[U-Boot] [PATCH v2 04/29] stdio: Pass device pointer to stdio methods

[Marek Vasut]

On Wednesday, July 09, 2014 at 05:37:54 AM, Simon Glass wrote:
> At present stdio device functions do not get any clue as to which stdio
> device is being acted on. Some implementations go to great lengths to work
> around this, such as defining a whole separate set of functions for each
> possible device.
> 
> For driver model we need to associate a stdio_dev with a device. It doesn't
> seem possible to continue with this work-around approach.
> 
> Instead, add a stdio_dev pointer to each of the stdio member functions.
> 
> Note: The serial drivers have the same problem, but it is not strictly
> necessary to fix that to get driver model running. Also, if we convert
> serial over to driver model the problem will go away.
> 
> Code size increases by 244 bytes for Thumb2 and 428 for PowerPC.
> 
> 22: stdio: Pass device pointer to stdio methods
>        arm: (for 2/2 boards)  all +244.0  bss -4.0  text +248.0
>    powerpc: (for 1/1 boards)  all +428.0  text +428.0
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>
> Acked-by: Marek Vasut <marex at denx.de>

[...]

> diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
> index fd61a5e..803d850 100644
> --- a/drivers/serial/serial.c
> +++ b/drivers/serial/serial.c
> @@ -254,6 +254,48 @@ void serial_initialize(void)
>  	serial_assign(default_serial_console()->name);
>  }
> 
> +int serial_stub_start(struct stdio_dev *sdev)
> +{
> +	struct serial_device *dev = sdev->priv;

Are you sure this pointer derefference won't blow if $sdev is ever NULL? Can 
$sdev be NULL (in some early stage for example) ?

> +	return dev->start();
> +}

Reviewed-by: Marek Vasut <marex at denx.de>

I really like where this is going.

Best regards,
Marek Vasut