From: Trent Piepho <tpiepho@gmail.com>
Date: Sat, 14 Dec 2013 02:27:44 +0000 (-0800)
Subject: spi: Order fields in spi_device for better packing
X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=89c1f60746106755e29dcc3db9f22e37000891ef;p=deliverable%2Flinux.git

spi: Order fields in spi_device for better packing

Now that spi_device->mode is a u16, the chip_select, bits_per_mode,
and mode fields pack poorly, taking 8 bytes:  four data and four
padding.  By moving (u8)bits_per_word up one position, to after
(u8)chip_select, they pack better and only use 4 bytes.

Signed-off-by: Trent Piepho <tpiepho@gmail.com>
Reviewed-by: Sourav Poddar <sourav.poddar@ti.com>
Tested-by: Sourav Poddar <sourav.poddar@ti.com>g
Signed-off-by: Mark Brown <broonie@linaro.org>
---

diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 8c62ba74dd91..27a882978c15 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -75,6 +75,7 @@ struct spi_device {
 	struct spi_master	*master;
 	u32			max_speed_hz;
 	u8			chip_select;
+	u8			bits_per_word;
 	u16			mode;
 #define	SPI_CPHA	0x01			/* clock phase */
 #define	SPI_CPOL	0x02			/* clock polarity */
@@ -92,7 +93,6 @@ struct spi_device {
 #define	SPI_TX_QUAD	0x200			/* transmit with 4 wires */
 #define	SPI_RX_DUAL	0x400			/* receive with 2 wires */
 #define	SPI_RX_QUAD	0x800			/* receive with 4 wires */
-	u8			bits_per_word;
 	int			irq;
 	void			*controller_state;
 	void			*controller_data;