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Posts: 61 | Thanked: 60 times | Joined on Jul 2007 @ Erlangen
#18
i tested the speed for mine right now with the n900 being in mass storage mode with some quick check:

With delayed sync (the should actualy test the bus itself):

laptop ~> dd if=/dev/zero of=/media/Nokia\ N900/test bs=1024k count=100
100+0 records in
100+0 records out
104857600 bytes (105 MB) copied, 6.1257 s, 17.1 MB/s


Being mounted with sync option (should test the speed of the storage itself):

laptop ~> mount /media/Nokia\ N900/ -o remount,sync
~> dd if=/dev/zero of=/media/Nokia\ N900/test2 bs=1024k count=100

100+0 records in
100+0 records out
104857600 bytes (105 MB) copied, 41.3259 s, 2.5 MB/s





kernel output from command on the computer connected to N900:
laptop~> dmesg
[62971.967061] usb 1-4: new high speed USB device using ehci_hcd and address 6
[62972.082802] usb 1-4: New USB device found, idVendor=0421, idProduct=01c7
[62972.082827] usb 1-4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[62972.082846] usb 1-4: Product: N900 (Storage Mode)
[62972.082861] usb 1-4: Manufacturer: Nokia
[62972.082876] usb 1-4: SerialNumber: 372041756775
[62972.083114] usb 1-4: configuration #1 chosen from 2 choices
[62972.084205] scsi3 : SCSI emulation for USB Mass Storage devices
[62972.087127] usb-storage: device found at 6
[62972.087135] usb-storage: waiting for device to settle before scanning
[62973.087866] scsi 3:0:0:0: Direct-Access Nokia N900 031 PQ: 0 ANSI: 2
[62973.088334] sd 3:0:0:0: Attached scsi generic sg1 type 0
[62973.109172] scsi 3:0:0:1: Direct-Access Nokia N900 031 PQ: 0 ANSI: 2
[62973.109506] sd 3:0:0:1: Attached scsi generic sg2 type 0
[62973.115205] usb-storage: device scan complete
[62973.116413] sd 3:0:0:1: [sdc] Attached SCSI removable disk
[62973.123085] sd 3:0:0:0: [sdb] Attached SCSI removable disk
[62979.551831] sd 3:0:0:0: [sdb] 56631296 512-byte logical blocks: (28.9 GB/27.0 GiB)
[62979.552321] sd 3:0:0:0: [sdb] Assuming drive cache: write through
[62979.553561] sd 3:0:0:0: [sdb] Assuming drive cache: write through



The messages I get on the N900 when being connected are:

N900~> cat /proc/driver/musb_hdrc
Status: MHDRC, Mode=Peripheral (Power=f1, DevCtl=99)
OTG state: b_peripheral; active
Options: musb-dma, otg (peripheral+host), debug=0 [eps=12]
Peripheral address: 06
Root port status: 00000100
Gadget driver: g_file_storage

ep0 (hw0): 1buf, csr 0000 maxp 0000
(queue empty)

ep1in (hw1): 1buf, csr 2000 maxp 0200
(queue empty)

ep1out (hw1): 1buf, csr 0000 maxp 0200
req ce3e4f40, !short, 0/51




N900~> dmesg

[41951.144866] musb_hdrc periph: enabled ep1in for bulk IN, maxpacket 512
[41951.144897] musb_hdrc periph: enabled ep1out for bulk OUT, maxpacket 512
[41951.144958] g_file_storage gadget: high speed config #1




The N900 has the PR1.1 firmware update installed and i connect it directly to a USB port of my laptop (tried all ports, no difference) using the original Nokia USB cable.

If you experience problems maybe try the commands above and see if their output is any different for you (even with a windows machine you should be able to run 'dmesg' and 'cat /proc/driver/musb_hdrc' in the X Terminal). If yes, (i would expect it says not " g_file_storage gadget: high speed config #1" in the dmesg output but something else) maybe try these suggestions and see if things improve:

- try with the original Nokia USB cable as well as a non Nokia micro USB cable (if you have one - theoretically there could be some defect in the cable shipped)
- connect the device directly to the computers USB port and don't use a switch in between
- try all available USB ports on your computer (many older machines have only a few USB2.0 and several USB1.1 ports)
- try with a different computer if possible

Additionally it would be possible to load the musb_hdrc module on the N900 with debugging enabled so more info could be obtained, That however would require root access, so I would not recommend that to anyone who does not know what he is doing. If I encounter a speed drop I'll doo that myself and post the output here.



Two things I noticed while doing the checks:
- While being mounted on a compter, the MyDocs directory is empty as it got unmounted in the device itself. I assume this is to keep data intact, but wouldn't it make more sense to have MyDocs just mounted readonly, so no files can be copied there by accident that would later disappear under the remounted MyDocs partition (they would still use space though). Just a thought.

- the laptop dmesg output suggests that there are two mass storage devices exported from the N900, sdb (Scsi Disk b) and sdc. I can mount sdc1 (first partition on the 'disk') which turns out to be the MyDocs folder, but sdc, the second detected 'disc' does not even seem to contain a partition. Has anyone an idea what it is about?
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Last edited by greygoo; 2010-01-19 at 21:53.