From bcd3d9d9246f35c62c5d652d20569a76dbdf4bd1 Mon Sep 17 00:00:00 2001 From: Miquel Raynal Date: Tue, 5 Feb 2019 12:07:28 +0100 Subject: [PATCH] net: dsa: mv88e6xxx: Prevent suspend to RAM On one hand, the mv88e6xxx driver has a work queue called in loop which will attempt register accesses after MDIO bus suspension, that entirely freezes the platform during suspend. On the other hand, the DSA core is not ready yet to support suspend to RAM operation because so far there is no way to recover reliably the switch configuration. To avoid the kernel to freeze when suspending with a switch driven by the mv88e6xxx driver, we choose to prevent the driver suspension and in the same way, the whole platform. Signed-off-by: Miquel Raynal Reviewed-by: Andrew Lunn Reviewed-by: Vivien Didelot Signed-off-by: David S. Miller --- drivers/net/dsa/mv88e6xxx/chip.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c index 8dca2c949e73..669a7f13fdce 100644 --- a/drivers/net/dsa/mv88e6xxx/chip.c +++ b/drivers/net/dsa/mv88e6xxx/chip.c @@ -4764,6 +4764,21 @@ static const void *pdata_device_get_match_data(struct device *dev) return NULL; } +/* There is no suspend to RAM support at DSA level yet, the switch configuration + * would be lost after a power cycle so prevent it to be suspended. + */ +static int __maybe_unused mv88e6xxx_suspend(struct device *dev) +{ + return -EOPNOTSUPP; +} + +static int __maybe_unused mv88e6xxx_resume(struct device *dev) +{ + return 0; +} + +static SIMPLE_DEV_PM_OPS(mv88e6xxx_pm_ops, mv88e6xxx_suspend, mv88e6xxx_resume); + static int mv88e6xxx_probe(struct mdio_device *mdiodev) { struct dsa_mv88e6xxx_pdata *pdata = mdiodev->dev.platform_data; @@ -4948,6 +4963,7 @@ static struct mdio_driver mv88e6xxx_driver = { .mdiodrv.driver = { .name = "mv88e6085", .of_match_table = mv88e6xxx_of_match, + .pm = &mv88e6xxx_pm_ops, }, }; -- 2.45.2