1. 14 May, 2013 1 commit
  2. 25 Jul, 2012 1 commit
    • Axel Lin's avatar
      ata: use module_pci_driver · 2fc75da0
      Axel Lin authored
      This patch converts the drivers in drivers/ata/* to use module_pci_driver()
      macro which makes the code smaller and a bit simpler.
      Signed-off-by: 's avatarAxel Lin <axel.lin@gmail.com>
      Cc: Alan Cox <alan@linux.intel.com>
      Cc: Jeff Garzik <jgarzik@pobox.com>
      Cc: Mikael Pettersson <mikpe@it.uu.se>
      Cc: Mark Lord <kernel@teksavvy.com>
      Cc: Jeremy Higdon <jeremy@sgi.com>
      Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@redhat.com>
      2fc75da0
  3. 23 Jul, 2011 4 commits
    • Joe Perches's avatar
      ata: sata_via: Use dev_dbg · 5b933e63
      Joe Perches authored
      Use normal debugging path for dynamic debug capability.
      
      Convert dev_printk(KERN_DEBUG to dev_dbg(
      Signed-off-by: 's avatarJoe Perches <joe@perches.com>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@pobox.com>
      5b933e63
    • Joe Perches's avatar
      ata: Add and use ata_print_version_once · 06296a1e
      Joe Perches authored
      Use a single mechanism to show driver version.
      Reduces text a tiny bit too.
      
      Remove uses of static int printed_version
      Add and use ata_print_version(const struct device *, const char *ver)
      and ata_print_version_once.
      
      $ size drivers/ata/built-in.*
         text	   data	    bss	    dec	    hex	filename
       544969	  73893	 116584	 735446	  b38d6	drivers/ata/built-in.allyesconfig.ata.o
       543870	  73893	 116592	 734355	  b34ad	drivers/ata/built-in.allyesconfig.print_once.o
       141328	  14689	   4220	 160237	  271ed	drivers/ata/built-in.defconfig.ata.o
       141212	  14689	   4220	 160121	  27179	drivers/ata/built-in.defconfig.print_once.o
      Signed-off-by: 's avatarJoe Perches <joe@perches.com>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@pobox.com>
      06296a1e
    • Joe Perches's avatar
      ata: Convert ata_<foo>_printk(KERN_<LEVEL> to ata_<foo>_<level> · a9a79dfe
      Joe Perches authored
      Saves text by removing nearly duplicated text format strings by
      creating ata_<foo>_printk functions and printf extension %pV.
      
      ata defconfig size shrinks ~5% (~8KB), allyesconfig ~2.5% (~13KB)
      
      Format string duplication comes from:
      
       #define ata_link_printk(link, lv, fmt, args...) do { \
             if (sata_pmp_attached((link)->ap) || (link)->ap->slave_link)    \
                     printk("%sata%u.%02u: "fmt, lv, (link)->ap->print_id,   \
                            (link)->pmp , ##args); \
             else \
                     printk("%sata%u: "fmt, lv, (link)->ap->print_id , ##args); \
             } while(0)
      
      Coalesce long formats.
      
      $ size drivers/ata/built-in.*
         text	   data	    bss	    dec	    hex	filename
       544969	  73893	 116584	 735446	  b38d6	drivers/ata/built-in.allyesconfig.ata.o
       558429	  73893	 117864	 750186	  b726a	drivers/ata/built-in.allyesconfig.dev_level.o
       141328	  14689	   4220	 160237	  271ed	drivers/ata/built-in.defconfig.ata.o
       149567	  14689	   4220	 168476	  2921c	drivers/ata/built-in.defconfig.dev_level.o
      Signed-off-by: 's avatarJoe Perches <joe@perches.com>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@pobox.com>
      a9a79dfe
    • Joe Perches's avatar
      ata: Convert dev_printk(KERN_<LEVEL> to dev_<level>( · a44fec1f
      Joe Perches authored
      Saves a bit of text as the call takes fewer args.
      
      Coalesce a few formats.
      Convert a few bare printks to pr_cont.
      
