Commit fb534f10 authored by Axel Lin's avatar Axel Lin Committed by Mark Brown
Browse files

spi: nuc900: Fix setting multiple bits settings in register 



The correct way to set multiple bits settings is always clear these
bit fields before set new settings.

Current code does not cause problem because the reset value of these
bit fields are 0, and these settings only set once during probe.

Signed-off-by: default avatarAxel Lin <axel.lin@ingics.com>
Signed-off-by: default avatarMark Brown <broonie@linaro.org>
parent 8120ff8c

drivers/spi/spi-nuc900.c

+8 −10
Original line number Original line Diff line number Diff line
@@ -38,7 +38,9 @@ 
/* usi register bit */

/* usi register bit */

#define ENINT		(0x01 << 17)

#define ENINT		(0x01 << 17)

#define ENFLG		(0x01 << 16)

#define ENFLG		(0x01 << 16)

#define SLEEP		(0x0f << 12)

#define TXNUM		(0x03 << 8)

#define TXNUM		(0x03 << 8)

#define TXBITLEN	(0x1f << 3)

#define TXNEG		(0x01 << 2)

#define TXNEG		(0x01 << 2)

#define RXNEG		(0x01 << 1)

#define RXNEG		(0x01 << 1)

#define LSB		(0x01 << 10)

#define LSB		(0x01 << 10)
@@ -116,19 +118,16 @@ static void nuc900_spi_chipsel(struct spi_device *spi, int value) 
	}

	}

}

}





static void nuc900_spi_setup_txnum(struct nuc900_spi *hw,

static void nuc900_spi_setup_txnum(struct nuc900_spi *hw, unsigned int txnum)

							unsigned int txnum)

{

{

	unsigned int val;

	unsigned int val;

	unsigned long flags;

	unsigned long flags;





	spin_lock_irqsave(&hw->lock, flags);

	spin_lock_irqsave(&hw->lock, flags);





	val = __raw_readl(hw->regs + USI_CNT);

	val = __raw_readl(hw->regs + USI_CNT) & ~TXNUM;





	if (!txnum)

	if (txnum)

		val &= ~TXNUM;

	else

		val |= txnum << 0x08;

		val |= txnum << 0x08;





	__raw_writel(val, hw->regs + USI_CNT);

	__raw_writel(val, hw->regs + USI_CNT);
@@ -145,7 +144,7 @@ static void nuc900_spi_setup_txbitlen(struct nuc900_spi *hw, 




	spin_lock_irqsave(&hw->lock, flags);

	spin_lock_irqsave(&hw->lock, flags);





	val = __raw_readl(hw->regs + USI_CNT);

	val = __raw_readl(hw->regs + USI_CNT) & ~TXBITLEN;





	val |= (txbitlen << 0x03);

	val |= (txbitlen << 0x03);
@@ -284,12 +283,11 @@ static void nuc900_set_sleep(struct nuc900_spi *hw, unsigned int sleep) 




	spin_lock_irqsave(&hw->lock, flags);

	spin_lock_irqsave(&hw->lock, flags);





	val = __raw_readl(hw->regs + USI_CNT);

	val = __raw_readl(hw->regs + USI_CNT) & ~SLEEP;





	if (sleep)

	if (sleep)

		val |= (sleep << 12);

		val |= (sleep << 12);

	else



		val &= ~(0x0f << 12);

	__raw_writel(val, hw->regs + USI_CNT);

	__raw_writel(val, hw->regs + USI_CNT);





	spin_unlock_irqrestore(&hw->lock, flags);

	spin_unlock_irqrestore(&hw->lock, flags);

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