mlxsw: Assorted fixes

This patchset contains several fixes for the mlxsw driver.

Patch #1 - Fixes buffer size in I2C mailbox buffer. Patch #2 - Sets limitation of chunk size in I2C transaction. Patch #3 - Fixes module label names based on MTCAP sensor counter

Vadim Pasternak (3):
mlxsw: i2c: Fix chunk size setting in output mailbox buffer
mlxsw: i2c: Limit single transaction buffer size
mlxsw: core_hwmon: Adjust module label names based on MTCAP sensor
counter

 drivers/net/ethernet/mellanox/mlxsw/core_hwmon.c | 3 ++-
 drivers/net/ethernet/mellanox/mlxsw/i2c.c        | 5 +++--
 2 files changed, 5 insertions(+), 3 deletions(-)

2.41.0

From: Vadim Pasternak <[email protected]>

The driver reads commands output from the output mailbox. If the size of the output mailbox is not a multiple of the transaction / block size, then the driver will not issue enough read transactions to read the entire output, which can result in driver initialization errors.

Fix by determining the number of transactions using DIV_ROUND_UP().

---
 drivers/net/ethernet/mellanox/mlxsw/i2c.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

index 41298835a11e..47af7ef7e4ee 100644
@@ -444,7 +444,7 @@ mlxsw_i2c_cmd(struct device *dev, u16 opcode, u32 in_mod, size_t in_mbox_size,
 	} else {
 		/* No input mailbox is case of initialization query command. */
 		reg_size = MLXSW_I2C_MAX_DATA_SIZE;
-		num = reg_size / mlxsw_i2c->block_size;
+		num = DIV_ROUND_UP(reg_size, mlxsw_i2c->block_size);
 
 		if (mutex_lock_interruptible(&mlxsw_i2c->cmd.lock) < 0) {
 			dev_err(&client->dev, "Could not acquire lock");

2.41.0

From: Vadim Pasternak <[email protected]>

Maximum size of buffer is obtained from underlying I2C adapter and in case adapter allows I2C transaction buffer size greater than 100 bytes, transaction will fail due to firmware limitation.

As a result driver will fail initialization.

Limit the maximum size of transaction buffer by 100 bytes to fit to firmware.

Remove unnecessary calculation:
max_t(u16, MLXSW_I2C_BLK_DEF, quirk_size).
This condition can not happened.

---
 drivers/net/ethernet/mellanox/mlxsw/i2c.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

index 47af7ef7e4ee..d23f293e285c 100644
@@ -48,6 +48,7 @@
 #define MLXSW_I2C_MBOX_SIZE_BITS	12
 #define MLXSW_I2C_ADDR_BUF_SIZE		4
 #define MLXSW_I2C_BLK_DEF		32
+#define MLXSW_I2C_BLK_MAX		100
 #define MLXSW_I2C_RETRY			5
 #define MLXSW_I2C_TIMEOUT_MSECS		5000
 #define MLXSW_I2C_MAX_DATA_SIZE		256

@@ -653,7 +654,7 @@ static int mlxsw_i2c_probe(struct i2c_client *client)
 			return -EOPNOTSUPP;
 		}
 
-		mlxsw_i2c->block_size = max_t(u16, MLXSW_I2C_BLK_DEF,
+		mlxsw_i2c->block_size = min_t(u16, MLXSW_I2C_BLK_MAX,
 					      min_t(u16, quirks->max_read_len,
 						    quirks->max_write_len));
 	} else {

2.41.0

From: Vadim Pasternak <[email protected]>

Transceiver module temperature sensors are indexed after ASIC and platform sensors. The current label printing method does not take this into account and simply prints the index of the transceiver module sensor.

On new systems that have platform sensors this results in incorrect (shifted) transceiver module labels being printed:

$ sensors
[...]
front panel 002:  +37.0°C  (crit = +70.0°C, emerg = +75.0°C)
front panel 003:  +47.0°C  (crit = +70.0°C, emerg = +75.0°C)
[...]

Fix by taking the sensor count into account. After the fix:

$ sensors
[...]
front panel 001:  +37.0°C  (crit = +70.0°C, emerg = +75.0°C)
front panel 002:  +47.0°C  (crit = +70.0°C, emerg = +75.0°C)
[...]

---
 drivers/net/ethernet/mellanox/mlxsw/core_hwmon.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

index 70735068cf29..0fd290d776ff 100644
@@ -405,7 +405,8 @@ mlxsw_hwmon_module_temp_label_show(struct device *dev,
 			container_of(attr, struct mlxsw_hwmon_attr, dev_attr);
 
 	return sprintf(buf, "front panel %03u\n",
-		       mlxsw_hwmon_attr->type_index);
+		       mlxsw_hwmon_attr->type_index + 1 -
+		       mlxsw_hwmon_attr->mlxsw_hwmon_dev->sensor_count);
 }
 
 static ssize_t

2.41.0