readme.epca

powerpc内核mpc8241linux系统下char驱动程序

                            it's base address does not have to be (And cannot
                            be configured directly).

                        7.  Modified digiConfig to prompt for EISA/XEM cards.
                             
Files affected        : epca.c, epca.h, digi1.h, digiConfig
Release version       : 1.0.0g  (BETA)
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Programmer            : Ronnie Sanford
Date                  : August 21, 1996
Description (Verbose) : Made the following modifications:

                        1.  A problem affecting hard flow control was found 
                            in the termios2digi_h routine.  Specifically,
                            when the user activated hard flow control using
                            the CRTSCTS specification, the values used to 
                            program hard flow control on the board were 
                            incorrect.  The solution was to change a line
                            that read "res |= ((ch->m_dtr) | (ch->m_rts));"
                            to "res |= ((ch->m_cts) | (ch->m_rts));"  This 
                            line only applies if cflag & CRTSCTS.  Special
                            thanks to Matt Robinson ([e-mail]) who
                            found and fixed this problem.

                        2.  In previous betas the cud device was set to  CLOCAL
                            on driver boot up.  Likewise the ttyD device was
                            set to ~CLOCAL.  This has been fixed in this driver.
                            Now ttyD is CLOCAL and cud is ~CLOCAL.  The fix
                            for this can be found in pc_init.

                        3.  In ditty.c many changes were made to eliminate bugs
                            and warning messages.  Two ioctl calls were eliminated
                            as well a problem involving using the returned baud
                            index to determine the drivers baud rate.  Newer 
                            Linux kernels support higher baud rates by using
                            0x1000 bit.  When the returned value (ored with
                            0x1000) was used to reference our fbaud table a 
                            serious memory problem occurred.  This has been fixed.

                        4.  Added a request_region call to post_fep_init.  This
                            should cause the i/o ports being used to be 
                            registered with proc.
 
                        5.  Modified digiConfig to set all cud and ttyD devices
                            to read/write all permission.

                        6.  Developed a new apps called buildPCI that provides 
                            an easy way to build device nodes for PCI cards.
         
                        7.  Modified user.doc and technotes.doc document the
                            use of buildPCI.

Files affected        : epca.c, ditty.c, digiConfig, user.doc, technotes.doc 
Release version       : 1.0.0 (Official release)
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Programmer            : Ronnie Sanford
Date                  : August 21, 1996
Description (Verbose) : Made the following modifications:

                        1.  Removed code from pc_close which closes the 
                            drivers line discipline and restores its original
                            line discipline.  This is currently unecessary,
                            though future fast cook enhancements may require
                            this.

                        2.  Removed code in block_til_ready that set the 
                            asyncflags to either ASYNC_CALLOUT_ACTIVE, or
                            ASYNC_NORMAL_ACTIVE.  This code was redundant
                            as it already existed in block_til_ready.

                        3.  Added code in block_til_ready to cause a return
                            prior to schedule being called if the device 
                            was a CALLOUT device.  CALLOUT devices never
                            block on CD. (This was a serious bug that 
                            prevented the CALLOUT devices (ttyD) from 
                            functioning properly in some instances.

                            Make a change in the MODEMCHG_IND case of doevent
                            such that it does not require ASYNC_CALLOUT_ACTIVE
                            or ASYNC_NORMAL_ACTIVE to be set in order to 
                            unblock an open (Using wait_interruptible).

                            Thanks to Mike McLagan ([e-mail])
                            for diagnosing and fixing this problem. 

                        4.  Made changes to the disposition of CLOCAL on 
                            both SERIAL NORMAL and CALLOUT devices.  Both
                            device types now have CLOCAL active at default.
                            This may be changed with a stty command.

                        5.  Made changes to digiConfig such that it checks
                            major.h (If valid) for the correct major
                            numbers to use.

Files affected        : epca.c, digiConfig 
Release version       : 1.0.1a 


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Programmer            : Ronnie Sanford
Date                  : September 17, 1996
Description (Verbose) : Made the following modifications:
	
                        1. Modified pc_open such that it no longer checks 
                           the cflag value returned by termios2digi_c for
                           CLOCAL.  Digi hardware does not use this value
                           and thus termios2digi_c rightly screens this 
                           value out.  This driver checks for CLOCAL using
                           the drivers cflag value as known by the Linux OS.
                           (The value passed into termios2digi_c)

                        2. Modified termios2digi_c to screen out the 
                           CBAUDEX in CBAUD.  This error caused parity to
                           automaticaly be enabled on at higher baud rates.
		

                        3. Added the "disable_bh()" call to the shutdown
                           subroutine.  Hopefully this will allow the driver
                           to correctly clean up after itself when used as a
                           module. 

                        4. Added support for the PC/XI and 64K PC/XE cards.
                           This involved primarily modifying digiDload to
                           initialize and boot the new cards; however 
                           driver modifications were also required to 
                           provide the proper windowing for the newly 
                           supported cards. (Code was also added to 
                           determine the memory segment of the XI card as
                           that card may have more than 64K.  Currently
                           digiDload assumes a 64K XI card.)

