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11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/platform_device.h>
14#include <linux/list.h>
15#include <linux/mii.h>
16#include <linux/phy.h>
17#include <linux/phy_fixed.h>
18#include <linux/err.h>
19#include <linux/slab.h>
20#include <linux/of.h>
21#include <linux/gpio/consumer.h>
22#include <linux/idr.h>
23#include <linux/netdevice.h>
24#include <linux/linkmode.h>
25
26#include "swphy.h"
27
28struct fixed_mdio_bus {
29 struct mii_bus *mii_bus;
30 struct list_head phys;
31};
32
33struct fixed_phy {
34 int addr;
35 struct phy_device *phydev;
36 struct fixed_phy_status status;
37 bool no_carrier;
38 int (*link_update)(struct net_device *, struct fixed_phy_status *);
39 struct list_head node;
40 struct gpio_desc *link_gpiod;
41};
42
43static struct platform_device *pdev;
44static struct fixed_mdio_bus platform_fmb = {
45 .phys = LIST_HEAD_INIT(platform_fmb.phys),
46};
47
48int fixed_phy_change_carrier(struct net_device *dev, bool new_carrier)
49{
50 struct fixed_mdio_bus *fmb = &platform_fmb;
51 struct phy_device *phydev = dev->phydev;
52 struct fixed_phy *fp;
53
54 if (!phydev || !phydev->mdio.bus)
55 return -EINVAL;
56
57 list_for_each_entry(fp, &fmb->phys, node) {
58 if (fp->addr == phydev->mdio.addr) {
59 fp->no_carrier = !new_carrier;
60 return 0;
61 }
62 }
63 return -EINVAL;
64}
65EXPORT_SYMBOL_GPL(fixed_phy_change_carrier);
66
67static void fixed_phy_update(struct fixed_phy *fp)
68{
69 if (!fp->no_carrier && fp->link_gpiod)
70 fp->status.link = !!gpiod_get_value_cansleep(fp->link_gpiod);
71}
72
73static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num)
74{
75 struct fixed_mdio_bus *fmb = bus->priv;
76 struct fixed_phy *fp;
77
78 list_for_each_entry(fp, &fmb->phys, node) {
79 if (fp->addr == phy_addr) {
80 struct fixed_phy_status state;
81
82 fp->status.link = !fp->no_carrier;
83
84
85 if (fp->link_update)
86 fp->link_update(fp->phydev->attached_dev,
87 &fp->status);
88
89
90 fixed_phy_update(fp);
91 state = fp->status;
92
93 return swphy_read_reg(reg_num, &state);
94 }
95 }
96
97 return 0xFFFF;
98}
99
100static int fixed_mdio_write(struct mii_bus *bus, int phy_addr, int reg_num,
101 u16 val)
102{
103 return 0;
104}
105
106
107
108
109
110
111int fixed_phy_set_link_update(struct phy_device *phydev,
112 int (*link_update)(struct net_device *,
113 struct fixed_phy_status *))
114{
115 struct fixed_mdio_bus *fmb = &platform_fmb;
116 struct fixed_phy *fp;
117
118 if (!phydev || !phydev->mdio.bus)
119 return -EINVAL;
120
121 list_for_each_entry(fp, &fmb->phys, node) {
122 if (fp->addr == phydev->mdio.addr) {
123 fp->link_update = link_update;
124 fp->phydev = phydev;
125 return 0;
126 }
127 }
128
129 return -ENOENT;
130}
131EXPORT_SYMBOL_GPL(fixed_phy_set_link_update);
132
133static int fixed_phy_add_gpiod(unsigned int irq, int phy_addr,
134 struct fixed_phy_status *status,
135 struct gpio_desc *gpiod)
136{
137 int ret;
138 struct fixed_mdio_bus *fmb = &platform_fmb;
139 struct fixed_phy *fp;
140
141 ret = swphy_validate_state(status);
142 if (ret < 0)
