[PATCH 03/18] tty: serial: samsung: add gs101 earlycon support

From: Tudor Ambarus
Date: Wed Jan 10 2024 - 05:21:40 EST


The entire bus (PERIC) on which the GS101 serial resides only allows
32-bit register accesses. The reg-io-width dt property is disallowed
for the "google,gs101-uart" compatible and instead the iotype is
inferred from the compatible. Always set UPIO_MEM32 iotype for the
gs101 earlycon.

Reviewed-by: Peter Griffin <peter.griffin@xxxxxxxxxx>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
---
drivers/tty/serial/samsung_tty.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
index 20ec6ef1a52f..74bc5151dad4 100644
--- a/drivers/tty/serial/samsung_tty.c
+++ b/drivers/tty/serial/samsung_tty.c
@@ -2810,6 +2810,17 @@ OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
OF_EARLYCON_DECLARE(artpec8, "axis,artpec8-uart",
s5pv210_early_console_setup);

+static int __init gs101_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ /* gs101 always expects MMIO32 register accesses. */
+ device->port.iotype = UPIO_MEM32;
+
+ return s5pv210_early_console_setup(device, opt);
+}
+
+OF_EARLYCON_DECLARE(gs101, "google,gs101-uart", gs101_early_console_setup);
+
/* Apple S5L */
static int __init apple_s5l_early_console_setup(struct earlycon_device *device,
const char *opt)
--
2.43.0.472.g3155946c3a-goog