net: pse-pd: Split ethtool_get_status into multiple callbacks

The ethtool_get_status callback currently handles all status and PSE
information within a single function. This approach has two key
drawbacks:

1. If the core requires some information for purposes other than
   ethtool_get_status, redundant code will be needed to fetch the same
   data from the driver (like is_enabled).

2. Drivers currently have access to all information passed to ethtool.
   New variables will soon be added to ethtool status, such as PSE ID,
   power domain IDs, and budget evaluation strategies, which are meant
   to be managed solely by the core. Drivers should not have the ability
   to modify these variables.

To resolve these issues, ethtool_get_status has been split into multiple
callbacks, with each handling a specific piece of information required
by ethtool or the core.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

4 files changed, 244 insertions, 78 deletions

diff --git a/drivers/net/pse-pd/pd692x0.c b/drivers/net/pse-pd/pd692x0.c
index 9f00538f7e45..da5d09ed628a 100644
--- a/drivers/net/pse-pd/pd692x0.c
+++ b/drivers/net/pse-pd/pd692x0.c
@@ -517,21 +517,38 @@ pd692x0_pse_ext_state_map[] = {
 	{ /* sentinel */ }
 };
 
-static void
-pd692x0_get_ext_state(struct ethtool_c33_pse_ext_state_info *c33_ext_state_info,
-		      u32 status_code)
+static int
+pd692x0_pi_get_ext_state(struct pse_controller_dev *pcdev, int id,
+			 struct pse_ext_state_info *ext_state_info)
 {
+	struct ethtool_c33_pse_ext_state_info *c33_ext_state_info;
 	const struct pd692x0_pse_ext_state_mapping *ext_state_map;
+	struct pd692x0_priv *priv = to_pd692x0_priv(pcdev);
+	struct pd692x0_msg msg, buf = {0};
+	int ret;
+
+	ret = pd692x0_fw_unavailable(priv);
+	if (ret)
+		return ret;
 
+	msg = pd692x0_msg_template_list[PD692X0_MSG_GET_PORT_STATUS];
+	msg.sub[2] = id;
+	ret = pd692x0_sendrecv_msg(priv, &msg, &buf);
+	if (ret < 0)
+		return ret;
+
+	c33_ext_state_info = &ext_state_info->c33_ext_state_info;
 	ext_state_map = pd692x0_pse_ext_state_map;
 	while (ext_state_map->status_code) {
-		if (ext_state_map->status_code == status_code) {
+		if (ext_state_map->status_code == buf.sub[0]) {
 			c33_ext_state_info->c33_pse_ext_state = ext_state_map->pse_ext_state;
 			c33_ext_state_info->__c33_pse_ext_substate = ext_state_map->pse_ext_substate;
-			return;
+			return  0;
 		}
 		ext_state_map++;
 	}
+
+	return 0;
 }
 
 struct pd692x0_class_pw {
@@ -613,35 +630,36 @@ static int pd692x0_pi_set_pw_from_table(struct device *dev,
 }
 
 static int
-pd692x0_pi_get_pw_ranges(struct pse_control_status *st)
+pd692x0_pi_get_pw_limit_ranges(struct pse_controller_dev *pcdev, int id,
+			       struct pse_pw_limit_ranges *pw_limit_ranges)
 {
+	struct ethtool_c33_pse_pw_limit_range *c33_pw_limit_ranges;
 	const struct pd692x0_class_pw *pw_table;
 	int i;
 
 	pw_table = pd692x0_class_pw_table;
-	st->c33_pw_limit_ranges = kcalloc(PD692X0_CLASS_PW_TABLE_SIZE,
-					  sizeof(struct ethtool_c33_pse_pw_limit_range),
-					  GFP_KERNEL);
-	if (!st->c33_pw_limit_ranges)
+	c33_pw_limit_ranges = kcalloc(PD692X0_CLASS_PW_TABLE_SIZE,
+				      sizeof(*c33_pw_limit_ranges),
+				      GFP_KERNEL);
+	if (!c33_pw_limit_ranges)
 		return -ENOMEM;
 
 	for (i = 0; i < PD692X0_CLASS_PW_TABLE_SIZE; i++, pw_table++) {
-		st->c33_pw_limit_ranges[i].min = pw_table->class_pw;
-		st->c33_pw_limit_ranges[i].max = pw_table->class_pw + pw_table->max_added_class_pw;
+		c33_pw_limit_ranges[i].min = pw_table->class_pw;
+		c33_pw_limit_ranges[i].max = pw_table->class_pw +
+					     pw_table->max_added_class_pw;
 	}
 
