[U-Boot] [PATCH 03/24] mxc_i2c: create tx_byte function

[Marek Vasut]

Dear Troy Kisky,

> Use tx_byte function instead of having 3 copies
> of the code.
> 
> Signed-off-by: Troy Kisky <troy.kisky at boundarydevices.com>
> ---
>  drivers/i2c/mxc_i2c.c |   72
> +++++++++++++++---------------------------------- 1 file changed, 21
> insertions(+), 51 deletions(-)
> 
> diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
> index 0b46c9c..0fd508a 100644
> --- a/drivers/i2c/mxc_i2c.c
> +++ b/drivers/i2c/mxc_i2c.c
> @@ -33,6 +33,7 @@
>  #include <common.h>
>  #include <asm/arch/clock.h>
>  #include <asm/arch/imx-regs.h>
> +#include <asm/errno.h>
>  #include <asm/io.h>
>  #include <i2c.h>
> 
> @@ -207,17 +208,21 @@ int i2c_imx_trx_complete(void)
>  		udelay(1);
>  	}
> 
> -	return 1;
> +	return -ETIMEDOUT;
>  }
> 
> -/*
> - * Check if the transaction was ACKed
> - */
> -int i2c_imx_acked(void)
> +static int tx_byte(struct mxc_i2c_regs *i2c_regs, u8 byte)
>  {
> -	struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
> +	unsigned ret;
> 
> -	return readb(&i2c_regs->i2sr) & I2SR_RX_NO_AK;
> +	writeb(byte, &i2c_regs->i2dr);
> +	ret = i2c_imx_trx_complete();
> +	if (ret < 0)
> +		return ret;
> +	ret = readb(&i2c_regs->i2sr);
> +	if (ret & I2SR_RX_NO_AK)
> +		return -ENODEV;
> +	return 0;
>  }
> 
>  /*
> @@ -271,30 +276,6 @@ void i2c_imx_stop(void)
>  }
> 
>  /*
> - * Set chip address and access mode
> - *
> - * read = 1: READ access
> - * read = 0: WRITE access
> - */
> -int i2c_imx_set_chip_addr(uchar chip, int read)
> -{
> -	struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
> -	int ret;
> -
> -	writeb((chip << 1) | read, &i2c_regs->i2dr);
> -
> -	ret = i2c_imx_trx_complete();
> -	if (ret)
> -		return ret;
> -
> -	ret = i2c_imx_acked();
> -	if (ret)
> -		return ret;
> -
> -	return ret;
> -}
> -
> -/*
>   * Write register address
>   */
>  int i2c_imx_set_reg_addr(uint addr, int alen)
> @@ -303,14 +284,8 @@ int i2c_imx_set_reg_addr(uint addr, int alen)
>  	int ret = 0;
> 
>  	while (alen--) {
> -		writeb((addr >> (alen * 8)) & 0xff, &i2c_regs->i2dr);
> -
> -		ret = i2c_imx_trx_complete();
> -		if (ret)
> -			break;
> -
> -		ret = i2c_imx_acked();
> -		if (ret)
> +		ret =  tx_byte(i2c_regs, (addr >> (alen * 8)) & 0xff);
> +		if (ret < 0)
>  			break;
>  	}
> 
> @@ -322,13 +297,14 @@ int i2c_imx_set_reg_addr(uint addr, int alen)
>   */
>  int i2c_probe(uchar chip)
>  {
> +	struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)I2C_BASE;
>  	int ret;
> 
>  	ret = i2c_imx_start();
>  	if (ret)
>  		return ret;
> 
> -	ret = i2c_imx_set_chip_addr(chip, 0);
> +	ret = tx_byte(i2c_regs, chip << 1);
>  	if (ret)
>  		return ret;
> 
> @@ -352,7 +328,7 @@ int i2c_read(uchar chip, uint addr, int alen, uchar
> *buf, int len) return ret;
> 
>  	/* write slave address */
> -	ret = i2c_imx_set_chip_addr(chip, 0);
> +	ret = tx_byte(i2c_regs, chip << 1);
>  	if (ret)
>  		return ret;
> 
> @@ -364,7 +340,7 @@ int i2c_read(uchar chip, uint addr, int alen, uchar
> *buf, int len) temp |= I2CR_RSTA;
>  	writeb(temp, &i2c_regs->i2cr);
> 
> -	ret = i2c_imx_set_chip_addr(chip, 1);
> +	ret = tx_byte(i2c_regs, (chip << 1) | 1);

Isn't this | 1 and | 0 stuff #define-d somewhere? I think there was 
I2C_READ_SOMETHING in i2c.h and I2C_WRITE_SOMETHING...

>  	if (ret)
>  		return ret;
> 

Otherwise
Acked-by: Marek Vasut <marex at denx.de>

Best regards,
Marek Vasut