[PATCH net-next v8 0/5] net: dsa: microchip: provide Wake on LAN support (part 2)

[PATCH net-next v8 0/5] net: dsa: microchip: provide Wake on LAN support (part 2)

[Oleksij Rempel]

This patch series introduces extensive Wake on LAN (WoL) support for the
Microchip KSZ9477 family of switches, coupled with some code refactoring
and error handling enhancements. The principal aim is to enable and
manage Wake on Magic Packet and other PHY event triggers for waking up
the system, whilst ensuring that the switch isn't reset during a
shutdown if WoL is active.

The Wake on LAN functionality is optional and is particularly beneficial
if the PME pins are connected to the SoC as a wake source or to a PMIC
that can enable or wake the SoC.

changes v8:
- rebase on top of net-next and s/slave/user/

changes v7:
- move wakeup-source after reset-gpios
- update "Wake event on port.." debug message
- add and use ksz_is_port_mac_global_usable() instead of
  ksz_switch_macaddr_get/put.

changes v6:
- add variables magic_switched_off and magic_switched_on for readability
- EXPORT_SYMBOL(ksz_switch_shutdown); to fix build as module 

changes v5:
- rework Wake on Magic Packet support.
- Make sure we show more or less realistic information on get_wol by
  comparing refcounted mac address against the ports address
- fix mac address refcounting on set_wol()
- rework shutdown sequence by to handle PMIC related issues. Make sure
  PME pin is net frequently toggled.
- use wakeup_source variable instead of reading PME pin register.

changes v4:
- add ksz_switch_shutdown() and do not skip dsa_switch_shutdown() and
  etc.
- try to configure MAC address on WAKE_MAGIC. If not possible, prevent
  WAKE_MAGIC configuration
- use ksz_switch_macaddr_get() for WAKE_MAGIC.
- prevent ksz_port_set_mac_address if WAKE_MAGIC is active
- do some more refactoring and patch reordering

changes v3:
- use ethernet address of DSA master instead from devicetree
- use dev_ops->wol* instead of list of supported switch
- don't shutdown the switch if WoL is enabled
- rework on top of latest HSR changes

changes v2:
- rebase against latest next

Oleksij Rempel (5):
  net: dsa: microchip: ksz9477: Add Wake on Magic Packet support
  net: dsa: microchip: Refactor comment for ksz_switch_macaddr_get()
    function
  net: dsa: microchip: Add error handling for ksz_switch_macaddr_get()
  net: dsa: microchip: Refactor switch shutdown routine for WoL
    preparation
  net: dsa: microchip: Ensure Stable PME Pin State for Wake-on-LAN

 drivers/net/dsa/microchip/ksz9477.c     | 103 ++++++++++++++++++++++-
 drivers/net/dsa/microchip/ksz9477.h     |   1 +
 drivers/net/dsa/microchip/ksz9477_i2c.c |   5 +-
 drivers/net/dsa/microchip/ksz_common.c  | 104 +++++++++++++++++++++---
 drivers/net/dsa/microchip/ksz_common.h  |   6 ++
 drivers/net/dsa/microchip/ksz_spi.c     |   5 +-
 6 files changed, 200 insertions(+), 24 deletions(-)

-- 
2.39.2

[PATCH net-next v8 1/5] net: dsa: microchip: ksz9477: Add Wake on Magic Packet support

[Oleksij Rempel]

Introduce Wake on Magic Packet (WoL) functionality to the ksz9477
driver.

Major changes include:

1. Extending the `ksz9477_handle_wake_reason` function to identify Magic
   Packet wake events alongside existing wake reasons.

2. Updating the `ksz9477_get_wol` and `ksz9477_set_wol` functions to
   handle WAKE_MAGIC alongside the existing WAKE_PHY option, and to
   program the switch's MAC address register accordingly when Magic
   Packet wake-up is enabled. This change will prevent WAKE_MAGIC
   activation if the related port has a different MAC address compared
   to a MAC address already used by HSR or an already active WAKE_MAGIC
   on another port.

