summaryrefslogtreecommitdiff
path: root/drivers/net/phy/fixed_phy.c
blob: 4a3d34f40cb9f7844f3d05a767ff7deb43e9e540 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
// SPDX-License-Identifier: GPL-2.0+
/*
 * Fixed MDIO bus (MDIO bus emulation with fixed PHYs)
 *
 * Author: Vitaly Bordug <vbordug@ru.mvista.com>
 *         Anton Vorontsov <avorontsov@ru.mvista.com>
 *
 * Copyright (c) 2006-2007 MontaVista Software, Inc.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/list.h>
#include <linux/mii.h>
#include <linux/phy.h>
#include <linux/phy_fixed.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <linux/seqlock.h>
#include <linux/idr.h>
#include <linux/netdevice.h>
#include <linux/linkmode.h>

#include "swphy.h"

struct fixed_mdio_bus {
	struct mii_bus *mii_bus;
	struct list_head phys;
};

struct fixed_phy {
	int addr;
	struct phy_device *phydev;
	seqcount_t seqcount;
	struct fixed_phy_status status;
	bool no_carrier;
	int (*link_update)(struct net_device *, struct fixed_phy_status *);
	struct list_head node;
	struct gpio_desc *link_gpiod;
};

static struct platform_device *pdev;
static struct fixed_mdio_bus platform_fmb = {
	.phys = LIST_HEAD_INIT(platform_fmb.phys),
};

int fixed_phy_change_carrier(struct net_device *dev, bool new_carrier)
{
	struct fixed_mdio_bus *fmb = &platform_fmb;
	struct phy_device *phydev = dev->phydev;
	struct fixed_phy *fp;

	if (!phydev || !phydev->mdio.bus)
		return -EINVAL;

	list_for_each_entry(fp, &fmb->phys, node) {
		if (fp->addr == phydev->mdio.addr) {
			fp->no_carrier = !new_carrier;
			return 0;
		}
	}
	return -EINVAL;
}
EXPORT_SYMBOL_GPL(fixed_phy_change_carrier);

static void fixed_phy_update(struct fixed_phy *fp)
{
	if (!fp->no_carrier && fp->link_gpiod)
		fp->status.link = !!gpiod_get_value_cansleep(fp->link_gpiod);
}

static int fixed_mdio_read(struct mii_bus *bus, int phy_addr, int reg_num)
{
	struct fixed_mdio_bus *fmb = bus->priv;
	struct fixed_phy *fp;

	list_for_each_entry(fp, &fmb->phys, node) {
		if (fp->addr == phy_addr) {
			struct fixed_phy_status state;
			int s;

			do {
				s = read_seqcount_begin(&fp->seqcount);
				fp->status.link = !fp->no_carrier;
				/* Issue callback if user registered it. */
				if (fp->link_update)
					fp->link_update(fp->phydev->attached_dev,
							&fp->status);
				/* Check the GPIO for change in status */
				fixed_phy_update(fp);
				state = fp->status;
			} while (read_seqcount_retry(&fp->seqcount, s));

			return swphy_read_reg(reg_num, &state);
		}
	}

	return 0xFFFF;
}

static int fixed_mdio_write(struct mii_bus *bus, int phy_addr, int reg_num,
			    u16 val)
{
	return 0;
}

/*
 * If something weird is required to be done with link/speed,
 * network driver is able to assign a function to implement this.
 * May be useful for PHY's that need to be software-driven.
 */
int fixed_phy_set_link_update(struct phy_device *phydev,
			      int (*link_update)(struct net_device *,
						 struct fixed_phy_status *))
{
	struct fixed_mdio_bus *fmb = &platform_fmb;
	struct fixed_phy *fp;

	if (!phydev || !phydev->mdio.bus)
		return -EINVAL;

	list_for_each_entry(fp, &fmb->phys, node) {
		if (fp->addr == phydev->mdio.addr) {
			fp->link_update = link_update;
			fp->phydev = phydev;
			return 0;
		}
	}

	return -ENOENT;
}
EXPORT_SYMBOL_GPL(fixed_phy_set_link_update);