-	st->c33_pw_limit_nb_ranges = i;
-	return 0;
+	pw_limit_ranges->c33_pw_limit_ranges = c33_pw_limit_ranges;
+	return i;
 }
 
-static int pd692x0_ethtool_get_status(struct pse_controller_dev *pcdev,
-				      unsigned long id,
-				      struct netlink_ext_ack *extack,
-				      struct pse_control_status *status)
+static int
+pd692x0_pi_get_admin_state(struct pse_controller_dev *pcdev, int id,
+			   struct pse_admin_state *admin_state)
 {
 	struct pd692x0_priv *priv = to_pd692x0_priv(pcdev);
 	struct pd692x0_msg msg, buf = {0};
-	u32 class;
 	int ret;
 
 	ret = pd692x0_fw_unavailable(priv);
@@ -654,39 +672,65 @@ static int pd692x0_ethtool_get_status(struct pse_controller_dev *pcdev,
 	if (ret < 0)
 		return ret;
 
-	/* Compare Port Status (Communication Protocol Document par. 7.1) */
-	if ((buf.sub[0] & 0xf0) == 0x80 || (buf.sub[0] & 0xf0) == 0x90)
-		status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_DELIVERING;
-	else if (buf.sub[0] == 0x1b || buf.sub[0] == 0x22)
-		status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_SEARCHING;
-	else if (buf.sub[0] == 0x12)
-		status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_FAULT;
-	else
-		status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_DISABLED;
-
 	if (buf.sub[1])
-		status->c33_admin_state = ETHTOOL_C33_PSE_ADMIN_STATE_ENABLED;
+		admin_state->c33_admin_state =
+			ETHTOOL_C33_PSE_ADMIN_STATE_ENABLED;
 	else
-		status->c33_admin_state = ETHTOOL_C33_PSE_ADMIN_STATE_DISABLED;
+		admin_state->c33_admin_state =
+			ETHTOOL_C33_PSE_ADMIN_STATE_DISABLED;
 
-	priv->admin_state[id] = status->c33_admin_state;
+	priv->admin_state[id] = admin_state->c33_admin_state;
 
-	pd692x0_get_ext_state(&status->c33_ext_state_info, buf.sub[0]);
-	status->c33_actual_pw = (buf.data[0] << 4 | buf.data[1]) * 100;
+	return 0;
+}
 
-	msg = pd692x0_msg_template_list[PD692X0_MSG_GET_PORT_PARAM];
+static int
+pd692x0_pi_get_pw_status(struct pse_controller_dev *pcdev, int id,
+			 struct pse_pw_status *pw_status)
+{
+	struct pd692x0_priv *priv = to_pd692x0_priv(pcdev);
+	struct pd692x0_msg msg, buf = {0};
+	int ret;
+
+	ret = pd692x0_fw_unavailable(priv);
+	if (ret)
+		return ret;
+
+	msg = pd692x0_msg_template_list[PD692X0_MSG_GET_PORT_STATUS];
 	msg.sub[2] = id;
-	memset(&buf, 0, sizeof(buf));
 	ret = pd692x0_sendrecv_msg(priv, &msg, &buf);
 	if (ret < 0)
 		return ret;
 
-	ret = pd692x0_pi_get_pw_from_table(buf.data[0], buf.data[1]);
-	if (ret < 0)
+	/* Compare Port Status (Communication Protocol Document par. 7.1) */
+	if ((buf.sub[0] & 0xf0) == 0x80 || (buf.sub[0] & 0xf0) == 0x90)
+		pw_status->c33_pw_status =
+			ETHTOOL_C33_PSE_PW_D_STATUS_DELIVERING;
+	else if (buf.sub[0] == 0x1b || buf.sub[0] == 0x22)
+		pw_status->c33_pw_status =
+			ETHTOOL_C33_PSE_PW_D_STATUS_SEARCHING;
+	else if (buf.sub[0] == 0x12)
+		pw_status->c33_pw_status =
+			ETHTOOL_C33_PSE_PW_D_STATUS_FAULT;
+	else
+		pw_status->c33_pw_status =
+			ETHTOOL_C33_PSE_PW_D_STATUS_DISABLED;
+
+	return 0;
+}
+
+static int
+pd692x0_pi_get_pw_class(struct pse_controller_dev *pcdev, int id)
+{
+	struct pd692x0_priv *priv = to_pd692x0_priv(pcdev);
+	struct pd692x0_msg msg, buf = {0};
+	u32 class;
+	int ret;
+
+	ret = pd692x0_fw_unavailable(priv);
+	if (ret)
 		return ret;
-	status->c33_avail_pw_limit = ret;
 