3. Adding a restriction in `ksz_port_set_mac_address` to prevent MAC
   address changes on ports with active Wake on Magic Packet, as the
   switch's MAC address register is utilized for this feature.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
---
 drivers/net/dsa/microchip/ksz9477.c    | 57 ++++++++++++++++++++++++--
 drivers/net/dsa/microchip/ksz_common.c | 43 +++++++++++++++++--
 drivers/net/dsa/microchip/ksz_common.h |  4 ++
 3 files changed, 97 insertions(+), 7 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c
index 2534c3d122e4..441b4597ef27 100644
--- a/drivers/net/dsa/microchip/ksz9477.c
+++ b/drivers/net/dsa/microchip/ksz9477.c
@@ -81,7 +81,8 @@ static int ksz9477_handle_wake_reason(struct ksz_device *dev, int port)
 	if (!pme_status)
 		return 0;
 
-	dev_dbg(dev->dev, "Wake event on port %d due to:%s%s\n", port,
+	dev_dbg(dev->dev, "Wake event on port %d due to:%s%s%s\n", port,
+		pme_status & PME_WOL_MAGICPKT ? " \"Magic Packet\"" : "",
 		pme_status & PME_WOL_LINKUP ? " \"Link Up\"" : "",
 		pme_status & PME_WOL_ENERGY ? " \"Enery detect\"" : "");
 
@@ -109,10 +110,19 @@ void ksz9477_get_wol(struct ksz_device *dev, int port,
 
 	wol->supported = WAKE_PHY;
 
+	/* Check if the current MAC address on this port can be set
+	 * as global for WAKE_MAGIC support. The result may vary
+	 * dynamically based on other ports configurations.
+	 */
+	if (ksz_is_port_mac_global_usable(dev->ds, port))
+		wol->supported |= WAKE_MAGIC;
+
 	ret = ksz_pread8(dev, port, REG_PORT_PME_CTRL, &pme_ctrl);
 	if (ret)
 		return;
 
+	if (pme_ctrl & PME_WOL_MAGICPKT)
+		wol->wolopts |= WAKE_MAGIC;
 	if (pme_ctrl & (PME_WOL_LINKUP | PME_WOL_ENERGY))
 		wol->wolopts |= WAKE_PHY;
 }
@@ -134,10 +144,12 @@ void ksz9477_get_wol(struct ksz_device *dev, int port,
 int ksz9477_set_wol(struct ksz_device *dev, int port,
 		    struct ethtool_wolinfo *wol)
 {
-	u8 pme_ctrl = 0;
+	u8 pme_ctrl = 0, pme_ctrl_old = 0;
+	bool magic_switched_off;
+	bool magic_switched_on;
 	int ret;
 
-	if (wol->wolopts & ~WAKE_PHY)
+	if (wol->wolopts & ~(WAKE_PHY | WAKE_MAGIC))
 		return -EINVAL;
 
 	if (!dev->wakeup_source)
@@ -147,10 +159,42 @@ int ksz9477_set_wol(struct ksz_device *dev, int port,
 	if (ret)
 		return ret;
 
+	if (wol->wolopts & WAKE_MAGIC)
+		pme_ctrl |= PME_WOL_MAGICPKT;
 	if (wol->wolopts & WAKE_PHY)
 		pme_ctrl |= PME_WOL_LINKUP | PME_WOL_ENERGY;
 
-	return ksz_pwrite8(dev, port, REG_PORT_PME_CTRL, pme_ctrl);
+	ret = ksz_pread8(dev, port, REG_PORT_PME_CTRL, &pme_ctrl_old);
+	if (ret)
+		return ret;
+
+	if (pme_ctrl_old == pme_ctrl)
+		return 0;
+
+	magic_switched_off = (pme_ctrl_old & PME_WOL_MAGICPKT) &&
+			    !(pme_ctrl & PME_WOL_MAGICPKT);
+	magic_switched_on = !(pme_ctrl_old & PME_WOL_MAGICPKT) &&
+			    (pme_ctrl & PME_WOL_MAGICPKT);
+
+	/* To keep reference count of MAC address, we should do this
+	 * operation only on change of WOL settings.
+	 */
+	if (magic_switched_on) {
+		ret = ksz_switch_macaddr_get(dev->ds, port, NULL);
+		if (ret)
+			return ret;
+	} else if (magic_switched_off) {
+		ksz_switch_macaddr_put(dev->ds);
+	}
+
+	ret = ksz_pwrite8(dev, port, REG_PORT_PME_CTRL, pme_ctrl);
+	if (ret) {
+		if (magic_switched_on)
+			ksz_switch_macaddr_put(dev->ds);
+		return ret;
+	}
+
+	return 0;
 }
 
