linux-kernel - [PATCH v2 03/15] spi: Replace if-else-if by bitops and multiplications

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Message-Id: <20230710154932.68377-4-andriy.shevchenko@linux.intel.com>
Date:   Mon, 10 Jul 2023 18:49:20 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Mark Brown <broonie@...nel.org>,
        Cristian Ciocaltea <cristian.ciocaltea@...labora.com>,
        Yang Yingliang <yangyingliang@...wei.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Amit Kumar Mahapatra via Alsa-devel 
        <alsa-devel@...a-project.org>,
        Neil Armstrong <neil.armstrong@...aro.org>,
        Tharun Kumar P <tharunkumar.pasumarthi@...rochip.com>,
        Vijaya Krishna Nivarthi <quic_vnivarth@...cinc.com>,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>, linux-spi@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
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Cc:     Sanjay R Mehta <sanju.mehta@....com>,
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Subject: [PATCH v2 03/15] spi: Replace if-else-if by bitops and multiplications

Instead of if-else-if, simply call roundup_pow_of_two(BITS_PER_BYTES()).
Note, there is no division assumed as compiler may optimize it away.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
---
 drivers/spi/spi.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 6d74218cf38e..125dea8fae00 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -3643,13 +3643,7 @@ int spi_split_transfers_maxwords(struct spi_controller *ctlr,
 		size_t maxsize;
 		int ret;
 
-		if (xfer->bits_per_word <= 8)
-			maxsize = maxwords;
-		else if (xfer->bits_per_word <= 16)
-			maxsize = 2 * maxwords;
-		else
-			maxsize = 4 * maxwords;
-
+		maxsize = maxwords * roundup_pow_of_two(BITS_TO_BYTES(xfer->bits_per_word));
 		if (xfer->len > maxsize) {
 			ret = __spi_split_transfer_maxsize(ctlr, msg, &xfer,
 							   maxsize, gfp);
-- 
2.40.0.1.gaa8946217a0b