aboutsummaryrefslogtreecommitdiff
path: root/drivers/serial/8250.c
AgeCommit message (Collapse)Author
2009-06-11serial: add support for the TI AR7 internal UARTFlorian Fainelli
This patch adds support for the TI AR7 internal UART. Signed-off-by: Florian Fainelli <florian@openwrt.org> Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-298250: Fix oops from setserialAlan Cox
If you setserial a port which has never been initialised we change the type but don't update the I/O method pointers. The same problem is true if you change the io type of a port - but nobody ever does that so nobody noticed! Remember the old type and when attaching if the type has changed reload the port accessor pointers. We can't do it blindly as some 8250 drivers load custom accessors and we must not stomp those. Tested-by: Victor Seryodkin <vvscore@gmail.com> Closes-bug: #13367 Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-02-208250: fix boot hang with serial console when using with Serial Over Lan portMauro Carvalho Chehab
Intel 8257x Ethernet boards have a feature called Serial Over Lan. This feature works by emulating a serial port, and it is detected by kernel as a normal 8250 port. However, this emulation is not perfect, as also noticed on changeset 7500b1f602aad75901774a67a687ee985d85893f. Before this patch, the kernel were trying to check if the serial TX is capable of work using IRQ's. This were done with a code similar this: serial_outp(up, UART_IER, UART_IER_THRI); lsr = serial_in(up, UART_LSR); iir = serial_in(up, UART_IIR); serial_outp(up, UART_IER, 0); if (lsr & UART_LSR_TEMT && iir & UART_IIR_NO_INT) up->bugs |= UART_BUG_TXEN; This works fine for other 8250 ports, but, on 8250-emulated SoL port, the chip is a little lazy to down UART_IIR_NO_INT at UART_IIR register. Due to that, UART_BUG_TXEN is sometimes enabled. However, as TX IRQ keeps working, and the TX polling is now enabled, the driver miss-interprets the IRQ received later, hanging up the machine until a key is pressed at the serial console. This is the 6 version of this patch. Previous versions were trying to introduce a large enough delay between serial_outp and serial_in(up, UART_IIR), but not taking forever. However, the needed delay couldn't be safely determined. At the experimental tests, a delay of 1us solves most of the cases, but still hangs sometimes. Increasing the delay to 5us was better, but still doesn't solve. A very high delay of 50 ms seemed to work every time. However, poking around with delays and pray for it to be enough doesn't seem to be a good approach, even for a quirk. So, instead of playing with random large arbitrary delays, let's just disable UART_BUG_TXEN for all SoL ports. [akpm@linux-foundation.org: fix warnings] Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-13fix early_serial_setup() regressionHelge Deller
Commit b430428a188e8a434325e251d0704af4b88b4711 ("8250: Don't clobber spinlocks.") introduced a regression on the parisc architecture, which broke the handover to the serial port at boottime. early_serial_setup() was changed to only copy a subset of the uart_port fields, and sadly the "type" and "line" fields were forgotten and thus the serial port was not initialized and could not be used for a handover. This patch fixes this by copying the missing fields. As this change to early_serial_setup() doesn't need an initialized spinlock in the uart_port struct any longer, we can drop the spinlock initialization in the superio driver. Cc: David Daney <ddaney@caviumnetworks.com> Cc: Tomaso Paoletti <tpaoletti@caviumnetworks.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Acked-by: Kyle McMartin <kyle@mcmartin.ca> Cc: linux-parisc@vger.kernel.org Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06trivial: Add a space (and a comma) to a printk in 8250 driverPaul Bolle
Commit d87a6d9 ("drivers/serial/: remove CVS keywords") removed one space too many in the printk in serial8250_init(). Put it back in (and add a comma for clarity). Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2009-01-02Serial: UART driver changes for Cavium OCTEON.David Daney
