1 // SPDX-License-Identifier: GPL-2.0+
2 /* MDIO Bus interface
39 #include <trace/events/mdio.h>
41 #include "mdio-boardinfo.h"
46 	mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev,  in mdiobus_register_gpiod()
48 	if (IS_ERR(mdiodev->reset_gpio))  in mdiobus_register_gpiod()
49 		return PTR_ERR(mdiodev->reset_gpio);  in mdiobus_register_gpiod()
51 	if (mdiodev->reset_gpio)  in mdiobus_register_gpiod()
52 		gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset");  in mdiobus_register_gpiod()
61 	reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy");  in mdiobus_register_reset()
65 	mdiodev->reset_ctrl = reset;  in mdiobus_register_reset()
74 	if (mdiodev->bus->mdio_map[mdiodev->addr])  in mdiobus_register_device()
75 		return -EBUSY;  in mdiobus_register_device()
77 	if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {  in mdiobus_register_device()
90 	mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;  in mdiobus_register_device()
98 	if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)  in mdiobus_unregister_device()
99 		return -EINVAL;  in mdiobus_unregister_device()
101 	reset_control_put(mdiodev->reset_ctrl);  in mdiobus_unregister_device()
103 	mdiodev->bus->mdio_map[mdiodev->addr] = NULL;  in mdiobus_unregister_device()
109 struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)  in mdiobus_get_phy()  argument
113 	if (addr < 0 || addr >= ARRAY_SIZE(bus->mdio_map))  in mdiobus_get_phy()
116 	mdiodev = bus->mdio_map[addr];  in mdiobus_get_phy()
121 	if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))  in mdiobus_get_phy()
124 	return container_of(mdiodev, struct phy_device, mdio);  in mdiobus_get_phy()
128 bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)  in mdiobus_is_registered_device()  argument
130 	return bus->mdio_map[addr];  in mdiobus_is_registered_device()
135  * mdiobus_alloc_size - allocate a mii_bus structure
137  * If non-zero, then bus->priv is points to that memory.
139  * Description: called by a bus driver to allocate an mii_bus
144 	struct mii_bus *bus;  in mdiobus_alloc_size()  local
145 	size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);  in mdiobus_alloc_size()
153 		alloc_size = sizeof(*bus);  in mdiobus_alloc_size()
155 	bus = kzalloc(alloc_size, GFP_KERNEL);  in mdiobus_alloc_size()
156 	if (!bus)  in mdiobus_alloc_size()
159 	bus->state = MDIOBUS_ALLOCATED;  in mdiobus_alloc_size()
161 		bus->priv = (void *)bus + aligned_size;  in mdiobus_alloc_size()
163 	/* Initialise the interrupts to polling and 64-bit seqcounts */  in mdiobus_alloc_size()
165 		bus->irq[i] = PHY_POLL;  in mdiobus_alloc_size()
166 		u64_stats_init(&bus->stats[i].syncp);  in mdiobus_alloc_size()
169 	return bus;  in mdiobus_alloc_size()
174  * mdiobus_release - mii_bus device release callback
182 	struct mii_bus *bus = to_mii_bus(d);  in mdiobus_release()  local
183 	BUG_ON(bus->state != MDIOBUS_RELEASED &&  in mdiobus_release()
185 	       bus->state != MDIOBUS_ALLOCATED);  in mdiobus_release()
186 	kfree(bus);  in mdiobus_release()
201 		start = u64_stats_fetch_begin(&s->syncp);  in mdio_bus_get_stat()
203 	} while (u64_stats_fetch_retry(&s->syncp, start));  in mdio_bus_get_stat()
208 static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset)  in mdio_bus_get_global_stat()  argument
214 		val += mdio_bus_get_stat(&bus->stats[i], offset);  in mdio_bus_get_global_stat()
223 	struct mii_bus *bus = to_mii_bus(dev);  in mdio_bus_stat_field_show()  local
229 	sattr = eattr->var;  in mdio_bus_stat_field_show()
231 	if (sattr->addr < 0)  in mdio_bus_stat_field_show()
232 		val = mdio_bus_get_global_stat(bus, sattr->field_offset);  in mdio_bus_stat_field_show()
234 		val = mdio_bus_get_stat(&bus->stats[sattr->addr],  in mdio_bus_stat_field_show()
235 					sattr->field_offset);  in mdio_bus_stat_field_show()
245 	struct mii_bus *bus = mdiodev->bus;  in mdio_bus_device_stat_field_show()  local
248 	int addr = mdiodev->addr;  in mdio_bus_device_stat_field_show()
252 	sattr = eattr->var;  in mdio_bus_device_stat_field_show()
254 	val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset);  in mdio_bus_device_stat_field_show()
265 		-1, offsetof(struct mdio_bus_stats, field)		\
273 		-1, offsetof(struct mdio_bus_stats, field)		\
401  * mdio_find_bus - Given the name of a mdiobus, find the mii_bus.
