[PATCH v2 3/5] spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate

From: Alain Volmat <alain.volmat@st.com>
To: <broonie@kernel.org>, <amelie.delaunay@st.com>
Cc: <mcoquelin.stm32@gmail.com>, <alexandre.torgue@st.com>,
	<linux-spi@vger.kernel.org>,
	<linux-stm32@st-md-mailman.stormreply.com>,
	<linux-arm-kernel@lists.infradead.org>,
	<linux-kernel@vger.kernel.org>, <fabrice.gasnier@st.com>,
	<alain.volmat@st.com>
Subject: [PATCH v2 3/5] spi: stm32: fix stm32_spi_prepare_mbr in case of odd clk_rate
Date: Mon, 10 Aug 2020 09:12:36 +0200	[thread overview]
Message-ID: <1597043558-29668-4-git-send-email-alain.volmat@st.com> (raw)
In-Reply-To: <1597043558-29668-1-git-send-email-alain.volmat@st.com>

From: Amelie Delaunay <amelie.delaunay@st.com>

Fix spi->clk_rate when it is odd to the nearest lowest even value because
minimum SPI divider is 2.

Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Alain Volmat <alain.volmat@st.com>
---
v2: identical to v1

 drivers/spi/spi-stm32.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index e5450233f3f8..571dea72bf7e 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -441,7 +441,8 @@ static int stm32_spi_prepare_mbr(struct stm32_spi *spi, u32 speed_hz,
 {
 	u32 div, mbrdiv;
 
-	div = DIV_ROUND_UP(spi->clk_rate, speed_hz);
+	/* Ensure spi->clk_rate is even */
+	div = DIV_ROUND_UP(spi->clk_rate & ~0x1, speed_hz);
 
 	/*
 	 * SPI framework set xfer->speed_hz to master->max_speed_hz if
-- 
2.7.4

