xref: /linux/drivers/power/reset/linkstation-poweroff.c (revision 762f99f4f3cb41a775b5157dd761217beba65873)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * LinkStation power off restart driver
4  * Copyright (C) 2020 Daniel González Cabanelas <dgcbueu@gmail.com>
5  */
6 
7 #include <linux/module.h>
8 #include <linux/notifier.h>
9 #include <linux/of.h>
10 #include <linux/of_mdio.h>
11 #include <linux/of_platform.h>
12 #include <linux/reboot.h>
13 #include <linux/phy.h>
14 
15 /* Defines from the eth phy Marvell driver */
16 #define MII_MARVELL_COPPER_PAGE		0
17 #define MII_MARVELL_LED_PAGE		3
18 #define MII_MARVELL_WOL_PAGE		17
19 #define MII_MARVELL_PHY_PAGE		22
20 
21 #define MII_PHY_LED_CTRL		16
22 #define MII_PHY_LED_POL_CTRL		17
23 #define MII_88E1318S_PHY_LED_TCR	18
24 #define MII_88E1318S_PHY_WOL_CTRL	16
25 #define MII_M1011_IEVENT		19
26 
27 #define MII_88E1318S_PHY_LED_TCR_INTn_ENABLE		BIT(7)
28 #define MII_88E1318S_PHY_LED_TCR_FORCE_INT		BIT(15)
29 #define MII_88E1318S_PHY_WOL_CTRL_CLEAR_WOL_STATUS	BIT(12)
30 #define LED2_FORCE_ON					(0x8 << 8)
31 #define LEDMASK						GENMASK(11,8)
32 
33 #define MII_88E1318S_PHY_LED_POL_LED2		BIT(4)
34 
35 struct power_off_cfg {
36 	char *mdio_node_name;
37 	void (*phy_set_reg)(bool restart);
38 };
39 
40 static struct phy_device *phydev;
41 static const struct power_off_cfg *cfg;
42 
linkstation_mvphy_reg_intn(bool restart)43 static void linkstation_mvphy_reg_intn(bool restart)
44 {
45 	int rc = 0, saved_page;
46 	u16 data = 0;
47 
48 	if (restart)
49 		data = MII_88E1318S_PHY_LED_TCR_FORCE_INT;
50 
51 	saved_page = phy_select_page(phydev, MII_MARVELL_LED_PAGE);
52 	if (saved_page < 0)
53 		goto err;
54 
55 	/* Force manual LED2 control to let INTn work */
56 	__phy_modify(phydev, MII_PHY_LED_CTRL, LEDMASK, LED2_FORCE_ON);
57 
58 	/* Set the LED[2]/INTn pin to the required state */
59 	__phy_modify(phydev, MII_88E1318S_PHY_LED_TCR,
60 		     MII_88E1318S_PHY_LED_TCR_FORCE_INT,
61 		     MII_88E1318S_PHY_LED_TCR_INTn_ENABLE | data);
62 
63 	if (!data) {
64 		/* Clear interrupts to ensure INTn won't be holded in high state */
65 		__phy_write(phydev, MII_MARVELL_PHY_PAGE, MII_MARVELL_COPPER_PAGE);
66 		__phy_read(phydev, MII_M1011_IEVENT);
67 
68 		/* If WOL was enabled and a magic packet was received before powering
69 		 * off, we won't be able to wake up by sending another magic packet.
70 		 * Clear WOL status.
71 		 */
72 		__phy_write(phydev, MII_MARVELL_PHY_PAGE, MII_MARVELL_WOL_PAGE);
73 		__phy_set_bits(phydev, MII_88E1318S_PHY_WOL_CTRL,
74 			       MII_88E1318S_PHY_WOL_CTRL_CLEAR_WOL_STATUS);
75 	}
76 err:
77 	rc = phy_restore_page(phydev, saved_page, rc);
78 	if (rc < 0)
79 		dev_err(&phydev->mdio.dev, "Write register failed, %d\n", rc);
80 }
81 
readynas_mvphy_set_reg(bool restart)82 static void readynas_mvphy_set_reg(bool restart)
83 {
84 	int rc = 0, saved_page;
85 	u16 data = 0;
86 
87 	if (restart)
88 		data = MII_88E1318S_PHY_LED_POL_LED2;
89 
90 	saved_page = phy_select_page(phydev, MII_MARVELL_LED_PAGE);
91 	if (saved_page < 0)
92 		goto err;
93 
94 	/* Set the LED[2].0 Polarity bit to the required state */
95 	__phy_modify(phydev, MII_PHY_LED_POL_CTRL,
96 		     MII_88E1318S_PHY_LED_POL_LED2, data);
97 
98 	if (!data) {
99 		/* If WOL was enabled and a magic packet was received before powering
100 		 * off, we won't be able to wake up by sending another magic packet.
