RE: [PATCH 3/5] spi: s3c64xx: support custom value of internal clock divider

["Chanho Park" <chanho61.park@samsung.com>]

> Subject: Re: [PATCH 3/5] spi: s3c64xx: support custom value of internal
> clock divider
> 
> On 27/06/2022 08:47, Chanho Park wrote:
> > Modern exynos SoCs such as Exynos Auto v9 has different internal clock
> > divider, for example "4". To support this internal value, this adds
> > clk_div of the s3c64xx_spi_port_config and use it if it is specified.
> > Otherwise, use "2" which is the previous default value.
> >
> > Signed-off-by: Chanho Park <chanho61.park@samsung.com>
> > ---
> >  drivers/spi/spi-s3c64xx.c | 23 +++++++++++++++--------
> >  1 file changed, 15 insertions(+), 8 deletions(-)
> >
> > diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
> > index e17c74c0d7de..dd5fc8570bce 100644
> > --- a/drivers/spi/spi-s3c64xx.c
> > +++ b/drivers/spi/spi-s3c64xx.c
> > @@ -131,6 +131,7 @@ struct s3c64xx_spi_dma_data {
> >   * @fifo_lvl_mask: Bit-mask for {TX|RX}_FIFO_LVL bits in SPI_STATUS
> register.
> >   * @rx_lvl_offset: Bit offset of RX_FIFO_LVL bits in SPI_STATUS regiter.
> >   * @tx_st_done: Bit offset of TX_DONE bit in SPI_STATUS regiter.
> > + * @clk_div: Internal clock divider, if not specified, use 2 as the
> default.
> >   * @quirks: Bitmask of known quirks
> >   * @high_speed: True, if the controller supports HIGH_SPEED_EN bit.
> >   * @clk_from_cmu: True, if the controller does not include a clock
> > mux and @@ -148,6 +149,7 @@ struct s3c64xx_spi_port_config {
> >  	int	rx_lvl_offset;
> >  	int	tx_st_done;
> >  	int	quirks;
> > +	int	clk_div;
> >  	bool	high_speed;
> >  	bool	clk_from_cmu;
> >  	bool	clk_ioclk;
> > @@ -620,6 +622,7 @@ static int s3c64xx_spi_config(struct
> s3c64xx_spi_driver_data *sdd)
> >  	void __iomem *regs = sdd->regs;
> >  	int ret;
> >  	u32 val;
> > +	u32 div = sdd->port_conf->clk_div ? sdd->port_conf->clk_div : 2;
> 
> I would prefer to explicitly set '2' as clk_div for existing variants.
> Such assignments in the code are usually trickier to find/read.

Make sense. It can be more clear what value is using.
I'll apply it next patchset.

Best Regards,
Chanho Park