[U-Boot] [PATCH] serial: Make full device search optional

[Derald Woods]

On Jan 29, 2018 6:57 AM, "Alexander Graf" <agraf at suse.de> wrote:

Commit 608b0c4ad4e5ec0c ("serial: Use next serial device if probing fails")
added code to search for more serial devices if the default one was not
probed correctly.

Unfortunately, that breaks omap3_evm. So while investigating why that is
the case, let's disable the full search for everyone but bcm283x where it
is needed.

Fixes: 608b0c4ad4e5ec0c ("serial: Use next serial device if probing fails")
Reported-by: Derald D. Woods <woods.technical at gmail.com>
Signed-off-by: Alexander Graf <agraf at suse.de>

---

Derald, could you please test this patch and verify it does indeed unbreak
omap3_evm?



I will check later today. The board is not with me at the moment.

Derald



Thanks!
---
 arch/arm/Kconfig               |  1 +
 drivers/serial/Kconfig         | 12 ++++++++++++
 drivers/serial/serial-uclass.c | 13 +++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 30a6f6dc53..a423aa9629 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -550,6 +550,7 @@ config ARCH_BCM283X
        select DM_GPIO
        select OF_CONTROL
        select PL01X_SERIAL
+       select SERIAL_SEARCH_ALL
        imply FAT_WRITE

 config TARGET_VEXPRESS_CA15_TC2
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 3ffedba525..93e602e0ee 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -79,6 +79,18 @@ config SERIAL_RX_BUFFER_SIZE
        help
          The size of the RX buffer (needs to be power of 2)

+config SERIAL_SEARCH_ALL
+       bool "Search for serial devices after default one failed"
+       depends on DM_SERIAL
+       help
+         The serial subsystem only searches for a single serial device
+         that was instantiated, but does not check whether it was probed
+         correctly. With this option set, we make successful probing
+         mandatory and search for fallback serial devices if the default
+         device does not work.
+
+         If unsure, say N.
+
 config SPL_DM_SERIAL
        bool "Enable Driver Model for serial drivers in SPL"
        depends on DM_SERIAL
diff --git a/drivers/serial/serial-uclass.c b/drivers/serial/serial-uclass.c
index 68ca2d09d1..9891c20656 100644
--- a/drivers/serial/serial-uclass.c
+++ b/drivers/serial/serial-uclass.c
@@ -74,7 +74,9 @@ static void serial_find_console_or_panic(void)
 {
        const void *blob = gd->fdt_blob;
        struct udevice *dev;
+#ifdef CONFIG_SERIAL_SEARCH_ALL
        int ret;
+#endif

        if (CONFIG_IS_ENABLED(OF_PLATDATA)) {
                uclass_first_device(UCLASS_SERIAL, &dev);
@@ -113,6 +115,8 @@ static void serial_find_console_or_panic(void)
 #else
 #define INDEX 0
 #endif
+
+#ifdef CONFIG_SERIAL_SEARCH_ALL
                if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
                    !uclass_get_device(UCLASS_SERIAL, INDEX, &dev)) {
                        if (dev->flags & DM_FLAG_ACTIVATED) {
@@ -131,6 +135,15 @@ static void serial_find_console_or_panic(void)
                                return;
                        }
                }
+#else
+               if (!uclass_get_device_by_seq(UCLASS_SERIAL, INDEX, &dev) ||
+                   !uclass_get_device(UCLASS_SERIAL, INDEX, &dev) ||
+                   (!uclass_first_device(UCLASS_SERIAL, &dev) && dev)) {
+                       gd->cur_serial_dev = dev;
+                       return;
+               }
+#endif
+
 #undef INDEX
        }

--
2.12.3