drivers/syslog: add cdcacm channel

drivers/syslog/Kconfig

@@ -259,6 +259,21 @@ config SYSLOG_RPMSG
 	---help---
 		Use the RPMSG as a SYSLOG output device, send message to remote proc.
 
+config SYSLOG_CDCACM
+	bool "Log to CDCACM"
+	depends on CDCACM
+	default n
+	---help---
+		Use the CDCACM as a SYSLOG output device, send message to remote proc.
+
+config SYSLOG_CDCACM_MINOR
+	int "The syslog CDCACM minor number"
+	depends on SYSLOG_CDCACM
+	default 0
+	---help---
+		If there are more than one CDCACM devices, then a device minor number
+		may also need to be provided. Default: 0
+
 config SYSLOG_STREAM
 	bool "Log to stream"
 	default n
@@ -269,15 +284,15 @@ config SYSLOG_STREAM
 
 config SYSLOG_CONSOLE
 	bool "Log to /dev/console"
-	default !ARCH_LOWPUTC && !SYSLOG_CHAR && !RAMLOG_SYSLOG && !SYSLOG_RPMSG && !SYSLOG_RTT
+	default !ARCH_LOWPUTC && !SYSLOG_CHAR && !RAMLOG_SYSLOG && !SYSLOG_RPMSG && !SYSLOG_RTT && !SYSLOG_CDCACM
 	depends on DEV_CONSOLE
 	select SYSLOG_REGISTER
 	---help---
 		Use the system console as a SYSLOG output device.
 
 config SYSLOG_DEFAULT
 	bool "Default SYSLOG device"
-	default ARCH_LOWPUTC && !SYSLOG_CHAR && !RAMLOG_SYSLOG && !SYSLOG_RPMSG && !SYSLOG_RTT && !SYSLOG_CONSOLE
+	default ARCH_LOWPUTC && !SYSLOG_CHAR && !RAMLOG_SYSLOG && !SYSLOG_RPMSG && !SYSLOG_RTT && !SYSLOG_CDCACM && !SYSLOG_CONSOLE
 	---help---
 		syslog() interfaces will be present, but all output will go to the
 		up_putc(ARCH_LOWPUTC == y) or bit-bucket(ARCH_LOWPUTC == n).

drivers/syslog/syslog_channel.c

@@ -47,6 +47,10 @@
 #  include <nuttx/segger/rtt.h>
 #endif
 
+#ifdef CONFIG_SYSLOG_CDCACM
+#  include <nuttx/usb/cdcacm.h>
+#endif
+
 #ifdef CONFIG_ARCH_LOWPUTC
 #  include <nuttx/arch.h>
 #endif
@@ -57,13 +61,20 @@
  * Private Function Prototypes
  ****************************************************************************/
 
-#if defined(CONFIG_SYSLOG_DEFAULT)
+#ifdef CONFIG_SYSLOG_DEFAULT
 static int syslog_default_putc(FAR syslog_channel_t *channel,
                                int ch);
 static ssize_t syslog_default_write(FAR syslog_channel_t *channel,
                                     FAR const char *buffer, size_t buflen);
 #endif
 
+#ifdef CONFIG_SYSLOG_CDCACM
+static int syslog_cdcacm_putc(FAR struct syslog_channel_s *channel,
+                              int ch);
+static ssize_t syslog_cdcacm_write(FAR struct syslog_channel_s *channel,
+                                   FAR const char *buffer, size_t buflen);
+#endif
+
 /****************************************************************************
  * Private Data
  ****************************************************************************/
@@ -133,6 +144,25 @@ static syslog_channel_t g_rtt_channel =
 };
 #endif
 
+#ifdef CONFIG_SYSLOG_CDCACM
+static const struct syslog_channel_ops_s g_cdcacm_channel_ops =
+{
+  syslog_cdcacm_putc,
+  syslog_cdcacm_putc,
+  NULL,
+  syslog_cdcacm_write,
+  syslog_cdcacm_write
+};
+
+static struct syslog_channel_s g_cdcacm_channel =
+{
+  &g_cdcacm_channel_ops
+#  ifdef CONFIG_SYSLOG_IOCTL
+  , "cdcacm"
+#  endif
+};
+#endif
+
 #ifdef CONFIG_SYSLOG_DEFAULT
 static const struct syslog_channel_ops_s g_default_channel_ops =
 {
@@ -206,7 +236,10 @@ g_syslog_channel[CONFIG_SYSLOG_MAX_CHANNELS] =
   &g_rpmsg_channel,
 #endif
 #ifdef CONFIG_SYSLOG_RTT
-  &g_rtt_channel
+  &g_rtt_channel,
+#endif
+#ifdef CONFIG_SYSLOG_CDCACM
+  &g_cdcacm_channel
 #endif
 };
 
@@ -296,6 +329,27 @@ static ssize_t syslog_default_write(FAR syslog_channel_t *channel,
 }
 #endif
 
