Re: [PATCH v2] power: reset: add Odroid Go Ultra poweroff driver
From: Neil Armstrong
Date: Mon Jan 30 2023 - 03:31:36 EST
On 30/01/2023 00:47, Sebastian Reichel wrote:
Hi,
On Thu, Jan 26, 2023 at 06:11:21PM +0100, Neil Armstrong wrote:
The Hardkernel Odroid Go Ultra poweroff scheme requires requesting a poweroff
to its two PMICs in order, this represents the poweroff scheme needed to complete
a clean poweroff of the system.
This implement this scheme by implementing a self registering driver to permit
using probe defer until both pmics are finally probed.
Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
---
Previous submission was at [1], but I converted it to an independent
platform device with device auto registration to permit waiting for
both the PMICs drivers to probe.
[1] https://lore.kernel.org/all/20221031-b4-odroid-go-ultra-initial-v1-2-42e3dbea86d5@xxxxxxxxxx/
---
Changes in v2:
- Switched to devm_register_sys_off_handler()
- Link to v1: https://lore.kernel.org/r/20221031-b4-odroid-go-ultra-initial-v1-2-42e3dbea86d5@xxxxxxxxxx
---
drivers/power/reset/Kconfig | 7 ++
drivers/power/reset/Makefile | 1 +
drivers/power/reset/odroid-go-ultra-poweroff.c | 151 +++++++++++++++++++++++++
3 files changed, 159 insertions(+)
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig
index a8c46ba5878f..26860c2e05a9 100644
--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -141,6 +141,13 @@ config POWER_RESET_OCELOT_RESET
help
This driver supports restart for Microsemi Ocelot SoC and similar.
+config POWER_RESET_ODROID_GO_ULTRA_POWEROFF
+ bool "Odroid Go Ultra power-off driver"
+ depends on ARCH_MESON || COMPILE_TEST
+ depends on MFD_RK808
You are not accessing any symbols from the MFD driver, so you can
append "|| COMPILE_TEST".
It will be fun to coordinate the merging, because of my series
renaming it to MFD_RK8XX :/
https://lore.kernel.org/all/20230127181244.160887-1-sebastian.reichel@xxxxxxxxxxxxx/
If I do not depend anymore on `struct rk808`, so I don't depend anymore on it,
but if it doesn't probe I won't get the regmap from the i2c device.
So it will be a runtime dependency instead, so it's ok to drop.
But I'll need to add a depend to guard of_find_i2c_device_by_node()
+ help
+ This driver supports Power off for Odroid Go Ultra device.
+
config POWER_RESET_OXNAS
bool "OXNAS SoC restart driver"
depends on ARCH_OXNAS
diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile
index 0a39424fc558..d763e6735ee3 100644
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_POWER_RESET_MT6323) += mt6323-poweroff.o
obj-$(CONFIG_POWER_RESET_OXNAS) += oxnas-restart.o
obj-$(CONFIG_POWER_RESET_QCOM_PON) += qcom-pon.o
obj-$(CONFIG_POWER_RESET_OCELOT_RESET) += ocelot-reset.o
+obj-$(CONFIG_POWER_RESET_ODROID_GO_ULTRA_POWEROFF) += odroid-go-ultra-poweroff.o
obj-$(CONFIG_POWER_RESET_PIIX4_POWEROFF) += piix4-poweroff.o
obj-$(CONFIG_POWER_RESET_LTC2952) += ltc2952-poweroff.o
obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
diff --git a/drivers/power/reset/odroid-go-ultra-poweroff.c b/drivers/power/reset/odroid-go-ultra-poweroff.c
new file mode 100644
index 000000000000..51f54e65c927
--- /dev/null
+++ b/drivers/power/reset/odroid-go-ultra-poweroff.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2023 Neil Armstrong <neil.armstrong@xxxxxxxxxx>
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/of_platform.h>
+#include <linux/mfd/rk808.h>
+#include <linux/regmap.h>
+#include <linux/module.h>
+#include <linux/reboot.h>
+#include <linux/i2c.h>
+
+/*
+ * The Odroid Go Ultra has 2 PMICs:
+ * - RK818 (manages the battery and USB-C power supply)
+ * - RK817
+ * Both PMICs feeds power to the S922X SoC, so they must be powered-off in sequence.
+ * Vendor does power-off the RK817 first, then the RK818 so here we follow this sequence.
