This is a note to let you know that I've just added the patch titled

serial: sc16is7xx: add check for unsupported SPI modes during probe

to my tty git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git in the tty-testing branch.

The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.)

The patch will be merged to the tty-next branch sometime soon, after it passes testing, and the merge window is open.

If you have any questions about this process, please let me know.

From 6d710b769c1f5f0d55c9ad9bb49b7dce009ec103 Mon Sep 17 00:00:00 2001 From: Hugo Villeneuve hvilleneuve@dimonoff.com 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: stable@vger.kernel.org Signed-off-by: Hugo Villeneuve hvilleneuve@dimonoff.com Link: https://lore.kernel.org/r/20231221231823.2327894-3-hugo@hugovil.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serial/sc16is7xx.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)

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);