[bug report] ASoC: mchp-spdifrx: add driver for SPDIF RX

[Dan Carpenter]

On Thu, Dec 03, 2020 at 03:31:33PM +0000, Codrin.Ciubotariu at microchip.com wrote:
> On 03.12.2020 16:58, Dan Carpenter wrote:
> > Hello Codrin Ciubotariu,
> > 
> > The patch ef265c55c1ac: "ASoC: mchp-spdifrx: add driver for SPDIF RX"
> > from Oct 2, 2020, leads to the following static checker warning:
> > 
> >          sound/soc/atmel/mchp-spdifrx.c:468 mchp_spdifrx_hw_params()
> >          warn: 'dev->gclk' not released on lines: 468.
> > 
> > sound/soc/atmel/mchp-spdifrx.c
> >     442                          params_format(params));
> >     443                  return -EINVAL;
> >     444          }
> >     445
> >     446          if (dev->gclk_enabled) {
> >     447                  clk_disable_unprepare(dev->gclk);
> >     448                  dev->gclk_enabled = 0;
> >     449          }
> >     450          ret = clk_set_min_rate(dev->gclk, params_rate(params) *
> >     451                                            SPDIFRX_GCLK_RATIO_MIN + 1);
> >     452          if (ret) {
> >     453                  dev_err(dev->dev,
> >     454                          "unable to set gclk min rate: rate %u * ratio %u + 1\n",
> >     455                          params_rate(params), SPDIFRX_GCLK_RATIO_MIN);
> >     456                  return ret;
> >     457          }
> >     458          ret = clk_prepare_enable(dev->gclk);
> >                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > 
> >     459          if (ret) {
> >     460                  dev_err(dev->dev, "unable to enable gclk: %d\n", ret);
> >     461                  return ret;
> >     462          }
> >     463          dev->gclk_enabled = 1;
> >     464
> >     465          dev_dbg(dev->dev, "GCLK range min set to %d\n",
> >     466                  params_rate(params) * SPDIFRX_GCLK_RATIO_MIN + 1);
> >     467
> >     468          return regmap_write(dev->regmap, SPDIFRX_MR, mr);
> >                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > Smatch is complaining that if the regmap_write() fails then we should
> > disable and unprepare the "dev->gclk".
> > 
> >     469  }
> > 
> 
> Thanks for reporting this Dan. hw_free() callback is still called if 
> hw_params() fails, which will unprepare gclk, but I guess it doesn't 
> hurt to add what you suggested.

It might hurt if it leads to a double free...  Just leave it as is.
This is a new warning message for Smatch and I'm still working out the
kinks.

regards,
dan carpenter