-	memset(&buf, 0, sizeof(buf));
 	msg = pd692x0_msg_template_list[PD692X0_MSG_GET_PORT_CLASS];
 	msg.sub[2] = id;
 	ret = pd692x0_sendrecv_msg(priv, &msg, &buf);
@@ -695,13 +739,29 @@ static int pd692x0_ethtool_get_status(struct pse_controller_dev *pcdev,
 
 	class = buf.data[3] >> 4;
 	if (class <= 8)
-		status->c33_pw_class = class;
+		return class;
+
+	return 0;
+}
+
+static int
+pd692x0_pi_get_actual_pw(struct pse_controller_dev *pcdev, int id)
+{
+	struct pd692x0_priv *priv = to_pd692x0_priv(pcdev);
+	struct pd692x0_msg msg, buf = {0};
+	int ret;
+
+	ret = pd692x0_fw_unavailable(priv);
+	if (ret)
+		return ret;
 
-	ret = pd692x0_pi_get_pw_ranges(status);
+	msg = pd692x0_msg_template_list[PD692X0_MSG_GET_PORT_STATUS];
+	msg.sub[2] = id;
+	ret = pd692x0_sendrecv_msg(priv, &msg, &buf);
 	if (ret < 0)
 		return ret;
 
-	return 0;
+	return (buf.data[0] << 4 | buf.data[1]) * 100;
 }
 
 static struct pd692x0_msg_ver pd692x0_get_sw_version(struct pd692x0_priv *priv)
@@ -1038,13 +1098,18 @@ static int pd692x0_pi_set_pw_limit(struct pse_controller_dev *pcdev,
 
 static const struct pse_controller_ops pd692x0_ops = {
 	.setup_pi_matrix = pd692x0_setup_pi_matrix,
-	.ethtool_get_status = pd692x0_ethtool_get_status,
+	.pi_get_admin_state = pd692x0_pi_get_admin_state,
+	.pi_get_pw_status = pd692x0_pi_get_pw_status,
+	.pi_get_ext_state = pd692x0_pi_get_ext_state,
+	.pi_get_pw_class = pd692x0_pi_get_pw_class,
+	.pi_get_actual_pw = pd692x0_pi_get_actual_pw,
 	.pi_enable = pd692x0_pi_enable,
 	.pi_disable = pd692x0_pi_disable,
 	.pi_is_enabled = pd692x0_pi_is_enabled,
 	.pi_get_voltage = pd692x0_pi_get_voltage,
 	.pi_get_pw_limit = pd692x0_pi_get_pw_limit,
 	.pi_set_pw_limit = pd692x0_pi_set_pw_limit,
+	.pi_get_pw_limit_ranges = pd692x0_pi_get_pw_limit_ranges,
 };
 
 #define PD692X0_FW_LINE_MAX_SZ 0xff
diff --git a/drivers/net/pse-pd/pse_core.c b/drivers/net/pse-pd/pse_core.c
index ae819bfed1b1..5f2a9f36e4ed 100644
--- a/drivers/net/pse-pd/pse_core.c
+++ b/drivers/net/pse-pd/pse_core.c
@@ -443,6 +443,13 @@ int pse_controller_register(struct pse_controller_dev *pcdev)
 	if (!pcdev->nr_lines)
 		pcdev->nr_lines = 1;
 
+	if (!pcdev->ops->pi_get_admin_state ||
+	    !pcdev->ops->pi_get_pw_status) {
+		dev_err(pcdev->dev,
+			"Mandatory status report callbacks are missing");
+		return -EINVAL;
+	}
+
 	ret = of_load_pse_pis(pcdev);
 	if (ret)
 		return ret;
@@ -745,25 +752,81 @@ EXPORT_SYMBOL_GPL(of_pse_control_get);
  */
 int pse_ethtool_get_status(struct pse_control *psec,
 			   struct netlink_ext_ack *extack,
-			   struct pse_control_status *status)
+			   struct ethtool_pse_control_status *status)
 {
+	struct pse_admin_state admin_state = {0};
+	struct pse_pw_status pw_status = {0};
 	const struct pse_controller_ops *ops;
 	struct pse_controller_dev *pcdev;
-	int err;
+	int ret;
 
