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v4.17
 
  1/*
  2 * DaVinci MDIO Module driver
  3 *
  4 * Copyright (C) 2010 Texas Instruments.
  5 *
  6 * Shamelessly ripped out of davinci_emac.c, original copyrights follow:
  7 *
  8 * Copyright (C) 2009 Texas Instruments.
  9 *
 10 * ---------------------------------------------------------------------------
 11 *
 12 * This program is free software; you can redistribute it and/or modify
 13 * it under the terms of the GNU General Public License as published by
 14 * the Free Software Foundation; either version 2 of the License, or
 15 * (at your option) any later version.
 16 *
 17 * This program is distributed in the hope that it will be useful,
 18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 20 * GNU General Public License for more details.
 21 *
 22 * You should have received a copy of the GNU General Public License
 23 * along with this program; if not, write to the Free Software
 24 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 25 * ---------------------------------------------------------------------------
 26 */
 27#include <linux/module.h>
 28#include <linux/kernel.h>
 29#include <linux/platform_device.h>
 30#include <linux/delay.h>
 31#include <linux/sched.h>
 32#include <linux/slab.h>
 33#include <linux/phy.h>
 34#include <linux/clk.h>
 35#include <linux/err.h>
 36#include <linux/io.h>
 
 37#include <linux/pm_runtime.h>
 38#include <linux/davinci_emac.h>
 39#include <linux/of.h>
 40#include <linux/of_device.h>
 41#include <linux/of_mdio.h>
 42#include <linux/pinctrl/consumer.h>
 43
 44/*
 45 * This timeout definition is a worst-case ultra defensive measure against
 46 * unexpected controller lock ups.  Ideally, we should never ever hit this
 47 * scenario in practice.
 48 */
 49#define MDIO_TIMEOUT		100 /* msecs */
 50
 51#define PHY_REG_MASK		0x1f
 52#define PHY_ID_MASK		0x1f
 53
 54#define DEF_OUT_FREQ		2200000		/* 2.2 MHz */
 55
 56struct davinci_mdio_of_param {
 57	int autosuspend_delay_ms;
 58};
 59
 60struct davinci_mdio_regs {
 61	u32	version;
 62	u32	control;
 63#define CONTROL_IDLE		BIT(31)
 64#define CONTROL_ENABLE		BIT(30)
 65#define CONTROL_MAX_DIV		(0xffff)
 66
 67	u32	alive;
 68	u32	link;
 69	u32	linkintraw;
 70	u32	linkintmasked;
 71	u32	__reserved_0[2];
 72	u32	userintraw;
 73	u32	userintmasked;
 74	u32	userintmaskset;
 75	u32	userintmaskclr;
 76	u32	__reserved_1[20];
 77
 78	struct {
 79		u32	access;
 80#define USERACCESS_GO		BIT(31)
 81#define USERACCESS_WRITE	BIT(30)
 82#define USERACCESS_ACK		BIT(29)
 83#define USERACCESS_READ		(0)
 84#define USERACCESS_DATA		(0xffff)
 85
 86		u32	physel;
 87	}	user[0];
 88};
 89
 90static const struct mdio_platform_data default_pdata = {
 91	.bus_freq = DEF_OUT_FREQ,
 92};
 93
 94struct davinci_mdio_data {
 95	struct mdio_platform_data pdata;
 96	struct davinci_mdio_regs __iomem *regs;
 97	struct clk	*clk;
 98	struct device	*dev;
 99	struct mii_bus	*bus;
100	bool            active_in_suspend;
101	unsigned long	access_time; /* jiffies */
102	/* Indicates that driver shouldn't modify phy_mask in case
103	 * if MDIO bus is registered from DT.
104	 */
105	bool		skip_scan;
106	u32		clk_div;
107};
108
109static void davinci_mdio_init_clk(struct davinci_mdio_data *data)
110{
111	u32 mdio_in, div, mdio_out_khz, access_time;
112
113	mdio_in = clk_get_rate(data->clk);
114	div = (mdio_in / data->pdata.bus_freq) - 1;
115	if (div > CONTROL_MAX_DIV)
116		div = CONTROL_MAX_DIV;
117
118	data->clk_div = div;
119	/*
120	 * One mdio transaction consists of:
121	 *	32 bits of preamble
122	 *	32 bits of transferred data
123	 *	24 bits of bus yield (not needed unless shared?)
124	 */
125	mdio_out_khz = mdio_in / (1000 * (div + 1));
126	access_time  = (88 * 1000) / mdio_out_khz;
127
128	/*
129	 * In the worst case, we could be kicking off a user-access immediately
130	 * after the mdio bus scan state-machine triggered its own read.  If
131	 * so, our request could get deferred by one access cycle.  We
132	 * defensively allow for 4 access cycles.
