Hello Doug, On 06/20/2014 11:42 PM, Doug Anderson wrote: > On the ARM Chromebook tps65090 has two masters: the AP (the main > processor running linux) and the EC (the embedded controller). The AP > is allowed to mess with FETs but the EC is in charge of charge control. > > The tps65090 interupt line is routed to both the AP and the EC, which > can cause quite a headache. Having two people adjusting masks and > acking interrupts is a recipe for disaster. > > In the shipping kernel we had a hack to have the AP pay attention to > the IRQ but not to ack it. It also wasn't supposed to configure the > IRQ in any way. That hack allowed us to detect when the device was > charging without messing with the EC's state. > > The current tps65090 infrastructure makes the above difficult, and it > was a bit of a hack to begin with. Rather than uglify the driver to > support it, just extend the driver's existing notion of "no irq" to > the charger. This makes the charger code poll every 2 seconds for AC > detect, which is sufficient. > > For proper functioning, requires (mfd: tps65090: Don't tell child > devices we have an IRQ if we don't). If we don't have that patch > we'll simply fail to probe on devices without an interrupt (just like > we did before this patch). > > Signed-off-by: Doug Anderson <dianders@xxxxxxxxxxxx> > --- > Changes in v2: > - Split noirq (polling mode) changes into MFD and charger > > This patch has been sent up a number of times with no response. It's > needed to make the charger work on exynos5250-snow, > exynos5420-peach-pit, and exynos5800-peach-pi. It was originally part > of a series as <https://patchwork.kernel.org/patch/4042751/> and the > rest of the series has long since landed. > Looks good to me. Also since this patch makes optional to get an IRQ, the following annoying message is not shown anymore: [ 2.132944] tps65090-charger tps65090-charger: Unable to get charger irq = -6 Reviewed-by: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx> Tested-by: Javier Martinez Canillas <javier.martinez@xxxxxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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