static int fixed_phy_add_gpiod(unsigned int irq, int phy_addr,
			       struct fixed_phy_status *status,
			       struct gpio_desc *gpiod)
{
	int ret;
	struct fixed_mdio_bus *fmb = &platform_fmb;
	struct fixed_phy *fp;

	ret = swphy_validate_state(status);
	if (ret < 0)
		return ret;

	fp = kzalloc(sizeof(*fp), GFP_KERNEL);
	if (!fp)
		return -ENOMEM;

	seqcount_init(&fp->seqcount);

	if (irq != PHY_POLL)
		fmb->mii_bus->irq[phy_addr] = irq;

	fp->addr = phy_addr;
	fp->status = *status;
	fp->link_gpiod = gpiod;

	fixed_phy_update(fp);

	list_add_tail(&fp->node, &fmb->phys);

	return 0;
}

int fixed_phy_add(unsigned int irq, int phy_addr,
		  struct fixed_phy_status *status) {

	return fixed_phy_add_gpiod(irq, phy_addr, status, NULL);
}
EXPORT_SYMBOL_GPL(fixed_phy_add);

static DEFINE_IDA(phy_fixed_ida);

static void fixed_phy_del(int phy_addr)
{
	struct fixed_mdio_bus *fmb = &platform_fmb;
	struct fixed_phy *fp, *tmp;

	list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
		if (fp->addr == phy_addr) {
			list_del(&fp->node);
			if (fp->link_gpiod)
				gpiod_put(fp->link_gpiod);
			kfree(fp);
			ida_simple_remove(&phy_fixed_ida, phy_addr);
			return;
		}
	}
}

#ifdef CONFIG_OF_GPIO
static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np)
{
	struct device_node *fixed_link_node;
	struct gpio_desc *gpiod;

	if (!np)
		return NULL;

	fixed_link_node = of_get_child_by_name(np, "fixed-link");
	if (!fixed_link_node)
		return NULL;

	/*
	 * As the fixed link is just a device tree node without any
	 * Linux device associated with it, we simply have obtain
	 * the GPIO descriptor from the device tree like this.
	 */
	gpiod = fwnode_gpiod_get_index(of_fwnode_handle(fixed_link_node),
				       "link", 0, GPIOD_IN, "mdio");
	if (IS_ERR(gpiod) && PTR_ERR(gpiod) != -EPROBE_DEFER) {
		if (PTR_ERR(gpiod) != -ENOENT)
			pr_err("error getting GPIO for fixed link %pOF, proceed without\n",
			       fixed_link_node);
		gpiod = NULL;
	}
	of_node_put(fixed_link_node);

	return gpiod;
}
#else
static struct gpio_desc *fixed_phy_get_gpiod(struct device_node *np)
{
	return NULL;
}
#endif

static struct phy_device *__fixed_phy_register(unsigned int irq,
					       struct fixed_phy_status *status,
					       struct device_node *np,
					       struct gpio_desc *gpiod)
{
	struct fixed_mdio_bus *fmb = &platform_fmb;
	struct phy_device *phy;
	int phy_addr;
	int ret;

	if (!fmb->mii_bus || fmb->mii_bus->state != MDIOBUS_REGISTERED)
		return ERR_PTR(-EPROBE_DEFER);

	/* Check if we have a GPIO associated with this fixed phy */
	if (!gpiod) {
		gpiod = fixed_phy_get_gpiod(np);
		if (IS_ERR(gpiod))
			return ERR_CAST(gpiod);
	}

	/* Get the next available PHY address, up to PHY_MAX_ADDR */
	phy_addr = ida_simple_get(&phy_fixed_ida, 0, PHY_MAX_ADDR, GFP_KERNEL);
	if (phy_addr < 0)
		return ERR_PTR(phy_addr);

	ret = fixed_phy_add_gpiod(irq, phy_addr, status, gpiod);
	if (ret < 0) {
		ida_simple_remove(&phy_fixed_ida, phy_addr);
		return ERR_PTR(ret);
	}

	phy = get_phy_device(fmb->mii_bus, phy_addr, false);
	if (IS_ERR(phy)) {
		fixed_phy_del(phy_addr);
		return ERR_PTR(-EINVAL);
	}