 static int ksz9477_wait_vlan_ctrl_ready(struct ksz_device *dev)
@@ -1106,6 +1150,11 @@ void ksz9477_port_setup(struct ksz_device *dev, int port, bool cpu_port)
 
 	/* clear pending wake flags */
 	ksz9477_handle_wake_reason(dev, port);
+
+	/* Disable all WoL options by default. Otherwise
+	 * ksz_switch_macaddr_get/put logic will not work properly.
+	 */
+	ksz_pwrite8(dev, port, REG_PORT_PME_CTRL, 0);
 }
 
 void ksz9477_config_cpu_port(struct dsa_switch *ds)
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index de788f424a3f..8244204e177d 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -3569,6 +3569,7 @@ static int ksz_port_set_mac_address(struct dsa_switch *ds, int port,
 				    const unsigned char *addr)
 {
 	struct dsa_port *dp = dsa_to_port(ds, port);
+	struct ethtool_wolinfo wol;
 
 	if (dp->hsr_dev) {
 		dev_err(ds->dev,
@@ -3577,9 +3578,45 @@ static int ksz_port_set_mac_address(struct dsa_switch *ds, int port,
 		return -EBUSY;
 	}
 
+	ksz_get_wol(ds, dp->index, &wol);
+	if (wol.wolopts & WAKE_MAGIC) {
+		dev_err(ds->dev,
+			"Cannot change MAC address on port %d with active Wake on Magic Packet\n",
+			port);
+		return -EBUSY;
+	}
+
 	return 0;
 }
 
+/**
+ * ksz_is_port_mac_global_usable - Check if the MAC address on a given port
+ *                                 can be used as a global address.
+ * @ds: Pointer to the DSA switch structure.
+ * @port: The port number on which the MAC address is to be checked.
+ *
+ * This function examines the MAC address set on the specified port and
+ * determines if it can be used as a global address for the switch.
+ *
+ * Return: true if the port's MAC address can be used as a global address, false
+ * otherwise.
+ */
+bool ksz_is_port_mac_global_usable(struct dsa_switch *ds, int port)
+{
+	struct net_device *user = dsa_to_port(ds, port)->user;
+	const unsigned char *addr = user->dev_addr;
+	struct ksz_switch_macaddr *switch_macaddr;
+	struct ksz_device *dev = ds->priv;
+
+	ASSERT_RTNL();
+
+	switch_macaddr = dev->switch_macaddr;
+	if (switch_macaddr && !ether_addr_equal(switch_macaddr->addr, addr))
+		return false;
+
+	return true;
+}
+
 /* Program the switch's MAC address register with the MAC address of the
  * requesting user port. This single address is used by the switch for multiple
  * features, like HSR self-address filtering and WoL. Other user ports are
@@ -3587,8 +3624,8 @@ static int ksz_port_set_mac_address(struct dsa_switch *ds, int port,
  * the same. The user ports' MAC addresses must not change while they have
  * ownership of the switch MAC address.
  */
-static int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
-				  struct netlink_ext_ack *extack)
+int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
+			   struct netlink_ext_ack *extack)
 {
 	struct net_device *user = dsa_to_port(ds, port)->user;
 	const unsigned char *addr = user->dev_addr;
@@ -3628,7 +3665,7 @@ static int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
 	return 0;
 }
 
