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authorHans de Goede <hdegoede@redhat.com>2015-08-08 17:45:18 +0200
committerSimon Glass <sjg@chromium.org>2015-08-10 07:01:28 -0600
commit8c4585881de51e8c9a8b2207bb2fab1cd83728b8 (patch)
treecfcad27fd42925a6fba4d56bf14424b495e12f4b /drivers/serial
parentbd48c0617b5c7212e5bf22169e716da878842da4 (diff)
dm: serial: Add a REQUIRE_SERIAL_CONSOLE option for boards with no serial port
Currently the serial code assumes that there is always at least one serial port (and panics / crashes due to null pointer dereferences when there is none). This makes it impossible to use u-boot on boards where there is no (debug) serial port, because e.g. all uart pins are muxed to another function. This commit adds a CONFIG_REQUIRE_SERIAL_CONSOLE Kconfig option, which defaults to y (preserving existing behavior), which can be set to n on such boards to make them work. This commit only implements this for CONFIG_DM_SERIAL=y configs, as allowing running without a serial port for CONFIG_DM_SERIAL=n configs is non trivial, and is not necessary at this moment. Signed-off-by: Hans de Goede <hdegoede@redhat.com> Acked-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'drivers/serial')
-rw-r--r--drivers/serial/Kconfig11
-rw-r--r--drivers/serial/serial-uclass.c20
2 files changed, 28 insertions, 3 deletions
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index fd126a825f..a880eacfaf 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -1,3 +1,14 @@
+config REQUIRE_SERIAL_CONSOLE
+ bool "Require a serial port for console"
+ # Running without a serial console is not supported by the
+ # non-dm serial code
+ depends on DM_SERIAL
+ default y
+ help
+ Require a serial port for the console, and panic if none is found
+ during serial port initialization (default y). Set this to n on
+ boards which have no debug serial port whatsoever.
+
config DM_SERIAL
bool "Enable Driver Model for serial drivers"
depends on DM
diff --git a/drivers/serial/serial-uclass.c b/drivers/serial/serial-uclass.c
index bbc366b322..2a496979bc 100644
--- a/drivers/serial/serial-uclass.c
+++ b/drivers/serial/serial-uclass.c
@@ -78,7 +78,9 @@ static void serial_find_console_or_panic(void)
#undef INDEX
}
+#ifdef CONFIG_REQUIRE_SERIAL_CONSOLE
panic_str("No serial driver found");
+#endif
}
/* Called prior to relocation */
@@ -140,28 +142,40 @@ static int _serial_tstc(struct udevice *dev)
void serial_putc(char ch)
{
- _serial_putc(gd->cur_serial_dev, ch);
+ if (gd->cur_serial_dev)
+ _serial_putc(gd->cur_serial_dev, ch);
}
void serial_puts(const char *str)
{
- _serial_puts(gd->cur_serial_dev, str);
+ if (gd->cur_serial_dev)
+ _serial_puts(gd->cur_serial_dev, str);
}
int serial_getc(void)
{
+ if (!gd->cur_serial_dev)
+ return 0;
+
return _serial_getc(gd->cur_serial_dev);
}
int serial_tstc(void)
{
+ if (!gd->cur_serial_dev)
+ return 0;
+
return _serial_tstc(gd->cur_serial_dev);
}
void serial_setbrg(void)
{
- struct dm_serial_ops *ops = serial_get_ops(gd->cur_serial_dev);
+ struct dm_serial_ops *ops;
+
+ if (!gd->cur_serial_dev)
+ return;
+ ops = serial_get_ops(gd->cur_serial_dev);
if (ops->setbrg)
ops->setbrg(gd->cur_serial_dev, gd->baudrate);
}