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

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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>,
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	Uwe Kleine-König <u.kleine-koenig@...gutronix.de>,
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Cc: Sanjay R Mehta <sanju.mehta@....com>,
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	Richard Cochran <richardcochran@...il.com>
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