                        5. Added subroutine called epca_setup that can be 
                           called during LILO boot up.  This provides the 
                           user an easy way to change cards; without 
                           running digiConfig and without recompiling the
                           kernel.  Added code in pc_init and pc_open to
                           support the epca_setup routine.  pc_init checks
                           the liloconfig flag (Which is set by epca_setup)
                           to determine if the driver is using the LILO 
                           arguments.  If not pc_init loads the board data 
                           found in epcaconfig.h; if so it DOESN'T load
                           epcaconfig data depending on epca_setup to handle 
                           board configuration.  pc_open has been modified 
                           such that it checks to ensure that no errors
                           occurred during the LILO boot process.  If a 
                           user attempts to boot the driver (via. LILO)
                           with incorrect data, the open will fail. 

                        6. Modified the windowing routines pcxe_rxwinon
                           and pcxe_txwinon routines.  A bug existed such
                           that those routines checked to see if the rxwin 
                           and txwin flags were reset.  If so they assumed 
                           the board was an XI or 64K XE.  Furthermore since
                           these flags were never initialized in our driver
                           sometimes they were 0 and therefore caused a 
                           memory fault (Or at least a window overrun).  This
                           code has been removed since the pcxe shares 
                           nothing in common with the 64K XI and XE. 

                        7. Added code in pc_init to set the memory_seg for
                           the various boards.  This code was necessary to
                           correct a bug in the PCXE, PCXEVE code where 
                           receive and transmit pointers were being calculated
                           from an uninitialized variable (memory_seg). 

                        8. Modified digiConfig to allow 64K PC/XI and 64K
                           PC/XE cards to be configured.
                           
                        9. Made changes to support the new 2.1.x development 
                           kernel.  In particular this required changing all
                           references to vremap to ioremap. 

                       10. Modified digiConfig such that it now generates 
                           node names corresponding to their internal 
                           as opposed to the label on the port itself.  Nodes
                           (ttyD?? and cud??) now start at 0.  Example:
                           ttyD0 and cud0 represent port 1 on any supported
                           Digi product.  A similar change has been made
                           in buildPCI.c. 

                       12. At the early portion of post_fep_init if a PCI
                           card is detected a warning message could be given
                           incorrectly if 64 ports were attached to a PCI 
                           card.  The below line :

                           epcaassert(bd->numports > 64,"PCI returned a invalid number of ports"); 
    
                           was changed to :

                           epcaassert(bd->numports <= 64,"PCI returned a invalid number of ports"); 

                           Remember that epcaassert checks for NOT true.
                           Special thanks to Daniel Taylor for fixing this.

                       13. Modified the epcaparam routine.  In version 100
                           and 101a there was a line that looked like the 
                           below:

                             if (ch->omodem != mval)
                           
                           The problem with this line was that the first time
                           through omodem was not initialized.  Secondly, since
                           many TIOC commands did not alter mval (They use
                           a different variable) changes made by these commands
                           could be lost.  This line was changed to:

                             mval ^= ch->modemfake & (mval ^ ch->modem);

                             if (ch->omodem ^ mval)

                       14. Modified digiConfig in such a way that it checks 
                           the version number of the kernel and if it finds
                           a 2.x.x kernel or higher it reads the necessary 
                           major numbers for cud and ttyD devices from major.h.
                           This was also done in prior versions but these
                           versions required a #define which identified the 
                           kernel as a version which did not have major numbers
                           assigned to Digi systems.  This #define is no 
                           longer required allowing the same source tree for
                           multiple kernel releases.

                       15. Used macros to replace kernel specific calls such
                           as put_fs_long, get_fs_long, put_user, and get_user
                           the kernel version is now detected and the macro
                           is defined as to correspond with the kernel it
                           is being compiled into.  Again this was done to
                           allow one source tree for multiple kernel releases. 

                       16. Added support for the new 2.1.x development kernels
                           to digiInstall.

Files affected        : epca.c, digiConfig 
Release version       : 1.1.0
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Programmer            : Daniel Taylor
Date                  : April 25, 1997
Description (Verbose) : Updated driver:
                        1.  Fixed DCD bug. (&tq_scheduler)
                        2.  Removed BH handler code, as it was only handling
                            hangups, and not being called for that.
                        3.  Namespace cleanup (DIGI_TIMER2 => DIGI_TIMER)
                        4.  Updated to 2.1.36, removed #ifdefs for earlier
                            kernel revisions.
Files affected        : epca.c
Release version       : 1.1.1  (BETA)
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Programmer            : Daniel Taylor
Date                  : March 11, 1999
Description (Verbose) : Updated driver:
                        1.  Simultaneous data and modem change events were
			    resulting in the modem change events not being
			    recognized. Fixed.
                        2.  Modified pc_info device name to work better
			    with devfs.
Files affected        : epca.c
Release version       : 1.3.0-K 
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