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From:   Sowjanya Komatineni <skomatineni@nvidia.com>
To:     <thierry.reding@gmail.com>, <jonathanh@nvidia.com>,
        <talho@nvidia.com>, <skomatineni@nvidia.com>, <broonie@kernel.org>,
        <robh+dt@kernel.org>, <mark.rutland@arm.com>,
        <kyarlagadda@nvidia.com>
CC:     <ldewangan@nvidia.com>, <linux-tegra@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <linux-spi@vger.kernel.org>,
        <devicetree@vger.kernel.org>
Subject: [PATCH V1 25/26] spi: expand mode and mode_bits support
Date:   Tue, 26 Mar 2019 22:56:46 -0700
Message-ID: <1553666207-11414-25-git-send-email-skomatineni@nvidia.com>
In-Reply-To: <1553666207-11414-1-git-send-email-skomatineni@nvidia.com>
References: <1553666207-11414-1-git-send-email-skomatineni@nvidia.com>
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mode and mode_bits is declared as u16 and all bits are used.

This patch changes mode and mode_bits to be u32 to allow for more mode
configurations.

Some SPI Master controllers support configuring Least significant byte
first or Most significant byte first order for transfers. Also some SPI
slave devices expect bytes to be in Least significant first order and
some devices expect Most significant first order.

This patch creates SPI_LSBYTE_FIRST mode for this purpose.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 include/linux/spi/spi.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index a0975cf76cf6..0032aa47dea0 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -143,7 +143,7 @@ struct spi_device {
 	u32			max_speed_hz;
 	u8			chip_select;
 	u8			bits_per_word;
-	u16			mode;
+	u32			mode;
 #define	SPI_CPHA	0x01			/* clock phase */
 #define	SPI_CPOL	0x02			/* clock polarity */
 #define	SPI_MODE_0	(0|0)			/* (original MicroWire) */
@@ -164,6 +164,7 @@ struct spi_device {
 #define	SPI_TX_OCTAL	0x2000			/* transmit with 8 wires */
 #define	SPI_RX_OCTAL	0x4000			/* receive with 8 wires */
 #define	SPI_3WIRE_HIZ	0x8000			/* high impedance turnaround */
+#define SPI_LSBYTE_FIRST	0x10000		/* per-word bytes-on-wire */
 	int			irq;
 	void			*controller_state;
 	void			*controller_data;
@@ -439,7 +440,7 @@ struct spi_controller {
 	u16			dma_alignment;
 
 	/* spi_device.mode flags understood by this controller driver */
-	u16			mode_bits;
+	u32			mode_bits;
 
 	/* bitmask of supported bits_per_word for transfers */
 	u32			bits_per_word_mask;
-- 
2.7.4