drivers: can: add Kconfig option for specifying the sample point margin

Add a Kconfig option for setting the maximum acceptable deviation in sample
point location (permille).

Signed-off-by: Henrik Brix Andersen <[email protected]>

Author: henrikbrixandersen

drivers/can/Kconfig

@@ -38,6 +38,14 @@ config CAN_DEFAULT_BITRATE_DATA
 	  Default initial CAN data phase bitrate in bits/s. This can be overridden per CAN controller
 	  using the "bitrate-data" devicetree property.
 
+config CAN_SAMPLE_POINT_MARGIN
+	int "Maximum acceptable sample point location deviation"
+	default 50
+	range 0 1000
+	help
+	  Maximum acceptable deviation in sample point location (permille). A value of 50 means +/-
+	  5 percentage points margin allowed.
+
 config CAN_SHELL
 	bool "CAN shell"
 	depends on SHELL

drivers/can/can_common.c

@@ -12,9 +12,6 @@
 
 LOG_MODULE_REGISTER(can_common, CONFIG_CAN_LOG_LEVEL);
 
-/* Maximum acceptable deviation in sample point location (permille) */
-#define SAMPLE_POINT_MARGIN 50
-
 /* CAN sync segment is always one time quantum */
 #define CAN_SYNC_SEG 1
 
@@ -402,7 +399,7 @@ int z_impl_can_set_bitrate(const struct device *dev, uint32_t bitrate)
 		return ret;
 	}
 
-	if (ret > SAMPLE_POINT_MARGIN) {
+	if (ret > CONFIG_CAN_SAMPLE_POINT_MARGIN) {
 		return -ERANGE;
 	}
 
@@ -448,7 +445,7 @@ int z_impl_can_set_bitrate_data(const struct device *dev, uint32_t bitrate_data)
 		return ret;
 	}
 
-	if (ret > SAMPLE_POINT_MARGIN) {
+	if (ret > CONFIG_CAN_SAMPLE_POINT_MARGIN) {
 		return -ERANGE;
 	}