133	 */
134	data->access_time = usecs_to_jiffies(access_time * 4);
135	if (!data->access_time)
136		data->access_time = 1;
137}
138
139static void davinci_mdio_enable(struct davinci_mdio_data *data)
140{
141	/* set enable and clock divider */
142	__raw_writel(data->clk_div | CONTROL_ENABLE, &data->regs->control);
143}
144
145static int davinci_mdio_reset(struct mii_bus *bus)
146{
147	struct davinci_mdio_data *data = bus->priv;
148	u32 phy_mask, ver;
149	int ret;
150
151	ret = pm_runtime_get_sync(data->dev);
152	if (ret < 0) {
153		pm_runtime_put_noidle(data->dev);
154		return ret;
155	}
156
157	/* wait for scan logic to settle */
158	msleep(PHY_MAX_ADDR * data->access_time);
159
160	/* dump hardware version info */
161	ver = __raw_readl(&data->regs->version);
162	dev_info(data->dev,
163		 "davinci mdio revision %d.%d, bus freq %ld\n",
164		 (ver >> 8) & 0xff, ver & 0xff,
165		 data->pdata.bus_freq);
166
167	if (data->skip_scan)
168		goto done;
169
170	/* get phy mask from the alive register */
171	phy_mask = __raw_readl(&data->regs->alive);
172	if (phy_mask) {
173		/* restrict mdio bus to live phys only */
174		dev_info(data->dev, "detected phy mask %x\n", ~phy_mask);
175		phy_mask = ~phy_mask;
176	} else {
177		/* desperately scan all phys */
178		dev_warn(data->dev, "no live phy, scanning all\n");
179		phy_mask = 0;
180	}
181	data->bus->phy_mask = phy_mask;
182
183done:
184	pm_runtime_mark_last_busy(data->dev);
185	pm_runtime_put_autosuspend(data->dev);
186
187	return 0;
188}
189
190/* wait until hardware is ready for another user access */
191static inline int wait_for_user_access(struct davinci_mdio_data *data)
192{
193	struct davinci_mdio_regs __iomem *regs = data->regs;
194	unsigned long timeout = jiffies + msecs_to_jiffies(MDIO_TIMEOUT);
195	u32 reg;
196
197	while (time_after(timeout, jiffies)) {
198		reg = __raw_readl(&regs->user[0].access);
199		if ((reg & USERACCESS_GO) == 0)
200			return 0;
201
202		reg = __raw_readl(&regs->control);
203		if ((reg & CONTROL_IDLE) == 0) {
204			usleep_range(100, 200);
205			continue;
206		}
207
208		/*
209		 * An emac soft_reset may have clobbered the mdio controller's
210		 * state machine.  We need to reset and retry the current
211		 * operation
212		 */
213		dev_warn(data->dev, "resetting idled controller\n");
214		davinci_mdio_enable(data);
215		return -EAGAIN;
216	}
217
218	reg = __raw_readl(&regs->user[0].access);
219	if ((reg & USERACCESS_GO) == 0)
220		return 0;
221
222	dev_err(data->dev, "timed out waiting for user access\n");
223	return -ETIMEDOUT;
224}
225
226/* wait until hardware state machine is idle */
227static inline int wait_for_idle(struct davinci_mdio_data *data)
228{
229	struct davinci_mdio_regs __iomem *regs = data->regs;
230	unsigned long timeout = jiffies + msecs_to_jiffies(MDIO_TIMEOUT);
231
232	while (time_after(timeout, jiffies)) {
233		if (__raw_readl(&regs->control) & CONTROL_IDLE)
234			return 0;
235	}
236	dev_err(data->dev, "timed out waiting for idle\n");
237	return -ETIMEDOUT;
238}
239
240static int davinci_mdio_read(struct mii_bus *bus, int phy_id, int phy_reg)
241{
242	struct davinci_mdio_data *data = bus->priv;
243	u32 reg;
244	int ret;
245
246	if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)
247		return -EINVAL;
248
249	ret = pm_runtime_get_sync(data->dev);
250	if (ret < 0) {
251		pm_runtime_put_noidle(data->dev);
252		return ret;
253	}
254
255	reg = (USERACCESS_GO | USERACCESS_READ | (phy_reg << 21) |
256	       (phy_id << 16));
257
258	while (1) {
259		ret = wait_for_user_access(data);
260		if (ret == -EAGAIN)
261			continue;
262		if (ret < 0)
263			break;
264
265		__raw_writel(reg, &data->regs->user[0].access);
266
267		ret = wait_for_user_access(data);
268		if (ret == -EAGAIN)
269			continue;
270		if (ret < 0)
271			break;
272
273		reg = __raw_readl(&data->regs->user[0].access);
274		ret = (reg & USERACCESS_ACK) ? (reg & USERACCESS_DATA) : -EIO;
275		break;
276	}
277
278	pm_runtime_mark_last_busy(data->dev);
279	pm_runtime_put_autosuspend(data->dev);
280	return ret;
281}
282