143 return ret;
144
145 fp = kzalloc(sizeof(*fp), GFP_KERNEL);
146 if (!fp)
147 return -ENOMEM;
148
149 if (irq != PHY_POLL)
150 fmb->mii_bus->irq[phy_addr] = irq;
151
152 fp->addr = phy_addr;
153 fp->status = *status;
154 fp->link_gpiod = gpiod;
155
156 fixed_phy_update(fp);
157
158 list_add_tail(&fp->node, &fmb->phys);
159
160 return 0;
161}
162
163int fixed_phy_add(unsigned int irq, int phy_addr,
164 struct fixed_phy_status *status) {
165
166 return fixed_phy_add_gpiod(irq, phy_addr, status, NULL);
167}
168EXPORT_SYMBOL_GPL(fixed_phy_add);
169
170static DEFINE_IDA(phy_fixed_ida);
171
172static void fixed_phy_del(int phy_addr)
173{
174 struct fixed_mdio_bus *fmb = &platform_fmb;
175 struct fixed_phy *fp, *tmp;
176
177 list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
178 if (fp->addr == phy_addr) {
179 list_del(&fp->node);
180 if (fp->link_gpiod)
181 gpiod_put(fp->link_gpiod);
182 kfree(fp);
183 ida_simple_remove(&phy_fixed_ida, phy_addr);
184 return;
185 }
186 }
187}
188
189#ifdef CONFIG_OF_GPIO
190static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np)
191{
192 struct device_node *fixed_link_node;
193 struct gpio_desc *gpiod;
194
195 if (!np)
196 return NULL;
197
198 fixed_link_node = of_get_child_by_name(np, "fixed-link");
199 if (!fixed_link_node)
200 return NULL;
201
202
203
204
205
206
207 gpiod = fwnode_gpiod_get_index(of_fwnode_handle(fixed_link_node),
208 "link", 0, GPIOD_IN, "mdio");
209 if (IS_ERR(gpiod) && PTR_ERR(gpiod) != -EPROBE_DEFER) {
210 if (PTR_ERR(gpiod) != -ENOENT)
211 pr_err("error getting GPIO for fixed link %pOF, proceed without\n",
212 fixed_link_node);
213 gpiod = NULL;
214 }
215 of_node_put(fixed_link_node);
216
217 return gpiod;
218}
219#else
220static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np)
221{
222 return NULL;
223}
224#endif
225
226static struct phy_device *__fixed_phy_register(unsigned int irq,
227 struct fixed_phy_status *status,
228 struct device_node *np,
229 struct gpio_desc *gpiod)
230{
231 struct fixed_mdio_bus *fmb = &platform_fmb;
232 struct phy_device *phy;
233 int phy_addr;
234 int ret;
235
236 if (!fmb->mii_bus || fmb->mii_bus->state != MDIOBUS_REGISTERED)
237 return ERR_PTR(-EPROBE_DEFER);
238
239
240 if (!gpiod) {
241 gpiod = fixed_phy_get_gpiod(np);
242 if (IS_ERR(gpiod))
243 return ERR_CAST(gpiod);
244 }
245
246
247 phy_addr = ida_simple_get(&phy_fixed_ida, 0, PHY_MAX_ADDR, GFP_KERNEL);
248 if (phy_addr < 0)
249 return ERR_PTR(phy_addr);
250
251 ret = fixed_phy_add_gpiod(irq, phy_addr, status, gpiod);
252 if (ret < 0) {
253 ida_simple_remove(&phy_fixed_ida, phy_addr);
254 return ERR_PTR(ret);
255 }
256
257 phy = get_phy_device(fmb->mii_bus, phy_addr, false);
258 if (IS_ERR(phy)) {
259 fixed_phy_del(phy_addr);
260 return ERR_PTR(-EINVAL);
261 }
262
263
264 phy->link = status->link;
265 if (status->link) {
266 phy->speed = status->speed;
267 phy->duplex = status->duplex;
268 phy->pause = status->pause;
269 phy->asym_pause = status->asym_pause;
270 }
271
272 of_node_get(np);
273 phy->mdio.dev.of_node = np;
274 phy->is_pseudo_fixed_link = true;
275
