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path: root/drivers/net/dsa/microchip/ksz9477_i2c.c (follow)
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2022-06-24net: dsa: microchip: remove the ksz8/ksz9477_switch_registerArun Ramadoss1-1/+1
This patch delete the ksz8_switch_register and ksz9477_switch_register since both are calling the ksz_switch_register function. Instead the ksz_switch_register is called from the probe function. Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-24net: dsa: microchip: rename shutdown to reset in ksz_dev_opsArun Ramadoss1-2/+2
This patch renames the shutdown to reset in ksz_dev_ops in order to use the reset dev_ops in the ksz_setup. Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-18net: dsa: microchip: perform the compatibility check for dev probedArun Ramadoss1-6/+24
This patch perform the compatibility check for the device after the chip detect is done. It is to prevent the mismatch between the device compatible specified in the device tree and actual device found during the detect. The ksz9477 device doesn't use any .data in the of_device_id. But the ksz8795_spi uses .data for assigning the regmap between 8830 family and 87xx family switch. Changed the regmap assignment based on the chip_id from the .data. Signed-off-by: Arun Ramadoss <arun.ramadoss@microchip.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-19net: dsa: microchip: add ksz8563 to ksz9477 I2C driverAhmad Fatoum1-0/+1
The KSZ9477 SPI driver already has support for the KSZ8563. The same switch chip can also be managed via i2c and we have an KSZ9477 I2C driver, but that one lacks the relevant compatible entry. Add it. DT bindings already describe this compatible. Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-19net: dsa: be compatible with masters which unregister on shutdownVladimir Oltean1-2/+12
Lino reports that on his system with bcmgenet as DSA master and KSZ9897 as a switch, rebooting or shutting down never works properly. What does the bcmgenet driver have special to trigger this, that other DSA masters do not? It has an implementation of ->shutdown which simply calls its ->remove implementation. Otherwise said, it unregisters its network interface on shutdown. This message can be seen in a loop, and it hangs the reboot process there: unregister_netdevice: waiting for eth0 to become free. Usage count = 3 So why 3? A usage count of 1 is normal for a registered network interface, and any virtual interface which links itself as an upper of that will increment it via dev_hold. In the case of DSA, this is the call path: dsa_slave_create -> netdev_upper_dev_link -> __netdev_upper_dev_link -> __netdev_adjacent_dev_insert -> dev_hold So a DSA switch with 3 interfaces will result in a usage count elevated by two, and netdev_wait_allrefs will wait until they have gone away. Other stacked interfaces, like VLAN, watch NETDEV_UNREGISTER events and delete themselves, but DSA cannot just vanish and go poof, at most it can unbind itself from the switch devices, but that must happen strictly earlier compared to when the DSA master unregisters its net_device, so reacting on the NETDEV_UNREGISTER event is way too late. It seems that it is a pretty established pattern to have a driver's ->shutdown hook redirect to its ->remove hook, so the same code is executed regardless of whether the driver is unbound from the device, or the system is just shutting down. As Florian puts it, it is quite a big hammer for bcmgenet to unregister its net_device during shutdown, but having a common code path with the driver unbind helps ensure it is well tested. So DSA, for better or for worse, has to live with that and engage in an arms race of implementing the ->shutdown hook too, from all individual drivers, and do something sane when paired with masters that unregister their net_device there. The only sane thing to do, of course, is to unlink from the master. However, complications arise really quickly. The pattern of redirecting ->shutdown to ->remove is not unique to bcmgenet or even to net_device drivers. In fact, SPI controllers do it too (see dspi_shutdown -> dspi_remove), and presumably, I2C controllers and MDIO controllers do it too (this is something I have not researched too deeply, but even if this is not the case today, it is certainly plausible to happen in the future, and must be taken into consideration). Since DSA switches might be SPI devices, I2C devices, MDIO devices, the insane implication is that for the exact same DSA switch device, we might have both ->shutdown and ->remove getting called. So we need to do something with that insane environment. The pattern I've come up with is "if this, then not that", so if either ->shutdown or ->remove gets called, we set the device's drvdata to NULL, and in the other hook, we check whether the drvdata is NULL and just do nothing. This is probably not necessary for platform devices, just for devices on buses, but I would really insist for consistency among drivers, because when code is copy-pasted, it is not always copy-pasted from the best sources. So depending on whether the DSA switch's ->remove