283static int davinci_mdio_write(struct mii_bus *bus, int phy_id,
284			      int phy_reg, u16 phy_data)
285{
286	struct davinci_mdio_data *data = bus->priv;
287	u32 reg;
288	int ret;
289
290	if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)
291		return -EINVAL;
292
293	ret = pm_runtime_get_sync(data->dev);
294	if (ret < 0) {
295		pm_runtime_put_noidle(data->dev);
296		return ret;
297	}
298
299	reg = (USERACCESS_GO | USERACCESS_WRITE | (phy_reg << 21) |
300		   (phy_id << 16) | (phy_data & USERACCESS_DATA));
301
302	while (1) {
303		ret = wait_for_user_access(data);
304		if (ret == -EAGAIN)
305			continue;
306		if (ret < 0)
307			break;
308
309		__raw_writel(reg, &data->regs->user[0].access);
310
311		ret = wait_for_user_access(data);
312		if (ret == -EAGAIN)
313			continue;
314		break;
315	}
316
317	pm_runtime_mark_last_busy(data->dev);
318	pm_runtime_put_autosuspend(data->dev);
319
320	return ret;
321}
322
323#if IS_ENABLED(CONFIG_OF)
324static int davinci_mdio_probe_dt(struct mdio_platform_data *data,
325			 struct platform_device *pdev)
326{
327	struct device_node *node = pdev->dev.of_node;
328	u32 prop;
329
330	if (!node)
331		return -EINVAL;
332
333	if (of_property_read_u32(node, "bus_freq", &prop)) {
334		dev_err(&pdev->dev, "Missing bus_freq property in the DT.\n");
335		return -EINVAL;
336	}
337	data->bus_freq = prop;
338
339	return 0;
340}
341#endif
342
343#if IS_ENABLED(CONFIG_OF)
344static const struct davinci_mdio_of_param of_cpsw_mdio_data = {
345	.autosuspend_delay_ms = 100,
346};
347
348static const struct of_device_id davinci_mdio_of_mtable[] = {
349	{ .compatible = "ti,davinci_mdio", },
350	{ .compatible = "ti,cpsw-mdio", .data = &of_cpsw_mdio_data},
351	{ /* sentinel */ },
352};
353MODULE_DEVICE_TABLE(of, davinci_mdio_of_mtable);
354#endif
355
356static int davinci_mdio_probe(struct platform_device *pdev)
357{
358	struct mdio_platform_data *pdata = dev_get_platdata(&pdev->dev);
359	struct device *dev = &pdev->dev;
360	struct davinci_mdio_data *data;
361	struct resource *res;
362	struct phy_device *phy;
363	int ret, addr;
364	int autosuspend_delay_ms = -1;
365
366	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
367	if (!data)
368		return -ENOMEM;
369
370	data->bus = devm_mdiobus_alloc(dev);
371	if (!data->bus) {
372		dev_err(dev, "failed to alloc mii bus\n");
373		return -ENOMEM;
374	}
375
376	if (dev->of_node) {
377		const struct of_device_id	*of_id;
378
379		ret = davinci_mdio_probe_dt(&data->pdata, pdev);
380		if (ret)
381			return ret;
382		snprintf(data->bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
383
384		of_id = of_match_device(davinci_mdio_of_mtable, &pdev->dev);
385		if (of_id) {
386			const struct davinci_mdio_of_param *of_mdio_data;
387
388			of_mdio_data = of_id->data;
389			if (of_mdio_data)
390				autosuspend_delay_ms =
391					of_mdio_data->autosuspend_delay_ms;
392		}
393	} else {
394		data->pdata = pdata ? (*pdata) : default_pdata;
395		snprintf(data->bus->id, MII_BUS_ID_SIZE, "%s-%x",
396			 pdev->name, pdev->id);
397	}
398
399	data->bus->name		= dev_name(dev);
400	data->bus->read		= davinci_mdio_read,
401	data->bus->write	= davinci_mdio_write,
402	data->bus->reset	= davinci_mdio_reset,
403	data->bus->parent	= dev;
404	data->bus->priv		= data;
405
406	data->clk = devm_clk_get(dev, "fck");
407	if (IS_ERR(data->clk)) {
408		dev_err(dev, "failed to get device clock\n");
409		return PTR_ERR(data->clk);
410	}
411
412	dev_set_drvdata(dev, data);
413	data->dev = dev;
414
415	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
416	data->regs = devm_ioremap_resource(dev, res);
417	if (IS_ERR(data->regs))
418		return PTR_ERR(data->regs);
 
 
419
420	davinci_mdio_init_clk(data);
421
422	pm_runtime_set_autosuspend_delay(&pdev->dev, autosuspend_delay_ms);
423	pm_runtime_use_autosuspend(&pdev->dev);
424	pm_runtime_enable(&pdev->dev);
425
426	/* register the mii bus
427	 * Create PHYs from DT only in case if PHY child nodes are explicitly
428	 * defined to support backward compatibility with DTs which assume that
429	 * Davinci MDIO will always scan the bus for PHYs detection.
