lkml.org 
[lkml]   [2014]   [Jul]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RESEND PATCH v3] charger: tps65090: Allow charger module to be used when no irq
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@chromium.org>
> ---
> 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@collabora.co.uk>
Tested-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>


\
 
 \ /
  Last update: 2014-07-17 18:21    [W:3.654 / U:0.000 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site