On 23/04/2013 11:25 PM, Bibek Basu wrote: > -----Original Message----- > From: Linus Walleij [mailto:linus.wall...@linaro.org] > Sent: Wednesday, April 03, 2013 9:52 PM > To: Bibek Basu > Cc: linux-kernel@vger.kernel.org; Pritesh Raithatha > Subject: Re: [PATCH] pinctrl: tegra: add suspend-resume support > > On Thu, Mar 28, 2013 at 6:11 PM, Bibek Basu <bb...@nvidia.com> wrote: > > Hm I recognize this name :-) > You recognized me correctly. After all it's a small world:-) > > This patch adds suspend and resume callbacks to the pinctrl-tegra driver. > > Please be more verbose. How is this achieved? I have to guess what the code > is doing.. > > > +#ifdef CONFIG_PM_SLEEP > > + > > +static int pinctrl_suspend(void) > > +{ > > + int i, j; > > + u32 *pg_data = pmx->pg_data; > > + u32 *regs; > > + > > + for (i = 0; i < pmx->nbanks; i++) { > > + regs = pmx->regs[i]; > > + for (j = 0; j < pmx->regs_size[i] / 4; j++) > > + *pg_data++ = readl(regs++); > > + } > > + return 0; > > +} > > + > > +static void pinctrl_resume(void) > > +{ > > + int i, j; > > + u32 *pg_data = pmx->pg_data; > > + u32 *regs; > > + > > + for (i = 0; i < pmx->nbanks; i++) { > > + regs = pmx->regs[i]; > > + for (j = 0; j < pmx->regs_size[i] / 4; j++) > > + writel(*pg_data++, regs++); > > + } > > +} > > + > > +static struct syscore_ops pinctrl_syscore_ops = { > > + .suspend = pinctrl_suspend, > > + .resume = pinctrl_resume, > > +}; > > + > > +#endif > (...) > > +#ifdef CONFIG_PM_SLEEP > > + register_syscore_ops(&pinctrl_syscore_ops); > > +#endif > > So Stephen already commented that syscore ops is maybe too big a > sledgehammer for a fine-granular problem. > > I mainly want to know what is happening above, it looks like a state > save/restore for all registers or something like this? > Yeah, patch mainly saves and restores the registers. I am re-pushing the patch after incorporating stephen's changes.
regards Bibek > Yours, > Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