430	 */
431	if (dev->of_node && of_get_child_count(dev->of_node)) {
432		data->skip_scan = true;
433		ret = of_mdiobus_register(data->bus, dev->of_node);
434	} else {
435		ret = mdiobus_register(data->bus);
436	}
437	if (ret)
438		goto bail_out;
439
440	/* scan and dump the bus */
441	for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
442		phy = mdiobus_get_phy(data->bus, addr);
443		if (phy) {
444			dev_info(dev, "phy[%d]: device %s, driver %s\n",
445				 phy->mdio.addr, phydev_name(phy),
446				 phy->drv ? phy->drv->name : "unknown");
447		}
448	}
449
450	return 0;
451
452bail_out:
453	pm_runtime_dont_use_autosuspend(&pdev->dev);
454	pm_runtime_disable(&pdev->dev);
455	return ret;
456}
457
458static int davinci_mdio_remove(struct platform_device *pdev)
459{
460	struct davinci_mdio_data *data = platform_get_drvdata(pdev);
461
462	if (data->bus)
463		mdiobus_unregister(data->bus);
464
465	pm_runtime_dont_use_autosuspend(&pdev->dev);
466	pm_runtime_disable(&pdev->dev);
467
468	return 0;
469}
470
471#ifdef CONFIG_PM
472static int davinci_mdio_runtime_suspend(struct device *dev)
473{
474	struct davinci_mdio_data *data = dev_get_drvdata(dev);
475	u32 ctrl;
476
477	/* shutdown the scan state machine */
478	ctrl = __raw_readl(&data->regs->control);
479	ctrl &= ~CONTROL_ENABLE;
480	__raw_writel(ctrl, &data->regs->control);
481	wait_for_idle(data);
482
483	return 0;
484}
485
486static int davinci_mdio_runtime_resume(struct device *dev)
487{
488	struct davinci_mdio_data *data = dev_get_drvdata(dev);
489
490	davinci_mdio_enable(data);
491	return 0;
492}
493#endif
494
495#ifdef CONFIG_PM_SLEEP
496static int davinci_mdio_suspend(struct device *dev)
497{
498	struct davinci_mdio_data *data = dev_get_drvdata(dev);
499	int ret = 0;
500
501	data->active_in_suspend = !pm_runtime_status_suspended(dev);
502	if (data->active_in_suspend)
503		ret = pm_runtime_force_suspend(dev);
504	if (ret < 0)
505		return ret;
506
507	/* Select sleep pin state */
508	pinctrl_pm_select_sleep_state(dev);
509
510	return 0;
511}
512
513static int davinci_mdio_resume(struct device *dev)
514{
515	struct davinci_mdio_data *data = dev_get_drvdata(dev);
516
517	/* Select default pin state */
518	pinctrl_pm_select_default_state(dev);
519
520	if (data->active_in_suspend)
521		pm_runtime_force_resume(dev);
522
523	return 0;
524}
525#endif
526
527static const struct dev_pm_ops davinci_mdio_pm_ops = {
528	SET_RUNTIME_PM_OPS(davinci_mdio_runtime_suspend,
529			   davinci_mdio_runtime_resume, NULL)
530	SET_LATE_SYSTEM_SLEEP_PM_OPS(davinci_mdio_suspend, davinci_mdio_resume)
531};
532
533static struct platform_driver davinci_mdio_driver = {
534	.driver = {
535		.name	 = "davinci_mdio",
536		.pm	 = &davinci_mdio_pm_ops,
537		.of_match_table = of_match_ptr(davinci_mdio_of_mtable),
538	},
539	.probe = davinci_mdio_probe,
540	.remove = davinci_mdio_remove,
541};
542
543static int __init davinci_mdio_init(void)
544{
545	return platform_driver_register(&davinci_mdio_driver);
546}
547device_initcall(davinci_mdio_init);
548
549static void __exit davinci_mdio_exit(void)
550{
551	platform_driver_unregister(&davinci_mdio_driver);
552}
553module_exit(davinci_mdio_exit);
554
555MODULE_LICENSE("GPL");
556MODULE_DESCRIPTION("DaVinci MDIO driver");
v5.9
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * DaVinci MDIO Module driver
  4 *
  5 * Copyright (C) 2010 Texas Instruments.
