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* dz.c: Resource managementMaciej W. Rozycki2008-02-071-101/+188
| | | | | | | | | | | | | | | | | | | | | | | This is a set of changes to implement proper resource management in the driver, including iomem space reservation and operating on physical addresses ioremap()ped appropriately using accessory functions rather than unportable direct assignments. Some adjustments to code are made to reflect the architecture of the interface, which is a centrally controlled multiport (or, as referred to from DEC documentation, a serial line multiplexer, going up to 8 lines originally) rather than a bundle of separate ports. Types are changed, where applicable, to specify the width of hardware registers explicitly. The interrupt handler is now managed in the ->startup() and ->shutdown() calls for consistency with other drivers and also in preparation to handle the handover from the initial firmware-based console gracefully. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dz.c: Use a helper to cast from "struct uart_port *"Maciej W. Rozycki2008-02-071-11/+16
| | | | | | | | | | | | | | Replace all casts from "struct uart_port *" to "struct dz_port *" with a construct based on container_of(). This makes the conversion work irrespective of where the former struct is located within the latter. By popular request I have implemented it as an inline function rather than a macro this time. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dz: clean up and improve the setup of termios settingsMaciej W. Rozycki2008-02-071-49/+54
| | | | | | | | | | | | | | | | | A set of changes to the way termios settings are propagated to the serial port hardware. The DZ11 only supports a selection of fixed baud settings, so some requests may not be fulfilled. Keep the old setting in such a case and failing that resort to 9600bps. Also add a missing update of the transmit timeout. And remove the explicit encoding of the line selected from writes to the Line Parameters Register as it has been preencoded by the ->set_termios() call already. Finally, remove a duplicate macro for the Receiver Enable bit. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dz: handle special conditions on reception correctlyMaciej W. Rozycki2008-02-071-38/+44
| | | | | | | | | | | Handle the read and ignore status masks correctly. Handle the BREAK condition as expected: a framing error with a null character is a BREAK, any other framing error is a framing error indeed. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dz: fix locking issuesMaciej W. Rozycki2008-02-071-11/+12
| | | | | | | | | | | The ->start_tx(), ->stop_tx() and ->stop_rx() backends are called with the port's lock already taken. Remove locking from within them and wrap around calls as necessary. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dz: rename the serial console structureMaciej W. Rozycki2008-02-071-3/+3
| | | | | | | | | | Rename the serial console structure so that `modpost' does not complain about a reference to an "init" section -- "_console" is magic. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dz: add and reorder inclusions, remove unneeded onesMaciej W. Rozycki2008-02-071-10/+13
| | | | | | | | | | Sort the header inclusions, add a few that are needed but pulled indirectly only and remove ones that are not really used. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dz: don't panic() when request_irq() failsMaciej W. Rozycki2008-02-071-5/+15
| | | | | | | | | | | Well, panic() is a little bit undue if request_irq() fails; there is probably no need to justify it any further. Handle the case gracefully, by unregistering the driver. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dz: always check if it is safe to console_putchar()Maciej W. Rozycki2008-02-071-2/+2
| | | | | | | | | | | | | | | | | | Polled transmission is tricky enough with the DZ11 design. While "loop" is set to a high value, conceptually you are not allowed to transmit without checking whether the device offers the right transmission line (yes, it is the device that selects the line -- the driver has no control over it other than disabling the transmitter offered if it is the wrong one), so the loop has to be run at least once. Well, the '1977 or PDP11 view of how serial lines should be handled... Except that the serial interface used to be quite an impressive board back then rather than chip. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Cc: Jiri Slaby <jirislaby@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Remove pointless casts from void pointersJeff Garzik2008-02-061-1/+1
| | | | | | | | | | | | | | | | | | | | | | Mostly in and around irq handlers. Signed-off-by: Jeff Garzik <jgarzik@redhat.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: "Luck Tony" <tony.luck@intel.com> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: Dmitry Torokhov <dtor@mail.ru> Cc: Karsten Keil <kkeil@suse.de> Acked-by: "John W. Linville" <linville@tuxdriver.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: David Brownell <david-b@pacbell.net> Cc: "Antonino A. Daplas" <adaplas@pol.net> Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com> Acked-by: Holger Schurig <hs4233@mail.mn-solutions.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] dz: remove struct pt_regs referencesMaciej W. Rozycki2007-03-051-4/+3