+#ifdef CONFIG_SYSLOG_CDCACM
+static int syslog_cdcacm_putc(FAR struct syslog_channel_s *channel, int ch)
+{
+  char tmp;
+
+  tmp = ch;
+  cdcacm_write(&tmp, 1);
+
+  UNUSED(channel);
+  return ch;
+}
+
+static ssize_t syslog_cdcacm_write(FAR struct syslog_channel_s *channel,
+                                   FAR const char *buffer, size_t buflen)
+{
+  UNUSED(channel);
+
+  return cdcacm_write(buffer, buflen);
+}
+#endif
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/

drivers/usbdev/cdcacm.c

@@ -235,6 +235,10 @@ static void    cdcuart_dmareceive(FAR struct uart_dev_s *dev);
  * Private Data
  ****************************************************************************/
 
+#ifdef CONFIG_SYSLOG_CDCACM
+static FAR struct cdcacm_dev_s *g_syslog_cdcacm;
+#endif
+
 /* USB class device *********************************************************/
 
 static const struct usbdevclass_driverops_s g_driverops =
@@ -2775,6 +2779,76 @@ static void cdcuart_dmareceive(FAR struct uart_dev_s *dev)
  * Public Functions
  ****************************************************************************/
 
+#ifdef CONFIG_SYSLOG_CDCACM
+/****************************************************************************
+ * Name: cdcacm_write
+ *
+ * Description:
+ *   This provides a cdcacm write method for syslog devices that support
+ *   multiple byte writes
+ *
+ * Input Parameters:
+ *   buffer - The buffer containing the data to be output
+ *   buflen - The number of bytes in the buffer
+ *
+ * Returned Value:
+ *   On success, the number of characters written is returned.  A negated
+ *   errno value is returned on any failure.
+ *
+ ****************************************************************************/
+
+ssize_t cdcacm_write(FAR const char *buffer, size_t buflen)
+{
+  FAR struct cdcacm_dev_s *priv = g_syslog_cdcacm;
+  size_t len = 0;
+
+  while (len < buflen)
+    {
+      irqstate_t flags;
+
+      if (!priv || !priv->ctrlline)
+        {
+          return -EINVAL;
+        }
+
+      flags = enter_critical_section();
+
+      if (cdcuart_txready(&priv->serdev))
+        {
+          ssize_t ret = cdcuart_sendbuf(&priv->serdev,
+                                        buffer + len,
+                                        buflen - len);
+          if (ret < 0)
+            {
+              leave_critical_section(flags);
+              return ret;
+            }
+
+          len += ret;
+        }
+
+      leave_critical_section(flags);
+    }
+
+  return buflen;
+}
+
+/****************************************************************************
+ * Name: cdcacm_disable_syslog
+ *
+ * Description:
+ *   Disable CDCACM syslog channel by clearing the globle pointer.
+ *   This function is used in specific situation, such as must disable
+ *   cdcacm log printing when usb re-enumeration.
+ *
+ ****************************************************************************/
+
+void cdcacm_disable_syslog(void)
+{
+  g_syslog_cdcacm = NULL;
+}
+#endif
+
 /****************************************************************************
  * Name: cdcacm_classobject
  *
@@ -2904,6 +2978,14 @@ int cdcacm_classobject(int minor, FAR struct usbdev_devinfo_s *devinfo,
     }
 
   *classdev = &drvr->drvr;
+
+#ifdef CONFIG_SYSLOG_CDCACM
+  if (minor == CONFIG_SYSLOG_CDCACM_MINOR)
+    {
+      g_syslog_cdcacm = priv;
+    }
+#endif
+
   return OK;
 
 errout_with_class:
@@ -3019,6 +3101,13 @@ void cdcacm_uninitialize(FAR struct usbdevclass_driver_s *classdev)
   char devname[CDCACM_DEVNAME_SIZE];
   int ret;
 
+#ifdef CONFIG_SYSLOG_CDCACM
+  if (g_syslog_cdcacm == priv)
+    {
+      g_syslog_cdcacm = NULL;
+    }
+#endif
+
   /* Disconnect in case we are connected */
 
   cdcacm_disconnect(classdev, priv->usbdev);

include/nuttx/usb/cdcacm.h

@@ -423,6 +423,40 @@ struct composite_devdesc_s;
 void cdcacm_get_composite_devdesc(struct composite_devdesc_s *dev);
 #endif
 
+/****************************************************************************
+ * Name: cdcacm_write
+ *
+ * Description:
+ *   This provides a cdcacm write method for syslog devices that support
+ *   multiple byte writes.
+ *
+ * Input Parameters:
+ *   buffer - The buffer containing the data to be output
+ *   buflen - The number of bytes in the buffer
+ *
+ * Returned Value:
+ *   On success, the number of characters written is returned.  A negated
+ *   errno value is returned on any failure.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_SYSLOG_CDCACM
+ssize_t cdcacm_write(FAR const char *buffer, size_t buflen);
+#endif
+
+/****************************************************************************
+ * Name: cdcacm_disable_syslog
+ *
+ * Description:
+ *   Disable CDCACM syslog channel by clearing the globle pointer.
+ *   This function is used in specific situation, such as must disable
+ *   cdcacm log printing when usb re-enumeration.
+ *
+ ****************************************************************************/
+#ifdef CONFIG_SYSLOG_CDCACM
+void cdcacm_disable_syslog(void);
+#endif
+
 #undef EXTERN
 #if defined(__cplusplus)
 }