Cavium UART implementation is not covered by existing uart_configS. Define a new uart_config (PORT_OCTEON) which is specified by OCTEON platform device registration code. Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com> Signed-off-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-02Serial: Allow port type to be specified when calling serial8250_register_port.David Daney
Add flag value UPF_FIXED_TYPE which specifies that the UART type is known and should not be probed. For this case the UARTs properties are just copied out of the uart_config entry. This allows us to keep SOC specific 8250 probe code out of 8250.c. In this case we know the serial hardware will not be changing as it is on the same silicon as the CPU, and we can specify it with certainty in the board/cpu setup code. The alternative is to load up 8250.c with a bunch of OCTEON specific special cases in the probing code. Signed-off-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-028250: Serial driver changes to support future Cavium OCTEON serial patches.David Daney
In order to use Cavium OCTEON specific serial i/o drivers, we first patch the 8250 driver to use replaceable I/O functions. Compatible I/O functions are added for existing iotypeS. An added benefit of this change is that it makes it easy to factor some of the existing special cases out to board/SOC specific support code. The alternative is to load up 8250.c with a bunch of OCTEON specific iotype code and bug work-arounds. Signed-off-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-028250: Don't clobber spinlocks.David Daney
In serial8250_isa_init_ports(), the port's lock is initialized. We should not overwrite it. In early_serial_setup(), only copy in the fields we need. Since the early console code only uses a subset of the fields, these are sufficient. Signed-off-by: David Daney <ddaney@caviumnetworks.com> Signed-off-by: Tomaso Paoletti <tpaoletti@caviumnetworks.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20Merge branch 'genirq-v28-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip This merges branches irq/genirq, irq/sparseirq-v4, timers/hpet-percpu and x86/uv. The sparseirq branch is just preliminary groundwork: no sparse IRQs are actually implemented by this tree anymore - just the new APIs are added while keeping the old way intact as well (the new APIs map 1:1 to irq_desc[]). The 'real' sparse IRQ support will then be a relatively small patch ontop of this - with a v2.6.29 merge target. * 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (178 commits) genirq: improve include files intr_remapping: fix typo io_apic: make irq_mis_count available on 64-bit too genirq: fix name space collisions of nr_irqs in arch/* genirq: fix name space collision of nr_irqs in autoprobe.c genirq: use iterators for irq_desc loops proc: fixup irq iterator genirq: add reverse iterator for irq_desc x86: move ack_bad_irq() to irq.c x86: unify show_interrupts() and proc helpers x86: cleanup show_interrupts genirq: cleanup the sparseirq modifications genirq: remove artifacts from sparseirq removal genirq: revert dynarray genirq: remove irq_to_desc_alloc genirq: remove sparse irq code genirq: use inline function for irq_to_desc genirq: consolidate nr_irqs and for_each_irq_desc() x86: remove sparse irq from Kconfig genirq: define nr_irqs for architectures with GENERIC_HARDIRQS=n ...
2008-10-16Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (51 commits) [ARM] 5308/1: Fix Viper ISA IRQ handling [ARM] 5307/1: pxa: fix CM-X2XX PCMCIA build error [ARM] 5306/1: pxa: fix build error on CM-X270 [ARM] 5302/1: ARM: OMAP: Revert omap3 WDT changes to avoid merge conflict [ARM] 5305/1: ARM: OMAP: Fix compile of McBSP by removing unnecessary check [ARM] 5301/1: ARM: OMAP: Add missing irq defines ARM: OMAP3: Add default kernel config for OMAP LDP ARM: OMAP3: Add basic board support for OMAP LDP ARM: OMAP3: Defconfig for the Gumstix Overo board (rev 3) ARM: OMAP3: Add support for the Gumstix Overo board (rev 3) ARM: OMAP3: Add Beagle defconfig ARM: OMAP3: Add minimal Beagle board support ARM: OMAP3: Add minimal omap3430 support ARM: OMAP2: Fix sparse, checkpatch warnings in OMAP2/3 IRQ code ARM: OMAP: Fixes to omap_mcbsp_request function ARM: OMAP: Add support for OMAP2430 in McBSP ARM: OMAP: Add support for McBSP devices 3 - 5 on 34xx ARM: OMAP: Allocate McBSP devices dynamically Fix sections for omap-mcbsp platform driver [ARM] S3C24XX: Additional include moves ...
