From 6d710b769c1f5f0d55c9ad9bb49b7dce009ec103 Mon Sep 17 00:00:00 2001 From: Hugo Villeneuve Date: Thu, 21 Dec 2023 18:18:09 -0500 Subject: serial: sc16is7xx: add check for unsupported SPI modes during probe The original comment is confusing because it implies that variants other than the SC16IS762 supports other SPI modes beside SPI_MODE_0. Extract from datasheet: The SC16IS762 differs from the SC16IS752 in that it supports SPI clock speeds up to 15 Mbit/s instead of the 4 Mbit/s supported by the SC16IS752... In all other aspects, the SC16IS762 is functionally and electrically the same as the SC16IS752. The same is also true of the SC16IS760 variant versus the SC16IS740 and SC16IS750 variants. For all variants, only SPI mode 0 is supported. Change comment and abort probing if the specified SPI mode is not SPI_MODE_0. Fixes: 2c837a8a8f9f ("sc16is7xx: spi interface is added") Cc: Signed-off-by: Hugo Villeneuve Link: https://lore.kernel.org/r/20231221231823.2327894-3-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/sc16is7xx.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c index 17b90f971f96..798fa115b28a 100644 --- a/drivers/tty/serial/sc16is7xx.c +++ b/drivers/tty/serial/sc16is7xx.c @@ -1733,7 +1733,10 @@ static int sc16is7xx_spi_probe(struct spi_device *spi) /* Setup SPI bus */ spi->bits_per_word = 8; - /* only supports mode 0 on SC16IS762 */ + /* For all variants, only mode 0 is supported */ + if ((spi->mode & SPI_MODE_X_MASK) != SPI_MODE_0) + return dev_err_probe(&spi->dev, -EINVAL, "Unsupported SPI mode\n"); + spi->mode = spi->mode ? : SPI_MODE_0; spi->max_speed_hz = spi->max_speed_hz ? : 15000000; ret = spi_setup(spi); -- cgit v1.2.3