RE: [EXT] Re: [v4 2/2] clk: ls1028a: Add clock driver for Display output interface

[Wen He]

> -----Original Message-----
> From: Stephen Boyd <sboyd@xxxxxxxxxx>
> Sent: 2019å9æ19æ 1:01
> To: devicetree@xxxxxxxxxxxxxxx; linux-clk@xxxxxxxxxxxxxxx;
> linux-devel@xxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Mark Rutland
> <mark.rutland@xxxxxxx>; Michael Turquette <mturquette@xxxxxxxxxxxx>;
> Rob Herring <robh+dt@xxxxxxxxxx>; Wen He <wen.he_1@xxxxxxx>
> Cc: Leo Li <leoyang.li@xxxxxxx>; liviu.dudau@xxxxxxx
> Subject: RE: [EXT] Re: [v4 2/2] clk: ls1028a: Add clock driver for Display output
> interface
> 
> 
> Quoting Wen He (2019-09-18 02:20:26)
> > > -----Original Message-----
> > > From: Stephen Boyd <sboyd@xxxxxxxxxx> Quoting Wen He (2019-08-29
> > > 03:59:19)
> > > > diff --git a/drivers/clk/clk-plldig.c b/drivers/clk/clk-plldig.c
> > > > new file mode 100644 index 000000000000..d3239bcf59de
> > > > --- /dev/null
> > > > +++ b/drivers/clk/clk-plldig.c
> > > > @@ -0,0 +1,298 @@
> [...]
> >
> > >
> > > > +
> > > > +/* Maximum of the divider */
> > > > +#define MAX_RFDPHI1          63
> > > > +
> > > > +/* Best value of multiplication factor divider */
> > > > +#define PLLDIG_DEFAULE_MULT         44
> > > > +
> > > > +/*
> > > > + * Clock configuration relationship between the PHI1
> > > > +frequency(fpll_phi) and
> > > > + * the output frequency of the PLL is determined by the PLLDV,
> > > > +according to
> > > > + * the following equation:
> > > > + * fpll_phi = (pll_ref * mfd) / div_rfdphi1  */ struct
> > > > +plldig_phi1_param {
> > > > +       unsigned long rate;
> > > > +       unsigned int rfdphi1;
> > > > +       unsigned int mfd;
> > > > +};
> > > > +
> > > > +enum plldig_phi1_freq_range {
> > > > +       PHI1_MIN        = 27000000U,
> > > > +       PHI1_MAX        = 600000000U
> > > > +};
> > >
> > > Please just inline these values in the one place they're used.
> > >
> > > > +
> > > > +struct clk_plldig {
> > > > +       struct clk_hw hw;
> > > > +       void __iomem *regs;
> > > > +       struct device *dev;
> > >
> > > Please remove this, it is unused.
> >
> > It is used for probe.
> 
> Use a local variable and don't store it away forever in the struct.
> 

Understand, will remove it.

> > >
> > > > +
> > > > +       val = readl(data->regs + PLLDIG_REG_PLLDV);
> > > > +       val = phi1_param.mfd;
> > > > +       rfdphi1 = phi1_param.rfdphi1;
> > > > +       val |= rfdphi1;
> > > > +
> > > > +       writel(val, data->regs + PLLDIG_REG_PLLDV);
> > > > +
> > > > +       /* delay 200us make sure that old lock state is cleared */
> > > > +       udelay(200);
> > > > +
> > > > +       /* Wait until PLL is locked or timeout (maximum 1000 usecs) */
> > > > +       ret = readl_poll_timeout_atomic(data->regs +
> > > > + PLLDIG_REG_PLLSR,
> > > cond,
> > > > +                                       cond &
> PLLDIG_LOCK_MASK,
> > > 0,
> > > > +                                       USEC_PER_MSEC);
> > > > +
> > > > +       return ret;
> > >
> > > Just return readl_poll_timeout_atomic(...) here.
> >
> > Maybe use below code will to best describes.
> >
> > If (ret)
> >         return -ETIMEOUT;
> >
> > return 0;
> 
> No, just return readl_poll_timeout_atomic().

Understand, I will send next version patch for this.

Thanks && Best Regards,
Wen