2008-10-16drivers/serial: use nr_irqsYinghai Lu
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-16serial, 8250: remove NR_IRQ usageAlan Cox
Works on my test box with a quick test. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-10-15Merge branch 'fixes' into for-linusRussell King
Conflicts: arch/arm/mach-versatile/core.c
2008-10-148250: Fix lock warning (and possible crash)Alan Cox
Splitting the 8250 code back up to avoid a clash with the NR_IRQS removal patch introduced a last minute bug. Put back the additional needed lines for the old lock init Signed-off-by: Alan Cox <alan@redhat.com> [ Ingo also reports that this can cause a spontaneous reboot crash with certain configs, and sends in an identical patch ] Tested-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13serial: fix device name reporting when minor space is shared between driversDavid S. Miller
The multiple drivers share the minor space occupied by a particular major number, the actual index within the device name's space is indicated by the tty_driver->name_base + uart_port->line Another usable formula is (uart_driver->minor - MINOR_BASE) + port->line Use those to print the device names properly in such situations in serial_core.c and 8250.c Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13serial: allow 8250 to be used on sparcDavid Miller
This requires three changes: 1) Remove !SPARC restriction in Kconfig. 2) Move Sparc specific serial drivers before 8250, so that serial console devices don't change names on us, even if 8250 finds devices. 3) Since the Sparc specific serial drivers try to use the same major/minor device namespace as 8250, some coordination is necessary. Use the sunserial_*() layer routines to allocate minor number space within TTY_MAJOR when CONFIG_SPARC. This has no effect on other platforms. Thanks to Josip Rodin for bringing up this issue and testing plus debugging various revisions of this patch. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-138250: remove a few inlines of dubious valueWill Newton
Remove some inlines from various functions that are called once, are too big to inline, or are called only from slow path code. This saves around 300 bytes of code for me. Signed-off-by: Will Newton <will.newton@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-09-05[SERIAL] 8250: serial8250_port_size() - omap ports are largerRussell King
A function to contain common code for the size of the resource we need to allocate or free. OMAP ports need 22 bytes rather than the standard 8 bytes. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-05[ARM] omap: improve is_omap_port()Russell King
Make is_omap_port() take the uart_8250_port structure so it can do whatever test it desires. Convert the test to compare the physical addresses rather than virtual addresses. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-09-028250: improve workaround for UARTs that don't re-assert THRE correctlyWill Newton
Recent changes to tighten the check for UARTs that don't correctly re-assert THRE (01c194d9278efc15d4785ff205643e9c0bdcef53: "serial 8250: tighten test for using backup timer") caused problems when such a UART was opened for the second time - the bug could only successfully be detected at first initialization. For users of this version of this particular UART IP it is fatal. This patch stores the information about the bug in the bugs field of the port structure when the port is first started up so subsequent opens can check this bit even if the test for the bug fails. David Brownell: "My own exposure to this is that the UART on DaVinci hardware, which TI allegedly derived from its original 16550 logic, has periodically gone from working to unusable with the mainline 8250.c ... and back and forth a bunch. Currently it's "unusable", a regression from some previous versions. With this patch from Will, it's usable." Signed-off-by: Will Newton <will.newton@gmail.com> Acked-by: Alex Williamson <alex.williamson@hp.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: David Brownell <david-b@pacbell.net> Cc: <stable@kernel.org> [2.6.26.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-308250.c: port.lock is irq-safeBorislav Petkov
serial8250_startup() doesn't disable interrupts while taking the &up->port.lock which might race against the interrupt handler serial8250_interrupt(), which when entered, will deadlock waiting for the lock to be released. Signed-off-by: Borislav Petkov <petkovbb@gmail.com> Tested-by: Ingo Molnar <mingo@elte.hu> 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>