-static void ksz_switch_macaddr_put(struct dsa_switch *ds)
+void ksz_switch_macaddr_put(struct dsa_switch *ds)
 {
 	struct ksz_switch_macaddr *switch_macaddr;
 	struct ksz_device *dev = ds->priv;
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index a7394175fcf6..06996813f9a8 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -390,12 +390,16 @@ int ksz_switch_register(struct ksz_device *dev);
 void ksz_switch_remove(struct ksz_device *dev);
 
 void ksz_init_mib_timer(struct ksz_device *dev);
+bool ksz_is_port_mac_global_usable(struct dsa_switch *ds, int port);
 void ksz_r_mib_stats64(struct ksz_device *dev, int port);
 void ksz88xx_r_mib_stats64(struct ksz_device *dev, int port);
 void ksz_port_stp_state_set(struct dsa_switch *ds, int port, u8 state);
 bool ksz_get_gbit(struct ksz_device *dev, int port);
 phy_interface_t ksz_get_xmii(struct ksz_device *dev, int port, bool gbit);
 extern const struct ksz_chip_data ksz_switch_chips[];
+int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
+			   struct netlink_ext_ack *extack);
+void ksz_switch_macaddr_put(struct dsa_switch *ds);
 
 /* Common register access functions */
 static inline struct regmap *ksz_regmap_8(struct ksz_device *dev)
-- 
2.39.2

Re: [PATCH net-next v8 1/5] net: dsa: microchip: ksz9477: Add Wake on Magic Packet support

[Vladimir Oltean]

On Thu, Oct 26, 2023 at 07:10:47AM +0200, Oleksij Rempel wrote:
> Introduce Wake on Magic Packet (WoL) functionality to the ksz9477
> driver.
> 
> Major changes include:
> 
> 1. Extending the `ksz9477_handle_wake_reason` function to identify Magic
>    Packet wake events alongside existing wake reasons.
> 
> 2. Updating the `ksz9477_get_wol` and `ksz9477_set_wol` functions to
>    handle WAKE_MAGIC alongside the existing WAKE_PHY option, and to
>    program the switch's MAC address register accordingly when Magic
>    Packet wake-up is enabled. This change will prevent WAKE_MAGIC
>    activation if the related port has a different MAC address compared
>    to a MAC address already used by HSR or an already active WAKE_MAGIC
>    on another port.
> 
> 3. Adding a restriction in `ksz_port_set_mac_address` to prevent MAC
>    address changes on ports with active Wake on Magic Packet, as the
>    switch's MAC address register is utilized for this feature.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
> ---

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>

[PATCH net-next v8 2/5] net: dsa: microchip: Refactor comment for ksz_switch_macaddr_get() function

[Oleksij Rempel]

Update the comment to follow kernel-doc format.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/dsa/microchip/ksz_common.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 8244204e177d..0c3adc389d0b 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -3617,12 +3617,20 @@ bool ksz_is_port_mac_global_usable(struct dsa_switch *ds, int port)
 	return true;
 }
 
-/* Program the switch's MAC address register with the MAC address of the
- * requesting user port. This single address is used by the switch for multiple
- * features, like HSR self-address filtering and WoL. Other user ports are
- * allowed to share ownership of this address as long as their MAC address is
- * the same. The user ports' MAC addresses must not change while they have
- * ownership of the switch MAC address.
+/**
+ * ksz_switch_macaddr_get - Program the switch's MAC address register.
+ * @ds: DSA switch instance.
+ * @port: Port number.
+ * @extack: Netlink extended acknowledgment.
+ *
+ * This function programs the switch's MAC address register with the MAC address
+ * of the requesting user port. This single address is used by the switch for
+ * multiple features like HSR self-address filtering and WoL. Other user ports
+ * can share ownership of this address as long as their MAC address is the same.
+ * The MAC addresses of user ports must not change while they have ownership of
+ * the switch MAC address.
+ *
+ * Return: 0 on success, or other error codes on failure.
  */
 int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
 			   struct netlink_ext_ack *extack)
-- 
2.39.2

[PATCH net-next v8 3/5] net: dsa: microchip: Add error handling for ksz_switch_macaddr_get()

[Oleksij Rempel]

