linux-kernel - [PATCH 5.1 117/371] spi: fix ctrl->num

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190724191733.628145439@linuxfoundation.org>
Date:   Wed, 24 Jul 2019 21:17:49 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Tudor Ambarus <tudor.ambarus@...rochip.com>,
        Mark Brown <broonie@...nel.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.1 117/371] spi: fix ctrl->num_chipselect constraint

[ Upstream commit f9481b08220d7dc1ff21e296a330ee8b721b44e4 ]

at91sam9g25ek showed the following error at probe:
atmel_spi f0000000.spi: Using dma0chan2 (tx) and dma0chan3 (rx)
for DMA transfers
atmel_spi: probe of f0000000.spi failed with error -22

Commit 0a919ae49223 ("spi: Don't call spi_get_gpio_descs() before device name is set")
moved the calling of spi_get_gpio_descs() after ctrl->dev is set,
but didn't move the !ctrl->num_chipselect check. When there are
chip selects in the device tree, the spi-atmel driver lets the
SPI core discover them when registering the SPI master.
The ctrl->num_chipselect is thus expected to be set by
spi_get_gpio_descs().

Move the !ctlr->num_chipselect after spi_get_gpio_descs() as it was
before the aforementioned commit. While touching this block, get rid
of the explicit comparison with 0 and update the commenting style.

Fixes: 0a919ae49223 ("spi: Don't call spi_get_gpio_descs() before device name is set")
Signed-off-by: Tudor Ambarus <tudor.ambarus@...rochip.com>
Signed-off-by: Mark Brown <broonie@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/spi/spi.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index a83fcddf1dad..7f6fb383d7a7 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -2281,11 +2281,6 @@ int spi_register_controller(struct spi_controller *ctlr)
 	if (status)
 		return status;
 
-	/* even if it's just one always-selected device, there must
-	 * be at least one chipselect
-	 */
-	if (ctlr->num_chipselect == 0)
-		return -EINVAL;
 	if (ctlr->bus_num >= 0) {
 		/* devices with a fixed bus num must check-in with the num */
 		mutex_lock(&board_lock);
@@ -2356,6 +2351,13 @@ int spi_register_controller(struct spi_controller *ctlr)
 		}
 	}
 
+	/*
+	 * Even if it's just one always-selected device, there must
+	 * be at least one chipselect.
+	 */
+	if (!ctlr->num_chipselect)
+		return -EINVAL;
+
 	status = device_add(&ctlr->dev);
 	if (status < 0) {
 		/* free bus id */
-- 
2.20.1