2008-07-248250: fix break handling for Intel 82571Aristeu Rozanski
Intel 82571 has a "Serial Over LAN" feature that doesn't properly implements the receiving of break characters. When a break is received, it doesn't set UART_LSR_DR and unless another character is received, the break won't be received by the application. Signed-off-by: Aristeu Rozanski <arozansk@redhat.com> Acked-by: 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>
2008-07-22serial: 8250: fix shared interrupts issues with SMP and RT kernelsAnton Vorontsov
With SMP kernels _irqsave spinlock disables only local interrupts, while the shared serial interrupt could be assigned to the CPU that is not currently starting up the serial port. This might cause issues because serial8250_startup() routine issues IRQ-triggering operations before registering the port in the IRQ chain (though, this is fine to do and done explicitly because we don't want to process any interrupts on the port startup). With RT kernels and preemptable hardirqs, _irqsave spinlock does not disable local hardirqs, and the bug could be reproduced much easily: $ cat /dev/ttyS0 & $ cat /dev/ttyS1 irq 42: nobody cared (try booting with the "irqpoll" option) Call Trace: [C0475EB0] [C0008A98] show_stack+0x4c/0x1ac (unreliable) [C0475EF0] [C004BBD4] __report_bad_irq+0x34/0xb8 [C0475F10] [C004BD38] note_interrupt+0xe0/0x308 [C0475F50] [C004B09C] thread_simple_irq+0xdc/0x104 [C0475F70] [C004B3FC] do_irqd+0x338/0x3c8 [C0475FC0] [C00398E0] kthread+0xf8/0x100 [C0475FF0] [C0011FE0] original_kernel_thread+0x44/0x60 handlers: [<c02112c4>] (serial8250_interrupt+0x0/0x138) Disabling IRQ #42 After this, all serial ports on the given IRQ are non-functional. To fix the issue we should explicitly disable shared IRQ before issuing any IRQ-triggering operations. I also changed spin_lock_irqsave to the ordinary spin_lock, since it seems to be safe: chain does not contain new port (yet), thus nobody will interfere us from the ISRs. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-20serial: use tty_portAlan Cox
Switch the serial_core based drivers to use the new tty_port structure. We can't quite use all of it yet because of the dynamically allocated extras in the serial_core layer. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-20drivers/serial/: remove CVS keywordsAdrian Bunk
This patch removes CVS keywords that weren't updated for a long time in comments, printk's and MODULE_DESCRIPTION's (no printk's or MODULE_DESCRIPTION's are completely removed). While doing this I also found and fixed a missing \n in a printk in m32r_sio.c Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-12serial8250: sanity check nr_uarts on all paths.Eric W. Biederman
I had 8250.nr_uarts=16 in the boot line of a test kernel and I had a weird mysterious crash in sysfs. After taking an in-depth look I realized that CONFIG_SERIAL_8250_NR_UARTS was set to 4 and I was walking off the end of the serial8250_ports array. Ouch!!! Don't let this happen to someone else. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Alan Cox <alan@redhat.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-318250 Serial Driver: revert extra IRQ flag definition patchBryan Wu
As Russell pointed out, original patch will break some serial configurations because of the dependency of the <asm/serial.h> header file. Revert it first and try to find out other solution later Cc: Javier Herrero <jherrero@hvsistemas.es> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Russell King <rmk+lkml@arm.linux.org.uk> Signed-off-by: Bryan Wu <cooloney@kernel.org>
2008-05-178250 Serial Driver: Added support for 8250-class UARTs in HV Sistemas H8606 ↵Javier Herrero
board Added support for 8250-class UARTs in HV Sistemas H8606 board, modification in 8250.c driver for correct compilation with Blackfin Besides, I think that there is more people using 8250-class UARTs with a different hardware than the H8606 board. This code can be shared by them. Signed-off-by: Javier Herrero <jherrero@hvsistemas.es> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Signed-off-by: Bryan Wu <cooloney@kernel.org>
2008-05-018250: switch 8250 drivers to use _nocache ioremapsAlan Cox
