[U-Boot] [PATCH] usb: ums: wait for usb cable connection before enter ums mode

[Przemyslaw Marczak]

Hello everyone,

On 01/07/2014 03:08 PM, Przemyslaw Marczak wrote:
> Before this change ums mode can not be entered when device
> was using the same usb port for usb/uart communication.
> Switching USB cable from UART to USB always causes ums exit.
>
> Signed-off-by: Przemyslaw Marczak <p.marczak at samsung.com>
>
> ---
>   common/cmd_usb_mass_storage.c |   24 ++++++++++++++++++++++++
>   include/usb_mass_storage.h    |    3 +++
>   2 files changed, 27 insertions(+)
>
> diff --git a/common/cmd_usb_mass_storage.c b/common/cmd_usb_mass_storage.c
> index 99487f4..5f557d5 100644
> --- a/common/cmd_usb_mass_storage.c
> +++ b/common/cmd_usb_mass_storage.c
> @@ -42,6 +42,30 @@ int do_usb_mass_storage(cmd_tbl_t *cmdtp, int flag,
>
>   	g_dnl_register("ums");
>
> +	/* Timeout unit: seconds */
> +	int cable_ready_timeout = UMS_CABLE_READY_TIMEOUT;
> +
> +	if (!usb_cable_connected()) {
> +		puts("Please connect USB cable.\n");
> +
> +		while (!usb_cable_connected()) {
> +			if (ctrlc()) {
> +				puts("\rCTRL+C - Operation aborted.\n");
> +				goto exit;
> +			}
> +			if (!cable_ready_timeout) {
> +				puts("\rUSB cable not detected.\n" \
> +				     "Command exit.\n");
> +				goto exit;
> +			}
> +
> +			printf("\rAuto exit in: %.2d s.", cable_ready_timeout);
> +			mdelay(1000);
> +			cable_ready_timeout--;
> +		}
> +		puts("\r\n");
> +	}
> +
>   	while (1) {
>   		usb_gadget_handle_interrupts();
>
> diff --git a/include/usb_mass_storage.h b/include/usb_mass_storage.h
> index 9df3adc..058dcf1 100644
> --- a/include/usb_mass_storage.h
> +++ b/include/usb_mass_storage.h
> @@ -20,6 +20,9 @@
>   #define UMS_NUM_SECTORS		0
>   #endif
>
> +/* Wait at maximum 60 seconds for cable connection */
> +#define UMS_CABLE_READY_TIMEOUT	60
> +
>   struct ums {
>   	int (*read_sector)(struct ums *ums_dev,
>   			   ulong start, lbaint_t blkcnt, void *buf);
>

I was send some very useful fix to the ums. It is required for users who 
are using the same usb port for USB and UART purposes. Without this fix 
such users just can't use ums because it will always exit to prompt when 
user change the cable.

So I have few questions...
Marek, could you review this patch?
And what about the release, are you going to send pull request before 
the release?
If not, then is it possible to apply this patch directly to 
u-boot/master by Tom Rini?

Thank you,

-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com