or ->shutdown will get called first, we cannot really guarantee even for the same driver if rebooting will result in the same code path on all platforms. But nonetheless, we need to do something minimally reasonable on ->shutdown too to fix the bug. Of course, the ->remove will do more (a full teardown of the tree, with all data structures freed, and this is why the bug was not caught for so long). The new ->shutdown method is kept separate from dsa_unregister_switch not because we couldn't have unregistered the switch, but simply in the interest of doing something quick and to the point. The big question is: does the DSA switch's ->shutdown get called earlier than the DSA master's ->shutdown? If not, there is still a risk that we might still trigger the WARN_ON in unregister_netdevice that says we are attempting to unregister a net_device which has uppers. That's no good. Although the reference to the master net_device won't physically go away even if DSA's ->shutdown comes afterwards, remember we have a dev_hold on it. The answer to that question lies in this comment above device_link_add: * A side effect of the link creation is re-ordering of dpm_list and the * devices_kset list by moving the consumer device and all devices depending * on it to the ends of these lists (that does not happen to devices that have * not been registered when this function is called). so the fact that DSA uses device_link_add towards its master is not exactly for nothing. device_shutdown() walks devices_kset from the back, so this is our guarantee that DSA's shutdown happens before the master's shutdown. Fixes: 2f1e8ea726e9 ("net: dsa: link interfaces with the DSA master to get rid of lockdep warnings") Link: https://lore.kernel.org/netdev/20210909095324.12978-1-LinoSanfilippo@gmx.de/ Reported-by: Lino Sanfilippo <LinoSanfilippo@gmx.de> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Tested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-10-09net: dsa: microchip: add ksz9563 to ksz9477 I2C driverChristian Eggers1-0/+1
Add support for the KSZ9563 3-Port Gigabit Ethernet Switch to the ksz9477 driver. The KSZ9563 supports both SPI (already in) and I2C. The ksz9563 is already in the device tree binding documentation. Signed-off-by: Christian Eggers <ceggers@arri.de> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-07-01net: dsa: microchip: enable ksz9893 via i2c in the ksz9477 driverHelmut Grohne1-0/+1
The KSZ9893 3-Port Gigabit Ethernet Switch can be controlled via SPI, I²C or MDIO (very limited and not supported by this driver). While there is already a compatible entry for the SPI bus, it was missing for I²C. Signed-off-by: Helmut Grohne <helmut.grohne@intenta.de> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller1-2/+4
Several cases of overlapping changes which were for the most part trivially resolvable. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17net: dsa: microchip: Add shared regmap mutexMarek Vasut1-2/+4
The KSZ driver uses one regmap per register width (8/16/32), each with it's own lock, but accessing the same set of registers. In theory, it is possible to create a race condition between these regmaps, although the underlying bus (SPI or I2C) locking should assure nothing bad will really happen and the accesses would be correct. To make the driver do the right thing, add one single shared mutex for all the regmaps used by the driver instead. This assures that even if some future hardware is on a bus which does not serialize the accesses the same way SPI or I2C does, nothing bad will happen. Note that the status_mutex was unused and only initied, hence it was renamed and repurposed as the regmap mutex. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Andrew Lunn <andrew@lunn.ch> Cc: David S. Miller <davem@davemloft.net> Cc: Florian Fainelli <f.fainelli@gmail.com> Cc: George McCollister <george.mccollister@gmail.com> Cc: Tristram Ha <Tristram.Ha@microchip.com> Cc: Woojung Huh <woojung.huh@microchip.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-06net: dsa: ksz9477: fix platform_no_drv_owner.cocci warningYueHaibing1-1/+0
Remove .owner field if calls are used which set it automatically Generated by: scripts/coccinelle/api/platform_no_drv_owner.cocci Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-12net: dsa: microchip: add ksz9567 to ksz9477 driverGeorge McCollister1-0/+1
Add support for the KSZ9567 7-Port Gigabit Ethernet Switch to the ksz9477 driver. The KSZ9567 supports both SPI and I2C. Oddly the ksz9567 is already in the device tree binding documentation. Signed-off-by: George McCollister <george.mccollister@gmail.com> Reviewed-by: Marek Vasut <marex@denx.de> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-09-12net: dsa: microchip: add KSZ9477 I2C driverTristram Ha1-0/+100
Add KSZ9477 I2C driver support. The code ksz9477.c and ksz_common.c are used together to generate the I2C driver. Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com> [george.mccollister@gmail.com: bring up to date, use ksz_common regmap macros] Signed-off-by: George McCollister <george.mccollister@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>