Signed-off-by: Alan Cox <alan@redhat.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28serial 8250: tighten test for using backup timerAlex Williamson
Thomas Koeller had reported an issue where a device that had been making use of the UART_BUG_TXEN code in the 8250 driver was mistakenly being caught by the backup timer test, causing the device to work improperly. To fix this, tighten the test requirements to enable the backup timer workaround. The backup timer is really meant to catch UARTs that don't re-assert the THRE interrupt. The expectation is that they do initially assert THRE. This patch clarifies the test. Signed-off-by: Alex Williamson <alex.williamson@hp.com> Cc: Thomas Koeller <thomas@koeller.dyndns.org> Cc: Russell King <rmk@arm.linux.org.uk> 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>
2008-04-28Fix tty speed handling on 8250Alan Cox
We try and write the correct speed back but the serial midlayer already mangles the speed on us and that means if we request B0 we report back B9600 when we should not. For now we'll hack around this in the drivers and serial code, pending a better long term solution. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-17consoles: polling support, kgdbocJason Wessel
polled console handling support, to access a console in an irq-less way while in debug or irq context. absolutely zero impact as long as CONFIG_CONSOLE_POLL is disabled. (which is the default) [ jan.kiszka@siemens.com: lots of cleanups ] [ mingo@elte.hu: redesign, splitups, cleanups. ] Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Jan Kiszka <jan.kiszka@web.de> Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
2008-02-088250: enable rate reporting via termiosAlan Cox
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08serial8250: coding styleAlan Cox
Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05serial: Coding styleAlan Cox
Coding style tweaks and printk levels. Signed-off-by: Alan Cox <alan@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-058250.c: support specifying DW APB UARTs in device platform_dataWill Newton
Allow the private_data field to be specified in platform_data for the standard 8250/16550 UART. This field is used by DW APB type UARTs and without this patch it's only possible to set this field when registering the port by hand. If private_data is not set then the driver will potentially oops with a NULL pointer dereference. Signed-off-by: Will Newton <will.newton@gmail.com> Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-08-22Serial 8250: handle saving the clear-on-read bits from the LSR and MSRCorey Minyard
Reading the LSR clears the break, parity, frame error, and overrun bits in the 8250 chip, but these are not being saved in all places that read the LSR. Same goes for the MSR delta bits. Save the LSR bits off whenever the lsr is read so they can be handled later in the receive routine. Save the MSR bits to be handled in the modem status routine. Also, clear the stored bits and clear the interrupt registers before enabling interrupts, to avoid handling old values of the stored bits in the interrupt routines. [akpm@linux-foundation.org: clean up pre-existing code] Signed-off-by: Corey Minyard <minyard@acm.org> Cc: Russell King <rmk+lkml@arm.linux.org.uk> Cc: Yinghai Lu <yinghai.lu@sun.com> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Acked-by: 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>
2007-08-03serial: fix 8250 early console setupDaniel Ritz
the early setup function serial8250_console_early_setup() can be called from non __init code (eg. hotpluggable serial ports like serial_cs) so remove the __init from the call chain to avoid crashes. Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch> Cc: Yinghai Lu <yinghai.lu@sun.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-24Use resource_size_t for serial port IO addressesJosh Boyer
At present, various parts of the serial code use unsigned long to define resource addresses. This is a problem, because some 32-bit platforms have physical addresses larger than 32-bits, and have mmio serial uarts located above the 4GB point. This patch changes the type of mapbase in both struct uart_port and struct plat_serial8250_port to resource_size_t, which can be configured to be 64 bits on such platforms. The mapbase in serial_struct can't safely be changed, because that structure is user visible. Signed-off-by: David Gibson <dwg@au1.ibm.com> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Paul Mackerras <paulus@samba.org> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16serial: convert early_uart to earlycon for 8250Yinghai Lu
