set */
+ case (16 + 32 + 0) ... (16 + 32 + 15):
+ if (!(info->features & FEAT_EXT_CMDS))
+ return -EINVAL;
+ if (!(info->features & FEAT_PERIPH_MCU))
+ return -EINVAL;
+
+ ret = dm_i2c_read(dev->parent, CMD_GET_EXT_CONTROL_STATUS,
+ (void *)&val16, sizeof(val16));
+ if (ret)
+ return ret;
+
+ return !!(le16_to_cpu(val16) & BIT(offset - 16 - 32));
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int omnia_gpio_set_value(struct udevice *dev, uint offset, int value)
+{
+ struct turris_omnia_mcu_info *info = dev_get_priv(dev->parent);
+ u16 valmask16[2];
+ u8 valmask8[2];
+
+ switch (offset) {
+ /* bank 0 */
+ case 0 ... 15:
+ switch (offset) {
+ case ilog2(STS_USB30_PWRON):
+ valmask8[1] = CTL_USB30_PWRON;
+ break;
+ case ilog2(STS_USB31_PWRON):
+ valmask8[1] = CTL_USB31_PWRON;
+ break;
+ case ilog2(STS_ENABLE_4V5):
+ valmask8[1] = CTL_ENABLE_4V5;
+ break;
+ case ilog2(STS_BUTTON_MODE):
+ valmask8[1] = CTL_BUTTON_MODE;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ valmask8[0] = value ? valmask8[1] : 0;
+
+ return dm_i2c_write(dev->parent, CMD_GENERAL_CONTROL, valmask8,
+ sizeof(valmask8));
+
+ /* bank 2 - supported only when FEAT_EXT_CMDS and FEAT_PERIPH_MCU is set */
+ case (16 + 32 + 0) ... (16 + 32 + 15):
+ if (!(info->features & FEAT_EXT_CMDS))
+ return -EINVAL;
+ if (!(info->features & FEAT_PERIPH_MCU))
+ return -EINVAL;
+
+ valmask16[1] = cpu_to_le16(BIT(offset - 16 - 32));
+ valmask16[0] = value ? valmask16[1] : 0;
+
+ return dm_i2c_write(dev->parent, CMD_EXT_CONTROL,
+ (void *)valmask16, sizeof(valmask16));
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int omnia_gpio_direction_input(struct udevice *dev, uint offset)
+{
+ int ret;
+
+ ret = omnia_gpio_get_function(dev, offset);
+ if (ret < 0)
+ return ret;
+ else if (ret != GPIOF_INPUT)
+ return -EOPNOTSUPP;
+
+ return 0;
+}
+
+static int omnia_gpio_direction_output(struct udevice *dev, uint offset, int value)
+{
+ int ret;
+
+ ret = omnia_gpio_get_function(dev, offset);
+ if (ret < 0)
+ return ret;
+ else if (ret != GPIOF_OUTPUT)
+ return -EOPNOTSUPP;
+
+ return omnia_gpio_set_value(dev, offset, value);
+}
+
+static int omnia_gpio_xlate(struct udevice *dev, struct gpio_desc *desc,
+ struct ofnode_phandle_args *args)
+{
+ uint bank, gpio, flags, offset;
+ int ret;
+
+ if (args->args_count != 3)
+ return -EINVAL;
+
+ bank = args->args[0];
+ gpio = args->args[1];
+ flags = args->args[2];
+
+ switch (bank) {
+ case 0:
+ if (gpio >= 16)
+ return -EINVAL;
+ offset = gpio;
+ break;
+ case 1:
+ if (gpio >= 32)
+ return -EINVAL;
+ offset = 16 + gpio;
+ break;
+ case 2:
+ if (gpio >= 16)
+ return -EINVAL;
+ offset = 16 + 32 + gpio;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ ret = omnia_gpio_get_function(dev, offset);
+ if (ret < 0)
+ return ret;
+
+ desc->offset = offset;
+ desc->flags = gpio_flags_xlate(flags);
+
+ return 0;
+}
+
+static const struct dm_gpio_ops omnia_gpio_ops = {
+ .direction_input = omnia_gpio_direction_input,
+ .direction_output = omnia_gpio_direction_output,
+ .get_value = omnia_gpio_get_value,
+ .set_value = omnia_gpio_set_value,
