Subject: [PATCH RFC net-next 01/10] net: pcs: xpcs: move PCS reset to .pcs_pre_config()

From: "Russell King (Oracle)" <[email-masked]>
Date: Mon, 23 Sep 2024 15:00:59 +0100

Move the PCS reset to .pcs_pre_config() rather than at creation time,
which means we call the reset function with the interface that we're
actually going to be using to talk to the downstream device.

Signed-off-by: Russell King (Oracle) <[email-masked]>
---
 drivers/net/pcs/pcs-xpcs.c   | 39 +++++++++++++++++++++++++++---------
 include/linux/pcs/pcs-xpcs.h |  1 +
 2 files changed, 30 insertions(+), 10 deletions(-)

diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c
index 82463f9d50c8..7c6c40ddf722 100644
--- a/drivers/net/pcs/pcs-xpcs.c
+++ b/drivers/net/pcs/pcs-xpcs.c
@@ -659,6 +659,30 @@ int xpcs_config_eee(struct dw_xpcs *xpcs, int mult_fact_100ns, int enable)
 }
 EXPORT_SYMBOL_GPL(xpcs_config_eee);
 
+static void xpcs_pre_config(struct phylink_pcs *pcs, phy_interface_t interface)
+{
+	struct dw_xpcs *xpcs = phylink_pcs_to_xpcs(pcs);
+	const struct dw_xpcs_compat *compat;
+	int ret;
+
+	if (!xpcs->need_reset)
+		return;
+
+	compat = xpcs_find_compat(xpcs->desc, interface);
+	if (!compat) {
+		dev_err(&xpcs->mdiodev->dev, "unsupported interface %s\n",
+			phy_modes(interface));
+		return;
+	}
+
+	ret = xpcs_soft_reset(xpcs, compat);
+	if (ret)
+		dev_err(&xpcs->mdiodev->dev, "soft reset failed: %pe\n",
+			ERR_PTR(ret));
+
+	xpcs->need_reset = false;
+}
+
 static int xpcs_config_aneg_c37_sgmii(struct dw_xpcs *xpcs,
 				      unsigned int neg_mode)
 {
@@ -1365,6 +1389,7 @@ static const struct dw_xpcs_desc xpcs_desc_list[] = {
 
 static const struct phylink_pcs_ops xpcs_phylink_ops = {
 	.pcs_validate = xpcs_validate,
+	.pcs_pre_config = xpcs_pre_config,
 	.pcs_config = xpcs_config,
 	.pcs_get_state = xpcs_get_state,
 	.pcs_an_restart = xpcs_an_restart,
@@ -1460,18 +1485,12 @@ static int xpcs_init_id(struct dw_xpcs *xpcs)
 
 static int xpcs_init_iface(struct dw_xpcs *xpcs, phy_interface_t interface)
 {
-	const struct dw_xpcs_compat *compat;
-
-	compat = xpcs_find_compat(xpcs->desc, interface);
-	if (!compat)
-		return -EINVAL;
-
-	if (xpcs->info.pma == WX_TXGBE_XPCS_PMA_10G_ID) {
+	if (xpcs->info.pma == WX_TXGBE_XPCS_PMA_10G_ID)
 		xpcs->pcs.poll = false;
-		return 0;
-	}
+	else
+		xpcs->need_reset = true;
 
-	return xpcs_soft_reset(xpcs, compat);
+	return 0;
 }
 
 static struct dw_xpcs *xpcs_create(struct mdio_device *mdiodev,
diff --git a/include/linux/pcs/pcs-xpcs.h b/include/linux/pcs/pcs-xpcs.h
index b4a4eb6c8866..fd75d0605bb6 100644
--- a/include/linux/pcs/pcs-xpcs.h
+++ b/include/linux/pcs/pcs-xpcs.h
@@ -61,6 +61,7 @@ struct dw_xpcs {
 	struct clk_bulk_data clks[DW_XPCS_NUM_CLKS];
 	struct phylink_pcs pcs;
 	phy_interface_t interface;
+	bool need_reset;
 };
 
 int xpcs_get_an_mode(struct dw_xpcs *xpcs, phy_interface_t interface);
-- 
2.30.2