Revert "Merge [...] #11310 from OTAkeys/make_uart_stdio_rx_optional"

This change was breaking (dependencies for) ethos, shell, etc, as well as an unknown
number of external apps (API change.) See #11525 for more details.

Fixes #11525.

Makefile.dep

@@ -397,18 +397,8 @@ ifneq (,$(filter stdio_rtt,$(USEMODULE)))
   USEMODULE += xtimer
 endif
 
-ifneq (,$(filter shell,$(USEMODULE)))
-  ifneq (,$(filter stdio_uart,$(USEMODULE)))
-    USEMODULE += stdio_uart_rx
-  endif
-endif
-
-ifneq (,$(filter stdio_uart_rx,$(USEMODULE)))
-  USEMODULE += isrpipe
-  USEMODULE += stdio_uart
-endif
-
 ifneq (,$(filter stdio_uart,$(USEMODULE)))
+  USEMODULE += isrpipe
   FEATURES_REQUIRED += periph_uart
 endif
 

makefiles/pseudomodules.inc.mk

@@ -70,7 +70,6 @@ PSEUDOMODULES += sock
 PSEUDOMODULES += sock_ip
 PSEUDOMODULES += sock_tcp
 PSEUDOMODULES += sock_udp
-PSEUDOMODULES += stdio_uart_rx
 
 # print ascii representation in function od_hex_dump()
 PSEUDOMODULES += od_string

sys/stdio_uart/stdio_uart.c

@@ -27,8 +27,6 @@
  * @}
  */
 
-#include <errno.h>
-
 #include "stdio_uart.h"
 
 #include "board.h"
@@ -47,31 +45,16 @@ extern ethos_t ethos;
 #define ENABLE_DEBUG 0
 #include "debug.h"
 
-#ifdef MODULE_STDIO_UART_RX
+
 static char _rx_buf_mem[STDIO_UART_RX_BUFSIZE];
 isrpipe_t stdio_uart_isrpipe = ISRPIPE_INIT(_rx_buf_mem);
-#endif
 
 void stdio_init(void)
 {
-    uart_rx_cb_t cb;
-    void *arg;
-
-#ifdef MODULE_STDIO_UART_RX
-    cb = (uart_rx_cb_t) isrpipe_write_one;
-    arg = &stdio_uart_isrpipe;
-#else
-#ifdef USE_ETHOS_FOR_STDIO
-#error "ethos needs stdio_uart_rx"
-#endif
-    cb = NULL;
-    arg = NULL;
-#endif
-
 #ifndef USE_ETHOS_FOR_STDIO
-    uart_init(STDIO_UART_DEV, STDIO_UART_BAUDRATE, cb, arg);
+    uart_init(STDIO_UART_DEV, STDIO_UART_BAUDRATE, (uart_rx_cb_t) isrpipe_write_one, &stdio_uart_isrpipe);
 #else
-    uart_init(ETHOS_UART, ETHOS_BAUDRATE, cb, arg);
+    uart_init(ETHOS_UART, ETHOS_BAUDRATE, (uart_rx_cb_t) isrpipe_write_one, &stdio_uart_isrpipe);
 #endif
 #if MODULE_VFS
     vfs_bind_stdio();
@@ -80,13 +63,7 @@ void stdio_init(void)
 
 ssize_t stdio_read(void* buffer, size_t count)
 {
-#ifdef MODULE_STDIO_UART_RX
     return (ssize_t)isrpipe_read(&stdio_uart_isrpipe, (char *)buffer, count);
-#else
-    (void)buffer;
-    (void)count;
-    return -ENOTSUP;
-#endif
 }
 
 ssize_t stdio_write(const void* buffer, size_t len)