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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/seqlock.h>
23#include <linux/idr.h>
24#include <linux/netdevice.h>
25#include <linux/linkmode.h>
26
27#include "swphy.h"
28
29struct fixed_mdio_bus {
30 struct mii_bus *mii_bus;
31 struct list_head phys;
32};
33
34struct fixed_phy {
35 int addr;
36 struct phy_device *phydev;
37 seqcount_t seqcount;
38 struct fixed_phy_status status;
39 bool no_carrier;
40 int (*link_update)(struct net_device *, struct fixed_phy_status *);
41 struct list_head node;
42 struct gpio_desc *link_gpiod;
43};
44
45static struct platform_device *pdev;
46static struct fixed_mdio_bus platform_fmb = {
47 .phys = LIST_HEAD_INIT(platform_fmb.phys),
48};
49
50int fixed_phy_change_carrier(struct net_device *dev, bool new_carrier)
51{
52 struct fixed_mdio_bus *fmb = &platform_fmb;
53 struct phy_device *phydev = dev->phydev;
54 struct fixed_phy *fp;
55
56 if (!phydev || !phydev->mdio.bus)
57 return -EINVAL;
58
59 list_for_each_entry(fp, &fmb->phys, node) {
60 if (fp->addr == phydev->mdio.addr) {
61 fp->no_carrier = !new_carrier;
62 return 0;
63 }
64 }
65 return -EINVAL;
66}
67EXPORT_SYMBOL_GPL(fixed_phy_change_carrier);
68
69static void fixed_phy_update(struct fixed_phy *fp)
70{
71 if (!fp->no_carrier && fp->link_gpiod)
72 fp->status.link = !!gpiod_get_value_cansleep(fp->link_gpiod);
73}
74
75static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num)
76{
77 struct fixed_mdio_bus *fmb = bus->priv;
78 struct fixed_phy *fp;
79
80 list_for_each_entry(fp, &fmb->phys, node) {
81 if (fp->addr == phy_addr) {
82 struct fixed_phy_status state;
83 int s;
84
85 do {
86 s = read_seqcount_begin(&fp->seqcount);
87 fp->status.link = !fp->no_carrier;
88
89 if (fp->link_update)
90 fp->link_update(fp->phydev->attached_dev,
91 &fp->status);
92
93 fixed_phy_update(fp);
94 state = fp->status;
95 } while (read_seqcount_retry(&fp->seqcount, s));
96
97 return swphy_read_reg(reg_num, &state);
98 }
99 }
100
101 return 0xFFFF;
102}
103
104static int fixed_mdio_write(struct mii_bus *bus, int phy_addr, int reg_num,
105 u16 val)
106{
107 return 0;
108}
109
110
111
112
113
114
115int fixed_phy_set_link_update(struct phy_device *phydev,
116 int (*link_update)(struct net_device *,
117 struct fixed_phy_status *))
118{
119 struct fixed_mdio_bus *fmb = &platform_fmb;
120 struct fixed_phy *fp;
121
122 if (!phydev || !phydev->mdio.bus)
123 return -EINVAL;
124
125 list_for_each_entry(fp, &fmb->phys, node) {
126 if (fp->addr == phydev->mdio.addr) {
127 fp->link_update = link_update;
128 fp->phydev = phydev;
129 return 0;
130 }
131 }
132
133 return -ENOENT;
134}
135EXPORT_SYMBOL_GPL(fixed_phy_set_link_update);
136
137static int fixed_phy_add_gpiod(unsigned int irq, int phy_addr,
138 struct fixed_phy_status *status,
139 struct gpio_desc *gpiod)
140{
141 int ret;
142 struct fixed_mdio_bus *fmb = &platform_fmb;
143 struct fixed_phy *fp;
144
145 ret = swphy_validate_state(status);
146 if (ret < 0)
147 return ret;
148
149 fp = kzalloc(sizeof(*fp), GFP_KERNEL);