	/* propagate the fixed link values to struct phy_device */
	phy->link = status->link;
	if (status->link) {
		phy->speed = status->speed;
		phy->duplex = status->duplex;
		phy->pause = status->pause;
		phy->asym_pause = status->asym_pause;
	}

	of_node_get(np);
	phy->mdio.dev.of_node = np;
	phy->is_pseudo_fixed_link = true;

	switch (status->speed) {
	case SPEED_1000:
		linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
				 phy->supported);
		linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
				 phy->supported);
		/* fall through */
	case SPEED_100:
		linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Half_BIT,
				 phy->supported);
		linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Full_BIT,
				 phy->supported);
		/* fall through */
	case SPEED_10:
	default:
		linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Half_BIT,
				 phy->supported);
		linkmode_set_bit(ETHTOOL_LINK_MODE_10baseT_Full_BIT,
				 phy->supported);
	}

	phy_advertise_supported(phy);

	ret = phy_device_register(phy);
	if (ret) {
		phy_device_free(phy);
		of_node_put(np);
		fixed_phy_del(phy_addr);
		return ERR_PTR(ret);
	}

	return phy;
}

struct phy_device *fixed_phy_register(unsigned int irq,
				      struct fixed_phy_status *status,
				      struct device_node *np)
{
	return __fixed_phy_register(irq, status, np, NULL);
}
EXPORT_SYMBOL_GPL(fixed_phy_register);

struct phy_device *
fixed_phy_register_with_gpiod(unsigned int irq,
			      struct fixed_phy_status *status,
			      struct gpio_desc *gpiod)
{
	return __fixed_phy_register(irq, status, NULL, gpiod);
}
EXPORT_SYMBOL_GPL(fixed_phy_register_with_gpiod);

void fixed_phy_unregister(struct phy_device *phy)
{
	phy_device_remove(phy);
	of_node_put(phy->mdio.dev.of_node);
	fixed_phy_del(phy->mdio.addr);
}
EXPORT_SYMBOL_GPL(fixed_phy_unregister);

static int __init fixed_mdio_bus_init(void)
{
	struct fixed_mdio_bus *fmb = &platform_fmb;
	int ret;

	pdev = platform_device_register_simple("Fixed MDIO bus", 0, NULL, 0);
	if (IS_ERR(pdev))
		return PTR_ERR(pdev);

	fmb->mii_bus = mdiobus_alloc();
	if (fmb->mii_bus == NULL) {
		ret = -ENOMEM;
		goto err_mdiobus_reg;
	}

	snprintf(fmb->mii_bus->id, MII_BUS_ID_SIZE, "fixed-0");
	fmb->mii_bus->name = "Fixed MDIO Bus";
	fmb->mii_bus->priv = fmb;
	fmb->mii_bus->parent = &pdev->dev;
	fmb->mii_bus->read = &fixed_mdio_read;
	fmb->mii_bus->write = &fixed_mdio_write;

	ret = mdiobus_register(fmb->mii_bus);
	if (ret)
		goto err_mdiobus_alloc;

	return 0;

err_mdiobus_alloc:
	mdiobus_free(fmb->mii_bus);
err_mdiobus_reg:
	platform_device_unregister(pdev);
	return ret;
}
module_init(fixed_mdio_bus_init);

static void __exit fixed_mdio_bus_exit(void)
{
	struct fixed_mdio_bus *fmb = &platform_fmb;
	struct fixed_phy *fp, *tmp;

	mdiobus_unregister(fmb->mii_bus);
	mdiobus_free(fmb->mii_bus);
	platform_device_unregister(pdev);

	list_for_each_entry_safe(fp, tmp, &fmb->phys, node) {
		list_del(&fp->node);
		kfree(fp);
	}
	ida_destroy(&phy_fixed_ida);
}
module_exit(fixed_mdio_bus_exit);

MODULE_DESCRIPTION("Fixed MDIO bus (MDIO bus emulation with fixed PHYs)");
MODULE_AUTHOR("Vitaly Bordug");
MODULE_LICENSE("GPL");