[U-Boot] [PATCH v2] board/p1010rdb: add pin mux and sdhc support in any boot

[Andy Fleming]

On Sun, Jun 16, 2013 at 9:32 PM, Shengzhou Liu
<Shengzhou.Liu at freescale.com>wrote:

> SDHC pins are multiplexed with IFC and ULPI interfaces.
> This patch intends to enable SDHC function in case of
> NOR/NAND/SPI boot aside from SD boot.
>
> If "esdhc" is configured in hwconfig, u-boot will configure
> multiplexing pins from default IFC to SDHC at runtime to
> enable SD function. And add minimal necessary mux command for
> ifc/sdhc/ulpi to conveniently configure multiplexing pins
> without reboot or updating u-boot.
>
> Signed-off-by: Shengzhou Liu <Shengzhou.Liu at freescale.com>
> ---
> v2: updated description.
>
>  board/freescale/p1010rdb/p1010rdb.c | 128
> +++++++++++++++++++++++++++++++++---
>  include/configs/P1010RDB.h          |  11 ++--
>  2 files changed, 125 insertions(+), 14 deletions(-)
>
> diff --git a/board/freescale/p1010rdb/p1010rdb.c
> b/board/freescale/p1010rdb/p1010rdb.c
> index 0c30d76..5a2f1f0 100644
> --- a/board/freescale/p1010rdb/p1010rdb.c
> +++ b/board/freescale/p1010rdb/p1010rdb.c
>


> +static int pin_mux_cmd(cmd_tbl_t *cmdtp, int flag, int argc,
> +                                       char * const argv[])
> +{
> +       if (argc < 2)
> +               return CMD_RET_USAGE;
> +       if (strcmp(argv[1], "ifc") == 0)
> +               config_pin_mux(MUX_TYPE_IFC);
> +       else if (strcmp(argv[1], "sdhc") == 0)
> +               config_pin_mux(MUX_TYPE_SDHC);
> +       else if (strcmp(argv[1], "ulpi") == 0)
> +               config_pin_mux(MUX_TYPE_ULPI);
> +       else
> +               return CMD_RET_USAGE;
> +       return 0;
> +}
> +
> +U_BOOT_CMD(
> +       mux, 2, 0, pin_mux_cmd,
> +       "configure multiplexing pin for IFC/SDHC/ULPI buses",
> +       "bus_type[ifc/sdhc/ulpi] (e.g. mux sdhc)"
>


This command name is very generic, but the command is highly-specific to
this board. Ideally, you'd come up with code that could be reused by other
boards that have similar issues. It should be fairly straightforward to
implement a version of this code which allowed arbitrary pin muxing code to
register with a name. It would require some discussion on the list. If
you're not willing to do that, at least rename the command so it's clear it
is just for this board.


Andy