  6 *
  7 * Shamelessly ripped out of davinci_emac.c, original copyrights follow:
  8 *
  9 * Copyright (C) 2009 Texas Instruments.
 10 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 11 */
 12#include <linux/module.h>
 13#include <linux/kernel.h>
 14#include <linux/platform_device.h>
 15#include <linux/delay.h>
 16#include <linux/sched.h>
 17#include <linux/slab.h>
 18#include <linux/phy.h>
 19#include <linux/clk.h>
 20#include <linux/err.h>
 21#include <linux/io.h>
 22#include <linux/iopoll.h>
 23#include <linux/pm_runtime.h>
 24#include <linux/davinci_emac.h>
 25#include <linux/of.h>
 26#include <linux/of_device.h>
 27#include <linux/of_mdio.h>
 28#include <linux/pinctrl/consumer.h>
 29
 30/*
 31 * This timeout definition is a worst-case ultra defensive measure against
 32 * unexpected controller lock ups.  Ideally, we should never ever hit this
 33 * scenario in practice.
 34 */
 35#define MDIO_TIMEOUT		100 /* msecs */
 36
 37#define PHY_REG_MASK		0x1f
 38#define PHY_ID_MASK		0x1f
 39
 40#define DEF_OUT_FREQ		2200000		/* 2.2 MHz */
 41
 42struct davinci_mdio_of_param {
 43	int autosuspend_delay_ms;
 44};
 45
 46struct davinci_mdio_regs {
 47	u32	version;
 48	u32	control;
 49#define CONTROL_IDLE		BIT(31)
 50#define CONTROL_ENABLE		BIT(30)
 51#define CONTROL_MAX_DIV		(0xffff)
 52
 53	u32	alive;
 54	u32	link;
 55	u32	linkintraw;
 56	u32	linkintmasked;
 57	u32	__reserved_0[2];
 58	u32	userintraw;
 59	u32	userintmasked;
 60	u32	userintmaskset;
 61	u32	userintmaskclr;
 62	u32	__reserved_1[20];
 63
 64	struct {
 65		u32	access;
 66#define USERACCESS_GO		BIT(31)
 67#define USERACCESS_WRITE	BIT(30)
 68#define USERACCESS_ACK		BIT(29)
 69#define USERACCESS_READ		(0)
 70#define USERACCESS_DATA		(0xffff)
 71
 72		u32	physel;
 73	}	user[0];
 74};
 75
 76static const struct mdio_platform_data default_pdata = {
 77	.bus_freq = DEF_OUT_FREQ,
 78};
 79
 80struct davinci_mdio_data {
 81	struct mdio_platform_data pdata;
 82	struct davinci_mdio_regs __iomem *regs;
 83	struct clk	*clk;
 84	struct device	*dev;
 85	struct mii_bus	*bus;
 86	bool            active_in_suspend;
 87	unsigned long	access_time; /* jiffies */
 88	/* Indicates that driver shouldn't modify phy_mask in case
 89	 * if MDIO bus is registered from DT.
 90	 */
 91	bool		skip_scan;
 92	u32		clk_div;
 93};
 94
 95static void davinci_mdio_init_clk(struct davinci_mdio_data *data)
 96{
 97	u32 mdio_in, div, mdio_out_khz, access_time;
 98
 99	mdio_in = clk_get_rate(data->clk);
100	div = (mdio_in / data->pdata.bus_freq) - 1;
101	if (div > CONTROL_MAX_DIV)
102		div = CONTROL_MAX_DIV;
103
104	data->clk_div = div;
105	/*
106	 * One mdio transaction consists of:
107	 *	32 bits of preamble
108	 *	32 bits of transferred data
109	 *	24 bits of bus yield (not needed unless shared?)
110	 */
111	mdio_out_khz = mdio_in / (1000 * (div + 1));
112	access_time  = (88 * 1000) / mdio_out_khz;
113
114	/*
115	 * In the worst case, we could be kicking off a user-access immediately
116	 * after the mdio bus scan state-machine triggered its own read.  If
117	 * so, our request could get deferred by one access cycle.  We
118	 * defensively allow for 4 access cycles.
