Re: [PATCH v4] pinctrl: mediatek: Implement wake handler and suspend resume

[Hongzhou Yang]

On Mon, 2015-08-17 at 21:25 +0800, Yingjoe Chen wrote:
> On Mon, 2015-08-17 at 17:09 +0800, Daniel Kurtz wrote:
> > On Mon, Aug 17, 2015 at 3:52 PM, Yingjoe Chen <yingjoe.chen@xxxxxxxxxxxx> wrote:
> > > On Fri, 2015-08-14 at 16:38 +0800, maoguang.meng@xxxxxxxxxxxx wrote:
> > >> From: Maoguang Meng <maoguang.meng@xxxxxxxxxxxx>
> > >>
> > >> This patch implement irq_set_wake to get who is wakeup source and
> > >> setup on suspend resume.
> > >>
> > >> Signed-off-by: Maoguang Meng <maoguang.meng@xxxxxxxxxxxx>
> > >>
> > >> ---
> > >> changes since v3:
> > >> -add a comment in mtk_eint_chip_read_mask.
> > >> -delete ALIGN when allocate eint_offsets.ports.
> > >> -fix unrelated change.
> > >>
> > >> changes since v2:
> > >> -modify irq_wake to handle irq wakeup source.
> > >> -allocate two buffers separately.
> > >> -fix some codestyle.
> > >>
> > >> Changes since v1:
> > >> -implement irq_wake handler.
> > >> ---
> > >>
> > >>  drivers/pinctrl/mediatek/pinctrl-mt8173.c     |  1 +
> > >>  drivers/pinctrl/mediatek/pinctrl-mtk-common.c | 91 ++++++++++++++++++++++++++-
> > >>  drivers/pinctrl/mediatek/pinctrl-mtk-common.h |  4 ++
> > >>  3 files changed, 95 insertions(+), 1 deletion(-)
> > >>
> > >> diff --git a/drivers/pinctrl/mediatek/pinctrl-mt8173.c b/drivers/pinctrl/mediatek/pinctrl-mt8173.c
> > >> index d0c811d..ad27184 100644
> > >> --- a/drivers/pinctrl/mediatek/pinctrl-mt8173.c
> > >> +++ b/drivers/pinctrl/mediatek/pinctrl-mt8173.c
> > >> @@ -385,6 +385,7 @@ static struct platform_driver mtk_pinctrl_driver = {
> > >>       .driver = {
> > >>               .name = "mediatek-mt8173-pinctrl",
> > >>               .of_match_table = mt8173_pctrl_match,
> > >> +             .pm = &mtk_eint_pm_ops,
> > >>       },
> > >>  };
> > >>
> > >> diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common.c b/drivers/pinctrl/mediatek/pinctrl-mtk-common.c
> > >> index ad1ea16..fe34ce9 100644
> > >> --- a/drivers/pinctrl/mediatek/pinctrl-mtk-common.c
> > >> +++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common.c
> > >> @@ -33,6 +33,7 @@
> > >>  #include <linux/mfd/syscon.h>
> > >>  #include <linux/delay.h>
> > >>  #include <linux/interrupt.h>
> > >> +#include <linux/pm.h>
> > >>  #include <dt-bindings/pinctrl/mt65xx.h>
> > >>
> > >>  #include "../core.h"
> > >> @@ -1062,6 +1063,77 @@ static int mtk_eint_set_type(struct irq_data *d,
> > >>       return 0;
> > >>  }
> > >>
> > >> +static int mtk_eint_irq_set_wake(struct irq_data *d, unsigned int on)
> > >> +{
> > >> +     struct mtk_pinctrl *pctl = irq_data_get_irq_chip_data(d);
> > >> +     int shift = d->hwirq & 0x1f;
> > >> +     int reg = d->hwirq >> 5;
> > >> +
> > >> +     if (on)
> > >> +             pctl->wake_mask[reg] |= BIT(shift);
> > >> +     else
> > >> +             pctl->wake_mask[reg] &= ~BIT(shift);
> > >> +
> > >> +     return 0;
> > >> +}
> > >
> > > Hi Maoguang,
> > >
> > > You changed from set_bit/clear_bit to this, but didn't add any locking.
> > > Since this is basic read/modify/write, is it OK to do it without
> > > locking?
> > 
> > I believe calling .irq_set_wake() concurrently with itself is
> > protected by irq_get_desc_buslock():
> > 
> >  int irq_set_irq_wake(unsigned int irq, unsigned int on)
> >  {
> >          unsigned long flags;
> >          struct irq_desc *desc = irq_get_desc_buslock(irq, &flags,
> > IRQ_GET_DESC_CHECK_GLOBAL);
> >          int ret = 0;
> > ...
> >                          ret = set_irq_wake_real(irq, on);
> > ...
> >          irq_put_desc_busunlock(desc, flags);
> >          return ret;
> >  }
> 
> Hi Dan,
> 
> You are right, irq_get_desc_buslock will acquire desc lock even when
> irq_chip didn't provide irq_bus_lock callback. So this should be OK.
> Sorry for the noise.
> 
> For this patch:
> 
> Acked-by: Yingjoe Chen <yingjoe.chen@xxxxxxxxxxxx>
> 
> Joe.C
> 


Acked-by: Hongzhou Yang <hongzhou.yang@xxxxxxxxxxxx>

Thanks.
Hongzhou


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/