+ .get_function = omnia_gpio_get_function,
+ .xlate = omnia_gpio_xlate,
+};
+
+static int omnia_gpio_probe(struct udevice *dev)
+{
+ struct turris_omnia_mcu_info *info = dev_get_priv(dev->parent);
+ struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+ uc_priv->bank_name = "mcu_";
+
+ if ((info->features & FEAT_EXT_CMDS) && (info->features & FEAT_PERIPH_MCU))
+ uc_priv->gpio_count = 16 + 32 + 16;
+ else if (info->features & FEAT_EXT_CMDS)
+ uc_priv->gpio_count = 16 + 32;
+ else
+ uc_priv->gpio_count = 16;
+
+ return 0;
+}
+
+U_BOOT_DRIVER(turris_omnia_mcu_gpio) = {
+ .name = "turris-omnia-mcu-gpio",
+ .id = UCLASS_GPIO,
+ .ops = &omnia_gpio_ops,
+ .probe = omnia_gpio_probe,
+};
+
+static int omnia_sysreset_request(struct udevice *dev, enum sysreset_t type)
+{
+ struct {
+ u16 magic;
+ u16 arg;
+ u32 csum;
+ } __packed args;
+
+ if (type != SYSRESET_POWER_OFF)
+ return -EPROTONOSUPPORT;
+
+ args.magic = CMD_POWER_OFF_MAGIC;
+ args.arg = CMD_POWER_OFF_POWERON_BUTTON;
+ args.csum = 0xba3b7212;
+
+ return dm_i2c_write(dev->parent, CMD_POWER_OFF, (void *)&args,
+ sizeof(args));
+}
+
+static const struct sysreset_ops omnia_sysreset_ops = {
+ .request = omnia_sysreset_request,
+};
+
+U_BOOT_DRIVER(turris_omnia_mcu_sysreset) = {
+ .name = "turris-omnia-mcu-sysreset",
+ .id = UCLASS_SYSRESET,
+ .ops = &omnia_sysreset_ops,
+};
+
+static int turris_omnia_mcu_bind(struct udevice *dev)
+{
+ /* bind MCU GPIOs as a child device */
+ return device_bind_driver_to_node(dev, "turris-omnia-mcu-gpio",
+ "turris-omnia-mcu-gpio",
+ dev_ofnode(dev), NULL);
+}
+
+static int turris_omnia_mcu_probe(struct udevice *dev)
+{
+ struct turris_omnia_mcu_info *info = dev_get_priv(dev);
+ u32 dword;
+ u16 word;
+ int ret;
+
+ ret = dm_i2c_read(dev, CMD_GET_STATUS_WORD, (void *)&word, sizeof(word));
+ if (ret < 0) {
+ printf("Error: turris_omnia_mcu CMD_GET_STATUS_WORD failed: %d\n",
+ ret);
+ return ret;
+ }
+
+ if (le16_to_cpu(word) & STS_FEATURES_SUPPORTED) {
+ /* try read 32-bit features */
+ ret = dm_i2c_read(dev, CMD_GET_FEATURES, (void *)&dword,
+ sizeof(dword));
+ if (ret < 0) {
+ /* try read 16-bit features */
+ ret = dm_i2c_read(dev, CMD_GET_FEATURES, (void *)&word,
+ sizeof(word));
+ if (ret < 0) {
+ printf("Error: turris_omnia_mcu CMD_GET_FEATURES failed: %d\n",
+ ret);
+ return ret;
+ }
+
+ info->features = le16_to_cpu(word);
+ } else {
+ info->features = le32_to_cpu(dword);
+ if (info->features & FEAT_FROM_BIT_16_INVALID)
+ info->features &= GENMASK(15, 0);
+ }
+ }
+
+ /* bind sysreset if poweroff is supported */
+ if (info->features & FEAT_POWEROFF_WAKEUP) {
+ ret = device_bind_driver_to_node(dev,
+ "turris-omnia-mcu-sysreset",
+ "turris-omnia-mcu-sysreset",
+ dev_ofnode(dev), NULL);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct udevice_id turris_omnia_mcu_ids[] = {
+ { .compatible = "cznic,turris-omnia-mcu" },
+ { }
+};
+
+U_BOOT_DRIVER(turris_omnia_mcu) = {
+ .name = "turris-omnia-mcu",
+ .id = UCLASS_MISC,
+ .bind = turris_omnia_mcu_bind,
+ .probe = turris_omnia_mcu_probe,
+ .priv_auto = sizeof(struct turris_omnia_mcu_info),
+ .of_match = turris_omnia_mcu_ids,
+};