      $ size drivers/ata/built-in.o*
         text	   data	    bss	    dec	    hex	filename
       558429	  73893	 117864	 750186	  b726a	drivers/ata/built-in.o.allyesconfig.new
       559574	  73893	 117888	 751355	  b76fb	drivers/ata/built-in.o.allyesconfig.old
       149567	  14689	   4220	 168476	  2921c	drivers/ata/built-in.o.defconfig.new
       149851	  14689	   4220	 168760	  29338	drivers/ata/built-in.o.defconfig.old
      Signed-off-by: 's avatarJoe Perches <joe@perches.com>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@pobox.com>
      a44fec1f
  4. 31 Mar, 2011 1 commit
  5. 02 Mar, 2011 1 commit
  6. 19 Nov, 2010 1 commit
  7. 22 Oct, 2010 1 commit
  8. 07 Jun, 2010 1 commit
  9. 02 Jun, 2010 1 commit
  10. 25 May, 2010 3 commits
    • Tejun Heo's avatar
      libata-sff: separate out BMDMA init · 1c5afdf7
      Tejun Heo authored
      Separate out ata_pci_bmdma_prepare_host() and ata_pci_bmdma_init_one()
      from their SFF counterparts.  SFF ones no longer try to initialize
      BMDMA or set PCI master.
      Signed-off-by: 's avatarTejun Heo <tj@kernel.org>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@redhat.com>
      1c5afdf7
    • Tejun Heo's avatar
      libata-sff: separate out BMDMA irq handler · c3b28894
      Tejun Heo authored
      Separate out BMDMA irq handler from SFF irq handler.  The misnamed
      host_intr() functions are renamed to ata_sff_port_intr() and
      ata_bmdma_port_intr().  Common parts are factored into
      __ata_sff_port_intr() and __ata_sff_interrupt() and used by sff and
      bmdma interrupt routines.
      
      All BMDMA drivers now use ata_bmdma_interrupt() or
      ata_bmdma_port_intr() while all non-BMDMA SFF ones use
      ata_sff_interrupt() or ata_sff_port_intr().
      
      For now, ata_pci_sff_init_one() uses ata_bmdma_interrupt() as it's
      used by both SFF and BMDMA drivers.
      Signed-off-by: 's avatarTejun Heo <tj@kernel.org>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@redhat.com>
      c3b28894
    • Tejun Heo's avatar
      libata-sff: ata_sff_irq_clear() is BMDMA specific · 37f65b8b
      Tejun Heo authored
      ata_sff_irq_clear() is BMDMA specific.  Rename it to
      ata_bmdma_irq_clear(), move it to ata_bmdma_port_ops and make
      ->sff_irq_clear() optional.
      
      Note: ata_bmdma_irq_clear() is actually only needed by ata_piix and
            possibly by sata_sil.  This should be moved to respective low
            level drivers later.
      Signed-off-by: 's avatarTejun Heo <tj@kernel.org>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@redhat.com>
      37f65b8b
  11. 01 Mar, 2010 2 commits
  12. 03 Nov, 2009 1 commit
  13. 13 Apr, 2009 1 commit
  14. 25 Mar, 2009 1 commit
  15. 16 Jan, 2009 1 commit
  16. 04 Nov, 2008 1 commit
  17. 31 Oct, 2008 1 commit
    • Tejun Heo's avatar
      sata_via: fix support for 5287 · b9d5b89b
      Tejun Heo authored
      5287 used to be treated as vt6420 but it didn't work.  It's new family
      of controllers called vt8251 which hosts four SATA ports as M/S of the
      two ATA ports.  This configuration is rather peculiar in that although
      the M/S devices are on the same port, each have its own SCR (or
      equivalent link status/control) registers which screws up the
      port-link-device hierarchy assumed by libata.  Another controller
      which falls into this category is ata_piix w/ SIDPR access.
      
      libata now has facility to deal with this class of controllers named
      slave_link.  A low level driver for such controllers can just call
      ata_slave_link_init() on the respective ports and libata will handle
      all the difficult parts like following up with single SRST after
      hardresetting both ports.
      
      This patch creates new controller class vt8251, implements slave_link
      aware init sequence and config space based SCR access for it and moves
      5287 to the new class.
      
