From 9ee9497dd41d4da82a44a49cac84f61b16f9538a Mon Sep 17 00:00:00 2001
From: Xianzi Lu <xianzi.lu@agile-robots.com>
Date: Tue, 23 Jul 2024 13:14:24 +0800
Subject: [PATCH] Fix "No such file or directory" error when using multiple
 masters and RTDM

This error occurs when we are using multiple masters along with RTDM.
Device minor is not set and device numbers are always one when registering
an RTDM device.
Seems there is no need to change the legacy Xenomai 2.6 RTDM driver, because
the device will be identified by a name instead of a device minor.
---
 master/master.h          |  4 ++++
 master/module.c          | 10 ++++------
 master/rtdm_xenomai_v3.c |  3 ++-
 3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/master/master.h b/master/master.h
index 77bd97be..a1125e85 100644
--- a/master/master.h
+++ b/master/master.h
@@ -112,6 +112,10 @@
  */
 #define EC_EXT_RING_SIZE 32
 
+/** Maximum number of masters.
+ */
+#define EC_MAX_MASTERS 32
+
 /****************************************************************************/
 
 /** EtherCAT master phase.
diff --git a/master/module.c b/master/module.c
index 3e81f25e..b8156a1d 100644
--- a/master/module.c
+++ b/master/module.c
@@ -35,8 +35,6 @@
 
 /****************************************************************************/
 
-#define MAX_MASTERS 32 /**< Maximum number of masters. */
-
 /****************************************************************************/
 
 int __init ec_init_module(void);
@@ -50,9 +48,9 @@ int ec_mac_is_broadcast(const uint8_t *);
 
 /****************************************************************************/
 
-static char *main_devices[MAX_MASTERS]; /**< Main devices parameter. */
+static char *main_devices[EC_MAX_MASTERS]; /**< Main devices parameter. */
 static unsigned int master_count; /**< Number of masters. */
-static char *backup_devices[MAX_MASTERS]; /**< Backup devices parameter. */
+static char *backup_devices[EC_MAX_MASTERS]; /**< Backup devices parameter. */
 static unsigned int backup_count; /**< Number of backup devices. */
 static unsigned int debug_level;  /**< Debug level parameter. */
 static unsigned int run_on_cpu = 0xffffffff; /**< Bind created kernel threads
@@ -65,7 +63,7 @@ static struct semaphore master_sem; /**< Master semaphore. */
 dev_t device_number; /**< Device number for master cdevs. */
 struct class *class; /**< Device class. */
 
-static uint8_t macs[MAX_MASTERS][2][ETH_ALEN]; /**< MAC addresses. */
+static uint8_t macs[EC_MAX_MASTERS][2][ETH_ALEN]; /**< MAC addresses. */
 
 char *ec_master_version_str = EC_MASTER_VERSION; /**< Version string. */
 
@@ -125,7 +123,7 @@ int __init ec_init_module(void)
     }
 
     // zero MAC addresses
-    memset(macs, 0x00, sizeof(uint8_t) * MAX_MASTERS * 2 * ETH_ALEN);
+    memset(macs, 0x00, sizeof(uint8_t) * EC_MAX_MASTERS * 2 * ETH_ALEN);
 
     // process MAC parameters
     for (i = 0; i < master_count; i++) {
diff --git a/master/rtdm_xenomai_v3.c b/master/rtdm_xenomai_v3.c
index 0cd3b577..230e4172 100644
--- a/master/rtdm_xenomai_v3.c
+++ b/master/rtdm_xenomai_v3.c
@@ -131,7 +131,7 @@ static struct rtdm_driver ec_rtdm_driver = {
 						    222,
 						    0),
 	.device_flags		= RTDM_NAMED_DEVICE,
-	.device_count		= 1,
+	.device_count		= EC_MAX_MASTERS,
 	.context_size		= sizeof(struct ec_rtdm_context),
 	.ops = {
 		.open		= ec_rtdm_open,
@@ -163,6 +163,7 @@ int ec_rtdm_dev_init(ec_rtdm_dev_t *rtdm_dev, ec_master_t *master)
 	dev->driver = &ec_rtdm_driver;
 	dev->device_data = rtdm_dev;
 	dev->label = "EtherCAT%u";
+	dev->minor = master->index;
 
 	ret = rtdm_dev_register(dev);
 	if (ret) {