[U-Boot] [PATCH v2 2/3] dm: add a command to list devices in a tree-like format

[Simon Glass]

Hi Masahiro,

On 20 November 2014 12:20, Masahiro Yamada <yamada.m at jp.panasonic.com> wrote:
> We are adding more and more drivers to driver model these days.
> Compared with the ad-hoc driver system, it seems pretty difficult to
> understand how drivers are working on driver model.  For ex.
>   - Which devices have been bound?
>   - Which devices have been probed?
>   - Which is the parent of this device?
> etc.
>
> I hope this tool will help us test/review driver model patches.
>
> Just hit "showdev" on the command line and it will list all the bound
> devices in a tree-like format with Class and Probed flag.

This looks very similar to the 'dm tree' command. Can we unify these?
Perhaps move the commands into common/cmd_dm.c? Then we can use the
CONFIG_CMD_DM option instead of a new one.

Also I think 'dm xxx' is better than things 'showdev'. The 'dm' prefix
can be used for all DM commands.

>
>   => showdev
>    Class       Probed   Name
>   ----------------------------------------
>    root        [ + ]    root_driver
>    demo        [   ]    |-- demo_shape_drv
>    demo        [   ]    |-- demo_simple_drv
>    demo        [   ]    |-- demo_shape_drv
>    demo        [   ]    |-- demo_simple_drv
>    demo        [   ]    |-- demo_shape_drv
>    test        [   ]    |-- test_drv
>    test        [   ]    |-- test_drv
>    test        [   ]    |-- test_drv
>    gpio        [   ]    |-- gpio_sandbox
>    serial      [   ]    |-- serial_sandbox
>    serial      [ + ]    |-- serial
>    demo        [   ]    |-- triangle
>    demo        [   ]    |-- square
>    demo        [   ]    |-- hexagon
>    gpio        [   ]    |-- gpios
>    i2c         [ + ]    |-- i2c at 0
>    i2c_eeprom  [ + ]    |   |-- eeprom at 2c
>    i2c_emul    [ + ]    |   |   \-- emul
>    i2c_generic [ + ]    |   \-- generic_59
>    spi         [   ]    |-- spi at 0
>    spi_emul    [   ]    |   \-- flash at 0
>    cros_ec     [ + ]    \-- cros-ec at 0
>
> Signed-off-by: Masahiro Yamada <yamada.m at jp.panasonic.com>
> ---
>
> Changes in v2:
>  - Fix the tree format
>
>  common/Makefile      |  1 +
>  common/cmd_showdev.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 71 insertions(+)
>  create mode 100644 common/cmd_showdev.c
>
> diff --git a/common/Makefile b/common/Makefile
> index 6cc4de8..c26c764 100644
> --- a/common/Makefile
> +++ b/common/Makefile
> @@ -84,6 +84,7 @@ obj-$(CONFIG_CMD_CPLBINFO) += cmd_cplbinfo.o
>  obj-$(CONFIG_DATAFLASH_MMC_SELECT) += cmd_dataflash_mmc_mux.o
>  obj-$(CONFIG_CMD_DATE) += cmd_date.o
>  obj-$(CONFIG_CMD_DEMO) += cmd_demo.o
> +obj-$(CONFIG_CMD_SHOWDEV) += cmd_showdev.o
>  obj-$(CONFIG_CMD_SOUND) += cmd_sound.o
>  ifdef CONFIG_4xx
>  obj-$(CONFIG_CMD_SETGETDCR) += cmd_dcr.o
> diff --git a/common/cmd_showdev.c b/common/cmd_showdev.c
> new file mode 100644
> index 0000000..f73bfba
> --- /dev/null
> +++ b/common/cmd_showdev.c
> @@ -0,0 +1,70 @@
> +/*
> + * Copyright (C) 2014 Panasonic Corporation
> + *   Author: Masahiro Yamada <yamada.m at jp.panasonic.com>
> + *
> + * SPDX-License-Identifier:    GPL-2.0+
> + */
> +
> +#include <common.h>
> +#include <linux/string.h>
> +#include <linux/list.h>
> +#include <dm/device.h>
> +#include <dm/uclass.h>
> +
> +DECLARE_GLOBAL_DATA_PTR;
> +
> +#define INDENT1 "    "
> +#define INDENT2 "|   "
> +#define INDENT3 "\\-- "
> +#define INDENT4 "|-- "

Is there really any value in these?

> +
> +static void show_devices(struct udevice *dev, int depth, int last_flag)
> +{
> +       int i, is_last;
> +       struct udevice *child;
> +       char class_name[12];
> +
> +       /* print the first 11 characters to not break the tree-format. */
> +       strlcpy(class_name, dev->uclass->uc_drv->name, sizeof(class_name));
> +       printf(" %-11s ", class_name);
> +
> +       printf("[ %c ]    ", dev->flags & DM_FLAG_ACTIVATED ? '+' : ' ');

This line could be combined with the above.

> +
> +       for (i = depth; i >= 0; i--) {
> +               is_last = (last_flag >> i) & 1;
> +               if (i) {
> +                       if (is_last)
> +                               printf(INDENT1);
> +                       else
> +                               printf(INDENT2);
> +               } else {
> +                       if (is_last)
> +                               printf(INDENT3);
> +                       else
> +                               printf(INDENT4);
> +               }
> +       }
> +
> +       printf("%s\n", dev->name);
> +
> +       list_for_each_entry(child, &dev->child_head, sibling_node) {
> +               is_last = list_is_last(&child->sibling_node, &dev->child_head);
> +               show_devices(child, depth + 1, (last_flag << 1) | is_last);
> +       }
> +}
> +
> +static int do_showdev(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
> +{
> +       printf(" Class       Probed   Name\n");

Remove the first space?

> +       printf("----------------------------------------\n");
> +
> +       show_devices(gd->dm_root, -1, 0);
> +
> +       return 0;
> +}
> +
> +U_BOOT_CMD(
> +       showdev, 1, 1, do_showdev,
> +       "show devices in a tree-like format.",
> +       ""
> +);
> --
> 1.9.1
>

Regards,
Simon