      This patch is based on Joseph Chan's larger patch which was created
      before slave_link was implemented in libata.
      
        http://thread.gmane.org/gmane.linux.kernel.commits.mm/40640Signed-off-by: 's avatarTejun Heo <tj@kernel.org>
      Cc: Joseph Chan <JosephChan@via.com.tw>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@redhat.com>
      b9d5b89b
  18. 23 Oct, 2008 1 commit
  19. 29 Sep, 2008 1 commit
    • Tejun Heo's avatar
      libata: make SCR access ops per-link · 82ef04fb
      Tejun Heo authored
      Logically, SCR access ops should take @link; however, there was no
      compelling reason to convert all SCR access ops when adding @link
      abstraction as there's one-to-one mapping between a port and a non-PMP
      link.  However, that assumption won't hold anymore with the scheduled
      addition of slave link.
      
      Make SCR access ops per-link.
      Signed-off-by: 's avatarTejun Heo <tj@kernel.org>
      Signed-off-by: 's avatarJeff Garzik <jgarzik@redhat.com>
      82ef04fb
  20. 17 Apr, 2008 9 commits
    • Tejun Heo's avatar
      libata: restructure SFF post-reset readiness waits · 705e76be
      Tejun Heo authored
      Previously, post-softreset readiness is waited as follows.
      
      1. ata_sff_wait_after_reset() waits for 150ms and then for
         ATA_TMOUT_FF_WAIT if status is 0xff and other conditions meet.
      
      2. ata_bus_softreset() finishes with -ENODEV if status is still 0xff.
         If not, continue to #3.
      
      3. ata_bus_post_reset() waits readiness of dev0 and/or dev1 depending
         on devmask using ata_sff_wait_ready().
      
      And for post-hardreset readiness,
      
      1. ata_sff_wait_after_reset() waits for 150ms and then for
         ATA_TMOUT_FF_WAIT if status is 0xff and other conditions meet.
      
      2. sata_sff_hardreset waits for device readiness using
         ata_sff_wait_ready().
      
      This patch merges and unifies post-reset readiness waits into
      ata_sff_wait_ready() and ata_sff_wait_after_reset().
      
      ATA_TMOUT_FF_WAIT handling is merged into ata_sff_wait_ready().  If TF
      status is 0xff, link status is unknown and the port is SATA, it will
      continue polling till ATA_TMOUT_FF_WAIT.
      
      ata_sff_wait_after_reset() is updated to perform the following steps.
      
      1. waits for 150ms.
      
      2. waits for dev0 readiness using ata_sff_wait_ready().  Note that
         this is done regardless of devmask, as ata_sff_wait_ready() handles
         0xff status correctly, this preserves the original behavior except
         that it may wait longer after softreset if link is online but
         status is 0xff.  This behavior change is very unlikely to cause any
         actual difference and is intended.  It brings softreset behavior to
         that of hardreset.
      
      3. waits for dev1 readiness just the same way ata_bus_post_reset() did.
      
      Now both soft and hard resets call ata_sff_wait_after_reset() after
      reset to wait for readiness after resets.  As
      ata_sff_wait_after_reset() contains calls to ->sff_dev_select(),
      explicit call near the end of sata_sff_hardreset() is removed.
      
      This change makes reset implementation simpler and more consistent.
      
      While at it, make the magical 150ms wait post-reset wait duration a
      constant and ata_sff_wait_ready() and ata_sff_wait_after_reset() take
      @link instead of @AP.  This is to make them consistent with other
      reset helpers and ease core changes.
      
      pata_scc is updated accordingly.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      705e76be
    • Tejun Heo's avatar
      libata: rename SFF port ops · 5682ed33
      Tejun Heo authored
      Add sff_ prefix to SFF specific port ops.
      
      This rename is in preparation of separating SFF support out of libata
      core layer.  This patch strictly renames ops and doesn't introduce any
      behavior difference.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      5682ed33
    • Tejun Heo's avatar
      libata: rename SFF functions · 9363c382
      Tejun Heo authored
      SFF functions have confusing names.  Some have sff prefix, some have
      bmdma, some std, some pci and some none.  Unify the naming by...
      
