Revert "Merge branch 'dsa-rtnl'"

This reverts commit 965e6b262f48257dbdb51b565ecfd84877a0ab5f, reversing
changes made to 4d98bb0d7ec2d0b417df6207b0bafe1868bad9f8.

3 files changed, 23 insertions, 71 deletions

diff --git a/drivers/net/dsa/sja1105/sja1105.h b/drivers/net/dsa/sja1105/sja1105.h
index 21dba16af097..808419f3b808 100644
--- a/drivers/net/dsa/sja1105/sja1105.h
+++ b/drivers/net/dsa/sja1105/sja1105.h
@@ -261,8 +261,6 @@ struct sja1105_private {
 	 * the switch doesn't confuse them with one another.
 	 */
 	struct mutex mgmt_lock;
-	/* Serializes access to the dynamic config interface */
-	struct mutex dynamic_config_lock;
 	struct devlink_region **regions;
 	struct sja1105_cbs_entry *cbs;
 	struct mii_bus *mdio_base_t1;
diff --git a/drivers/net/dsa/sja1105/sja1105_dynamic_config.c b/drivers/net/dsa/sja1105/sja1105_dynamic_config.c
index 7729d3f8b7f5..f2049f52833c 100644
--- a/drivers/net/dsa/sja1105/sja1105_dynamic_config.c
+++ b/drivers/net/dsa/sja1105/sja1105_dynamic_config.c
@@ -1170,56 +1170,6 @@ const struct sja1105_dynamic_table_ops sja1110_dyn_ops[BLK_IDX_MAX_DYN] = {
 	},
 };
 
-#define SJA1105_DYNAMIC_CONFIG_SLEEP_US		10
-#define SJA1105_DYNAMIC_CONFIG_TIMEOUT_US	100000
-
-static int
-sja1105_dynamic_config_poll_valid(struct sja1105_private *priv,
-				  struct sja1105_dyn_cmd *cmd,
-				  const struct sja1105_dynamic_table_ops *ops)
-{
-	u8 packed_buf[SJA1105_MAX_DYN_CMD_SIZE] = {};
-	int rc;
-
-	/* We don't _need_ to read the full entry, just the command area which
-	 * is a fixed SJA1105_SIZE_DYN_CMD. But our cmd_packing() API expects a
-	 * buffer that contains the full entry too. Additionally, our API
-	 * doesn't really know how many bytes into the buffer does the command
-	 * area really begin. So just read back the whole entry.
-	 */
-	rc = sja1105_xfer_buf(priv, SPI_READ, ops->addr, packed_buf,
-			      ops->packed_size);
-	if (rc)
-		return rc;
-
-	/* Unpack the command structure, and return it to the caller in case it
-	 * needs to perform further checks on it (VALIDENT).
-	 */
-	memset(cmd, 0, sizeof(*cmd));
-	ops->cmd_packing(packed_buf, cmd, UNPACK);
-
-	/* Hardware hasn't cleared VALID => still working on it */
-	return cmd->valid ? -EAGAIN : 0;
-}
-
-/* Poll the dynamic config entry's control area until the hardware has
- * cleared the VALID bit, which means we have confirmation that it has
- * finished processing the command.
- */
-static int
-sja1105_dynamic_config_wait_complete(struct sja1105_private *priv,
-				     struct sja1105_dyn_cmd *cmd,
-				     const struct sja1105_dynamic_table_ops *ops)
-{
-	int rc;
-
-	return read_poll_timeout(sja1105_dynamic_config_poll_valid,
-				 rc, rc != -EAGAIN,
-				 SJA1105_DYNAMIC_CONFIG_SLEEP_US,
-				 SJA1105_DYNAMIC_CONFIG_TIMEOUT_US,
-				 false, priv, cmd, ops);
-}
-
 /* Provides read access to the settings through the dynamic interface
  * of the switch.
  * @blk_idx	is used as key to select from the sja1105_dynamic_table_ops.
@@ -1246,6 +1196,7 @@ int sja1105_dynamic_config_read(struct sja1105_private *priv,
 	struct sja1105_dyn_cmd cmd = {0};
 	/* SPI payload buffer */
 	u8 packed_buf[SJA1105_MAX_DYN_CMD_SIZE] = {0};
+	int retries = 3;
 	int rc;
 
 	if (blk_idx >= BLK_IDX_MAX_DYN)
@@ -1283,21 +1234,33 @@ int sja1105_dynamic_config_read(struct sja1105_private *priv,
 		ops->entry_packing(packed_buf, entry, PACK);
 
 	/* Send SPI write operation: read config table entry */
-	mutex_lock(&priv->dynamic_config_lock);
 	rc = sja1105_xfer_buf(priv, SPI_WRITE, ops->addr, packed_buf,
 			      ops->packed_size);
-	if (rc < 0) {
-		mutex_unlock(&priv->dynamic_config_lock);
-		return rc;
-	}
-
-	rc = sja1105_dynamic_config_wait_complete(priv, &cmd, ops);
-	mutex_unlock(&priv->dynamic_config_lock);
 	if (rc < 0)
 		return rc;
 
-	if (!cmd.valident && !(ops->access & OP_VALID_ANYWAY))
-		return -ENOENT;
+	/* Loop until we have confirmation that hardware has finished
+	 * processing the command and has cleared the VALID field
+	 */
+	do {
+		memset(packed_buf, 0, ops->packed_size);
+
+		/* Retrieve the read operation's result */
+		rc = sja1105_xfer_buf(priv, SPI_READ, ops->addr, packed_buf,
+				      ops->packed_size);
+		if (rc < 0)
+			return rc;
+
+		cmd = (struct sja1105_dyn_cmd) {0};
+		ops->cmd_packing(packed_buf, &cmd, UNPACK);
+
+		if (!cmd.valident && !(ops->access & OP_VALID_ANYWAY))
+			return -ENOENT;
+		cpu_relax();
+	} while (cmd.valid && --retries);
+
+	if (cmd.valid)
+		return -ETIMEDOUT;
 
 	/* Don't dereference possibly NULL pointer - maybe caller
 	 * only wanted to see whether the entry existed or not.
@@ -1353,16 +1316,8 @@ int sja1105_dynamic_config_write(struct sja1105_private *priv,
 		ops->entry_packing(packed_buf, entry, PACK);
 
 	/* Send SPI write operation: read config table entry */
-	mutex_lock(&priv->dynamic_config_lock);
 	rc = sja1105_xfer_buf(priv, SPI_WRITE, ops->addr, packed_buf,
 			      ops->packed_size);
-	if (rc < 0) {
-		mutex_unlock(&priv->dynamic_config_lock);
-		return rc;
-	}
-
-	rc = sja1105_dynamic_config_wait_complete(priv, &cmd, ops);
-	mutex_unlock(&priv->dynamic_config_lock);
 	if (rc < 0)
 		return rc;
 
diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c
index c343effe2e96..ef46ae53ab56 100644
--- a/drivers/net/dsa/sja1105/sja1105_main.c
+++ b/drivers/net/dsa/sja1105/sja1105_main.c
@@ -3365,7 +3365,6 @@ static int sja1105_probe(struct spi_device *spi)
 	priv->ds = ds;
 
 	mutex_init(&priv->ptp_data.lock);
-	mutex_init(&priv->dynamic_config_lock);
 	mutex_init(&priv->mgmt_lock);
 
 	rc = sja1105_parse_dt(priv);