Enhance the ksz_switch_macaddr_get() function to handle errors that may
occur during the call to ksz_write8(). Specifically, this update checks
the return value of ksz_write8(), which may fail if regmap ranges
validation is not passed and returns the error code.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
---
 drivers/net/dsa/microchip/ksz_common.c | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 0c3adc389d0b..00be812bef40 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -3640,7 +3640,7 @@ int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
 	struct ksz_switch_macaddr *switch_macaddr;
 	struct ksz_device *dev = ds->priv;
 	const u16 *regs = dev->info->regs;
-	int i;
+	int i, ret;
 
 	/* Make sure concurrent MAC address changes are blocked */
 	ASSERT_RTNL();
@@ -3667,10 +3667,20 @@ int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
 	dev->switch_macaddr = switch_macaddr;
 
 	/* Program the switch MAC address to hardware */
-	for (i = 0; i < ETH_ALEN; i++)
-		ksz_write8(dev, regs[REG_SW_MAC_ADDR] + i, addr[i]);
+	for (i = 0; i < ETH_ALEN; i++) {
+		ret = ksz_write8(dev, regs[REG_SW_MAC_ADDR] + i, addr[i]);
+		if (ret)
+			goto macaddr_drop;
+	}
 
 	return 0;
+
+macaddr_drop:
+	dev->switch_macaddr = NULL;
+	refcount_set(&switch_macaddr->refcount, 0);
+	kfree(switch_macaddr);
+
+	return ret;
 }
 
 void ksz_switch_macaddr_put(struct dsa_switch *ds)
-- 
2.39.2

Re: [PATCH net-next v8 3/5] net: dsa: microchip: Add error handling for ksz_switch_macaddr_get()

[Vladimir Oltean]

On Thu, Oct 26, 2023 at 07:10:49AM +0200, Oleksij Rempel wrote:
> Enhance the ksz_switch_macaddr_get() function to handle errors that may
> occur during the call to ksz_write8(). Specifically, this update checks
> the return value of ksz_write8(), which may fail if regmap ranges
> validation is not passed and returns the error code.
> 
> Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
> Reviewed-by: Andrew Lunn <andrew@lunn.ch>
> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
> ---

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>

>  drivers/net/dsa/microchip/ksz_common.c | 16 +++++++++++++---
>  1 file changed, 13 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
> index 0c3adc389d0b..00be812bef40 100644
> --- a/drivers/net/dsa/microchip/ksz_common.c
> +++ b/drivers/net/dsa/microchip/ksz_common.c
> @@ -3640,7 +3640,7 @@ int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
>  	struct ksz_switch_macaddr *switch_macaddr;
>  	struct ksz_device *dev = ds->priv;
>  	const u16 *regs = dev->info->regs;
> -	int i;
> +	int i, ret;
>  
>  	/* Make sure concurrent MAC address changes are blocked */
>  	ASSERT_RTNL();
> @@ -3667,10 +3667,20 @@ int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
>  	dev->switch_macaddr = switch_macaddr;
>  
>  	/* Program the switch MAC address to hardware */
> -	for (i = 0; i < ETH_ALEN; i++)
> -		ksz_write8(dev, regs[REG_SW_MAC_ADDR] + i, addr[i]);
> +	for (i = 0; i < ETH_ALEN; i++) {
> +		ret = ksz_write8(dev, regs[REG_SW_MAC_ADDR] + i, addr[i]);
> +		if (ret)
> +			goto macaddr_drop;
> +	}
>  
>  	return 0;
> +
> +macaddr_drop:
> +	dev->switch_macaddr = NULL;
> +	refcount_set(&switch_macaddr->refcount, 0);

Nitpick: this line doesn't do any harm, but it doesn't do any good, either.
It can be removed in a follow-up patch.

> +	kfree(switch_macaddr);
> +
> +	return ret;
>  }
>  
>  void ksz_switch_macaddr_put(struct dsa_switch *ds)
> -- 
> 2.39.2
> 

[PATCH net-next v8 4/5] net: dsa: microchip: Refactor switch shutdown routine for WoL preparation

[Oleksij Rempel]

Centralize the switch shutdown routine in a dedicated function,
ksz_switch_shutdown(), to enhance code maintainability and reduce
redundancy. This change abstracts the common shutdown operations
previously duplicated in ksz9477_i2c_shutdown() and ksz_spi_shutdown().

