Re: [PATCH v2 01/11] media: ccs-pll: Start OP pre-PLL multiplier search from correct value

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

On Tue, Apr 22, 2025 at 11:43:18AM +0000, Sakari Ailus wrote:
> On Mon, Apr 21, 2025 at 10:50:04PM +0300, Laurent Pinchart wrote:
> > On Thu, Apr 17, 2025 at 09:53:44AM +0300, Sakari Ailus wrote:
> > > The ccs_pll_calculate() function does a search over possible PLL
> > > configurations to find the "best" one. If the sensor did not support odd
> > 
> > s/did not/does not/
> > 
> > > pre-PLL divisors and the minimum value (with constraints) wasn't 1, other
> > 
> > s/wasn't/isn't/
> > 
> > > even values could have errorneously searched (and selected) for the
> > 
> > s/could have errorneously searched/
> > s/could be erroneously searched/
> > 
> > Do you mean "other odd values" ?
> 
> Odd values that aren't 1.

You wrote ", other even values could ...". I think s/even/odd/ is what
you meant.

> > > pre-PLL divisor. Fix this.
> > > 
> > > Fixes: 415ddd993978 ("media: ccs-pll: Split limits and PLL configuration into front and back parts")
> > > Cc: stable@vger.kernel.org
> > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> > > ---
> > >  drivers/media/i2c/ccs-pll.c | 2 ++
> > >  1 file changed, 2 insertions(+)
> > > 
> > > diff --git a/drivers/media/i2c/ccs-pll.c b/drivers/media/i2c/ccs-pll.c
> > > index 34ccda666524..e516ed23e899 100644
> > > --- a/drivers/media/i2c/ccs-pll.c
> > > +++ b/drivers/media/i2c/ccs-pll.c
> > > @@ -815,6 +815,8 @@ int ccs_pll_calculate(struct device *dev, const struct ccs_pll_limits *lim,
> > >  			      one_or_more(
> > >  				      DIV_ROUND_UP(op_lim_fr->max_pll_op_clk_freq_hz,
> > >  						   pll->ext_clk_freq_hz))));
> > > +	if (!(pll->flags & CCS_PLL_FLAG_EXT_IP_PLL_DIVIDER))
> > > +		min_op_pre_pll_clk_div = clk_div_even(min_op_pre_pll_clk_div);
> > >  	dev_dbg(dev, "pll_op check: min / max op_pre_pll_clk_div: %u / %u\n",
> > >  		min_op_pre_pll_clk_div, max_op_pre_pll_clk_div);
> > >  
> > 
> > Is my understanding correct that the problem can only occur during the
> > first iteration of the loop just below ? If so, with the commit message
> > fixed,
> 
> Correct.
> 
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> > 
> > If not, there's something I don't get :-)
> 
> :-)

-- 
Regards,

Laurent Pinchart