summaryrefslogtreecommitdiffstats
path: root/drivers/tty/serial
diff options
context:
space:
mode:
authorAnnaliese McDermond <nh6z@nh6z.net>2021-03-29 20:10:49 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-04-05 12:07:32 +0200
commit158e800e0fde91014812f5cdfb92ce812e3a33b4 (patch)
tree2c01fd2d9284e27357faf08c8a522cddedfab51b /drivers/tty/serial
parent3cd66593725a234662955baaf78d2ce5333de56d (diff)
downloadlinux-158e800e0fde91014812f5cdfb92ce812e3a33b4.tar.bz2
sc16is7xx: Defer probe if device read fails
A test was added to the probe function to ensure the device was actually connected and working before successfully completing a probe. If the device was actually there, but the I2C bus was not ready yet for whatever reason, the probe fails permanently. Change the probe so that we defer the probe on a regmap read failure so that we try the probe again when the dependent drivers are potentially loaded. This should not affect the case where the device truly isn't present because the probe will never successfully complete. Fixes: 2aa916e67db3 ("sc16is7xx: Read the LSR register for basic device presence check") Cc: stable@vger.kernel.org Signed-off-by: Annaliese McDermond <nh6z@nh6z.net> Link: https://lore.kernel.org/r/010101787f9c3fd8-c1815c00-2d6b-4c85-a96a-a13e68597fda-000000@us-west-2.amazonses.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial')
-rw-r--r--drivers/tty/serial/sc16is7xx.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index f86ec2d2635b..9adb8362578c 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -1196,7 +1196,7 @@ static int sc16is7xx_probe(struct device *dev,
ret = regmap_read(regmap,
SC16IS7XX_LSR_REG << SC16IS7XX_REG_SHIFT, &val);
if (ret < 0)
- return ret;
+ return -EPROBE_DEFER;
/* Alloc port structure */
s = devm_kzalloc(dev, struct_size(s, p, devtype->nr_uart), GFP_KERNEL);