Ensures a stable PME (Power Management Event) pin state by disabling PME
on system start and enabling it on shutdown only if WoL (Wake-on-LAN) is
configured. This is needed to avoid issues with some PMICs (Power
Management ICs).
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
---
drivers/net/dsa/microchip/ksz9477.c | 46 ++++++++++++++++++++++++++
drivers/net/dsa/microchip/ksz9477.h | 1 +
drivers/net/dsa/microchip/ksz_common.c | 8 ++++-
drivers/net/dsa/microchip/ksz_common.h | 1 +
4 files changed, 55 insertions(+), 1 deletion(-)
diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c
index bcc8863951ca..d893dfd68815 100644
--- a/drivers/net/dsa/microchip/ksz9477.c
+++ b/drivers/net/dsa/microchip/ksz9477.c
@@ -200,6 +200,46 @@ int ksz9477_set_wol(struct ksz_device *dev, int port,
return 0;
}
+/**
+ * ksz9477_wol_pre_shutdown - Prepares the switch device for shutdown while
+ * considering Wake-on-LAN (WoL) settings.
+ * @dev: The switch device structure.
+ * @wol_enabled: Pointer to a boolean which will be set to true if WoL is
+ * enabled on any port.
+ *
+ * This function prepares the switch device for a safe shutdown while taking
+ * into account the Wake-on-LAN (WoL) settings on the user ports. It updates
+ * the wol_enabled flag accordingly to reflect whether WoL is active on any
+ * port.
+ */
+void ksz9477_wol_pre_shutdown(struct ksz_device *dev, bool *wol_enabled)
+{
+ struct dsa_port *dp;
+ int ret;
+
+ *wol_enabled = false;
+
+ if (!dev->wakeup_source)
+ return;
+
+ dsa_switch_for_each_user_port(dp, dev->ds) {
+ u8 pme_ctrl = 0;
+
+ ret = ksz_pread8(dev, dp->index, REG_PORT_PME_CTRL, &pme_ctrl);
+ if (!ret && pme_ctrl)
+ *wol_enabled = true;
+
+ /* make sure there are no pending wake events which would
+ * prevent the device from going to sleep/shutdown.
+ */
+ ksz9477_handle_wake_reason(dev, dp->index);
+ }
+
+ /* Now we are save to enable PME pin. */
+ if (*wol_enabled)
+ ksz_write8(dev, REG_SW_PME_CTRL, PME_ENABLE);
+}
+
static int ksz9477_wait_vlan_ctrl_ready(struct ksz_device *dev)
{
unsigned int val;
@@ -1280,6 +1320,12 @@ int ksz9477_setup(struct dsa_switch *ds)
/* enable global MIB counter freeze function */
ksz_cfg(dev, REG_SW_MAC_CTRL_6, SW_MIB_COUNTER_FREEZE, true);
+ /* Make sure PME (WoL) is not enabled. If requested, it will be
+ * enabled by ksz9477_wol_pre_shutdown(). Otherwise, some PMICs do not
+ * like PME events changes before shutdown.
+ */
+ ksz_write8(dev, REG_SW_PME_CTRL, 0);
+
return 0;
}
diff --git a/drivers/net/dsa/microchip/ksz9477.h b/drivers/net/dsa/microchip/ksz9477.h
index fa8d0318b437..9e6f1e4b57b7 100644
--- a/drivers/net/dsa/microchip/ksz9477.h
+++ b/drivers/net/dsa/microchip/ksz9477.h
@@ -62,6 +62,7 @@ void ksz9477_get_wol(struct ksz_device *dev, int port,
struct ethtool_wolinfo *wol);
int ksz9477_set_wol(struct ksz_device *dev, int port,
struct ethtool_wolinfo *wol);
+void ksz9477_wol_pre_shutdown(struct ksz_device *dev, bool *wol_is_on);
int ksz9477_port_acl_init(struct ksz_device *dev, int port);
void ksz9477_port_acl_free(struct ksz_device *dev, int port);
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 08556b1dc452..6945ea4febd0 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -321,6 +321,7 @@ static const struct ksz_dev_ops ksz9477_dev_ops = {
.phylink_mac_link_up = ksz9477_phylink_mac_link_up,
.get_wol = ksz9477_get_wol,
.set_wol = ksz9477_set_wol,
+ .wol_pre_shutdown = ksz9477_wol_pre_shutdown,
.config_cpu_port = ksz9477_config_cpu_port,
.tc_cbs_set_cinc = ksz9477_tc_cbs_set_cinc,
.enable_stp_addr = ksz9477_enable_stp_addr,
@@ -3822,7 +3823,12 @@ EXPORT_SYMBOL(ksz_switch_alloc);
*/
void ksz_switch_shutdown(struct ksz_device *dev)
{
- if (dev->dev_ops->reset)
+ bool wol_enabled = false;
+
+ if (dev->dev_ops->wol_pre_shutdown)
+ dev->dev_ops->wol_pre_shutdown(dev, &wol_enabled);
+
+ if (dev->dev_ops->reset && !wol_enabled)
dev->dev_ops->reset(dev);
dsa_switch_shutdown(dev->ds);
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 34a8e9784cca..41917de15ba3 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -378,6 +378,7 @@ struct ksz_dev_ops {
struct ethtool_wolinfo *wol);
int (*set_wol)(struct ksz_device *dev, int port,
struct ethtool_wolinfo *wol);
+ void (*wol_pre_shutdown)(struct ksz_device *dev, bool *wol_enabled);
void (*config_cpu_port)(struct dsa_switch *ds);
int (*enable_stp_addr)(struct ksz_device *dev);
int (*reset)(struct ksz_device *dev);
--
2.39.2
