mlxsw: core_hwmon: Calculate MLXSW_HWMON_ATTR_COUNT more accurately

Currently the value of MLXSW_HWMON_ATTR_COUNT is calculated not really
accurate.

Add several defines to make the calculation clearer and easier to
change.

Calculate the precise high bound of number of attributes that may be
needed.

Signed-off-by: Amit Cohen <amitc@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/core_hwmon.c

@@ -12,8 +12,17 @@
 #include "core.h"
 #include "core_env.h"
 
-#define MLXSW_HWMON_TEMP_SENSOR_MAX_COUNT 127
-#define MLXSW_HWMON_ATTR_COUNT (MLXSW_HWMON_TEMP_SENSOR_MAX_COUNT * 4 + \
+#define MLXSW_HWMON_SENSORS_MAX_COUNT 64
+#define MLXSW_HWMON_MODULES_MAX_COUNT 64
+#define MLXSW_HWMON_GEARBOXES_MAX_COUNT 32
+
+#define MLXSW_HWMON_ATTR_PER_SENSOR 3
+#define MLXSW_HWMON_ATTR_PER_MODULE 5
+#define MLXSW_HWMON_ATTR_PER_GEARBOX 4
+
+#define MLXSW_HWMON_ATTR_COUNT (MLXSW_HWMON_SENSORS_MAX_COUNT * MLXSW_HWMON_ATTR_PER_SENSOR + \
+				MLXSW_HWMON_MODULES_MAX_COUNT * MLXSW_HWMON_ATTR_PER_MODULE + \
+				MLXSW_HWMON_GEARBOXES_MAX_COUNT * MLXSW_HWMON_ATTR_PER_GEARBOX + \
 				MLXSW_MFCR_TACHOS_MAX + MLXSW_MFCR_PWMS_MAX)
 
 struct mlxsw_hwmon_attr {