150 if (!fp)
151 return -ENOMEM;
152
153 seqcount_init(&fp->seqcount);
154
155 if (irq != PHY_POLL)
156 fmb->mii_bus->irq[phy_addr] = irq;
157
158 fp->addr = phy_addr;
159 fp->status = *status;
160 fp->link_gpiod = gpiod;
161
162 fixed_phy_update(fp);
163
164 list_add_tail(&fp->node, &fmb->phys);
165
166 return 0;
167}
168
169int fixed_phy_add(unsigned int irq, int phy_addr,
170 struct fixed_phy_status *status) {
171
172 return fixed_phy_add_gpiod(irq, phy_addr, status, NULL);
173}
174EXPORT_SYMBOL_GPL(fixed_phy_add);
175
176static DEFINE_IDA(phy_fixed_ida);
177
178static void fixed_phy_del(int phy_addr)
179{
180 struct fixed_mdio_bus *fmb = &platform_fmb;
181 struct fixed_phy *fp, *tmp;
182
183 list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
184 if (fp->addr == phy_addr) {
185 list_del(&fp->node);
186 if (fp->link_gpiod)
187 gpiod_put(fp->link_gpiod);
188 kfree(fp);
189 ida_simple_remove(&phy_fixed_ida, phy_addr);
190 return;
191 }
192 }
193}
194
195#ifdef CONFIG_OF_GPIO
196static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np)
197{
198 struct device_node *fixed_link_node;
199 struct gpio_desc *gpiod;
200
201 if (!np)
202 return NULL;
203
204 fixed_link_node = of_get_child_by_name(np, "fixed-link");
205 if (!fixed_link_node)
206 return NULL;
207
208
209
210
211
212
213 gpiod = gpiod_get_from_of_node(fixed_link_node, "link-gpios", 0,
214 GPIOD_IN, "mdio");
215 of_node_put(fixed_link_node);
216 if (IS_ERR(gpiod)) {
217 if (PTR_ERR(gpiod) == -EPROBE_DEFER)
218 return gpiod;
219 pr_err("error getting GPIO for fixed link %pOF, proceed without\n",
220 fixed_link_node);
221 gpiod = NULL;
222 }
223
224 return gpiod;
225}
226#else
227static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np)
228{
229 return NULL;
230}
231#endif
232
233static struct phy_device *__fixed_phy_register(unsigned int irq,
234 struct fixed_phy_status *status,
235 struct device_node *np,
236 struct gpio_desc *gpiod)
237{
238 struct fixed_mdio_bus *fmb = &platform_fmb;
239 struct phy_device *phy;
240 int phy_addr;
241 int ret;
242
243 if (!fmb->mii_bus || fmb->mii_bus->state != MDIOBUS_REGISTERED)
244 return ERR_PTR(-EPROBE_DEFER);
245
246
247 if (!gpiod) {
248 gpiod = fixed_phy_get_gpiod(np);
249 if (IS_ERR(gpiod))
250 return ERR_CAST(gpiod);
251 }
252
253
254 phy_addr = ida_simple_get(&phy_fixed_ida, 0, PHY_MAX_ADDR, GFP_KERNEL);
255 if (phy_addr < 0)
256 return ERR_PTR(phy_addr);
257
258 ret = fixed_phy_add_gpiod(irq, phy_addr, status, gpiod);
259 if (ret < 0) {
260 ida_simple_remove(&phy_fixed_ida, phy_addr);
261 return ERR_PTR(ret);
262 }
263
264 phy = get_phy_device(fmb->mii_bus, phy_addr, false);
265 if (IS_ERR(phy)) {
266 fixed_phy_del(phy_addr);
267 return ERR_PTR(-EINVAL);
268 }
269
270
271 phy->link = status->link;
272 if (status->link) {
273 phy->speed = status->speed;
274 phy->duplex = status->duplex;
275 phy->pause = status->pause;
276 phy->asym_pause = status->asym_pause;
277 }
278
279 of_node_get(np);
280 phy->mdio.dev.of_node = np;
281 phy->is_pseudo_fixed_link = true;
282
283 switch (status->speed) {
