[PATCH net-next] net: dsa: mv88e6xxx: Add suspend/resume callbacks

[Miquel Raynal]

Bring S2RAM support to the mv88e6xxx DSA driver.

The content of the *_irq_poll() helper is moved in *_do_irq_poll() so
that that the function can be called from the ->resume() callback
without using the *work pointer.

Signed-off-by: Miquel Raynal <miquel.ray...@bootlin.com>
---
 drivers/net/dsa/mv88e6xxx/chip.c | 52 ++++++++++++++++++++++++++++++--
 1 file changed, 49 insertions(+), 3 deletions(-)

diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index 8a517d8fb9d1..b88efa9b86e0 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -442,15 +442,21 @@ static int mv88e6xxx_g1_irq_setup(struct mv88e6xxx_chip 
*chip)
        return err;
 }
 
+static void mv88e6xxx_do_irq_poll(struct mv88e6xxx_chip *chip)
+{
+       mv88e6xxx_g1_irq_thread_work(chip);
+
+       kthread_queue_delayed_work(chip->kworker, &chip->irq_poll_work,
+                                  msecs_to_jiffies(100));
+}
+
 static void mv88e6xxx_irq_poll(struct kthread_work *work)
 {
        struct mv88e6xxx_chip *chip = container_of(work,
                                                   struct mv88e6xxx_chip,
                                                   irq_poll_work.work);
-       mv88e6xxx_g1_irq_thread_work(chip);
 
-       kthread_queue_delayed_work(chip->kworker, &chip->irq_poll_work,
-                                  msecs_to_jiffies(100));
+       mv88e6xxx_do_irq_poll(chip);
 }
 
 static int mv88e6xxx_irq_poll_setup(struct mv88e6xxx_chip *chip)
@@ -4651,6 +4657,45 @@ static const void *pdata_device_get_match_data(struct 
device *dev)
        return NULL;
 }
 
+static int __maybe_unused mv88e6xxx_suspend(struct device *dev)
+{
+       struct dsa_switch *ds = dev_get_drvdata(dev);
+       struct mv88e6xxx_chip *chip = ds->priv;
+
+       kthread_cancel_delayed_work_sync(&chip->irq_poll_work);
+
+       return dsa_switch_suspend(ds);
+}
+
+static int __maybe_unused mv88e6xxx_resume(struct device *dev)
+{
+       struct dsa_switch *ds = dev_get_drvdata(dev);
+       struct mv88e6xxx_chip *chip = ds->priv;
+       int ret;
+
+       mv88e6xxx_phy_init(chip);
+
+       mutex_lock(&chip->reg_lock);
+       ret = mv88e6xxx_switch_reset(chip);
+       mutex_unlock(&chip->reg_lock);
+       if (ret) {
+               dev_err(dev, "Failed to reset the switch\n");
+               return ret;
+       }
+
+       ret = mv88e6xxx_setup(ds);
+       if (ret) {
+               dev_err(dev, "Failed to setup the switch\n");
+               return ret;
+       }
+
+       mv88e6xxx_do_irq_poll(chip);
+
+       return dsa_switch_resume(ds);
+}
+
+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;
@@ -4835,6 +4880,7 @@ static struct mdio_driver mv88e6xxx_driver = {
        .mdiodrv.driver = {
                .name = "mv88e6085",
                .of_match_table = mv88e6xxx_of_match,
+               .pm = &mv88e6xxx_pm_ops,
        },
 };
 
-- 
2.19.1