should i expect my SD card slot to be supported by a USB driver?

[Robert P. J. Day]

On Tue, 24 May 2011, J wrote:

> On Tue, May 24, 2011 at 14:36, Robert P. J. Day <rpjday at crashcourse.ca> wrote:
> >
> >  in order to goof around and experiment with MMC/SD drivers on my
> > laptop running an updated 10.10, i popped in an SD card, then just did
> > a "diff" between the output of lsmod both before and after.  i was
> > expecting to see the load of some module with a name containing maybe
> > "sd" or "mmc".  instead, here's the output of diff:
> >
> > 2c2,6
> > < usb_storage            49778  0
> > ---
> >> nls_iso8859_1           4665  1
> >> nls_cp437               6383  1
> >> vfat                   10835  1
> >> fat                    55328  1 vfat
> >> usb_storage            49778  1
> >
> >
> > so this means my SD card slot is being supported by the usb_storage
> > driver?  i wasn't expecting that.  or am i just confused about
> > something?
> >
> > rday
>
> Depends on the reader. Ive seen some card readers (the Richoh ones
> come to mind, IIRC) that actually present their individual FUNCTIONS
> as block devices, regardless of whether you have a card plugged in
> or not.
>
> For example, if it supports SD, SDHC, and MMC, the kernel will
> actually show in sysfs three block devices sdb, sdc, and sdd, for
> each of those functions and that screws up some automated things
> that are looking at sysfs for block devices.
>
> Other readers function as USB devices and do not appear to the
> system until a card is inserted.
>
> So no,  you're not seeing anything terribly unusual.

  dang, this is disappointing.  i wanted to play with the MMC/SD
driver on my system so i was expecting that, when i inserted an SD
card, that would require the loading of the appropriate MMC drivers.

  instead, when i pop in the card, i see this in /var/log/messages:

May 25 07:02:02 lynx kernel: [31025.585661] usb 1-1.1: new high speed
USB device number 7 using ehci_hcd
May 25 07:02:02 lynx kernel: [31025.712208] scsi8 : usb-storage
1-1.1:1.0
May 25 07:02:03 lynx kernel: [31026.707562] scsi 8:0:0:0:
Direct-Access     Generic- Multi-Card       1.00 PQ: 0 ANSI: 0 CCS
May 25 07:02:03 lynx kernel: [31026.708755] sd 8:0:0:0: Attached scsi
generic sg2 type 0
May 25 07:02:04 lynx kernel: [31027.866315] sd 8:0:0:0: [sdb] 7729152
512-byte logical blocks: (3.95 GB/3.68 GiB)
May 25 07:02:04 lynx kernel: [31027.867146] sd 8:0:0:0: [sdb] Write
Protect is off
May 25 07:02:04 lynx kernel: [31027.872618]  sdb: sdb1 sdb2 sdb3
May 25 07:02:04 lynx kernel: [31027.874814] sd 8:0:0:0: [sdb] Attached
SCSI removable disk
May 25 07:02:04 lynx kernel: [31028.107379] EXT3-fs: barriers not
enabled
May 25 07:02:04 lynx kernel: [31028.108789] kjournald starting.
Commit interval 5 seconds
May 25 07:02:04 lynx kernel: [31028.126891] EXT3-fs (sdb2): using
internal journal
May 25 07:02:04 lynx kernel: [31028.126898] EXT3-fs (sdb2): recovery
complete
May 25 07:02:04 lynx kernel: [31028.126903] EXT3-fs (sdb2): mounted
filesystem with ordered data mode

  which doesn't do me a great deal of good if the device looks like a
SCSI USB storage device.  or am i misunderstanding something?  i was
anticipating running some of the MMC test routines on a blank card
but, under the circumstances, i'm not sure how i would do that.
thoughts?

rday

-- 

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Robert P. J. Day                                 Ottawa, Ontario, CANADA
                        http://crashcourse.ca

Twitter:                                       http://twitter.com/rpjday
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