 	pcdev = psec->pcdev;
 	ops = pcdev->ops;
-	if (!ops->ethtool_get_status) {
-		NL_SET_ERR_MSG(extack,
-			       "PSE driver does not support status report");
-		return -EOPNOTSUPP;
+	mutex_lock(&pcdev->lock);
+	ret = ops->pi_get_admin_state(pcdev, psec->id, &admin_state);
+	if (ret)
+		goto out;
+	status->podl_admin_state = admin_state.podl_admin_state;
+	status->c33_admin_state = admin_state.c33_admin_state;
+
+	ret = ops->pi_get_pw_status(pcdev, psec->id, &pw_status);
+	if (ret)
+		goto out;
+	status->podl_pw_status = pw_status.podl_pw_status;
+	status->c33_pw_status = pw_status.c33_pw_status;
+
+	if (ops->pi_get_ext_state) {
+		struct pse_ext_state_info ext_state_info = {0};
+
+		ret = ops->pi_get_ext_state(pcdev, psec->id,
+					    &ext_state_info);
+		if (ret)
+			goto out;
+
+		memcpy(&status->c33_ext_state_info,
+		       &ext_state_info.c33_ext_state_info,
+		       sizeof(status->c33_ext_state_info));
 	}
 
-	mutex_lock(&pcdev->lock);
-	err = ops->ethtool_get_status(pcdev, psec->id, extack, status);
-	mutex_unlock(&pcdev->lock);
+	if (ops->pi_get_pw_class) {
+		ret = ops->pi_get_pw_class(pcdev, psec->id);
+		if (ret < 0)
+			goto out;
 
-	return err;
+		status->c33_pw_class = ret;
+	}
+
+	if (ops->pi_get_actual_pw) {
+		ret = ops->pi_get_actual_pw(pcdev, psec->id);
+		if (ret < 0)
+			goto out;
+
+		status->c33_actual_pw = ret;
+	}
+
+	if (ops->pi_get_pw_limit) {
+		ret = ops->pi_get_pw_limit(pcdev, psec->id);
+		if (ret < 0)
+			goto out;
+
+		status->c33_avail_pw_limit = ret;
+	}
+
+	if (ops->pi_get_pw_limit_ranges) {
+		struct pse_pw_limit_ranges pw_limit_ranges = {0};
+
+		ret = ops->pi_get_pw_limit_ranges(pcdev, psec->id,
+						  &pw_limit_ranges);
+		if (ret < 0)
+			goto out;
+
+		status->c33_pw_limit_ranges =
+			pw_limit_ranges.c33_pw_limit_ranges;
+		status->c33_pw_limit_nb_ranges = ret;
+	}
+out:
+	mutex_unlock(&psec->pcdev->lock);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(pse_ethtool_get_status);
 
diff --git a/drivers/net/pse-pd/pse_regulator.c b/drivers/net/pse-pd/pse_regulator.c
index 64ab36974fe0..86360056b2f5 100644
--- a/drivers/net/pse-pd/pse_regulator.c
+++ b/drivers/net/pse-pd/pse_regulator.c
@@ -60,9 +60,19 @@ pse_reg_pi_is_enabled(struct pse_controller_dev *pcdev, int id)
 }
 
 static int
-pse_reg_ethtool_get_status(struct pse_controller_dev *pcdev, unsigned long id,
-			   struct netlink_ext_ack *extack,
-			   struct pse_control_status *status)
+pse_reg_pi_get_admin_state(struct pse_controller_dev *pcdev, int id,
+			   struct pse_admin_state *admin_state)
+{
+	struct pse_reg_priv *priv = to_pse_reg(pcdev);
+
+	admin_state->podl_admin_state = priv->admin_state;
+
+	return 0;
+}
+
+static int
+pse_reg_pi_get_pw_status(struct pse_controller_dev *pcdev, int id,
+			 struct pse_pw_status *pw_status)
 {
 	struct pse_reg_priv *priv = to_pse_reg(pcdev);
 	int ret;
@@ -72,18 +82,18 @@ pse_reg_ethtool_get_status(struct pse_controller_dev *pcdev, unsigned long id,
 		return ret;
 
 	if (!ret)
-		status->podl_pw_status = ETHTOOL_PODL_PSE_PW_D_STATUS_DISABLED;
+		pw_status->podl_pw_status =
+			ETHTOOL_PODL_PSE_PW_D_STATUS_DISABLED;
 	else
-		status->podl_pw_status =
+		pw_status->podl_pw_status =
 			ETHTOOL_PODL_PSE_PW_D_STATUS_DELIVERING;
 