406  * and this must be put_deviced'ed once the bus is finished with.
419  * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
424  * and this must be put once the bus is finished with.
443 /* Walk the list of subnodes of a mdio bus and look for a node that
444  * matches the mdio device's address with its 'reg' property. If
445  * found, set the of_node pointer for the mdio device. This allows
446  * auto-probed phy devices to be supplied with information passed in
449 static void of_mdiobus_link_mdiodev(struct mii_bus *bus,  in of_mdiobus_link_mdiodev()  argument
452 	struct device *dev = &mdiodev->dev;  in of_mdiobus_link_mdiodev()
455 	if (dev->of_node || !bus->dev.of_node)  in of_mdiobus_link_mdiodev()
458 	for_each_available_child_of_node(bus->dev.of_node, child) {  in of_mdiobus_link_mdiodev()
465 		if (addr == mdiodev->addr) {  in of_mdiobus_link_mdiodev()
466 			dev->of_node = child;  in of_mdiobus_link_mdiodev()
467 			dev->fwnode = of_fwnode_handle(child);  in of_mdiobus_link_mdiodev()
473 static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,  in of_mdiobus_link_mdiodev()  argument
480  * mdiobus_create_device_from_board_info - create a full MDIO device given
482  * @bus: MDIO bus to create the devices on
487 static int mdiobus_create_device(struct mii_bus *bus,  in mdiobus_create_device()  argument
493 	mdiodev = mdio_device_create(bus, bi->mdio_addr);  in mdiobus_create_device()
495 		return -ENODEV;  in mdiobus_create_device()
497 	strncpy(mdiodev->modalias, bi->modalias,  in mdiobus_create_device()
498 		sizeof(mdiodev->modalias));  in mdiobus_create_device()
499 	mdiodev->bus_match = mdio_device_bus_match;  in mdiobus_create_device()
500 	mdiodev->dev.platform_data = (void *)bi->platform_data;  in mdiobus_create_device()
510  * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
511  * @bus: target mii_bus
512  * @owner: module containing bus accessor functions
514  * Description: Called by a bus driver to bring up all the PHYs
515  *   on a given bus, and attach them to the bus. Drivers should use
517  *   need to pass a specific owner module. MDIO devices which are not
523 int __mdiobus_register(struct mii_bus *bus, struct module *owner)  in __mdiobus_register()  argument
529 	if (NULL == bus || NULL == bus->name ||  in __mdiobus_register()
530 	    NULL == bus->read || NULL == bus->write)  in __mdiobus_register()
531 		return -EINVAL;  in __mdiobus_register()
533 	BUG_ON(bus->state != MDIOBUS_ALLOCATED &&  in __mdiobus_register()
534 	       bus->state != MDIOBUS_UNREGISTERED);  in __mdiobus_register()
536 	bus->owner = owner;  in __mdiobus_register()
537 	bus->dev.parent = bus->parent;  in __mdiobus_register()
538 	bus->dev.class = &mdio_bus_class;  in __mdiobus_register()
539 	bus->dev.groups = NULL;  in __mdiobus_register()
540 	dev_set_name(&bus->dev, "%s", bus->id);  in __mdiobus_register()
547 	bus->state = MDIOBUS_UNREGISTERED;  in __mdiobus_register()
549 	err = device_register(&bus->dev);  in __mdiobus_register()
551 		pr_err("mii_bus %s failed to register\n", bus->id);  in __mdiobus_register()
552 		return -EINVAL;  in __mdiobus_register()
555 	mutex_init(&bus->mdio_lock);  in __mdiobus_register()
556 	mutex_init(&bus->shared_lock);  in __mdiobus_register()
558 	/* de-assert bus level PHY GPIO reset */  in __mdiobus_register()
559 	gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_LOW);  in __mdiobus_register()
561 		dev_err(&bus->dev, "mii_bus %s couldn't get reset GPIO\n",  in __mdiobus_register()
562 			bus->id);  in __mdiobus_register()
563 		device_del(&bus->dev);  in __mdiobus_register()
566 		bus->reset_gpiod = gpiod;  in __mdiobus_register()
569 		fsleep(bus->reset_delay_us);  in __mdiobus_register()
571 		if (bus->reset_post_delay_us > 0)  in __mdiobus_register()