119	 */
120	data->access_time = usecs_to_jiffies(access_time * 4);
121	if (!data->access_time)
122		data->access_time = 1;
123}
124
125static void davinci_mdio_enable(struct davinci_mdio_data *data)
126{
127	/* set enable and clock divider */
128	writel(data->clk_div | CONTROL_ENABLE, &data->regs->control);
129}
130
131static int davinci_mdio_reset(struct mii_bus *bus)
132{
133	struct davinci_mdio_data *data = bus->priv;
134	u32 phy_mask, ver;
135	int ret;
136
137	ret = pm_runtime_get_sync(data->dev);
138	if (ret < 0) {
139		pm_runtime_put_noidle(data->dev);
140		return ret;
141	}
142
143	/* wait for scan logic to settle */
144	msleep(PHY_MAX_ADDR * data->access_time);
145
146	/* dump hardware version info */
147	ver = readl(&data->regs->version);
148	dev_info(data->dev,
149		 "davinci mdio revision %d.%d, bus freq %ld\n",
150		 (ver >> 8) & 0xff, ver & 0xff,
151		 data->pdata.bus_freq);
152
153	if (data->skip_scan)
154		goto done;
155
156	/* get phy mask from the alive register */
157	phy_mask = readl(&data->regs->alive);
158	if (phy_mask) {
159		/* restrict mdio bus to live phys only */
160		dev_info(data->dev, "detected phy mask %x\n", ~phy_mask);
161		phy_mask = ~phy_mask;
162	} else {
163		/* desperately scan all phys */
164		dev_warn(data->dev, "no live phy, scanning all\n");
165		phy_mask = 0;
166	}
167	data->bus->phy_mask = phy_mask;
168
169done:
170	pm_runtime_mark_last_busy(data->dev);
171	pm_runtime_put_autosuspend(data->dev);
172
173	return 0;
174}
175
176/* wait until hardware is ready for another user access */
177static inline int wait_for_user_access(struct davinci_mdio_data *data)
178{
179	struct davinci_mdio_regs __iomem *regs = data->regs;
180	unsigned long timeout = jiffies + msecs_to_jiffies(MDIO_TIMEOUT);
181	u32 reg;
182
183	while (time_after(timeout, jiffies)) {
184		reg = readl(&regs->user[0].access);
185		if ((reg & USERACCESS_GO) == 0)
186			return 0;
187
188		reg = readl(&regs->control);
189		if ((reg & CONTROL_IDLE) == 0) {
190			usleep_range(100, 200);
191			continue;
192		}
193
194		/*
195		 * An emac soft_reset may have clobbered the mdio controller's
196		 * state machine.  We need to reset and retry the current
197		 * operation
198		 */
199		dev_warn(data->dev, "resetting idled controller\n");
200		davinci_mdio_enable(data);
201		return -EAGAIN;
202	}
203
204	reg = readl(&regs->user[0].access);
205	if ((reg & USERACCESS_GO) == 0)
206		return 0;
207
208	dev_err(data->dev, "timed out waiting for user access\n");
209	return -ETIMEDOUT;
210}
211
212/* wait until hardware state machine is idle */
213static inline int wait_for_idle(struct davinci_mdio_data *data)
214{
215	struct davinci_mdio_regs __iomem *regs = data->regs;
216	u32 val, ret;
217
218	ret = readl_poll_timeout(&regs->control, val, val & CONTROL_IDLE,
219				 0, MDIO_TIMEOUT * 1000);
220	if (ret)
221		dev_err(data->dev, "timed out waiting for idle\n");
222
223	return ret;
224}
225
226static int davinci_mdio_read(struct mii_bus *bus, int phy_id, int phy_reg)
227{
228	struct davinci_mdio_data *data = bus->priv;
229	u32 reg;
230	int ret;
231
232	if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)
233		return -EINVAL;
234
235	ret = pm_runtime_get_sync(data->dev);
236	if (ret < 0) {
237		pm_runtime_put_noidle(data->dev);
238		return ret;
239	}
240
241	reg = (USERACCESS_GO | USERACCESS_READ | (phy_reg << 21) |
242	       (phy_id << 16));
243
244	while (1) {
245		ret = wait_for_user_access(data);
246		if (ret == -EAGAIN)
247			continue;
248		if (ret < 0)
249			break;
250
251		writel(reg, &data->regs->user[0].access);
252
253		ret = wait_for_user_access(data);
254		if (ret == -EAGAIN)
255			continue;
256		if (ret < 0)
257			break;
258
259		reg = readl(&data->regs->user[0].access);
260		ret = (reg & USERACCESS_ACK) ? (reg & USERACCESS_DATA) : -EIO;
261		break;
262	}
263
264	pm_runtime_mark_last_busy(data->dev);
265	pm_runtime_put_autosuspend(data->dev);
266	return ret;
267}
268
269static int davinci_mdio_write(struct mii_bus *bus, int phy_id,
270			      int phy_reg, u16 phy_data)