      * SFF functions which are common to both BMDMA and non-BMDMA are
        prefixed with ata_sff_.
      
      * SFF functions which are specific to BMDMA are prefixed with
        ata_bmdma_.
      
      * SFF functions which are specific to PCI but apply to both BMDMA and
        non-BMDMA are prefixed with ata_pci_sff_.
      
      * SFF functions which are specific to PCI and BMDMA are prefixed with
        ata_pci_bmdma_.
      
      * Drop generic prefixes from LLD specific routines.  For example,
        bfin_std_dev_select -> bfin_dev_select.
      
      The following renames are noteworthy.
      
        ata_qc_issue_prot() -> ata_sff_qc_issue()
        ata_pci_default_filter() -> ata_bmdma_mode_filter()
        ata_dev_try_classify() -> ata_sff_dev_classify()
      
      This rename is in preparation of separating SFF support out of libata
      core layer.  This patch strictly renames functions and doesn't
      introduce any behavior difference.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      9363c382
    • Tejun Heo's avatar
      libata: kill ata_chk_status() · 6fd36390
      Tejun Heo authored
      ata_chk_status() just calls ops->check_status and it only adds
      confusion with other status functions.  Kill it.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      Signed-off-by: 's avatarJeff Garzik <jeff@garzik.org>
      6fd36390
    • Tejun Heo's avatar
      libata: make reset related methods proper port operations · a1efdaba
      Tejun Heo authored
      Currently reset methods are not specified directly in the
      ata_port_operations table.  If a LLD wants to use custom reset
      methods, it should construct and use a error_handler which uses those
      reset methods.  It's done this way for two reasons.
      
      First, the ops table already contained too many methods and adding
      four more of them would noticeably increase the amount of necessary
      boilerplate code all over low level drivers.
      
      Second, as ->error_handler uses those reset methods, it can get
      confusing.  ie. By overriding ->error_handler, those reset ops can be
      made useless making layering a bit hazy.
      
      Now that ops table uses inheritance, the first problem doesn't exist
      anymore.  The second isn't completely solved but is relieved by
      providing default values - most drivers can just override what it has
      implemented and don't have to concern itself about higher level
      callbacks.  In fact, there currently is no driver which actually
      modifies error handling behavior.  Drivers which override
      ->error_handler just wraps the standard error handler only to prepare
      the controller for EH.  I don't think making ops layering strict has
      any noticeable benefit.
      
      This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and
      their PMP counterparts propoer ops.  Default ops are provided in the
      base ops tables and drivers are converted to override individual reset
      methods instead of creating custom error_handler.
      
      * ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs
        aren't accessible.  sata_promise doesn't need to use separate
        error_handlers for PATA and SATA anymore.
      
      * softreset is broken for sata_inic162x and sata_sx4.  As libata now
        always prefers hardreset, this doesn't really matter but the ops are
        forced to NULL using ATA_OP_NULL for documentation purpose.
      
      * pata_hpt374 needs to use different prereset for the first and second
        PCI functions.  This used to be done by branching from
        hpt374_error_handler().  The proper way to do this is to use
        separate ops and port_info tables for each function.  Converted.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      a1efdaba
    • Tejun Heo's avatar
      libata: implement and use ops inheritance · 029cfd6b
      Tejun Heo authored
      libata lets low level drivers build ata_port_operations table and
      register it with libata core layer.  This allows low level drivers
      high level of flexibility but also burdens them with lots of
      boilerplate entries.
      
      This becomes worse for drivers which support related similar
      controllers which differ slightly.  They share most of the operations
      except for a few.  However, the driver still needs to list all
      operations for each variant.  This results in large number of
      duplicate entries, which is not only inefficient but also error-prone
      as it becomes very difficult to tell what the actual differences are.
      
      This duplicate boilerplates all over the low level drivers also make
      updating the core layer exteremely difficult and error-prone.  When
      compounded with multi-branched development model, it ends up
      accumulating inconsistencies over time.  Some of those inconsistencies
      cause immediate problems and fixed.  Others just remain there dormant
      making maintenance increasingly difficult.
      
