1 // SPDX-License-Identifier: GPL-2.0+
2 /* Framework for MDIO devices, other than PHYs.
3 *
4 * Copyright (c) 2016 Andrew Lunn <andrew@lunn.ch>
5 */
6
7 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
8
9 #include <linux/delay.h>
10 #include <linux/errno.h>
11 #include <linux/gpio.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/kernel.h>
16 #include <linux/mdio.h>
17 #include <linux/mii.h>
18 #include <linux/module.h>
19 #include <linux/phy.h>
20 #include <linux/reset.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23 #include <linux/unistd.h>
24 #include <linux/property.h>
25
mdio_device_free(struct mdio_device * mdiodev)26 void mdio_device_free(struct mdio_device *mdiodev)
27 {
28 put_device(&mdiodev->dev);
29 }
30 EXPORT_SYMBOL(mdio_device_free);
31
mdio_device_release(struct device * dev)32 static void mdio_device_release(struct device *dev)
33 {
34 fwnode_handle_put(dev->fwnode);
35 kfree(to_mdio_device(dev));
36 }
37
mdio_device_bus_match(struct device * dev,struct device_driver * drv)38 int mdio_device_bus_match(struct device *dev, struct device_driver *drv)
39 {
40 struct mdio_device *mdiodev = to_mdio_device(dev);
41 struct mdio_driver *mdiodrv = to_mdio_driver(drv);
42
43 if (mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY)
44 return 0;
45
46 return strcmp(mdiodev->modalias, drv->name) == 0;
47 }
48
mdio_device_create(struct mii_bus * bus,int addr)49 struct mdio_device *mdio_device_create(struct mii_bus *bus, int addr)
50 {
51 struct mdio_device *mdiodev;
52
53 /* We allocate the device, and initialize the default values */
54 mdiodev = kzalloc(sizeof(*mdiodev), GFP_KERNEL);
55 if (!mdiodev)
56 return ERR_PTR(-ENOMEM);
57
58 mdiodev->dev.release = mdio_device_release;
59 mdiodev->dev.parent = &bus->dev;
60 mdiodev->dev.bus = &mdio_bus_type;
61 mdiodev->device_free = mdio_device_free;
62 mdiodev->device_remove = mdio_device_remove;
63 mdiodev->bus = bus;
64 mdiodev->addr = addr;
65
66 dev_set_name(&mdiodev->dev, PHY_ID_FMT, bus->id, addr);
67
68 device_initialize(&mdiodev->dev);
69
70 return mdiodev;
71 }
72 EXPORT_SYMBOL(mdio_device_create);
73
74 /**
75 * mdio_device_register - Register the mdio device on the MDIO bus
76 * @mdiodev: mdio_device structure to be added to the MDIO bus
77 */
mdio_device_register(struct mdio_device * mdiodev)78 int mdio_device_register(struct mdio_device *mdiodev)
79 {
80 int err;
81
82 dev_dbg(&mdiodev->dev, "%s\n", __func__);
83
84 err = mdiobus_register_device(mdiodev);
85 if (err)
86 return err;
87
88 err = device_add(&mdiodev->dev);
89 if (err) {
90 pr_err("MDIO %d failed to add\n", mdiodev->addr);
91 goto out;
92 }
93
94 return 0;
95
96 out:
97 mdiobus_unregister_device(mdiodev);
98 return err;
99 }
100 EXPORT_SYMBOL(mdio_device_register);
101
102 /**
103 * mdio_device_remove - Remove a previously registered mdio device from the
104 * MDIO bus
105 * @mdiodev: mdio_device structure to remove
106 *
107 * This doesn't free the mdio_device itself, it merely reverses the effects
108 * of mdio_device_register(). Use mdio_device_free() to free the device
109 * after calling this function.