Beacuse SERIAL_PORT_DFNS is removed from include/asm-i386/serial.h and include/asm-x86_64/serial.h. the serial8250_ports need to be probed late in serial initializing stage. the console_init=>serial8250_console_init=> register_console=>serial8250_console_setup will return -ENDEV, and console ttyS0 can not be enabled at that time. need to wait till uart_add_one_port in drivers/serial/serial_core.c to call register_console to get console ttyS0. that is too late. Make early_uart to use early_param, so uart console can be used earlier. Make it to be bootconsole with CON_BOOT flag, so can use console handover feature. and it will switch to corresponding normal serial console automatically. new command line will be: console=uart8250,io,0x3f8,9600n8 console=uart8250,mmio,0xff5e0000,115200n8 or earlycon=uart8250,io,0x3f8,9600n8 earlycon=uart8250,mmio,0xff5e0000,115200n8 it will print in very early stage: Early serial console at I/O port 0x3f8 (options '9600n8') console [uart0] enabled later for console it will print: console handover: boot [uart0] -> real [ttyS0] Signed-off-by: <yinghai.lu@sun.com> Cc: Andi Kleen <ak@suse.de> Cc: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Gerd Hoffmann <kraxel@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-17NS16550A: Restore HS settings in EXCR2 on resumeDavid Woodhouse
After a suspend/resume cycle, the UART may have been reset into low-speed mode -- either because it's actually been reset, or because the firmware pokes at the old-style divisor registers. If we detected it as a NS16550A SuperIO chip in the first place and set baud_base to 921600, then we should do so again in the resume path. This patch adds that code to serial8250_resume_port(), and also makes serial8250_resume() actually call serial8250_resume_port() for each port instead of just calling uart_resume_port() directly. And thus fixes serial port operation after suspend/resume. It also fixes a bogus comment where we write the EXCR2 register with a comment saying /* EXCR1 */ Signed-off-by: David Woodhouse <dwmw2@infradead.org> Acked-by: Alan Cox <alan@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-088250: Remove commented out irq cruftJosh Boyer
Remove some obviously old interrupt disable/enable code that has been commented out. Signed-off-by: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07RM9000 serial driverThomas Koeller
Add support for the integrated serial ports of the MIPS RM9122 processor and its relatives. The patch also does some whitespace cleanup. [akpm@linux-foundation.org: cleanups] Signed-off-by: Thomas Koeller <thomas.koeller@baslerweb.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Russell King <rmk@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-07serial driver PMC MSP71xxMarc St-Jean
Serial driver patch for the PMC-Sierra MSP71xx devices. There are three different fixes: 1 Fix for DesignWare APB THRE errata: In brief, this is a non-standard 16550 in that the THRE interrupt will not re-assert itself simply by disabling and re-enabling the THRI bit in the IER, it is only re-enabled if a character is actually sent out. It appears that the "8250-uart-backup-timer.patch" in the "mm" tree also fixes it so we have dropped our initial workaround. This patch now needs to be applied on top of that "mm" patch. 2 Fix for Busy Detect on LCR write: The DesignWare APB UART has a feature which causes a new Busy Detect interrupt to be generated if it's busy when the LCR is written. This fix saves the value of the LCR and rewrites it after clearing the interrupt. 3 Workaround for interrupt/data concurrency issue: The SoC needs to ensure that writes that can cause interrupts to be cleared reach the UART before returning from the ISR. This fix reads a non-destructive register on the UART so the read transaction completion ensures the previously queued write transaction has also completed. Signed-off-by: Marc St-Jean <Marc_St-Jean@pmc-sierra.com> Cc: Russell King <rmk@arm.linux.org.uk> 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>
2007-04-248250: fix possible deadlock between serial8250_handle_port() and ↵Jiri Kosina
