From 1bb74504a8f1c605019e76ae1806297c14c05d49 Mon Sep 17 00:00:00 2001
From: "Anton D. Kachalov" <mouse@yandex-team.ru>
Date: Mon, 3 Aug 2015 15:32:51 +0300
Subject: [PATCH] Add support for custom platform IOCTL on UART

Signed-off-by: Anton D. Kachalov <mouse@yandex-team.ru>
---
 drivers/serial/Kconfig            |  4 ++++
 drivers/serial/uart_16550.c       | 10 +++++++++-
 include/nuttx/serial/uart_16550.h |  4 +++-
 3 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index b2b3b20a55..6e7d7865e5 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -318,6 +318,10 @@ config 16550_SUPRESS_CONFIG
 		that configures the 16550_UART.  In that case, you may want to
 		just leave the existing console configuration in place.  Default: n
 
+config SERIAL_UART_ARCH_IOCTL
+	bool "Platform has own custom IOCTL"
+	default n
+
 config 16550_REGINCR
 	int "Address increment between 16550 registers"
 	default 1
diff --git a/drivers/serial/uart_16550.c b/drivers/serial/uart_16550.c
index 5b7401c7a2..ffa7f7a4c9 100644
--- a/drivers/serial/uart_16550.c
+++ b/drivers/serial/uart_16550.c
@@ -864,7 +864,15 @@ static int u16550_ioctl(struct file *filep, int cmd, unsigned long arg)
   struct inode      *inode = filep->f_inode;
   struct uart_dev_s *dev   = inode->i_private;
   struct u16550_s   *priv  = (struct u16550_s*)dev->priv;
-  int                ret   = OK;
+
+#ifdef CONFIG_SERIAL_UART_ARCH_IOCTL
+  int ret = uart_ioctl(filep, cmd, arg);
+
+  if (ret != -ENOTTY)
+    {
+      return ret;
+    }
+#endif
 
   switch (cmd)
     {
diff --git a/include/nuttx/serial/uart_16550.h b/include/nuttx/serial/uart_16550.h
index de37fb5502..9a35d99286 100644
--- a/include/nuttx/serial/uart_16550.h
+++ b/include/nuttx/serial/uart_16550.h
@@ -336,16 +336,18 @@ typedef uint32_t uart_addrwidth_t;
  ************************************************************************************/
 
 /************************************************************************************
- * Name: uart_getreg(), uart_putreg()
+ * Name: uart_getreg(), uart_putreg(), uart_ioctl()
  *
  * Description:
  *   These functions must be provided by the processor-specific code in order to
  *   correctly access 16550 registers
+ *   uart_ioctl() is optional to provide custom IOCTLs
  *
  ************************************************************************************/
 
 uart_datawidth_t uart_getreg(uart_addrwidth_t base, unsigned int offset);
 void uart_putreg(uart_addrwidth_t base, unsigned int offset, uart_datawidth_t value);
+int uart_ioctl(struct file *filep, int cmd, unsigned long arg);
 
 #endif /* CONFIG_16550_UART */
 #endif /* __INCLUDE_NUTTX_SERIAL_UART_16550_H */