271{
272	struct davinci_mdio_data *data = bus->priv;
273	u32 reg;
274	int ret;
275
276	if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)
277		return -EINVAL;
278
279	ret = pm_runtime_get_sync(data->dev);
280	if (ret < 0) {
281		pm_runtime_put_noidle(data->dev);
282		return ret;
283	}
284
285	reg = (USERACCESS_GO | USERACCESS_WRITE | (phy_reg << 21) |
286		   (phy_id << 16) | (phy_data & USERACCESS_DATA));
287
288	while (1) {
289		ret = wait_for_user_access(data);
290		if (ret == -EAGAIN)
291			continue;
292		if (ret < 0)
293			break;
294
295		writel(reg, &data->regs->user[0].access);
296
297		ret = wait_for_user_access(data);
298		if (ret == -EAGAIN)
299			continue;
300		break;
301	}
302
303	pm_runtime_mark_last_busy(data->dev);
304	pm_runtime_put_autosuspend(data->dev);
305
306	return ret;
307}
308
 
309static int davinci_mdio_probe_dt(struct mdio_platform_data *data,
310			 struct platform_device *pdev)
311{
312	struct device_node *node = pdev->dev.of_node;
313	u32 prop;
314
315	if (!node)
316		return -EINVAL;
317
318	if (of_property_read_u32(node, "bus_freq", &prop)) {
319		dev_err(&pdev->dev, "Missing bus_freq property in the DT.\n");
320		return -EINVAL;
321	}
322	data->bus_freq = prop;
323
324	return 0;
325}
 
326
327#if IS_ENABLED(CONFIG_OF)
328static const struct davinci_mdio_of_param of_cpsw_mdio_data = {
329	.autosuspend_delay_ms = 100,
330};
331
332static const struct of_device_id davinci_mdio_of_mtable[] = {
333	{ .compatible = "ti,davinci_mdio", },
334	{ .compatible = "ti,cpsw-mdio", .data = &of_cpsw_mdio_data},
335	{ /* sentinel */ },
336};
337MODULE_DEVICE_TABLE(of, davinci_mdio_of_mtable);
338#endif
339
340static int davinci_mdio_probe(struct platform_device *pdev)
341{
342	struct mdio_platform_data *pdata = dev_get_platdata(&pdev->dev);
343	struct device *dev = &pdev->dev;
344	struct davinci_mdio_data *data;
345	struct resource *res;
346	struct phy_device *phy;
347	int ret, addr;
348	int autosuspend_delay_ms = -1;
349
350	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
351	if (!data)
352		return -ENOMEM;
353
354	data->bus = devm_mdiobus_alloc(dev);
355	if (!data->bus) {
356		dev_err(dev, "failed to alloc mii bus\n");
357		return -ENOMEM;
358	}
359
360	if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
361		const struct of_device_id	*of_id;
362
363		ret = davinci_mdio_probe_dt(&data->pdata, pdev);
364		if (ret)
365			return ret;
366		snprintf(data->bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
367
368		of_id = of_match_device(davinci_mdio_of_mtable, &pdev->dev);
369		if (of_id) {
370			const struct davinci_mdio_of_param *of_mdio_data;
371
372			of_mdio_data = of_id->data;
373			if (of_mdio_data)
374				autosuspend_delay_ms =
375					of_mdio_data->autosuspend_delay_ms;
376		}
377	} else {
378		data->pdata = pdata ? (*pdata) : default_pdata;
379		snprintf(data->bus->id, MII_BUS_ID_SIZE, "%s-%x",
380			 pdev->name, pdev->id);
381	}
382
383	data->bus->name		= dev_name(dev);
384	data->bus->read		= davinci_mdio_read,
385	data->bus->write	= davinci_mdio_write,
386	data->bus->reset	= davinci_mdio_reset,
387	data->bus->parent	= dev;
388	data->bus->priv		= data;
389
390	data->clk = devm_clk_get(dev, "fck");
391	if (IS_ERR(data->clk)) {
392		dev_err(dev, "failed to get device clock\n");
393		return PTR_ERR(data->clk);
394	}
395
396	dev_set_drvdata(dev, data);
397	data->dev = dev;
398
399	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
400	if (!res)
401		return -EINVAL;
402	data->regs = devm_ioremap(dev, res->start, resource_size(res));
403	if (!data->regs)
404		return -ENOMEM;
405
406	davinci_mdio_init_clk(data);
407
408	pm_runtime_set_autosuspend_delay(&pdev->dev, autosuspend_delay_ms);
409	pm_runtime_use_autosuspend(&pdev->dev);
410	pm_runtime_enable(&pdev->dev);
411
412	/* register the mii bus
413	 * Create PHYs from DT only in case if PHY child nodes are explicitly
414	 * defined to support backward compatibility with DTs which assume that
415	 * Davinci MDIO will always scan the bus for PHYs detection.
