net: dsa: microchip: add WoL support for KSZ87xx family

Add WoL support for KSZ87xx family of switches. This code was tested
with a KSZ8794 chip.

Implement ksz_common usage of the new device-tree property
'microchip,pme-active-high'.

Make use of the now generalized ksz_common WoL functions, adding an
additional interrupt register write for KSZ87xx. Add helper functions
to convert from PME (port) read/writes to indirect register
read/writes in the dedicated ksz8795 sources.  Add initial
configuration during (port) setup as per KSZ9477.

Signed-off-by: Pieter Van Trappen <pieter.van.trappen@cern.ch>
Acked-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Link: https://patch.msgid.link/20240813142750.772781-5-vtpieter@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 19 insertions, 5 deletions

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index e2a9a652c41a..3f3230d181d8 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -307,6 +307,9 @@ static const struct ksz_dev_ops ksz8_dev_ops = {
 	.init = ksz8_switch_init,
 	.exit = ksz8_switch_exit,
 	.change_mtu = ksz8_change_mtu,
+	.pme_write8 = ksz8_pme_write8,
+	.pme_pread8 = ksz8_pme_pread8,
+	.pme_pwrite8 = ksz8_pme_pwrite8,
 };
 
 static void ksz9477_phylink_mac_link_up(struct phylink_config *config,
@@ -423,6 +426,9 @@ static const u16 ksz8795_regs[] = {
 	[S_MULTICAST_CTRL]		= 0x04,
 	[P_XMII_CTRL_0]			= 0x06,
 	[P_XMII_CTRL_1]			= 0x06,
+	[REG_SW_PME_CTRL]		= 0x8003,
+	[REG_PORT_PME_STATUS]		= 0x8003,
+	[REG_PORT_PME_CTRL]		= 0x8007,
 };
 
 static const u32 ksz8795_masks[] = {
@@ -3800,7 +3806,7 @@ static void ksz_get_wol(struct dsa_switch *ds, int port,
 	u8 pme_ctrl;
 	int ret;
 
-	if (!is_ksz9477(dev))
+	if (!is_ksz9477(dev) && !ksz_is_ksz87xx(dev))
 		return;
 
 	if (!dev->wakeup_source)
@@ -3853,7 +3859,7 @@ static int ksz_set_wol(struct dsa_switch *ds, int port,
 	if (wol->wolopts & ~(WAKE_PHY | WAKE_MAGIC))
 		return -EINVAL;
 
-	if (!is_ksz9477(dev))
+	if (!is_ksz9477(dev) && !ksz_is_ksz87xx(dev))
 		return -EOPNOTSUPP;
 
 	if (!dev->wakeup_source)
@@ -3919,12 +3925,13 @@ static void ksz_wol_pre_shutdown(struct ksz_device *dev, bool *wol_enabled)
 {
 	const struct ksz_dev_ops *ops = dev->dev_ops;
 	const u16 *regs = dev->info->regs;
+	u8 pme_pin_en = PME_ENABLE;
 	struct dsa_port *dp;
 	int ret;
 
 	*wol_enabled = false;
 
-	if (!is_ksz9477(dev))
+	if (!is_ksz9477(dev) && !ksz_is_ksz87xx(dev))
 		return;
 
 	if (!dev->wakeup_source)
@@ -3945,8 +3952,13 @@ static void ksz_wol_pre_shutdown(struct ksz_device *dev, bool *wol_enabled)
 	}
 
 	/* Now we are save to enable PME pin. */
-	if (*wol_enabled)
-		ops->pme_write8(dev, regs[REG_SW_PME_CTRL], PME_ENABLE);
+	if (*wol_enabled) {
+		if (dev->pme_active_high)
+			pme_pin_en |= PME_POLARITY;
+		ops->pme_write8(dev, regs[REG_SW_PME_CTRL], pme_pin_en);
+		if (ksz_is_ksz87xx(dev))
+			ksz_write8(dev, KSZ87XX_REG_INT_EN, KSZ87XX_INT_PME_MASK);
+	}
 }
 
 static int ksz_port_set_mac_address(struct dsa_switch *ds, int port,
@@ -4661,6 +4673,8 @@ int ksz_switch_register(struct ksz_device *dev)
 
 		dev->wakeup_source = of_property_read_bool(dev->dev->of_node,
 							   "wakeup-source");
+		dev->pme_active_high = of_property_read_bool(dev->dev->of_node,
+							     "microchip,pme-active-high");
 	}
 
 	ret = dsa_register_switch(dev->ds);