572 			fsleep(bus->reset_post_delay_us);  in __mdiobus_register()
575 	if (bus->reset) {  in __mdiobus_register()
576 		err = bus->reset(bus);  in __mdiobus_register()
582 		if ((bus->phy_mask & BIT(i)) == 0) {  in __mdiobus_register()
585 			phydev = mdiobus_scan(bus, i);  in __mdiobus_register()
586 			if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {  in __mdiobus_register()
593 	mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);  in __mdiobus_register()
595 	bus->state = MDIOBUS_REGISTERED;  in __mdiobus_register()
596 	dev_dbg(&bus->dev, "probed\n");  in __mdiobus_register()
600 	while (--i >= 0) {  in __mdiobus_register()
601 		mdiodev = bus->mdio_map[i];  in __mdiobus_register()
605 		mdiodev->device_remove(mdiodev);  in __mdiobus_register()
606 		mdiodev->device_free(mdiodev);  in __mdiobus_register()
610 	if (bus->reset_gpiod)  in __mdiobus_register()
611 		gpiod_set_value_cansleep(bus->reset_gpiod, 1);  in __mdiobus_register()
613 	device_del(&bus->dev);  in __mdiobus_register()
618 void mdiobus_unregister(struct mii_bus *bus)  in mdiobus_unregister()  argument
623 	if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED))  in mdiobus_unregister()
625 	bus->state = MDIOBUS_UNREGISTERED;  in mdiobus_unregister()
628 		mdiodev = bus->mdio_map[i];  in mdiobus_unregister()
632 		if (mdiodev->reset_gpio)  in mdiobus_unregister()
633 			gpiod_put(mdiodev->reset_gpio);  in mdiobus_unregister()
635 		mdiodev->device_remove(mdiodev);  in mdiobus_unregister()
636 		mdiodev->device_free(mdiodev);  in mdiobus_unregister()
640 	if (bus->reset_gpiod)  in mdiobus_unregister()
641 		gpiod_set_value_cansleep(bus->reset_gpiod, 1);  in mdiobus_unregister()
643 	device_del(&bus->dev);  in mdiobus_unregister()
648  * mdiobus_free - free a struct mii_bus
649  * @bus: mii_bus to free
655 void mdiobus_free(struct mii_bus *bus)  in mdiobus_free()  argument
658 	if (bus->state == MDIOBUS_ALLOCATED) {  in mdiobus_free()
659 		kfree(bus);  in mdiobus_free()
663 	BUG_ON(bus->state != MDIOBUS_UNREGISTERED);  in mdiobus_free()
664 	bus->state = MDIOBUS_RELEASED;  in mdiobus_free()
666 	put_device(&bus->dev);  in mdiobus_free()
671  * mdiobus_scan - scan a bus for MDIO devices.
672  * @bus: mii_bus to scan
673  * @addr: address on bus to scan
675  * This function scans the MDIO bus, looking for devices which can be
677  * MDIO devices have such registers, but PHY devices typically
679  * treated as a PHY. Other MDIO devices, such as switches, will
682 struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)  in mdiobus_scan()  argument
684 	struct phy_device *phydev = ERR_PTR(-ENODEV);  in mdiobus_scan()
687 	switch (bus->probe_capabilities) {  in mdiobus_scan()
690 		phydev = get_phy_device(bus, addr, false);  in mdiobus_scan()
693 		phydev = get_phy_device(bus, addr, true);  in mdiobus_scan()
696 		phydev = get_phy_device(bus, addr, false);  in mdiobus_scan()
698 			phydev = get_phy_device(bus, addr, true);  in mdiobus_scan()
706 	 * For DT, see if the auto-probed phy has a correspoding child  in mdiobus_scan()
707 	 * in the bus node, and set the of_node pointer in this case.  in mdiobus_scan()
709 	of_mdiobus_link_mdiodev(bus, &phydev->mdio);  in mdiobus_scan()
714 		return ERR_PTR(-ENODEV);  in mdiobus_scan()
724 	u64_stats_update_begin(&stats->syncp);  in mdiobus_stats_acct()
726 	u64_stats_inc(&stats->transfers);  in mdiobus_stats_acct()
728 		u64_stats_inc(&stats->errors);  in mdiobus_stats_acct()
733 		u64_stats_inc(&stats->reads);  in mdiobus_stats_acct()
735 		u64_stats_inc(&stats->writes);  in mdiobus_stats_acct()
737 	u64_stats_update_end(&stats->syncp);  in mdiobus_stats_acct()
742  * __mdiobus_read - Unlocked version of the mdiobus_read function
743  * @bus: the mii_bus struct
747  * Read a MDIO bus register. Caller must hold the mdio bus lock.