| | | | | | | | | Remove remaining references to saved registers now that uart_handle_sysrq_char() does not want them. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] tty: switch to ktermiosAlan Cox2006-12-081-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is the grungy swap all the occurrences in the right places patch that goes with the updates. At this point we have the same functionality as before (except that sgttyb() returns speeds not zero) and are ready to begin turning new stuff on providing nobody reports lots of bugs If you are a tty driver author converting an out of tree driver the only impact should be termios->ktermios name changes for the speed/property setting functions from your upper layers. If you are implementing your own TCGETS function before then your driver was broken already and its about to get a whole lot more painful for you so please fix it 8) Also fill in c_ispeed/ospeed on init for most devices, although the current code will do this for you anyway but I'd like eventually to lose that extra paranoia [akpm@osdl.org: bluetooth fix] [mp3@de.ibm.com: sclp fix] [mp3@de.ibm.com: warning fix for tty3270] [hugh@veritas.com: fix tty_ioctl powerpc build] [jdike@addtoit.com: uml: fix ->set_termios declaration] Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Martin Peschke <mp3@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@de.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] dz: Fixes to make it workMaciej W. Rozycki2006-12-071-185/+186
| | | | | | | | | | | | | | | | | | | | | This a set of fixes mostly to make the driver actually work: 1. Actually select the line for setting parameters and receiver disable/enable. 2. Select the line for receive and transmit interrupt handling correctly. 3. Report the transmitter empty state correctly. 4. Set the I/O type of ports correctly. 5. Perform polled transmission correctly. 6. Don't fix the console line at ttyS3. 7. Magic SysRq support. 8. Various small bits here and there. Tested with a DECstation 2100 (thanks Flo for making this possible). [akpm@osdl.org: fix typo] Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* IRQ: Maintain regs pointer globally rather than passing to IRQ handlersDavid Howells2006-10-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
* [SERIAL] dz: Fix compilation errorMartin Michlmayr2006-07-091-1/+1
| | | | | | | | | | | | | | Fix the following compilation error in the dz serial driver that got introduced with the "kernel console should send CRLF not LFCR" change. CC drivers/serial/dz.o drivers/serial/dz.c: In function 'dz_console_putchar': drivers/serial/dz.c:679: error: 'uport' undeclared (first use in this function) drivers/serial/dz.c:679: error: (Each undeclared identifier is reported only once drivers/serial/dz.c:679: error: for each function it appears in.) Signed-off-by: Martin Michlmayr <tbm@cyrius.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] irq-flags: serial: Use the new IRQF_ constantsThomas Gleixner2006-07-021-1/+1
| | | | | | | | | | Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] devfs: Remove devfs support from the serial subsystemGreg Kroah-Hartman2006-06-261-4/+0
| | | | | | Also fixes all serial drivers. Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* [SERIAL] kernel console should send CRLF not LFCRRussell King2006-03-201-7/+5
| | | | | | | | | | | Glen Turner reported that writing LFCR rather than the more traditional CRLF causes issues with some terminals. Since this aflicts many serial drivers, extract the common code to a library function (uart_console_write) and arrange for each driver to supply a "putchar" function. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [SERIAL] ip22zilog: Whitespace cleanup.Ralf Baechle2006-02-081-0/+1
| | | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [SERIAL] uart_port iotype member should use UPIO_*Russell King2006-02-051-1/+1
| | | | | | Convert usage of SERIAL_IO_* to UPIO_*. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [PATCH] TTY layer buffering revampAlan Cox2006-01-101-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [SERIAL] dz: Use CKSEG1ADDR to setup mappings.Ralf Baechle2005-11-121-2/+2
| | | | | | | | | Use physical addresses at the interface level, letting drivers remap them as appropriate. Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [SERIAL] dz: Nuke trailing whitespaceRalf Baechle2005-11-121-22/+22
| | | | | Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* [SERIAL] Clean up and fix tty transmission start/stopingRussell King2005-08-311-5/+5
| | | | | | | | | | | | | | | | | | | | | | | The start_tx and stop_tx methods were passed a flag to indicate whether the start/stop was from the tty start/stop callbacks, and some drivers used this flag to decide whether to ask the UART to immediately stop transmission (where the UART supports such a feature.) There are other cases when we wish this to occur - when CTS is lowered, or if we change from soft to hard flow control and CTS is inactive. In these cases, this flag was false, and we would allow the transmitter to drain before stopping. There is really only one case where we want to let the transmitter drain before disabling, and that's when we run out of characters to send. Hence, re-jig the start_tx and stop_tx methods to eliminate this flag, and introduce new functions for the special "disable and allow transmitter to drain" case. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds2005-04-161-0/+822
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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