Re: Dual SJA1000 can controllers on SMP system.

[Marc Kleine-Budde <mkl@pengutronix.de>]

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On 06/17/2013 08:10 AM, Mirza Krak wrote:
> Aah off course. The low-level device driver is sja1000_platform.c. The
> functions I am using are sp_read_reg8 and sp_write_reg8 which I have
> slightly modified. Since I don't use multiplexed bus functionality I
> write the address first.
> 
>   static u8 sp_read_reg8(const struct sja1000_priv *priv, int reg)
> {
>     iowrite8(reg, priv->reg_base);
      ^^^^^^^^
>     return ioread8(priv->reg_base + 0x20);
> }
> 
> static void sp_write_reg8(const struct sja1000_priv *priv, int reg, u8 val)
> {
>     iowrite8(reg, priv->reg_base);
      ^^^^^^^^
>     iowrite8(val, (priv->reg_base + 0x20));
> }

Can you post a proper patch, so that we can see what you have changed?

You probably have a nice race condition here. The two iowrites have to
be atomic.

Marc
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