Commit 8afb91ac authored by Oleksij Rempel's avatar Oleksij Rempel Committed by Jakub Kicinski
Browse files

net: dsa: microchip: Ensure Stable PME Pin State for Wake-on-LAN 



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: default avatarOleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20231026051051.2316937-6-o.rempel@pengutronix.de


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 77c819cb

drivers/net/dsa/microchip/ksz9477.c

+46 −0
Original line number Diff line number Diff line
@@ -197,6 +197,46 @@ 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;
@@ -1277,6 +1317,12 @@ 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;

}

drivers/net/dsa/microchip/ksz9477.h

+1 −0
Original line number Diff line number Diff line
@@ -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_enabled);



int ksz9477_port_acl_init(struct ksz_device *dev, int port);

void ksz9477_port_acl_free(struct ksz_device *dev, int port);

drivers/net/dsa/microchip/ksz_common.c

+7 −1
Original line number Diff line number Diff line
@@ -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,
@@ -3857,7 +3858,12 @@ 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);

drivers/net/dsa/microchip/ksz_common.h

+1 −0
Original line number Diff line number Diff line
@@ -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);