linux-kernel - [PATCH v1 1/1] spi: Simplify conditionals in spi_set

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <20250331093915.4041600-1-andriy.shevchenko@linux.intel.com>
Date: Mon, 31 Mar 2025 12:39:15 +0300
From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To: Mark Brown <broonie@...nel.org>,
	Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
	linux-spi@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: [PATCH v1 1/1] spi: Simplify conditionals in spi_set_cs()

First of all, the (foo && bar) || (!foo && !bar) when foo and bar
are booleans is equivalent to (foo == bar). Second, reuse variable
that holds already the calculation of the SPI CS mode to be
active-high. No functional changes intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 drivers/spi/spi.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index ef755d11374d..3c6c70468899 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1077,10 +1077,8 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
 	 * Avoid calling into the driver (or doing delays) if the chip select
 	 * isn't actually changing from the last time this was called.
 	 */
-	if (!force && ((enable && spi->controller->last_cs_index_mask == spi->cs_index_mask &&
-			spi_is_last_cs(spi)) ||
-		       (!enable && spi->controller->last_cs_index_mask == spi->cs_index_mask &&
-			!spi_is_last_cs(spi))) &&
+	if (!force && (enable == spi_is_last_cs(spi)) &&
+	    (spi->controller->last_cs_index_mask == spi->cs_index_mask) &&
 	    (spi->controller->last_cs_mode_high == (spi->mode & SPI_CS_HIGH)))
 		return;
 
@@ -1089,9 +1087,9 @@ static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
 	spi->controller->last_cs_index_mask = spi->cs_index_mask;
 	for (idx = 0; idx < SPI_CS_CNT_MAX; idx++)
 		spi->controller->last_cs[idx] = enable ? spi_get_chipselect(spi, 0) : SPI_INVALID_CS;
-	spi->controller->last_cs_mode_high = spi->mode & SPI_CS_HIGH;
 
-	if (spi->mode & SPI_CS_HIGH)
+	spi->controller->last_cs_mode_high = spi->mode & SPI_CS_HIGH;
+	if (spi->controller->last_cs_mode_high)
 		enable = !enable;
 
 	/*
-- 
2.47.2