110 */
mdio_device_remove(struct mdio_device * mdiodev)111 void mdio_device_remove(struct mdio_device *mdiodev)
112 {
113 device_del(&mdiodev->dev);
114 mdiobus_unregister_device(mdiodev);
115 }
116 EXPORT_SYMBOL(mdio_device_remove);
117
mdio_device_reset(struct mdio_device * mdiodev,int value)118 void mdio_device_reset(struct mdio_device *mdiodev, int value)
119 {
120 unsigned int d;
121
122 if (!mdiodev->reset_gpio && !mdiodev->reset_ctrl)
123 return;
124
125 if (mdiodev->reset_gpio)
126 gpiod_set_value_cansleep(mdiodev->reset_gpio, value);
127
128 if (mdiodev->reset_ctrl) {
129 if (value)
130 reset_control_assert(mdiodev->reset_ctrl);
131 else
132 reset_control_deassert(mdiodev->reset_ctrl);
133 }
134
135 d = value ? mdiodev->reset_assert_delay : mdiodev->reset_deassert_delay;
136 if (d)
137 fsleep(d);
138 }
139 EXPORT_SYMBOL(mdio_device_reset);
140
141 /**
142 * mdio_probe - probe an MDIO device
143 * @dev: device to probe
144 *
145 * Description: Take care of setting up the mdio_device structure
146 * and calling the driver to probe the device.
147 */
mdio_probe(struct device * dev)148 static int mdio_probe(struct device *dev)
149 {
150 struct mdio_device *mdiodev = to_mdio_device(dev);
151 struct device_driver *drv = mdiodev->dev.driver;
152 struct mdio_driver *mdiodrv = to_mdio_driver(drv);
153 int err = 0;
154
155 /* Deassert the reset signal */
156 mdio_device_reset(mdiodev, 0);
157
158 if (mdiodrv->probe) {
159 err = mdiodrv->probe(mdiodev);
160 if (err) {
161 /* Assert the reset signal */
162 mdio_device_reset(mdiodev, 1);
163 }
164 }
165
166 return err;
167 }
168
mdio_remove(struct device * dev)169 static int mdio_remove(struct device *dev)
170 {
171 struct mdio_device *mdiodev = to_mdio_device(dev);
172 struct device_driver *drv = mdiodev->dev.driver;
173 struct mdio_driver *mdiodrv = to_mdio_driver(drv);
174
175 if (mdiodrv->remove)
176 mdiodrv->remove(mdiodev);
177
178 /* Assert the reset signal */
179 mdio_device_reset(mdiodev, 1);
180
181 return 0;
182 }
183
mdio_shutdown(struct device * dev)184 static void mdio_shutdown(struct device *dev)
185 {
186 struct mdio_device *mdiodev = to_mdio_device(dev);
187 struct device_driver *drv = mdiodev->dev.driver;
188 struct mdio_driver *mdiodrv = to_mdio_driver(drv);
189
190 if (mdiodrv->shutdown)
191 mdiodrv->shutdown(mdiodev);
192 }
193
194 /**
195 * mdio_driver_register - register an mdio_driver with the MDIO layer
196 * @drv: new mdio_driver to register
197 */
mdio_driver_register(struct mdio_driver * drv)198 int mdio_driver_register(struct mdio_driver *drv)
199 {
200 struct mdio_driver_common *mdiodrv = &drv->mdiodrv;
201 int retval;
202
203 pr_debug("%s: %s\n", __func__, mdiodrv->driver.name);
204
205 mdiodrv->driver.bus = &mdio_bus_type;
206 mdiodrv->driver.probe = mdio_probe;
207 mdiodrv->driver.remove = mdio_remove;
208 mdiodrv->driver.shutdown = mdio_shutdown;
209
210 retval = driver_register(&mdiodrv->driver);
211 if (retval) {
212 pr_err("%s: Error %d in registering driver\n",
213 mdiodrv->driver.name, retval);
214
215 return retval;
216 }
217
218 return 0;
219 }
220 EXPORT_SYMBOL(mdio_driver_register);
221
mdio_driver_unregister(struct mdio_driver * drv)222 void mdio_driver_unregister(struct mdio_driver *drv)
223 {
224 struct mdio_driver_common *mdiodrv = &drv->mdiodrv;
225
226 driver_unregister(&mdiodrv->driver);
227 }
228 EXPORT_SYMBOL(mdio_driver_unregister);
229