+ */
+
+struct odroid_go_ultra_poweroff_data {
+ struct device *dev;
+ struct rk808 *rk817;
+ struct rk808 *rk818;
+};
+
+static int odroid_go_ultra_poweroff_prepare(struct sys_off_data *data)
+{
+ struct odroid_go_ultra_poweroff_data *poweroff_data = data->cb_data;
+ int ret;
+
+ dev_info(poweroff_data->dev, "Setting PMICs for power off");
+
+ /* RK817 */
+ ret = regmap_update_bits(poweroff_data->rk817->regmap, RK817_SYS_CFG(3), DEV_OFF, DEV_OFF);
+ if (ret) {
+ dev_err(poweroff_data->dev, "failed to poweroff rk817\n");
+ return notifier_from_errno(ret);
+ }
+
+ /* RK818 */
+ ret = regmap_update_bits(poweroff_data->rk818->regmap, RK818_DEVCTRL_REG, DEV_OFF, DEV_OFF);
+ if (ret) {
+ dev_err(poweroff_data->dev, "failed to poweroff rk818\n");
+ return notifier_from_errno(ret);
+ }
+
+ return NOTIFY_OK;
+}
+
+static int odroid_go_ultra_poweroff_get_pmic_drvdata(const char *compatible, struct rk808 **pmic)
+{
+ struct device_node *pmic_node;
+ struct i2c_client *pmic_client;
+
+ pmic_node = of_find_compatible_node(NULL, NULL, compatible);
+ if (!pmic_node)
+ return -ENODEV;
+
+ pmic_client = of_find_i2c_device_by_node(pmic_node);
+ of_node_put(pmic_node);
+ if (!pmic_client)
+ return -EPROBE_DEFER;
+
+ *pmic = i2c_get_clientdata(pmic_client);
You are only using the regmap, so you can skip the rk808 struct step
and directly get and store the regmap: >
*pmic = dev_get_regmap(&pmic_client->dev, NULL);
Indeed ti makes things much simpler.
+ put_device(&pmic_client->dev);
Technically this allows releasing the PMIC device with the poweroff
driver still probed. I guess it's mostly a theoretical thing in this
case, but people tend to cargo copy. I suggest to store the struct
device handle in odroid_go_ultra_poweroff_data and then use
dev_get_regmap() in the poweroff handler. Finally add a put_device()
via devm_add_action_or_reset().
Indeed, this makes it much cleaner.
+ if (!*pmic)
+ return -EPROBE_DEFER;
+
+ return 0;
+}
+
+static int odroid_go_ultra_poweroff_probe(struct platform_device *pdev)
+{
+ struct odroid_go_ultra_poweroff_data *poweroff_data;
+ int ret;
+
+ poweroff_data = devm_kzalloc(&pdev->dev, sizeof(*poweroff_data), GFP_KERNEL);
+ if (!poweroff_data)
+ return -ENOMEM;
+
+ dev_set_drvdata(&pdev->dev, poweroff_data);
+
+ /* RK818 */
+ ret = odroid_go_ultra_poweroff_get_pmic_drvdata("rockchip,rk818",
+ &poweroff_data->rk818);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret, "failed to get rk818 mfd data\n");
+
+ /* RK817 */
+ ret = odroid_go_ultra_poweroff_get_pmic_drvdata("rockchip,rk817",
+ &poweroff_data->rk817);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret, "failed to get rk817 mfd data\n");
+
+ /* Register as SYS_OFF_MODE_POWER_OFF_PREPARE because regmap_update_bits may sleep */
+ ret = devm_register_sys_off_handler(&pdev->dev,
+ SYS_OFF_MODE_POWER_OFF_PREPARE,
+ SYS_OFF_PRIO_DEFAULT,
+ odroid_go_ultra_poweroff_prepare,
+ poweroff_data);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret, "failed to register sys-off handler\n");
+
+ dev_info(&pdev->dev, "Registered Power-Off handler\n");
+
+ return 0;
+}
+
+static struct platform_device *pdev;
+
+static struct platform_driver odroid_go_ultra_poweroff_driver = {
+ .driver = {
+ .name = "odroid-go-ultra-poweroff",
+ },
+ .probe = odroid_go_ultra_poweroff_probe,
+};
+
+static int __init odroid_go_ultra_poweroff_init(void)
+{
+ int ret;
+
+ /* Only create when running on the Odroid Go Ultra device */
+ if (!of_device_is_compatible(of_root, "hardkernel,odroid-go-ultra"))
+ return -ENODEV;
+
+ ret = platform_driver_register(&odroid_go_ultra_poweroff_driver);
+ if (ret)
+ return ret;
+
+ pdev = platform_device_register_resndata(NULL, "odroid-go-ultra-poweroff", -1,
+ NULL, 0, NULL, 0);
+
+ return PTR_ERR_OR_ZERO(pdev);
This is missing platform_driver_unregister() in the error path.
Ack
+}
+
+static void __exit odroid_go_ultra_poweroff_exit(void)
+{
if (!of_device_is_compatible(of_root, "hardkernel,odroid-go-ultra"))
return;
Ack
+ platform_device_unregister(pdev);
+ platform_driver_unregister(&odroid_go_ultra_poweroff_driver);
+}
+
+module_init(odroid_go_ultra_poweroff_init);
+module_exit(odroid_go_ultra_poweroff_exit);
+
+MODULE_AUTHOR("Neil Armstrong <neil.armstrong@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Odroid Go Ultra poweroff driver");
+MODULE_LICENSE("GPL");
Thanks,
-- Sebastian
Thanks,
Neil