284 case SPEED_1000:
285 linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
286 phy->supported);
287 linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
288 phy->supported);
289
290 case SPEED_100:
291 linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Half_BIT,
292 phy->supported);
293 linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Full_BIT,
294 phy->supported);
295
296 case SPEED_10:
297 default:
298 linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT,
299 phy->supported);
300 linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT,
301 phy->supported);
302 }
303
304 phy_advertise_supported(phy);
305
306 ret = phy_device_register(phy);
307 if (ret) {
308 phy_device_free(phy);
309 of_node_put(np);
310 fixed_phy_del(phy_addr);
311 return ERR_PTR(ret);
312 }
313
314 return phy;
315}
316
317struct phy_device *fixed_phy_register(unsigned int irq,
318 struct fixed_phy_status *status,
319 struct device_node *np)
320{
321 return __fixed_phy_register(irq, status, np, NULL);
322}
323EXPORT_SYMBOL_GPL(fixed_phy_register);
324
325struct phy_device *
326fixed_phy_register_with_gpiod(unsigned int irq,
327 struct fixed_phy_status *status,
328 struct gpio_desc *gpiod)
329{
330 return __fixed_phy_register(irq, status, NULL, gpiod);
331}
332EXPORT_SYMBOL_GPL(fixed_phy_register_with_gpiod);
333
334void fixed_phy_unregister(struct phy_device *phy)
335{
336 phy_device_remove(phy);
337 of_node_put(phy->mdio.dev.of_node);
338 fixed_phy_del(phy->mdio.addr);
339}
340EXPORT_SYMBOL_GPL(fixed_phy_unregister);
341
342static int __init fixed_mdio_bus_init(void)
343{
344 struct fixed_mdio_bus *fmb = &platform_fmb;
345 int ret;
346
347 pdev = platform_device_register_simple("Fixed MDIO bus", 0, NULL, 0);
348 if (IS_ERR(pdev))
349 return PTR_ERR(pdev);
350
351 fmb->mii_bus = mdiobus_alloc();
352 if (fmb->mii_bus == NULL) {
353 ret = -ENOMEM;
354 goto err_mdiobus_reg;
355 }
356
357 snprintf(fmb->mii_bus->id, MII_BUS_ID_SIZE, "fixed-0");
358 fmb->mii_bus->name = "Fixed MDIO Bus";
359 fmb->mii_bus->priv = fmb;
360 fmb->mii_bus->parent = &pdev->dev;
361 fmb->mii_bus->read = &fixed_mdio_read;
362 fmb->mii_bus->write = &fixed_mdio_write;
363
364 ret = mdiobus_register(fmb->mii_bus);
365 if (ret)
366 goto err_mdiobus_alloc;
367
368 return 0;
369
370err_mdiobus_alloc:
371 mdiobus_free(fmb->mii_bus);
372err_mdiobus_reg:
373 platform_device_unregister(pdev);
374 return ret;
375}
376module_init(fixed_mdio_bus_init);
377
378static void __exit fixed_mdio_bus_exit(void)
379{
380 struct fixed_mdio_bus *fmb = &platform_fmb;
381 struct fixed_phy *fp, *tmp;
382
383 mdiobus_unregister(fmb->mii_bus);
384 mdiobus_free(fmb->mii_bus);
385 platform_device_unregister(pdev);
386
387 list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
388 list_del(&fp->node);
389 kfree(fp);
390 }
391 ida_destroy(&phy_fixed_ida);
392}
393module_exit(fixed_mdio_bus_exit);
394
395MODULE_DESCRIPTION("Fixed MDIO bus (MDIO bus emulation with fixed PHYs)");
396MODULE_AUTHOR("Vitaly Bordug");
397MODULE_LICENSE("GPL");
398