This refactoring is a preparatory step for an upcoming patch to avoid
reset on shutdown if Wake-on-LAN (WoL) is enabled.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 drivers/net/dsa/microchip/ksz9477_i2c.c |  5 +----
 drivers/net/dsa/microchip/ksz_common.c  | 19 +++++++++++++++++++
 drivers/net/dsa/microchip/ksz_common.h  |  1 +
 drivers/net/dsa/microchip/ksz_spi.c     |  5 +----
 4 files changed, 22 insertions(+), 8 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz9477_i2c.c b/drivers/net/dsa/microchip/ksz9477_i2c.c
index 2710afad4f3a..cac4a607e54a 100644
--- a/drivers/net/dsa/microchip/ksz9477_i2c.c
+++ b/drivers/net/dsa/microchip/ksz9477_i2c.c
@@ -66,10 +66,7 @@ static void ksz9477_i2c_shutdown(struct i2c_client *i2c)
 	if (!dev)
 		return;
 
-	if (dev->dev_ops->reset)
-		dev->dev_ops->reset(dev);
-
-	dsa_switch_shutdown(dev->ds);
+	ksz_switch_shutdown(dev);
 
 	i2c_set_clientdata(i2c, NULL);
 }
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index 00be812bef40..3b48e42148a0 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -3845,6 +3845,25 @@ struct ksz_device *ksz_switch_alloc(struct device *base, void *priv)
 }
 EXPORT_SYMBOL(ksz_switch_alloc);
 
+/**
+ * ksz_switch_shutdown - Shutdown routine for the switch device.
+ * @dev: The switch device structure.
+ *
+ * This function is responsible for initiating a shutdown sequence for the
+ * switch device. It invokes the reset operation defined in the device
+ * operations, if available, to reset the switch. Subsequently, it calls the
+ * DSA framework's shutdown function to ensure a proper shutdown of the DSA
+ * switch.
+ */
+void ksz_switch_shutdown(struct ksz_device *dev)
+{
+	if (dev->dev_ops->reset)
+		dev->dev_ops->reset(dev);
+
+	dsa_switch_shutdown(dev->ds);
+}
+EXPORT_SYMBOL(ksz_switch_shutdown);
+
 static void ksz_parse_rgmii_delay(struct ksz_device *dev, int port_num,
 				  struct device_node *port_dn)
 {
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 06996813f9a8..14b4828f80a1 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -400,6 +400,7 @@ extern const struct ksz_chip_data ksz_switch_chips[];
 int ksz_switch_macaddr_get(struct dsa_switch *ds, int port,
 			   struct netlink_ext_ack *extack);
 void ksz_switch_macaddr_put(struct dsa_switch *ds);
+void ksz_switch_shutdown(struct ksz_device *dev);
 
 /* Common register access functions */
 static inline struct regmap *ksz_regmap_8(struct ksz_device *dev)
diff --git a/drivers/net/dsa/microchip/ksz_spi.c b/drivers/net/dsa/microchip/ksz_spi.c
index 279338451621..6f6d878e742c 100644
--- a/drivers/net/dsa/microchip/ksz_spi.c
+++ b/drivers/net/dsa/microchip/ksz_spi.c
@@ -114,10 +114,7 @@ static void ksz_spi_shutdown(struct spi_device *spi)
 	if (!dev)
 		return;
 
-	if (dev->dev_ops->reset)
-		dev->dev_ops->reset(dev);
-
-	dsa_switch_shutdown(dev->ds);
+	ksz_switch_shutdown(dev);
 
 	spi_set_drvdata(spi, NULL);
 }
-- 
2.39.2

[PATCH net-next v8 5/5] net: dsa: microchip: Ensure Stable PME Pin State for Wake-on-LAN

[Oleksij Rempel]

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@pengutronix.de>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 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 441b4597ef27..f24181086e16 100644
--- a/drivers/net/dsa/microchip/ksz9477.c
+++ b/drivers/net/dsa/microchip/ksz9477.c
@@ -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;
 }
 
diff --git a/drivers/net/dsa/microchip/ksz9477.h b/drivers/net/dsa/microchip/ksz9477.h
index fa8d0318b437..ce1e656b800b 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_enabled);
 
