From 955cd0545b6abcefd297832e38f90f6851fc2ada Mon Sep 17 00:00:00 2001 From: Alejandro Enrique Date: Wed, 14 May 2025 15:54:42 +0200 Subject: [PATCH] gnss: ubx: add support for the safeboot gpio U-Blox M8/M9 chip have a pin to start it in safeboot mode, to be used to recover from situations where the flash content has become corrupted and needs to be restored. If this pin is asserted at power up/reset, the receiver starts in safeboot mode and GNSS operation is disabled. Deassert the safeboot pin when probing this driver. Signed-off-by: Alejandro Enrique Reviewed-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20250911-ubx-safeboot-v3-2-32fe6b882a3c@geotab.com [ johan: deassert after requesting supplies ] Signed-off-by: Johan Hovold --- drivers/gnss/ubx.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/gnss/ubx.c b/drivers/gnss/ubx.c index 92402f6082c41..23894ff75ff91 100644 --- a/drivers/gnss/ubx.c +++ b/drivers/gnss/ubx.c @@ -66,6 +66,7 @@ static const struct gnss_serial_ops ubx_gserial_ops = { static int ubx_probe(struct serdev_device *serdev) { struct gnss_serial *gserial; + struct gpio_desc *safeboot; struct gpio_desc *reset; struct ubx_data *data; int ret; @@ -92,6 +93,13 @@ static int ubx_probe(struct serdev_device *serdev) if (ret < 0 && ret != -ENODEV) goto err_free_gserial; + /* Deassert safeboot */ + safeboot = devm_gpiod_get_optional(&serdev->dev, "safeboot", GPIOD_OUT_LOW); + if (IS_ERR(safeboot)) { + ret = PTR_ERR(safeboot); + goto err_free_gserial; + } + /* Deassert reset */ reset = devm_gpiod_get_optional(&serdev->dev, "reset", GPIOD_OUT_LOW); if (IS_ERR(reset)) { -- 2.47.3