serial8250_interrupt() Commit 40b36daa introduced possibility that serial8250_backup_timeout() -> serial8250_handle_port() locks port.lock without disabling irqs, thus allowing deadlock against interrupt handler (port.lock is acquired in serial8250_interrupt()). Spotted by lockdep. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Cc: Dave Jones <davej@codemonkey.org.uk> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Alex Williamson <alex.williamson@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-04-24Fix possible NULL pointer access in 8250 serial driverTaku Izumi
I encountered the following kernel panic. The cause of this problem was NULL pointer access in check_modem_status() in 8250.c. I confirmed this problem is fixed by the attached patch, but I don't know this is the correct fix. sadc[4378]: NaT consumption 2216203124768 [1] Modules linked in: binfmt_misc dm_mirror dm_mod thermal processor fan container button sg e100 eepro100 mii ehci_hcd ohci_hcd Pid: 4378, CPU 0, comm: sadc psr : 00001210085a2010 ifs : 8000000000000289 ip : [<a000000100482071>] Not tainted ip is at check_modem_status+0xf1/0x360 Call Trace: [<a000000100013940>] show_stack+0x40/0xa0 [<a0000001000145a0>] show_regs+0x840/0x880 [<a0000001000368e0>] die+0x1c0/0x2c0 [<a000000100036a30>] die_if_kernel+0x50/0x80 [<a000000100037c40>] ia64_fault+0x11e0/0x1300 [<a00000010000bdc0>] ia64_leave_kernel+0x0/0x280 [<a000000100482070>] check_modem_status+0xf0/0x360 [<a000000100482300>] serial8250_get_mctrl+0x20/0xa0 [<a000000100478170>] uart_read_proc+0x250/0x860 [<a0000001001c16d0>] proc_file_read+0x1d0/0x4c0 [<a0000001001394b0>] vfs_read+0x1b0/0x300 [<a000000100139cd0>] sys_read+0x70/0xe0 [<a00000010000bc20>] ia64_ret_from_syscall+0x0/0x20 [<a000000000010620>] __kernel_syscall_via_break+0x0/0x20 Fix the possible NULL pointer access in check_modem_status() in 8250.c. The check_modem_status() would access 'info' member of uart_port structure, but it is not initialized before uart_open() is called. The check_modem_status() can be called through /proc/tty/driver/serial before uart_open() is called. Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> Signed-off-by: Taku Izumi <izumi2005@soft.fujitsu.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-20[PATCH] 8250: Fix GCC4 signed/unsigned mismatch warningThomas Koeller
Signed-off-by: Thomas Koeller <thomas.koeller@baslerweb.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-14[PATCH] 8250 UART backup timerAlex Williamson
The patch below works around a minor bug found in the UART of the remote management card used in many HP ia64 and parisc servers (aka the Diva UARTs). The problem is that the UART does not reassert the THRE interrupt if it has been previously cleared and the IIR THRI bit is re-enabled. This can produce a very annoying failure mode when used as a serial console, allowing a boot/reboot to hang indefinitely until an RX interrupt kicks it into working again (ie. an unattended reboot could stall). To solve this problem, a backup timer is introduced that runs alongside the standard interrupt driven mechanism. This timer wakes up periodically, checks for a hang condition and gets characters moving again. This backup mechanism is only enabled if the UART is detected as having this problem, so systems without these UARTs will have no additional overhead. This version of the patch incorporates previous comments from Pavel and removes races in the bug detection code. The test is now done before the irq linking to prevent races with interrupt handler clearing the THRE interrupt. Short delays and syncs are also added to ensure the device is able to update register state before the result is tested. Aristeu says: this was tested on the following HP machines and solved the problem: rx2600, rx2620, rx1600 and rx1620s. hpa says: I have seen this same bug in soft UART IP from "a major vendor." Signed-off-by: Alex Williamson <alex.williamson@hp.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Russell King <rmk@arm.linux.org.uk> Acked-by: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] Perle multimodem card (PCI-RAS) detectionThomas Hoehn
Get the Perle quad-modem PCI card (PCI-RAS4) detected by serial driver. It may also get the PCI-RAS8 running, but can't guarantee as I didn't had one for testing. Signed-off-by: Thomas Hoehn <thomas.hoehn@avocent.com> Cc: Russell King <rmk@arm.linux.org.uk> 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>