net: dsa: microchip: Add suspend/resume support to KSZ DSA driver

The KSZ DSA driver starts a timer to read MIB counters periodically to
avoid count overrun.  During system suspend this will give an error for
not able to write to register as the SPI system returns an error when
it is in suspend state.  This implementation stops the timer when the
system goes into suspend and restarts it when resumed.

Signed-off-by: Tristram Ha <tristram.ha@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20241218020311.70628-1-Tristram.Ha@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/dsa/microchip/ksz9477_i2c.c b/drivers/net/dsa/microchip/ksz9477_i2c.c
index 1c6d7fc16772373e13726806c96e776750e6ec24..a2beb27459f18cabb222b1b3d44aaedbc25b8856 100644 (file)
--- a/drivers/net/dsa/microchip/ksz9477_i2c.c
+++ b/drivers/net/dsa/microchip/ksz9477_i2c.c
@@ -127,10 +127,14 @@ static const struct of_device_id ksz9477_dt_ids[] = {
 };
 MODULE_DEVICE_TABLE(of, ksz9477_dt_ids);
 
+static DEFINE_SIMPLE_DEV_PM_OPS(ksz_i2c_pm_ops,
+                               ksz_switch_suspend, ksz_switch_resume);
+
 static struct i2c_driver ksz9477_i2c_driver = {
        .driver = {
                .name   = "ksz9477-switch",
                .of_match_table = ksz9477_dt_ids,
+               .pm = &ksz_i2c_pm_ops,
        },
        .probe = ksz9477_i2c_probe,
        .remove = ksz9477_i2c_remove,

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index df314724e6a740623e4ac3eadf8f845a3455f725..a8dac7ff6b817be827b0ce3132780d8312d9ea2a 100644 (file)
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -4586,6 +4586,23 @@ static int ksz_hsr_leave(struct dsa_switch *ds, int port,
        return 0;
 }
 
+static int ksz_suspend(struct dsa_switch *ds)
+{
+       struct ksz_device *dev = ds->priv;
+
+       cancel_delayed_work_sync(&dev->mib_read);
+       return 0;
+}
+
+static int ksz_resume(struct dsa_switch *ds)
+{
+       struct ksz_device *dev = ds->priv;
+
+       if (dev->mib_read_interval)
+               schedule_delayed_work(&dev->mib_read, dev->mib_read_interval);
+       return 0;
+}
+
 static const struct dsa_switch_ops ksz_switch_ops = {
        .get_tag_protocol       = ksz_get_tag_protocol,
        .connect_tag_protocol   = ksz_connect_tag_protocol,
@@ -4626,6 +4643,8 @@ static const struct dsa_switch_ops ksz_switch_ops = {
        .port_max_mtu           = ksz_max_mtu,
        .get_wol                = ksz_get_wol,
        .set_wol                = ksz_set_wol,
+       .suspend                = ksz_suspend,
+       .resume                 = ksz_resume,
        .get_ts_info            = ksz_get_ts_info,
        .port_hwtstamp_get      = ksz_hwtstamp_get,
        .port_hwtstamp_set      = ksz_hwtstamp_set,
@@ -5126,6 +5145,24 @@ void ksz_switch_remove(struct ksz_device *dev)
 }
 EXPORT_SYMBOL(ksz_switch_remove);
 
+#ifdef CONFIG_PM_SLEEP
+int ksz_switch_suspend(struct device *dev)
+{
+       struct ksz_device *priv = dev_get_drvdata(dev);
+
+       return dsa_switch_suspend(priv->ds);
+}
+EXPORT_SYMBOL(ksz_switch_suspend);
+
+int ksz_switch_resume(struct device *dev)
+{
+       struct ksz_device *priv = dev_get_drvdata(dev);
+
+       return dsa_switch_resume(priv->ds);
+}
+EXPORT_SYMBOL(ksz_switch_resume);
+#endif
+
 MODULE_AUTHOR("Woojung Huh <Woojung.Huh@microchip.com>");
 MODULE_DESCRIPTION("Microchip KSZ Series Switch DSA Driver");
 MODULE_LICENSE("GPL");

diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index b3bb75ca0796d208f232455677d338209bdaa97d..2bc96127a447bf203e7514ec96824ddb6ee7b007 100644 (file)
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -444,6 +444,8 @@ struct ksz_dev_ops {
 struct ksz_device *ksz_switch_alloc(struct device *base, void *priv);
 int ksz_switch_register(struct ksz_device *dev);
 void ksz_switch_remove(struct ksz_device *dev);
+int ksz_switch_suspend(struct device *dev);
+int ksz_switch_resume(struct device *dev);
 
 void ksz_init_mib_timer(struct ksz_device *dev);
 bool ksz_is_port_mac_global_usable(struct dsa_switch *ds, int port);

diff --git a/drivers/net/dsa/microchip/ksz_spi.c b/drivers/net/dsa/microchip/ksz_spi.c
index 108a958dc356f10ec5808b6ea4ab22f06614c61b..b633d263098c615dcd916e765879ccf5cd7008cc 100644 (file)
--- a/drivers/net/dsa/microchip/ksz_spi.c
+++ b/drivers/net/dsa/microchip/ksz_spi.c
@@ -239,10 +239,14 @@ static const struct spi_device_id ksz_spi_ids[] = {
 };
 MODULE_DEVICE_TABLE(spi, ksz_spi_ids);
 
+static DEFINE_SIMPLE_DEV_PM_OPS(ksz_spi_pm_ops,
+                               ksz_switch_suspend, ksz_switch_resume);
+
 static struct spi_driver ksz_spi_driver = {
        .driver = {
                .name   = "ksz-switch",
                .of_match_table = ksz_dt_ids,
+               .pm = &ksz_spi_pm_ops,
        },
        .id_table = ksz_spi_ids,
        .probe  = ksz_spi_probe,