276 switch (status->speed) {
277 case SPEED_1000:
278 linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
279 phy->supported);
280 linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
281 phy->supported);
282 fallthrough;
283 case SPEED_100:
284 linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Half_BIT,
285 phy->supported);
286 linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Full_BIT,
287 phy->supported);
288 fallthrough;
289 case SPEED_10:
290 default:
291 linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT,
292 phy->supported);
293 linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT,
294 phy->supported);
295 }
296
297 phy_advertise_supported(phy);
298
299 ret = phy_device_register(phy);
300 if (ret) {
301 phy_device_free(phy);
302 of_node_put(np);
303 fixed_phy_del(phy_addr);
304 return ERR_PTR(ret);
305 }
306
307 return phy;
308}
309
310struct phy_device *fixed_phy_register(unsigned int irq,
311 struct fixed_phy_status *status,
312 struct device_node *np)
313{
314 return __fixed_phy_register(irq, status, np, NULL);
315}
316EXPORT_SYMBOL_GPL(fixed_phy_register);
317
318struct phy_device *
319fixed_phy_register_with_gpiod(unsigned int irq,
320 struct fixed_phy_status *status,
321 struct gpio_desc *gpiod)
322{
323 return __fixed_phy_register(irq, status, NULL, gpiod);
324}
325EXPORT_SYMBOL_GPL(fixed_phy_register_with_gpiod);
326
327void fixed_phy_unregister(struct phy_device *phy)
328{
329 phy_device_remove(phy);
330 of_node_put(phy->mdio.dev.of_node);
331 fixed_phy_del(phy->mdio.addr);
332}
333EXPORT_SYMBOL_GPL(fixed_phy_unregister);
334
335static int __init fixed_mdio_bus_init(void)
336{
337 struct fixed_mdio_bus *fmb = &platform_fmb;
338 int ret;
339
340 pdev = platform_device_register_simple("Fixed MDIO bus", 0, NULL, 0);
341 if (IS_ERR(pdev))
342 return PTR_ERR(pdev);
343
344 fmb->mii_bus = mdiobus_alloc();
345 if (fmb->mii_bus == NULL) {
346 ret = -ENOMEM;
347 goto err_mdiobus_reg;
348 }
349
350 snprintf(fmb->mii_bus->id, MII_BUS_ID_SIZE, "fixed-0");
351 fmb->mii_bus->name = "Fixed MDIO Bus";
352 fmb->mii_bus->priv = fmb;
353 fmb->mii_bus->parent = &pdev->dev;
354 fmb->mii_bus->read = &fixed_mdio_read;
355 fmb->mii_bus->write = &fixed_mdio_write;
356
357 ret = mdiobus_register(fmb->mii_bus);
358 if (ret)
359 goto err_mdiobus_alloc;
360
361 return 0;
362
363err_mdiobus_alloc:
364 mdiobus_free(fmb->mii_bus);
365err_mdiobus_reg:
366 platform_device_unregister(pdev);
367 return ret;
368}
369module_init(fixed_mdio_bus_init);
370
371static void __exit fixed_mdio_bus_exit(void)
372{
373 struct fixed_mdio_bus *fmb = &platform_fmb;
374 struct fixed_phy *fp, *tmp;
375
376 mdiobus_unregister(fmb->mii_bus);
377 mdiobus_free(fmb->mii_bus);
378 platform_device_unregister(pdev);
379
380 list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
381 list_del(&fp->node);
382 kfree(fp);
383 }
384 ida_destroy(&phy_fixed_ida);
385}
386module_exit(fixed_mdio_bus_exit);
387
388MODULE_DESCRIPTION("Fixed MDIO bus (MDIO bus emulation with fixed PHYs)");
389MODULE_AUTHOR("Vitaly Bordug");
390MODULE_LICENSE("GPL");
391