      To rectify the problem, this patch implements ata_port_operations
      inheritance.  To allow LLDs to easily re-use their own ops tables
      overriding only specific methods, this patch implements poor man's
      class inheritance.  An ops table has ->inherits field which can be set
      to any ops table as long as it doesn't create a loop.  When the host
      is started, the inheritance chain is followed and any operation which
      isn't specified is taken from the nearest ancestor which has it
      specified.  This operation is called finalization and done only once
      per an ops table and the LLD doesn't have to do anything special about
      it other than making the ops table non-const such that libata can
      update it.
      
      libata provides four base ops tables lower drivers can inherit from -
      base, sata, pmp, sff and bmdma.  To avoid overriding these ops
      accidentaly, these ops are declared const and LLDs should always
      inherit these instead of using them directly.
      
      After finalization, all the ops table are identical before and after
      the patch except for setting .irq_handler to ata_interrupt in drivers
      which didn't use to.  The .irq_handler doesn't have any actual effect
      and the field will soon be removed by later patch.
      
      * sata_sx4 is still using old style EH and currently doesn't take
        advantage of ops inheritance.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      029cfd6b
    • Tejun Heo's avatar
      libata: implement and use SHT initializers · 68d1d07b
      Tejun Heo authored
      libata lets low level drivers build scsi_host_template and register it
      to the SCSI layer.  This allows low level drivers high level of
      flexibility but also burdens them with lots of boilerplate entries.
      
      This patch implements SHT initializers which can be used to initialize
      all the boilerplate entries in a sht.  Three variants of them are
      implemented - BASE, BMDMA and NCQ - for different types of drivers.
      Note that entries can be overriden by putting individual initializers
      after the helper macro.
      
      All sht tables are identical before and after this patch.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      68d1d07b
    • Tejun Heo's avatar
      libata: normalize port_info, port_operations and sht tables · 6bd99b4e
      Tejun Heo authored
      Over the time, port info, ops and sht structures developed quite a bit
      of inconsistencies.  This patch updates drivers.
      
      * Enable/disable_pm callbacks added to all ahci ops tables.
      
      * Every driver for SFF controllers now uses ata_sff_port_start()
        instead of ata_port_start() unless the driver has custom
        implementation.
      
      * Every driver for SFF controllers now uses ata_pci_default_filter()
        unless the driver has custom implementation.
      
      * Removed an odd port_info->sht initialization from ata_piix.c.
        Likely a merge byproduct.
      
      * A port which has ATA_FLAG_SATA set doesn't need to set cable_detect
        to ata_cable_sata().  Remove it from via and mv port ops.
      
      * Some drivers had unnecessary .max_sectors initialization which is
        ignored and was missing .slave_destroy callback.  Fixed.
      
      * Removed unnecessary sht initializations port_info's.
      
      * Removed onsolete scsi device suspend/resume callbacks from
        pata_bf54x.
      
      * No reason to set ata_pci_default_filter() and bmdma functions for
        PIO-only drivers.  Remove those callbacks and replace
        ata_bmdma_irq_clear with ata_noop_irq_clear.
      
      * pata_platform sets port_start to ata_dummy_ret0.  port_start can
        just be set to NULL.
      
      * sata_fsl supports NCQ but was missing qc_defer.  Fixed.
      
      * pata_rb600_cf implements dummy port_start.  Removed.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      6bd99b4e
    • Tejun Heo's avatar
      libata: prefer hardreset · cf480626
      Tejun Heo authored
      When both soft and hard resets are available, libata preferred
      softreset till now.  The logic behind it was to be softer to devices;
      however, this doesn't really help much.  Rationales for the change:
      
      * BIOS may freeze lock certain things during boot and softreset can't
        unlock those.  This by itself is okay but during operation PHY event
        or other error conditions can trigger hardreset and the device may
        end up with different configuration.
      
        For example, after a hardreset, previously unlockable HPA can be
        unlocked resulting in different device size and thus revalidation
        failure.  Similar condition can occur during or after resume.
      