 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 3b48e42148a0..3fed406fb46a 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,
@@ -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);
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 14b4828f80a1..b7e8a403a132 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

Re: [PATCH net-next v8 0/5] net: dsa: microchip: provide Wake on LAN support (part 2)

[Vladimir Oltean]

On Thu, Oct 26, 2023 at 07:10:46AM +0200, Oleksij Rempel wrote:
> This patch series introduces extensive Wake on LAN (WoL) support for the
> Microchip KSZ9477 family of switches, coupled with some code refactoring
> and error handling enhancements. The principal aim is to enable and
> manage Wake on Magic Packet and other PHY event triggers for waking up
> the system, whilst ensuring that the switch isn't reset during a
> shutdown if WoL is active.
> 
> The Wake on LAN functionality is optional and is particularly beneficial
> if the PME pins are connected to the SoC as a wake source or to a PMIC
> that can enable or wake the SoC.
> 
> changes v8:
> - rebase on top of net-next and s/slave/user/

I am stunned by what happened here. The timeline seems to be:

- On the 23rd of October, you sent a 9-patch series constituting v7.
- On the 25th of October, 4 of those patches were silently merged, as
  follows:

93aa731e6133 Merge branch 'dsa-microchip-WoL-support'
d264f24409b8 net: dsa: microchip: ksz9477: add Wake on LAN support
aed7425d6510 net: dsa: microchip: use wakeup-source DT property to enable PME output
4e1799ae84fc dt-bindings: net: dsa: microchip: add wakeup-source property
02e987f52cf0 net: dsa: microchip: Add missing MAC address register offset for ksz8863

 commit 93aa731e613399f5145166940b20224a8d116920
 Merge: e43e6d9582e0 d264f24409b8
 Author: David S. Miller <davem@davemloft.net>
 Date:   Wed Oct 25 08:47:33 2023 +0100

     Merge branch 'dsa-microchip-WoL-support'

with no further details as usual (cover letter becomes merge commit
message), no patchwork bot notification, nothing.

- Today you are sending the rest of 5 unmerged patches.
- In parallel, Colin Ian King has sent a fixup for a review comment on
  the first 4 patches from v7, which got silently applied without that
  comment being addressed.

So, given the circumstances, I see that you did the right thing. It's
just that I'm starting to understand less and less of what the rules are
supposed to be.

Re: [PATCH net-next v8 0/5] net: dsa: microchip: provide Wake on LAN support (part 2)

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Thu, 26 Oct 2023 07:10:46 +0200 you wrote:
> This patch series introduces extensive Wake on LAN (WoL) support for the
> Microchip KSZ9477 family of switches, coupled with some code refactoring
> and error handling enhancements. The principal aim is to enable and
> manage Wake on Magic Packet and other PHY event triggers for waking up
> the system, whilst ensuring that the switch isn't reset during a
> shutdown if WoL is active.
> 
> [...]

Here is the summary with links:
  - [net-next,v8,1/5] net: dsa: microchip: ksz9477: Add Wake on Magic Packet support
    https://git.kernel.org/netdev/net-next/c/3b454b6390c3
  - [net-next,v8,2/5] net: dsa: microchip: Refactor comment for ksz_switch_macaddr_get() function
    https://git.kernel.org/netdev/net-next/c/78c21fca0b39
  - [net-next,v8,3/5] net: dsa: microchip: Add error handling for ksz_switch_macaddr_get()
    https://git.kernel.org/netdev/net-next/c/818cdb0f4b38
  - [net-next,v8,4/5] net: dsa: microchip: Refactor switch shutdown routine for WoL preparation
    https://git.kernel.org/netdev/net-next/c/77c819cb493a
  - [net-next,v8,5/5] net: dsa: microchip: Ensure Stable PME Pin State for Wake-on-LAN
    https://git.kernel.org/netdev/net-next/c/8afb91acc4a3

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
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