1// SPDX-License-Identifier: GPL-2.0
2/*
3 * LinkStation power off restart driver
4 * Copyright (C) 2020 Daniel Gonz��lez 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
35struct power_off_cfg {
36	char *mdio_node_name;
37	void (*phy_set_reg)(bool restart);
38};
39
40static struct phy_device *phydev;
41static const struct power_off_cfg *cfg;
42
43static 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	}
76err:
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
82static 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	}
107err:
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
113static const struct power_off_cfg linkstation_power_off_cfg = {
114	.mdio_node_name = "mdio",
115	.phy_set_reg = linkstation_mvphy_reg_intn,
116};
117
118static 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
123static 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
132static struct notifier_block linkstation_reboot_nb = {
133	.notifier_call = linkstation_reboot_notifier,
134};
135
136static 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
144static 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
157static 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
191static void __exit linkstation_poweroff_exit(void)
192{
193	pm_power_off = NULL;
194	unregister_reboot_notifier(&linkstation_reboot_nb);
195}
196
197module_init(linkstation_poweroff_init);
198module_exit(linkstation_poweroff_exit);
199
200MODULE_AUTHOR("Daniel Gonz��lez Cabanelas <dgcbueu@gmail.com>");
201MODULE_DESCRIPTION("LinkStation power off driver");
202MODULE_LICENSE("GPL v2");
203