-	status->podl_admin_state = priv->admin_state;
-
 	return 0;
 }
 
 static const struct pse_controller_ops pse_reg_ops = {
-	.ethtool_get_status = pse_reg_ethtool_get_status,
+	.pi_get_admin_state = pse_reg_pi_get_admin_state,
+	.pi_get_pw_status = pse_reg_pi_get_pw_status,
 	.pi_enable = pse_reg_pi_enable,
 	.pi_is_enabled = pse_reg_pi_is_enabled,
 	.pi_disable = pse_reg_pi_disable,
diff --git a/drivers/net/pse-pd/tps23881.c b/drivers/net/pse-pd/tps23881.c
index b87c391ae0f5..f735b6917f8b 100644
--- a/drivers/net/pse-pd/tps23881.c
+++ b/drivers/net/pse-pd/tps23881.c
@@ -201,14 +201,13 @@ static int tps23881_pi_is_enabled(struct pse_controller_dev *pcdev, int id)
 	return enabled;
 }
 
-static int tps23881_ethtool_get_status(struct pse_controller_dev *pcdev,
-				       unsigned long id,
-				       struct netlink_ext_ack *extack,
-				       struct pse_control_status *status)
+static int
+tps23881_pi_get_admin_state(struct pse_controller_dev *pcdev, int id,
+			    struct pse_admin_state *admin_state)
 {
 	struct tps23881_priv *priv = to_tps23881_priv(pcdev);
 	struct i2c_client *client = priv->client;
-	bool enabled, delivering;
+	bool enabled;
 	u8 chan;
 	u16 val;
 	int ret;
@@ -220,28 +219,56 @@ static int tps23881_ethtool_get_status(struct pse_controller_dev *pcdev,
 	chan = priv->port[id].chan[0];
 	val = tps23881_calc_val(ret, chan, 0, BIT(chan % 4));
 	enabled = !!(val);
-	val = tps23881_calc_val(ret, chan, 4, BIT(chan % 4));
-	delivering = !!(val);
 
 	if (priv->port[id].is_4p) {
 		chan = priv->port[id].chan[1];
 		val = tps23881_calc_val(ret, chan, 0, BIT(chan % 4));
 		enabled &= !!(val);
+	}
+
+	/* Return enabled status only if both channel are on this state */
+	if (enabled)
+		admin_state->c33_admin_state =
+			ETHTOOL_C33_PSE_ADMIN_STATE_ENABLED;
+	else
+		admin_state->c33_admin_state =
+			ETHTOOL_C33_PSE_ADMIN_STATE_DISABLED;
+
+	return 0;
+}
+
+static int
+tps23881_pi_get_pw_status(struct pse_controller_dev *pcdev, int id,
+			  struct pse_pw_status *pw_status)
+{
+	struct tps23881_priv *priv = to_tps23881_priv(pcdev);
+	struct i2c_client *client = priv->client;
+	bool delivering;
+	u8 chan;
+	u16 val;
+	int ret;
+
+	ret = i2c_smbus_read_word_data(client, TPS23881_REG_PW_STATUS);
+	if (ret < 0)
+		return ret;
+
+	chan = priv->port[id].chan[0];
+	val = tps23881_calc_val(ret, chan, 4, BIT(chan % 4));
+	delivering = !!(val);
+
+	if (priv->port[id].is_4p) {
+		chan = priv->port[id].chan[1];
 		val = tps23881_calc_val(ret, chan, 4, BIT(chan % 4));
 		delivering &= !!(val);
 	}
 
 	/* Return delivering status only if both channel are on this state */
 	if (delivering)
-		status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_DELIVERING;
-	else
-		status->c33_pw_status = ETHTOOL_C33_PSE_PW_D_STATUS_DISABLED;
-
-	/* Return enabled status only if both channel are on this state */
-	if (enabled)
-		status->c33_admin_state = ETHTOOL_C33_PSE_ADMIN_STATE_ENABLED;
+		pw_status->c33_pw_status =
+			ETHTOOL_C33_PSE_PW_D_STATUS_DELIVERING;
 	else
-		status->c33_admin_state = ETHTOOL_C33_PSE_ADMIN_STATE_DISABLED;
+		pw_status->c33_pw_status =
+			ETHTOOL_C33_PSE_PW_D_STATUS_DISABLED;
 
 	return 0;
 }
@@ -664,7 +691,8 @@ static const struct pse_controller_ops tps23881_ops = {
 	.pi_enable = tps23881_pi_enable,
 	.pi_disable = tps23881_pi_disable,
 	.pi_is_enabled = tps23881_pi_is_enabled,
-	.ethtool_get_status = tps23881_ethtool_get_status,
+	.pi_get_admin_state = tps23881_pi_get_admin_state,
+	.pi_get_pw_status = tps23881_pi_get_pw_status,
 };
 
 static const char fw_parity_name[] = "ti/tps23881/tps23881-parity-14.bin";