[U-Boot] [PATCH] dm: allow setting driver_data before/during bind

[Simon Glass]

Hi Stephen,

On 28 April 2016 at 17:08, Stephen Warren <swarren at wwwdotorg.org> wrote:
> From: Stephen Warren <swarren at nvidia.com>
>
> This will allow a driver's bind function to use the driver data. One
> example is the Tegra186 GPIO driver, which instantiates child devices
> for each of its GPIO ports, yet supports two different HW instances each
> with a different set of ports, and identified by the udevice_id .data
> field.
>
> Signed-off-by: Stephen Warren <swarren at nvidia.com>
> ---
>  drivers/core/device.c            | 7 ++++---
>  drivers/core/lists.c             | 6 +++---
>  drivers/gpio/dwapb_gpio.c        | 2 +-
>  drivers/gpio/s5p_gpio.c          | 2 +-
>  drivers/gpio/sunxi_gpio.c        | 2 +-
>  drivers/gpio/tegra_gpio.c        | 2 +-
>  drivers/mtd/spi/sandbox.c        | 2 +-
>  drivers/net/mvpp2.c              | 3 ++-
>  drivers/pci/pci-uclass.c         | 5 ++---
>  drivers/power/pmic/pmic-uclass.c | 2 +-
>  drivers/usb/host/usb-uclass.c    | 5 ++---
>  include/dm/device-internal.h     | 5 +++--
>  12 files changed, 22 insertions(+), 21 deletions(-)

I'm not sure this extra parameter carries its weight:

- most callers just pass 0
- the field is supposed to be set up by device tree and probing tables, not code
- bind() methods should not care about the driver data (they are not
allowed to touch hardware), so setting it later is fine
- you can already pass platform data to the driver which is the
preferred communication method from a parent to its children

Also it's not clear from your Tegra 186 GPIO patch where you are using this.

Regards,
Simon