Commit 8f3d044b authored by Kory Maincent (Dent Project)'s avatar Kory Maincent (Dent Project) Committed by Jakub Kicinski
Browse files

net: pse-pd: pd692x0: Preserve PSE configuration across reboots 



Detect when PSE hardware is already configured (user byte == 42) and
skip hardware initialization to prevent power interruption to connected
devices during system reboots.

Previously, the driver would always reconfigure the PSE hardware on
probe, causing a port matrix reflash that resulted in temporary power
loss to all connected devices. This change maintains power continuity
by preserving existing configuration when the PSE has been previously
initialized.

Signed-off-by: default avatarKory Maincent <kory.maincent@bootlin.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20251013-feature_pd692x0_reboot_keep_conf-v2-3-68ab082a93dd@bootlin.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 6fa1f8b6

drivers/net/pse-pd/pd692x0.c

+32 −3
Original line number Diff line number Diff line
@@ -30,6 +30,8 @@ 
#define PD692X0_FW_MIN_VER	5

#define PD692X0_FW_PATCH_VER	5



#define PD692X0_USER_BYTE	42



enum pd692x0_fw_state {

	PD692X0_FW_UNKNOWN,

	PD692X0_FW_OK,
@@ -80,6 +82,7 @@ enum { 
	PD692X0_MSG_GET_PORT_PARAM,

	PD692X0_MSG_GET_POWER_BANK,

	PD692X0_MSG_SET_POWER_BANK,

	PD692X0_MSG_SET_USER_BYTE,



	/* add new message above here */

	PD692X0_MSG_CNT
@@ -103,6 +106,7 @@ struct pd692x0_priv { 
	bool last_cmd_key;

	unsigned long last_cmd_key_time;



	bool cfg_saved;

	enum ethtool_c33_pse_admin_state admin_state[PD692X0_MAX_PIS];

	struct regulator_dev *manager_reg[PD692X0_MAX_MANAGERS];

	int manager_pw_budget[PD692X0_MAX_MANAGERS];
@@ -193,6 +197,12 @@ static const struct pd692x0_msg pd692x0_msg_template_list[PD692X0_MSG_CNT] = { 
		.key = PD692X0_KEY_CMD,

		.sub = {0x07, 0x0b, 0x57},

	},

	[PD692X0_MSG_SET_USER_BYTE] = {

		.key = PD692X0_KEY_PRG,

		.sub = {0x41, PD692X0_USER_BYTE},

		.data = {0x4e, 0x4e, 0x4e, 0x4e,

			 0x4e, 0x4e, 0x4e, 0x4e},

	},

};



static u8 pd692x0_build_msg(struct pd692x0_msg *msg, u8 echo)
@@ -1233,6 +1243,15 @@ static void pd692x0_managers_free_pw_budget(struct pd692x0_priv *priv) 
	}

}



static int

pd692x0_save_user_byte(struct pd692x0_priv *priv)

{

	struct pd692x0_msg msg, buf;



	msg = pd692x0_msg_template_list[PD692X0_MSG_SET_USER_BYTE];

	return pd692x0_sendrecv_msg(priv, &msg, &buf);

}



static int pd692x0_setup_pi_matrix(struct pse_controller_dev *pcdev)

{

	struct pd692x0_priv *priv = to_pd692x0_priv(pcdev);
@@ -1268,10 +1287,17 @@ static int pd692x0_setup_pi_matrix(struct pse_controller_dev *pcdev) 
	if (ret)

		goto err_managers_req_pw;



	/* Do not init the conf if it is already saved */

	if (!priv->cfg_saved) {

		ret = pd692x0_hw_conf_init(priv);

		if (ret)

			goto err_managers_req_pw;



		ret = pd692x0_save_user_byte(priv);

		if (ret)

			goto err_managers_req_pw;

	}



	pd692x0_of_put_managers(priv, manager);

	kfree(manager);

	return 0;
@@ -1793,6 +1819,9 @@ static int pd692x0_i2c_probe(struct i2c_client *client) 
		}

	}



	if (buf.data[2] == PD692X0_USER_BYTE)

		priv->cfg_saved = true;



	priv->np = dev->of_node;

	priv->pcdev.nr_lines = PD692X0_MAX_PIS;

	priv->pcdev.owner = THIS_MODULE;