[U-Boot] [PATCH] imx: mx25: Remove SION bit in all pin-mux

[Fabio Estevam]

Hi Michael,

On Wed, Jan 24, 2018 at 12:56 PM, Michael Trimarchi
<michael at amarulasolutions.com> wrote:
> SION bit should be used in the situation that we need
> to read back the value of a pin and should be set by
> default. This can generate any kind of random malfunction
> as described in this thread.
>
> According to this thread:
> https://www.spinics.net/lists/linux-usb/msg162574.html
>
> We consider this an early bug so all the boards running imx25
> with a minimimal set of functionalities can be affected.
>
> As reported by this application note:
> https://www.nxp.com/docs/en/application-note/AN5078.pdf
>
> The software input on (SION) bit is an option to force an input
> path to be active regardless of the value driven by the
> corresponding module. It is used when the nature direction
> of a pin depending on selected alternative function is an output,
> but it is needed to read the real logic value on a pin.
>
> The SION bit can be used in:
> • Loopback: the module of a selected alternative function drives
> the pad and also receives the pad value as an input
> • GPIO capture: the module of a selected alternative function
> drives the pin and the value is captured by the GPIO
>
> Signed-off-by: Michael Trimarchi <michael at amarulasolutions.com>
> ---
> Refer-to:
>         MX25 USB timeout on ID 0951:1665 Kingston Technology Digital
>         DataTraveler SE9 64GB

Glad you found a fix for the issue!


> ---
>  arch/arm/include/asm/arch-mx25/iomux-mx25.h | 680 ++++++++++++++--------------
>  1 file changed, 340 insertions(+), 340 deletions(-)
>
> diff --git a/arch/arm/include/asm/arch-mx25/iomux-mx25.h b/arch/arm/include/asm/arch-mx25/iomux-mx25.h
> index 5b2863e..2fcaf60 100644
> --- a/arch/arm/include/asm/arch-mx25/iomux-mx25.h
> +++ b/arch/arm/include/asm/arch-mx25/iomux-mx25.h
> @@ -30,481 +30,481 @@
>
>  /*                                                         PAD    MUX    ALT INPSE PATH PADCTRL */
>  enum {
> -       MX25_PAD_A10__A10                       = IOMUX_PAD(0x000, 0x008, 0x00, 0, 0, NO_PAD_CTRL),
> -       MX25_PAD_A10__GPIO_4_0                  = IOMUX_PAD(0x000, 0x008, 0x05, 0, 0, NO_PAD_CTRL),
> +       MX25_PAD_A10__A10                       = IOMUX_PAD(0x000, 0x008, 0, 0, 0, NO_PAD_CTRL),
> +       MX25_PAD_A10__GPIO_4_0                  = IOMUX_PAD(0x000, 0x008, 5, 0, 0, NO_PAD_CTRL),

In many places in this patch you are only changing things like 0x00
--> 0 or 0x05--> 5, which just makes it harder to review.

Please send a new version that only removes the SION bit.