101 		 * Clear WOL status.
102 		 */
103 		__phy_write(phydev, MII_MARVELL_PHY_PAGE, MII_MARVELL_WOL_PAGE);
104 		__phy_set_bits(phydev, MII_88E1318S_PHY_WOL_CTRL,
105 			       MII_88E1318S_PHY_WOL_CTRL_CLEAR_WOL_STATUS);
106 	}
107 err:
108 	rc = phy_restore_page(phydev, saved_page, rc);
109 	if (rc < 0)
110 		dev_err(&phydev->mdio.dev, "Write register failed, %d\n", rc);
111 }
112 
113 static const struct power_off_cfg linkstation_power_off_cfg = {
114 	.mdio_node_name = "mdio",
115 	.phy_set_reg = linkstation_mvphy_reg_intn,
116 };
117 
118 static const struct power_off_cfg readynas_power_off_cfg = {
119 	.mdio_node_name = "mdio-bus",
120 	.phy_set_reg = readynas_mvphy_set_reg,
121 };
122 
linkstation_reboot_notifier(struct notifier_block * nb,unsigned long action,void * unused)123 static int linkstation_reboot_notifier(struct notifier_block *nb,
124 				       unsigned long action, void *unused)
125 {
126 	if (action == SYS_RESTART)
127 		cfg->phy_set_reg(true);
128 
129 	return NOTIFY_DONE;
130 }
131 
132 static struct notifier_block linkstation_reboot_nb = {
133 	.notifier_call = linkstation_reboot_notifier,
134 };
135 
linkstation_poweroff(void)136 static void linkstation_poweroff(void)
137 {
138 	unregister_reboot_notifier(&linkstation_reboot_nb);
139 	cfg->phy_set_reg(false);
140 
141 	kernel_restart("Power off");
142 }
143 
144 static const struct of_device_id ls_poweroff_of_match[] = {
145 	{ .compatible = "buffalo,ls421d",
146 	  .data = &linkstation_power_off_cfg,
147 	},
148 	{ .compatible = "buffalo,ls421de",
149 	  .data = &linkstation_power_off_cfg,
150 	},
151 	{ .compatible = "netgear,readynas-duo-v2",
152 	  .data = &readynas_power_off_cfg,
153 	},
154 	{ },
155 };
156 
linkstation_poweroff_init(void)157 static int __init linkstation_poweroff_init(void)
158 {
159 	struct mii_bus *bus;
160 	struct device_node *dn;
161 	const struct of_device_id *match;
162 
163 	dn = of_find_matching_node(NULL, ls_poweroff_of_match);
164 	if (!dn)
165 		return -ENODEV;
166 	of_node_put(dn);
167 
168 	match = of_match_node(ls_poweroff_of_match, dn);
169 	cfg = match->data;
170 
171 	dn = of_find_node_by_name(NULL, cfg->mdio_node_name);
172 	if (!dn)
173 		return -ENODEV;
174 
175 	bus = of_mdio_find_bus(dn);
176 	of_node_put(dn);
177 	if (!bus)
178 		return -EPROBE_DEFER;
179 
180 	phydev = phy_find_first(bus);
181 	put_device(&bus->dev);
182 	if (!phydev)
183 		return -EPROBE_DEFER;
184 
185 	register_reboot_notifier(&linkstation_reboot_nb);
186 	pm_power_off = linkstation_poweroff;
187 
188 	return 0;
189 }
190 
linkstation_poweroff_exit(void)191 static void __exit linkstation_poweroff_exit(void)
192 {
193 	pm_power_off = NULL;
194 	unregister_reboot_notifier(&linkstation_reboot_nb);
195 }
196 
197 module_init(linkstation_poweroff_init);
198 module_exit(linkstation_poweroff_exit);
199 
200 MODULE_AUTHOR("Daniel González Cabanelas <dgcbueu@gmail.com>");
201 MODULE_DESCRIPTION("LinkStation power off driver");
202 MODULE_LICENSE("GPL v2");
203