[PATCH] spi: omap3_spi: Fix speed and mode selection

[Miquel Raynal]

Hi Vignesh,

Vignesh Raghavendra <vigneshr at ti.com> wrote on Tue, 1 Dec 2020 15:45:27
+0530:

> +Miquel,
> 
> On 11/29/20 12:53 PM, Vignesh Raghavendra wrote:
> > McSPI IP provides per CS specific speed and mode selection. Therefore it
> > is possible to apply these settings only after CS is known. But
> > set_speed and set_mode can be called without bus being claimed, this
> > would lead driver to set up wrong CS (or previously used CS).
> > 
> > Fix this by apply set_speed and set_mode only if bus is already claimed.

I was experiencing the following issue: any first sf probe 1:1 call
would fail while any other attempt would work.

This patch fixes it.

Tested-by: Miquel Raynal <miquel.raynal at bootlin.com>

> > 
> > Signed-off-by: Vignesh Raghavendra <vigneshr at ti.com>
> > ---
> >  drivers/spi/omap3_spi.c | 17 ++++++++++++++---
> >  1 file changed, 14 insertions(+), 3 deletions(-)
> > 
> > diff --git a/drivers/spi/omap3_spi.c b/drivers/spi/omap3_spi.c
> > index 56cb217486..fe73362945 100644
> > --- a/drivers/spi/omap3_spi.c
> > +++ b/drivers/spi/omap3_spi.c
> > @@ -37,6 +37,8 @@ struct omap3_spi_priv {
> >  	unsigned int mode;
> >  	unsigned int wordlen;
> >  	unsigned int pin_dir:1;
> > +
> > +	bool bus_claimed;
> >  };
> >  
> >  static void omap3_spi_write_chconf(struct omap3_spi_priv *priv, int val)
> > @@ -372,6 +374,8 @@ static void _omap3_spi_claim_bus(struct omap3_spi_priv *priv)
> >  	conf |= OMAP3_MCSPI_MODULCTRL_SINGLE;
> >  
> >  	writel(conf, &priv->regs->modulctrl);
> > +
> > +	priv->bus_claimed = true;
> >  }
> >  
> >  static int omap3_spi_claim_bus(struct udevice *dev)
> > @@ -381,9 +385,12 @@ static int omap3_spi_claim_bus(struct udevice *dev)
> >  	struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
> >  
> >  	priv->cs = slave_plat->cs;
> > -	priv->freq = slave_plat->max_hz;
> > +	if (!priv->freq)
> > +		priv->freq = slave_plat->max_hz;
> >  
> >  	_omap3_spi_claim_bus(priv);
> > +	_omap3_spi_set_speed(priv);
> > +	_omap3_spi_set_mode(priv);
> >  
> >  	return 0;
> >  }
> > @@ -395,6 +402,8 @@ static int omap3_spi_release_bus(struct udevice *dev)
> >  
> >  	writel(OMAP3_MCSPI_MODULCTRL_MS, &priv->regs->modulctrl);
> >  
> > +	priv->bus_claimed = false;
> > +
> >  	return 0;
> >  }
> >  
> > @@ -440,7 +449,8 @@ static int omap3_spi_set_speed(struct udevice *dev, unsigned int speed)
> >  	struct omap3_spi_priv *priv = dev_get_priv(dev);
> >  
> >  	priv->freq = speed;
> > -	_omap3_spi_set_speed(priv);
> > +	if (priv->bus_claimed)
> > +		_omap3_spi_set_speed(priv);
> >  
> >  	return 0;
> >  }
> > @@ -451,7 +461,8 @@ static int omap3_spi_set_mode(struct udevice *dev, uint mode)
> >  
> >  	priv->mode = mode;
> >  
> > -	_omap3_spi_set_mode(priv);
> > +	if (priv->bus_claimed)
> > +		_omap3_spi_set_mode(priv);
> >  
> >  	return 0;
> >  }


Thanks,
Miquèl