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

[Przemyslaw Marczak <p.marczak@samsung.com>]

Hello,

On 01/13/2014 12:14 PM, Marek Vasut wrote:
> On Monday, January 13, 2014 at 10:18:51 AM, Przemyslaw Marczak wrote:
>> 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@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.
>
> Can you please share the schematic of such a cable in public?

Unfortunately I am not allowed to share such information.

> How does this
> "sharing" of USB and UART work? I am very curious here :-)

Regarding the USB sharing explanation - please refer to FSA9480 data 
sheet. It is available on the Internet.

I can also recommend looking into newest kernel code support for Trats2 
device.

>> So I have few questions...
>> Marek, could you review this patch?
>
> On it!
>
>> 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?
>
> PR will happen once I am through the load of patches in my mailbox.
>

Thank you for patch apply.

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