[PATCH v3 1/3] i2c: pxa: Add support for the I2C units found in Armada 3700

Gregory CLEMENT gregory.clement at free-electrons.com
Wed Nov 9 02:21:06 PST 2016


Hi Romain,


You was too fast I didn't have time to commnent about Baruch suggestion.

 On mer., nov. 09 2016, Romain Perier <romain.perier at free-electrons.com> wrote:

> The Armada 3700 has two I2C controllers that is compliant with the I2C
> Bus Specificiation 2.1, supports multi-master and different bus speed:
> Standard mode (up to 100 KHz), Fast mode (up to 400 KHz),
> High speed mode (up to 3.4 Mhz).
>
> This IP block has a lot of similarity with the PXA, except some register
> offsets and bitfield. This commits adds a basic support for this I2C
> unit.
>
> Signed-off-by: Romain Perier <romain.perier at free-electrons.com>
> Tested-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
> ---
>
> Changes in v3:
>  - Replaced the type of hm_mask and fm_mask by unsigned int,
>    instead of unsigned long.

[...]


>  #define ISR_RWM		(1 << 0)	   /* read/write mode */
> @@ -193,6 +204,8 @@ struct pxa_i2c {
>  	unsigned char		master_code;
>  	unsigned long		rate;
>  	bool			highmode_enter;
> +	unsigned int		fm_mask;
> +	unsigned int		hs_mask;

These masks are used with writel and readl which use an u32. So the
better is to use this type.

Gregory

>  };
>  
>  #define _IBMR(i2c)	((i2c)->reg_ibmr)
> @@ -503,8 +516,8 @@ static void i2c_pxa_reset(struct pxa_i2c *i2c)
>  		writel(i2c->slave_addr, _ISAR(i2c));
>  
>  	/* set control register values */
> -	writel(I2C_ICR_INIT | (i2c->fast_mode ? ICR_FM : 0), _ICR(i2c));
> -	writel(readl(_ICR(i2c)) | (i2c->high_mode ? ICR_HS : 0), _ICR(i2c));
> +	writel(I2C_ICR_INIT | (i2c->fast_mode ? i2c->fm_mask : 0), _ICR(i2c));
> +	writel(readl(_ICR(i2c)) | (i2c->high_mode ? i2c->hs_mask : 0), _ICR(i2c));
>  



-- 
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com



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