openwrt/target/linux/mvebu/patches-5.4/030-linkstation-poweroff.patch

--- a/drivers/power/reset/Kconfig
+++ b/drivers/power/reset/Kconfig
@@ -99,6 +99,17 @@ config POWER_RESET_HISI
 	help
 	  Reboot support for Hisilicon boards.
 
+config POWER_RESET_LINKSTATION
+	tristate "Buffalo LinkStation power-off driver"
+	depends on ARCH_MVEBU || COMPILE_TEST
+	depends on OF_MDIO && PHYLIB
+	help
+	  This driver supports turning off some Buffalo LinkStations by
+	  setting an output pin at the ethernet PHY to the correct state.
+	  It also makes the device compatible with the WoL function.
+
+	  Say Y here if you have a Buffalo LinkStation LS421D/E.
+
 config POWER_RESET_MSM
 	bool "Qualcomm MSM power-off driver"
 	depends on ARCH_QCOM
--- a/drivers/power/reset/Makefile
+++ b/drivers/power/reset/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_POWER_RESET_GEMINI_POWEROFF
 obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
 obj-$(CONFIG_POWER_RESET_GPIO_RESTART) += gpio-restart.o
 obj-$(CONFIG_POWER_RESET_HISI) += hisi-reboot.o
+obj-${CONFIG_POWER_RESET_LINKSTATION} += linkstation-poweroff.o
 obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o
 obj-$(CONFIG_POWER_RESET_QCOM_PON) += qcom-pon.o
 obj-$(CONFIG_POWER_RESET_OCELOT_RESET) += ocelot-reset.o
--- /dev/null
+++ b/drivers/power/reset/linkstation-poweroff.c
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * LinkStation power off restart driver
+ * Copyright (C) 2020 Daniel González Cabanelas <dgcbueu@gmail.com>
+ */
+
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+#include <linux/of_mdio.h>
+#include <linux/of_platform.h>
+#include <linux/reboot.h>
+#include <linux/phy.h>
+
+/* Defines from the eth phy Marvell driver */
+#define MII_MARVELL_COPPER_PAGE		0
+#define MII_MARVELL_LED_PAGE		3
+#define MII_MARVELL_WOL_PAGE		17
+#define MII_MARVELL_PHY_PAGE		22
+
+#define MII_PHY_LED_CTRL		16
+#define MII_88E1318S_PHY_LED_TCR	18
+#define MII_88E1318S_PHY_WOL_CTRL	16
+#define MII_M1011_IEVENT		19
+
+#define MII_88E1318S_PHY_LED_TCR_INTn_ENABLE		BIT(7)
+#define MII_88E1318S_PHY_LED_TCR_FORCE_INT		BIT(15)
+#define MII_88E1318S_PHY_WOL_CTRL_CLEAR_WOL_STATUS	BIT(12)
+#define LED2_FORCE_ON					(0x8 << 8)
+#define LEDMASK						GENMASK(11,8)
+
+static struct phy_device *phydev;
+
+static void mvphy_reg_intn(u16 data)
+{
+	int rc = 0, saved_page;
+
+	saved_page = phy_select_page(phydev, MII_MARVELL_LED_PAGE);
+	if (saved_page < 0)
+		goto err;
+
+	/* Force manual LED2 control to let INTn work */
+	__phy_modify(phydev, MII_PHY_LED_CTRL, LEDMASK, LED2_FORCE_ON);
+
+	/* Set the LED[2]/INTn pin to the required state */
+	__phy_modify(phydev, MII_88E1318S_PHY_LED_TCR,
+		     MII_88E1318S_PHY_LED_TCR_FORCE_INT,
+		     MII_88E1318S_PHY_LED_TCR_INTn_ENABLE | data);
+
+	if (!data) {
+		/* Clear interrupts to ensure INTn won't be holded in high state */
+		__phy_write(phydev, MII_MARVELL_PHY_PAGE, MII_MARVELL_COPPER_PAGE);
+		__phy_read(phydev, MII_M1011_IEVENT);
+
+		/* If WOL was enabled and a magic packet was received before powering
+		 * off, we won't be able to wake up by sending another magic packet. 
+		 * Clear WOL status.
+		 */
+		__phy_write(phydev, MII_MARVELL_PHY_PAGE, MII_MARVELL_WOL_PAGE);
+		__phy_set_bits(phydev, MII_88E1318S_PHY_WOL_CTRL,
+			       MII_88E1318S_PHY_WOL_CTRL_CLEAR_WOL_STATUS);
+	}
+err:
+	rc = phy_restore_page(phydev, saved_page, rc);
+	if (rc < 0)
+		dev_err(&phydev->mdio.dev, "Write register failed, %d\n", rc);
+
+	if (!data) {
+		/* Slow down the PHY to save energy */
+		rc= phy_speed_down(phydev, false);
+		if (rc < 0)
+			dev_err(&phydev->mdio.dev, "PHY speed down failed, %d\n", rc);
+	}
+}
+
+static int linkstation_reboot_notifier(struct notifier_block *nb,
+				       unsigned long action, void *unused)
+{
+	if (action == SYS_RESTART)
+		mvphy_reg_intn(MII_88E1318S_PHY_LED_TCR_FORCE_INT);
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block linkstation_reboot_nb = {
+	.notifier_call = linkstation_reboot_notifier,
+};
+
+static void linkstation_poweroff(void)
+{
+	unregister_reboot_notifier(&linkstation_reboot_nb);
+	mvphy_reg_intn(0);
+
+	kernel_restart("Power off");
+}
+
+static const struct of_device_id ls_poweroff_of_match[] = {
+	{ .compatible = "buffalo,ls421d" },
+	{ .compatible = "buffalo,ls421de" },
+	{ },
+};
+
+static int __init linkstation_poweroff_init(void)
+{
+	struct mii_bus *bus;
+	struct device_node *dn;
+
+	dn = of_find_matching_node(NULL, ls_poweroff_of_match);
+	if (!dn)
+		return -ENODEV;
+	of_node_put(dn);
+
+	dn = of_find_node_by_name(NULL, "mdio");
+	if (!dn)
+		return -ENODEV;
+
+	bus = of_mdio_find_bus(dn);
+	of_node_put(dn);
+	if (!bus)
+		return -EPROBE_DEFER;
+
+	phydev = phy_find_first(bus);
+	if (!phydev)
+		return -EPROBE_DEFER;
+
+	register_reboot_notifier(&linkstation_reboot_nb);
+	pm_power_off = linkstation_poweroff;
+
+	pr_info("LinkStation power off driver registered\n");
+	return 0;
+}
+
+static void __exit linkstation_poweroff_exit(void)
+{
+	pm_power_off = NULL;
+	unregister_reboot_notifier(&linkstation_reboot_nb);
+}
+
+module_init(linkstation_poweroff_init);
+module_exit(linkstation_poweroff_exit);
+
+MODULE_AUTHOR("Daniel González Cabanelas <dgcbueu@gmail.com>");
+MODULE_DESCRIPTION("LinkStation power off driver");
+MODULE_LICENSE("GPL v2");