[PATCH 1/6] mmc: sdhci: add platfrom get_max_timeout hook

[Shawn Guo]

On Wed, Dec 11, 2013 at 12:59:55PM +0800, Dong Aisheng wrote:
> On Wed, Dec 11, 2013 at 11:56 AM, Shawn Guo <shawn.guo at linaro.org> wrote:
> > On Wed, Dec 11, 2013 at 11:20:59AM +0800, Dong Aisheng wrote:
> >> No, the max_to is the max timeout counter value, you need to divide it
> >> by the timeout clock
> >> to get the timeout time.
> >> The defined of this API is return the max timeout value in
> >> miliseconds, so you need to
> >> divide the clock by 1000.
> >> None of these handles the detail bout discard_to.
> >
> > Let me start it over again.  Here is basically what your patch does.
> >
> > -     mmc->max_discard_to = (1 << 27) / host->timeout_clk;
> > +     if (host->ops->get_max_timeout)
> > +             mmc->max_discard_to = host->ops->get_max_timeout(host);
> >
> > The only thing that does not work for you in the existing code is the
> > (1 << 27) part, right?
> >
> > If so, why not just create a platform hook to return the correct thing
> > for you platform, i.e. (1 << 28)?
> >
> >         if (host->ops->get_max_timeout)
> >                 mmc->max_discard_to = host->ops->hook_foo(host);
> >
> > unsigned int esdhc_hook_foo(struct sdhci_host *host)
> > {
> >         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> >         struct pltfm_imx_data *imx_data = pltfm_host->priv;
> >
> >         return esdhc_is_usdhc(imx_data) ? 1 << 28 : 1 << 27;
> > }
> >
> > Such patch will be ease to be understood and less offensive to the
> > existing code, no?
> >
> 
> The example you give is not correct here.

Sorry.  Yes, there is a error in my example code.  What about this?

	mmc->max_discard_to = host->ops->hook_foo ? host->ops->hook_foo(host) : 1 << 27;
	mmc->max_discard_to /= host->timeout_clk;

Shawn