751 int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)  in __mdiobus_read()  argument
755 	WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));  in __mdiobus_read()
757 	retval = bus->read(bus, addr, regnum);  in __mdiobus_read()
759 	trace_mdio_access(bus, 1, addr, regnum, retval, retval);  in __mdiobus_read()
760 	mdiobus_stats_acct(&bus->stats[addr], true, retval);  in __mdiobus_read()
767  * __mdiobus_write - Unlocked version of the mdiobus_write function
768  * @bus: the mii_bus struct
773  * Write a MDIO bus register. Caller must hold the mdio bus lock.
777 int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)  in __mdiobus_write()  argument
781 	WARN_ON_ONCE(!mutex_is_locked(&bus->mdio_lock));  in __mdiobus_write()
783 	err = bus->write(bus, addr, regnum, val);  in __mdiobus_write()
785 	trace_mdio_access(bus, 0, addr, regnum, val, err);  in __mdiobus_write()
786 	mdiobus_stats_acct(&bus->stats[addr], false, err);  in __mdiobus_write()
793  * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function
794  * @bus: the mii_bus struct
805 int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,  in __mdiobus_modify_changed()  argument
810 	ret = __mdiobus_read(bus, addr, regnum);  in __mdiobus_modify_changed()
818 	ret = __mdiobus_write(bus, addr, regnum, new);  in __mdiobus_modify_changed()
825  * mdiobus_read_nested - Nested version of the mdiobus_read function
826  * @bus: the mii_bus struct
830  * In case of nested MDIO bus access avoid lockdep false positives by
834  * because the bus read/write functions may wait for an interrupt
837 int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)  in mdiobus_read_nested()  argument
841 	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);  in mdiobus_read_nested()
842 	retval = __mdiobus_read(bus, addr, regnum);  in mdiobus_read_nested()
843 	mutex_unlock(&bus->mdio_lock);  in mdiobus_read_nested()
850  * mdiobus_read - Convenience function for reading a given MII mgmt register
851  * @bus: the mii_bus struct
856  * because the bus read/write functions may wait for an interrupt
859 int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)  in mdiobus_read()  argument
863 	mutex_lock(&bus->mdio_lock);  in mdiobus_read()
864 	retval = __mdiobus_read(bus, addr, regnum);  in mdiobus_read()
865 	mutex_unlock(&bus->mdio_lock);  in mdiobus_read()
872  * mdiobus_write_nested - Nested version of the mdiobus_write function
873  * @bus: the mii_bus struct
878  * In case of nested MDIO bus access avoid lockdep false positives by
882  * because the bus read/write functions may wait for an interrupt
885 int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)  in mdiobus_write_nested()  argument
889 	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);  in mdiobus_write_nested()
890 	err = __mdiobus_write(bus, addr, regnum, val);  in mdiobus_write_nested()
891 	mutex_unlock(&bus->mdio_lock);  in mdiobus_write_nested()
898  * mdiobus_write - Convenience function for writing a given MII mgmt register
899  * @bus: the mii_bus struct
905  * because the bus read/write functions may wait for an interrupt
908 int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)  in mdiobus_write()  argument
912 	mutex_lock(&bus->mdio_lock);  in mdiobus_write()
913 	err = __mdiobus_write(bus, addr, regnum, val);  in mdiobus_write()
914 	mutex_unlock(&bus->mdio_lock);  in mdiobus_write()
921  * mdiobus_modify - Convenience function for modifying a given mdio device
923  * @bus: the mii_bus struct
929 int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set)  in mdiobus_modify()  argument
933 	mutex_lock(&bus->mdio_lock);  in mdiobus_modify()
934 	err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);  in mdiobus_modify()
935 	mutex_unlock(&bus->mdio_lock);  in mdiobus_modify()
942  * mdio_bus_match - determine if given MDIO driver supports the given
943  *		    MDIO device
944  * @dev: target MDIO device
945  * @drv: given MDIO driver
947  * Description: Given a MDIO device, and a MDIO driver, return 1 if
950  *   of MDIO devices have different match criteria.
954 	struct mdio_device *mdio = to_mdio_device(dev);  in mdio_bus_match()  local
959 	if (mdio->bus_match)  in mdio_bus_match()
960 		return mdio->bus_match(dev, drv);  in mdio_bus_match()
969 	/* Some devices have extra OF data and an OF-style MODALIAS */  in mdio_uevent()
971 	if (rc != -ENODEV)  in mdio_uevent()
1028 MODULE_DESCRIPTION("MDIO bus/device layer");