linux-kernel - RE: [PATCH v3 2/3] pinctrl: intel: refine ->irq_set

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Message-ID: <DM6PR11MB2779664C590484A1601A93298C5BA@DM6PR11MB2779.namprd11.prod.outlook.com>
Date:   Thu, 15 Jun 2023 11:08:38 +0000
From:   "Jadav, Raag" <raag.jadav@...el.com>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        "mika.westerberg@...ux.intel.com" <mika.westerberg@...ux.intel.com>
CC:     "linus.walleij@...aro.org" <linus.walleij@...aro.org>,
        "linux-gpio@...r.kernel.org" <linux-gpio@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "Sangannavar, Mallikarjunappa" 
        <mallikarjunappa.sangannavar@...el.com>,
        "N, Pandith" <pandith.n@...el.com>
Subject: RE: [PATCH v3 2/3] pinctrl: intel: refine ->irq_set_type() hook

> On Thu, Jun 15, 2023 at 12:55:17PM +0300,
> mika.westerberg@...ux.intel.com wrote:
> > On Thu, Jun 15, 2023 at 09:48:12AM +0000, Jadav, Raag wrote:
> > > > On Tue, Jun 13, 2023 at 02:20:53PM +0530, Raag Jadav wrote:
> 
> ...
> 
> > > > Looking at this I realized that entire temporary variable
> > > > assignments can be done outside of spin lock. You probably would
> > > > need another one for keeping rxinv value.
> > >
> > > Something like this?
> 
> Almost, see below.
> 
> > >         u32 value, rxevcfg;
> > >         u32 rxinv = 0;
> 
> No assignment here.
> 
>          u32 rxinv, rxevcfg;
>          u32 value;
> 
> > >         if ((type & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
> > >                 rxevcfg = PADCFG0_RXEVCFG_EDGE_BOTH;
> > >         } else if (type & IRQ_TYPE_EDGE_FALLING) {
> > >                 rxevcfg = PADCFG0_RXEVCFG_EDGE;
> > >         } else if (type & IRQ_TYPE_EDGE_RISING) {
> > >                 rxevcfg = PADCFG0_RXEVCFG_EDGE;
> > >         } else if (type & IRQ_TYPE_LEVEL_MASK) {
> > >                 rxevcfg = PADCFG0_RXEVCFG_LEVEL;
> > >         } else {
> > >                 rxevcfg = PADCFG0_RXEVCFG_DISABLED;
> > >         }
> 
> Now, if it's fully included in the diff (even with --patience parameter), then
> you may drop {}.
> 
> > >         if (type == IRQ_TYPE_EDGE_FALLING || type ==
> IRQ_TYPE_LEVEL_LOW)
> > >                 rxinv = PADCFG0_RXINV;
> 
> 		else
> 			rxinv = 0;
> 
> > >         raw_spin_lock_irqsave(&pctrl->lock, flags);
> > >
> > >         intel_gpio_set_gpio_mode(reg);
> > >
> > >         value = readl(reg);
> > >
> > >         value &= ~(PADCFG0_RXEVCFG_MASK | PADCFG0_RXINV);
> > >         value |= rxinv;
> > >         value |= rxevcfg << PADCFG0_RXEVCFG_SHIFT;
> 
> And I would rewrite these to the standard patterns:
> 
>          value = (value & ~PADCFG0_RXINV) | rxinv;
>          value = (value & ~PADCFG0_RXEVCFG_MASK) | (rxevcfg <<
> PADCFG0_RXEVCFG_SHIFT);
> 
> And looking at this, perhaps do shift also outside the lock:
> 
>          } else {
>                  rxevcfg = PADCFG0_RXEVCFG_DISABLED;
>          }
>          rxevcfg <<= PADCFG0_RXEVCFG_SHIFT;
> 
> But, taking into account scope of the _RXEVCFG_*, I would add shift directly
> to the definitions and kill that SHIFT entirely:
> 
> #define PADCFG0_RXEVCFG_LEVEL           (0 << 25)
> #define PADCFG0_RXEVCFG_EDGE            (1 << 25)
> #define PADCFG0_RXEVCFG_DISABLED        (2 << 25)
> #define PADCFG0_RXEVCFG_EDGE_BOTH       (3 << 25)
> 
> 	 ...
> 
>          value = (value & ~PADCFG0_RXINV) | rxinv;
>          value = (value & ~PADCFG0_RXEVCFG_MASK) | rxevcfg;
> 
> Try that one and look if it looks better. It might even save bytes after all.

Should I add all of this in original patch or send this as a separate patch
on top this series?