From f69e0a731ab471f3a57c48258ad2d9990820c173 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marek=20Beh=C3=BAn?= Date: Mon, 1 Jul 2024 13:30:06 +0200 Subject: [PATCH 04/11] platform: cznic: turris-omnia-mcu: Add support for poweroff and wakeup MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add support for true board poweroff (MCU can disable all unnecessary voltage regulators) and wakeup at a specified time, implemented via a RTC driver so that the rtcwake utility can be used to configure it. Signed-off-by: Marek Behún Reviewed-by: Andy Shevchenko Acked-by: Alexandre Belloni Acked-by: Bartosz Golaszewski Link: https://lore.kernel.org/r/20240701113010.16447-5-kabel@kernel.org Signed-off-by: Arnd Bergmann --- .../sysfs-bus-i2c-devices-turris-omnia-mcu | 16 ++ drivers/platform/cznic/Kconfig | 4 + drivers/platform/cznic/Makefile | 1 + .../platform/cznic/turris-omnia-mcu-base.c | 5 + .../cznic/turris-omnia-mcu-sys-off-wakeup.c | 260 ++++++++++++++++++ drivers/platform/cznic/turris-omnia-mcu.h | 20 ++ 6 files changed, 306 insertions(+) create mode 100644 drivers/platform/cznic/turris-omnia-mcu-sys-off-wakeup.c --- a/Documentation/ABI/testing/sysfs-bus-i2c-devices-turris-omnia-mcu +++ b/Documentation/ABI/testing/sysfs-bus-i2c-devices-turris-omnia-mcu @@ -38,6 +38,22 @@ Description: (RW) The front button on th Format: %s. +What: /sys/bus/i2c/devices//front_button_poweron +Date: September 2024 +KernelVersion: 6.11 +Contact: Marek Behún +Description: (RW) Newer versions of the microcontroller firmware of the + Turris Omnia router support powering off the router into true + low power mode. The router can be powered on by pressing the + front button. + + This file configures whether front button power on is enabled. + + This file is present only if the power off feature is supported + by the firmware. + + Format: %i. + What: /sys/bus/i2c/devices//fw_features Date: September 2024 KernelVersion: 6.11 --- a/drivers/platform/cznic/Kconfig +++ b/drivers/platform/cznic/Kconfig @@ -18,10 +18,14 @@ config TURRIS_OMNIA_MCU depends on I2C select GPIOLIB select GPIOLIB_IRQCHIP + select RTC_CLASS help Say Y here to add support for the features implemented by the microcontroller on the CZ.NIC's Turris Omnia SOHO router. The features include: + - board poweroff into true low power mode (with voltage regulators + disabled) and the ability to configure wake up from this mode (via + rtcwake) - GPIO pins - to get front button press events (the front button can be configured either to generate press events to the CPU or to change --- a/drivers/platform/cznic/Makefile +++ b/drivers/platform/cznic/Makefile @@ -3,3 +3,4 @@ obj-$(CONFIG_TURRIS_OMNIA_MCU) += turris-omnia-mcu.o turris-omnia-mcu-y := turris-omnia-mcu-base.o turris-omnia-mcu-y += turris-omnia-mcu-gpio.o +turris-omnia-mcu-y += turris-omnia-mcu-sys-off-wakeup.o --- a/drivers/platform/cznic/turris-omnia-mcu-base.c +++ b/drivers/platform/cznic/turris-omnia-mcu-base.c @@ -197,6 +197,7 @@ static const struct attribute_group omni static const struct attribute_group *omnia_mcu_groups[] = { &omnia_mcu_base_group, &omnia_mcu_gpio_group, + &omnia_mcu_poweroff_group, NULL }; @@ -371,6 +372,10 @@ static int omnia_mcu_probe(struct i2c_cl "Cannot read board info\n"); } + err = omnia_mcu_register_sys_off_and_wakeup(mcu); + if (err) + return err; + return omnia_mcu_register_gpiochip(mcu); } --- /dev/null +++ b/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 + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#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; +} --- a/drivers/platform/cznic/turris-omnia-mcu.h +++ b/drivers/platform/cznic/turris-omnia-mcu.h @@ -15,8 +15,10 @@ #include #include #include +#include struct i2c_client; +struct rtc_device; struct omnia_mcu { struct i2c_client *client; @@ -36,6 +38,11 @@ struct omnia_mcu { struct delayed_work button_release_emul_work; unsigned long last_status; bool button_pressed_emul; + + /* RTC device for configuring wake-up */ + struct rtc_device *rtcdev; + u32 rtc_alarm; + bool front_button_poweron; }; int omnia_cmd_write_read(const struct i2c_client *client, @@ -48,6 +55,17 @@ static inline int omnia_cmd_write(const return omnia_cmd_write_read(client, cmd, len, NULL, 0); } +static inline int omnia_cmd_write_u32(const struct i2c_client *client, u8 cmd, + u32 val) +{ + u8 buf[5]; + + buf[0] = cmd; + put_unaligned_le32(val, &buf[1]); + + return omnia_cmd_write(client, buf, sizeof(buf)); +} + static inline int omnia_cmd_read(const struct i2c_client *client, u8 cmd, void *reply, unsigned int len) { @@ -136,7 +154,9 @@ static inline int omnia_cmd_read_u8(cons } extern const struct attribute_group omnia_mcu_gpio_group; +extern const struct attribute_group omnia_mcu_poweroff_group; int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu); +int omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu *mcu); #endif /* __TURRIS_OMNIA_MCU_H */