1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * fwnode helpers for the MDIO (Ethernet PHY) API
4  *
5  * This file provides helper functions for extracting PHY device information
6  * out of the fwnode and using it to populate an mii_bus.
7  */
8 
9 #include <linux/acpi.h>
10 #include <linux/fwnode_mdio.h>
11 #include <linux/of.h>
12 #include <linux/phy.h>
13 #include <linux/pse-pd/pse.h>
14 
15 MODULE_AUTHOR("Calvin Johnson <calvin.johnson@oss.nxp.com>");
16 MODULE_LICENSE("GPL");
17 
18 static struct pse_control *
fwnode_find_pse_control(struct fwnode_handle * fwnode)19 fwnode_find_pse_control(struct fwnode_handle *fwnode)
20 {
21 	struct pse_control *psec;
22 	struct device_node *np;
23 
24 	if (!IS_ENABLED(CONFIG_PSE_CONTROLLER))
25 		return NULL;
26 
27 	np = to_of_node(fwnode);
28 	if (!np)
29 		return NULL;
30 
31 	psec = of_pse_control_get(np);
32 	if (PTR_ERR(psec) == -ENOENT)
33 		return NULL;
34 
35 	return psec;
36 }
37 
38 static struct mii_timestamper *
fwnode_find_mii_timestamper(struct fwnode_handle * fwnode)39 fwnode_find_mii_timestamper(struct fwnode_handle *fwnode)
40 {
41 	struct of_phandle_args arg;
42 	int err;
43 
44 	if (is_acpi_node(fwnode))
45 		return NULL;
46 
47 	err = of_parse_phandle_with_fixed_args(to_of_node(fwnode),
48 					       "timestamper", 1, 0, &arg);
49 	if (err == -ENOENT)
50 		return NULL;
51 	else if (err)
52 		return ERR_PTR(err);
53 
54 	if (arg.args_count != 1)
55 		return ERR_PTR(-EINVAL);
56 
57 	return register_mii_timestamper(arg.np, arg.args[0]);
58 }
59 
fwnode_mdiobus_phy_device_register(struct mii_bus * mdio,struct phy_device * phy,struct fwnode_handle * child,u32 addr)60 int fwnode_mdiobus_phy_device_register(struct mii_bus *mdio,
61 				       struct phy_device *phy,
62 				       struct fwnode_handle *child, u32 addr)
63 {
64 	int rc;
65 
66 	rc = fwnode_irq_get(child, 0);
67 	/* Don't wait forever if the IRQ provider doesn't become available,
68 	 * just fall back to poll mode
69 	 */
70 	if (rc == -EPROBE_DEFER)
71 		rc = driver_deferred_probe_check_state(&phy->mdio.dev);
72 	if (rc == -EPROBE_DEFER)
73 		return rc;
74 
75 	if (rc > 0) {
76 		phy->irq = rc;
77 		mdio->irq[addr] = rc;
78 	} else {
79 		phy->irq = mdio->irq[addr];
80 	}
81 
82 	if (fwnode_property_read_bool(child, "broken-turn-around"))
83 		mdio->phy_ignore_ta_mask |= 1 << addr;
84 
85 	fwnode_property_read_u32(child, "reset-assert-us",
86 				 &phy->mdio.reset_assert_delay);
87 	fwnode_property_read_u32(child, "reset-deassert-us",
88 				 &phy->mdio.reset_deassert_delay);
89 
90 	/* Associate the fwnode with the device structure so it
91 	 * can be looked up later
92 	 */
93 	fwnode_handle_get(child);
94 	device_set_node(&phy->mdio.dev, child);
95 
96 	/* All data is now stored in the phy struct;
97 	 * register it
98 	 */
99 	rc = phy_device_register(phy);
100 	if (rc) {
101 		device_set_node(&phy->mdio.dev, NULL);
102 		fwnode_handle_put(child);
103 		return rc;
104 	}
105 
106 	dev_dbg(&mdio->dev, "registered phy %p fwnode at address %i\n",
107 		child, addr);
108 	return 0;
109 }
110 EXPORT_SYMBOL(fwnode_mdiobus_phy_device_register);
111 
fwnode_mdiobus_register_phy(struct mii_bus * bus,struct fwnode_handle * child,u32 addr)112 int fwnode_mdiobus_register_phy(struct mii_bus *bus,
113 				struct fwnode_handle *child, u32 addr)
114 {
115 	struct mii_timestamper *mii_ts = NULL;
116 	struct pse_control *psec = NULL;
117 	struct phy_device *phy;
118 	bool is_c45;
119 	u32 phy_id;
120 	int rc;
121 
122 	psec = fwnode_find_pse_control(child);
123 	if (IS_ERR(psec))
124 		return PTR_ERR(psec);
125 
126 	mii_ts = fwnode_find_mii_timestamper(child);
127 	if (IS_ERR(mii_ts)) {
128 		rc = PTR_ERR(mii_ts);
129 		goto clean_pse;
130 	}
131 
132 	is_c45 = fwnode_device_is_compatible(child, "ethernet-phy-ieee802.3-c45");
133 	if (is_c45 || fwnode_get_phy_id(child, &phy_id))
134 		phy = get_phy_device(bus, addr, is_c45);
135 	else
136 		phy = phy_device_create(bus, addr, phy_id, 0, NULL);
137 	if (IS_ERR(phy)) {
138 		rc = PTR_ERR(phy);
139 		goto clean_mii_ts;
140 	}
141 
142 	if (is_acpi_node(child)) {
143 		phy->irq = bus->irq[addr];
144 
145 		/* Associate the fwnode with the device structure so it
146 		 * can be looked up later.
147 		 */
148 		phy->mdio.dev.fwnode = fwnode_handle_get(child);
149 
150 		/* All data is now stored in the phy struct, so register it */
151 		rc = phy_device_register(phy);
152 		if (rc) {
153 			phy->mdio.dev.fwnode = NULL;
154 			fwnode_handle_put(child);
155 			goto clean_phy;
156 		}
157 	} else if (is_of_node(child)) {
158 		rc = fwnode_mdiobus_phy_device_register(bus, phy, child, addr);
159 		if (rc)
160 			goto clean_phy;
161 	}
162 
163 	phy->psec = psec;
164 
165 	/* phy->mii_ts may already be defined by the PHY driver. A
166 	 * mii_timestamper probed via the device tree will still have
167 	 * precedence.
168 	 */
169 	if (mii_ts)
170 		phy->mii_ts = mii_ts;
171 
172 	return 0;
173 
174 clean_phy:
175 	phy_device_free(phy);
176 clean_mii_ts:
177 	unregister_mii_timestamper(mii_ts);
178 clean_pse:
179 	pse_control_put(psec);
180 
181 	return rc;
182 }
183 EXPORT_SYMBOL(fwnode_mdiobus_register_phy);
184