416	 */
417	if (dev->of_node && of_get_child_count(dev->of_node))
418		data->skip_scan = true;
419
420	ret = of_mdiobus_register(data->bus, dev->of_node);
 
 
421	if (ret)
422		goto bail_out;
423
424	/* scan and dump the bus */
425	for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
426		phy = mdiobus_get_phy(data->bus, addr);
427		if (phy) {
428			dev_info(dev, "phy[%d]: device %s, driver %s\n",
429				 phy->mdio.addr, phydev_name(phy),
430				 phy->drv ? phy->drv->name : "unknown");
431		}
432	}
433
434	return 0;
435
436bail_out:
437	pm_runtime_dont_use_autosuspend(&pdev->dev);
438	pm_runtime_disable(&pdev->dev);
439	return ret;
440}
441
442static int davinci_mdio_remove(struct platform_device *pdev)
443{
444	struct davinci_mdio_data *data = platform_get_drvdata(pdev);
445
446	if (data->bus)
447		mdiobus_unregister(data->bus);
448
449	pm_runtime_dont_use_autosuspend(&pdev->dev);
450	pm_runtime_disable(&pdev->dev);
451
452	return 0;
453}
454
455#ifdef CONFIG_PM
456static int davinci_mdio_runtime_suspend(struct device *dev)
457{
458	struct davinci_mdio_data *data = dev_get_drvdata(dev);
459	u32 ctrl;
460
461	/* shutdown the scan state machine */
462	ctrl = readl(&data->regs->control);
463	ctrl &= ~CONTROL_ENABLE;
464	writel(ctrl, &data->regs->control);
465	wait_for_idle(data);
466
467	return 0;
468}
469
470static int davinci_mdio_runtime_resume(struct device *dev)
471{
472	struct davinci_mdio_data *data = dev_get_drvdata(dev);
473
474	davinci_mdio_enable(data);
475	return 0;
476}
477#endif
478
479#ifdef CONFIG_PM_SLEEP
480static int davinci_mdio_suspend(struct device *dev)
481{
482	struct davinci_mdio_data *data = dev_get_drvdata(dev);
483	int ret = 0;
484
485	data->active_in_suspend = !pm_runtime_status_suspended(dev);
486	if (data->active_in_suspend)
487		ret = pm_runtime_force_suspend(dev);
488	if (ret < 0)
489		return ret;
490
491	/* Select sleep pin state */
492	pinctrl_pm_select_sleep_state(dev);
493
494	return 0;
495}
496
497static int davinci_mdio_resume(struct device *dev)
498{
499	struct davinci_mdio_data *data = dev_get_drvdata(dev);
500
501	/* Select default pin state */
502	pinctrl_pm_select_default_state(dev);
503
504	if (data->active_in_suspend)
505		pm_runtime_force_resume(dev);
506
507	return 0;
508}
509#endif
510
511static const struct dev_pm_ops davinci_mdio_pm_ops = {
512	SET_RUNTIME_PM_OPS(davinci_mdio_runtime_suspend,
513			   davinci_mdio_runtime_resume, NULL)
514	SET_LATE_SYSTEM_SLEEP_PM_OPS(davinci_mdio_suspend, davinci_mdio_resume)
515};
516
517static struct platform_driver davinci_mdio_driver = {
518	.driver = {
519		.name	 = "davinci_mdio",
520		.pm	 = &davinci_mdio_pm_ops,
521		.of_match_table = of_match_ptr(davinci_mdio_of_mtable),
522	},
523	.probe = davinci_mdio_probe,
524	.remove = davinci_mdio_remove,
525};
526
527static int __init davinci_mdio_init(void)
528{
529	return platform_driver_register(&davinci_mdio_driver);
530}
531device_initcall(davinci_mdio_init);
532
533static void __exit davinci_mdio_exit(void)
534{
535	platform_driver_unregister(&davinci_mdio_driver);
536}
537module_exit(davinci_mdio_exit);
538
539MODULE_LICENSE("GPL");
540MODULE_DESCRIPTION("DaVinci MDIO driver");