      * Certain ATAPI devices require hardreset to recover after certain
        error conditions.  On PATA, this is done by issuing the DEVICE RESET
        command.  On SATA, COMRESET has equivalent effect.  The problem is
        that DEVICE RESET needs its own execution protocol.
      
        For SFF controllers with bare TF access, it can be easily
        implemented but more advanced controllers (e.g. ahci and sata_sil24)
        require specialized implementations.  Simply using hardreset solves
        the problem nicely.
      
      * COMRESET initialization sequence is the norm in SATA land and many
        SATA devices don't work properly if only SRST is used.  For example,
        some PMPs behave this way and libata works around by always issuing
        hardreset if the host supports PMP.
      
        Like the above example, libata has developed a number of mechanisms
        aiming to promote softreset to hardreset if softreset is not going
        to work.  This approach is time consuming and error prone.
      
        Also, note that, dependingon how you read the specs, it could be
        argued that PMP fan-out ports require COMRESET to start operation.
        In fact, all the PMPs on the market except one don't work properly
        if COMRESET is not issued to fan-out ports after PMP reset.
      
      * COMRESET is an integral part of SATA connection and any working
        device should be able to handle COMRESET properly.  After all, it's
        the way to signal hardreset during reboot.  This is the most used
        and recommended (at least by the ahci spec) method of resetting
        devices.
      
      So, this patch makes libata prefer hardreset over softreset by making
      the following changes.
      
      * Rename ATA_EH_RESET_MASK to ATA_EH_RESET and use it whereever
        ATA_EH_{SOFT|HARD}RESET used to be used.  ATA_EH_{SOFT|HARD}RESET is
        now only used to tell prereset whether soft or hard reset will be
        issued.
      
      * Strip out now unneeded promote-to-hardreset logics from
        ata_eh_reset(), ata_std_prereset(), sata_pmp_std_prereset() and
        other places.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      cf480626
  21. 15 Feb, 2008 1 commit
  22. 06 Feb, 2008 1 commit
  23. 29 Oct, 2007 1 commit
  24. 14 Oct, 2007 1 commit
  25. 12 Oct, 2007 2 commits
    • Tejun Heo's avatar
      sata_via: kill SATA_PATA_SHARING register handling · b6d6c746
      Tejun Heo authored
      The SATA_PATA_SHARING register doesn't have anything to do with the
      SATA part of the controller.  It indicates whether an extern SATA PHY
      is attached to the PATA part of the controller and if so how it is
      wired.  As the PATA part is driven by pata_via, sata_via has no reason
      to care about that.  Also, pata_via should work fine under all
      configurations.
      
      This patch removes unnecessary attach failures.  It seems recent via
      chipsets are defaulting to different values or are actually connected
      to SATA PHY triggering this more often.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      Signed-off-by: 's avatarJeff Garzik <jeff@garzik.org>
      b6d6c746
    • Tejun Heo's avatar
      libata: implement and use ata_port_desc() to report port configuration · cbcdd875
      Tejun Heo authored
      Currently, port configuration reporting has the following problems.
      
      * iomapped address is reported instead of raw address
      * report contains irrelevant fields or lacks necessary fields for
        non-SFF controllers.
      * host->irq/irq2 are there just for reporting and hacky.
      
      This patch implements and uses ata_port_desc() and
      ata_port_pbar_desc().  ata_port_desc() is almost identical to
      ata_ehi_push_desc() except that it takes @AP instead of @ehi, has no
      locking requirement, can only be used during host initialization and "
      " is used as separator instead of ", ".  ata_port_pbar_desc() is a
      helper to ease reporting of a PCI BAR or an offsetted address into it.
      
      LLD pushes whatever description it wants using the above two
      functions.  The accumulated description is printed on host
      registration after "[S/P]ATA max MAX_XFERMODE ".
      
      SFF init helpers and ata_host_activate() automatically add
      descriptions for addresses and irq respectively, so only LLDs which
      isn't standard SFF need to add custom descriptions.  In many cases,
      such controllers need to report different things anyway.
      Signed-off-by: 's avatarTejun Heo <htejun@gmail.com>
      Signed-off-by: 's avatarJeff Garzik <jeff@garzik.org>
      cbcdd875