[U-Boot] [PATCH 1/2] spi: spi-mxc: implement clk control for ECSPI to fix SPI_MODE_3

[Markus Niebel]

Hello,

> Von: Jagan Teki [mailto:jagannadh.teki at gmail.com]
> Gesendet: Sonntag, 16. Februar 2014 17:58
> An: Markus Niebel
> Cc: u-boot at lists.denx.de; Markus Niebel
> Betreff: Re: [U-Boot] [PATCH 1/2] spi: spi-mxc: implement clk control
> for ECSPI to fix SPI_MODE_3
> 
> On Mon, Feb 10, 2014 at 1:57 PM, Markus Niebel <list-09_u-boot at tqsc.de>
> wrote:
> > From: Markus Niebel <Markus.Niebel at tqs.de>
> >
> > SPI_MODE_3 requires clk high when inactive. The SCLK_CTL
> > field of the config reg was not configured. Provide defines
> > for missing fields in the ECSPI config reg and use them
> > for SPI_CPOL
> >
> > Signed-off-by: Markus Niebel <Markus.Niebel at tqs.de>
> > ---
> >  arch/arm/include/asm/arch-mx5/imx-regs.h |    9 ++++++---
> >  arch/arm/include/asm/arch-mx6/imx-regs.h |    9 ++++++---
> >  drivers/spi/mxc_spi.c                    |    9 +++++++--
> >  3 files changed, 19 insertions(+), 8 deletions(-)
> >
> > diff --git a/arch/arm/include/asm/arch-mx5/imx-regs.h
> b/arch/arm/include/asm/arch-mx5/imx-regs.h
> > index 4955ccf..32386d3 100644
> > --- a/arch/arm/include/asm/arch-mx5/imx-regs.h
> > +++ b/arch/arm/include/asm/arch-mx5/imx-regs.h
> > @@ -230,9 +230,12 @@
> >  #define MXC_CSPICTRL_CHAN      18
> >
> >  /* Bit position inside CON register to be associated with SS */
> > -#define MXC_CSPICON_POL                4
> > -#define MXC_CSPICON_PHA                0
> > -#define MXC_CSPICON_SSPOL      12
> > +#define MXC_CSPICON_PHA                0  /* SCLK phase control */
> > +#define MXC_CSPICON_POL                4  /* SCLK polarity */
> > +#define MXC_CSPICON_SSCTL      8  /* SS wave form select */
> > +#define MXC_CSPICON_SSPOL      12 /* SS polarity */
> > +#define MXC_CSPICON_DCTL       16 /* inactive state of MOSI */
> > +#define MXC_CSPICON_CTL                20 /* inactive state of SCLK
> */
> >  #define MXC_SPI_BASE_ADDRESSES \
> >         CSPI1_BASE_ADDR, \
> >         CSPI2_BASE_ADDR, \
> > diff --git a/arch/arm/include/asm/arch-mx6/imx-regs.h
> b/arch/arm/include/asm/arch-mx6/imx-regs.h
> > index f2ad6e9..79842bf 100644
> > --- a/arch/arm/include/asm/arch-mx6/imx-regs.h
> > +++ b/arch/arm/include/asm/arch-mx6/imx-regs.h
> > @@ -405,9 +405,12 @@ struct cspi_regs {
> >  #define MXC_CSPICTRL_CHAN      18
> >
> >  /* Bit position inside CON register to be associated with SS */
> > -#define MXC_CSPICON_POL                4
> > -#define MXC_CSPICON_PHA                0
> > -#define MXC_CSPICON_SSPOL      12
> > +#define MXC_CSPICON_PHA                0  /* SCLK phase control */
> > +#define MXC_CSPICON_POL                4  /* SCLK polarity */
> > +#define MXC_CSPICON_SSCTL      8  /* SS wave form select */
> > +#define MXC_CSPICON_SSPOL      12 /* SS polarity */
> > +#define MXC_CSPICON_DCTL       16 /* inactive state of MOSI */
> > +#define MXC_CSPICON_CTL                20 /* inactive state of SCLK
> */
> 
> Few of these macros not used in this patch, do you really require in
> this change.?

No, not really - but I saw this for other register related defines, too that
bits that are actually not be used are defined - just for completeness

If this is a coding style problem, I will send the patches without the unused
Bit defines again

> 
> >  #ifdef CONFIG_MX6SL
> >  #define MXC_SPI_BASE_ADDRESSES \
> >         ECSPI1_BASE_ADDR, \
> > diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c
> > index 95dd03f..f3f029d 100644
> > --- a/drivers/spi/mxc_spi.c
> > +++ b/drivers/spi/mxc_spi.c
> > @@ -115,7 +115,8 @@ static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs,
> unsigned int cs,
> >  {
> >         u32 clk_src = mxc_get_clock(MXC_CSPI_CLK);
> >         s32 reg_ctrl, reg_config;
> > -       u32 ss_pol = 0, sclkpol = 0, sclkpha = 0, pre_div = 0,
> post_div = 0;
> > +       u32 ss_pol = 0, sclkpol = 0, sclkpha = 0, sclkctl = 0;
> > +       u32 pre_div = 0, post_div = 0;
> >         struct cspi_regs *regs = (struct cspi_regs *)mxcs->base;
> >
> >         if (max_hz == 0) {
> > @@ -164,8 +165,10 @@ static s32 spi_cfg_mxc(struct mxc_spi_slave
> *mxcs, unsigned int cs,
> >         if (mode & SPI_CS_HIGH)
> >                 ss_pol = 1;
> >
> > -       if (mode & SPI_CPOL)
> > +       if (mode & SPI_CPOL) {
> >                 sclkpol = 1;
> > +               sclkctl = 1;
> > +       }
> >
> >         if (mode & SPI_CPHA)
> >                 sclkpha = 1;
> > @@ -180,6 +183,8 @@ static s32 spi_cfg_mxc(struct mxc_spi_slave *mxcs,
> unsigned int cs,
> >                 (ss_pol << (cs + MXC_CSPICON_SSPOL));
> >         reg_config = (reg_config & ~(1 << (cs + MXC_CSPICON_POL))) |
> >                 (sclkpol << (cs + MXC_CSPICON_POL));
> > +       reg_config = (reg_config & ~(1 << (cs + MXC_CSPICON_CTL))) |
> > +               (sclkctl << (cs + MXC_CSPICON_CTL));
> >         reg_config = (reg_config & ~(1 << (cs + MXC_CSPICON_PHA))) |
> >                 (sclkpha << (cs + MXC_CSPICON_PHA));
> >
> > --
> > 1.7.9.5
> >
> > _______________________________________________
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> > U-Boot at lists.denx.de
> > http://lists.denx.de/mailman/listinfo/u-boot
> 
> 
> thanks!
> --
> Jagan.
Markus