- 17 6月, 2011 1 次提交
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由 Shreshtha Kumar Sahu 提交于
This workaround aims to break the deadlock situation which raises during continuous transfer of data for long duration over uart with hardware flow control. It is observed that CTS interrupt cannot be cleared in uart interrupt register (ICR). Hence further transfer over uart gets blocked. It is seen that during such deadlock condition ICR don't get cleared even on multiple write. This leads pass_counter to decrease and finally reach zero. This can be taken as trigger point to run this UART_BT_WA. Workaround backups the register configuration, does soft reset of UART using BIT-0 of PRCC_K_SOFTRST_SET/CLEAR registers and restores the registers. This patch also provides support for uart init and exit function calls if present. Signed-off-by: NShreshtha Kumar Sahu <shreshthakumar.sahu@stericsson.com> Signed-off-by: NLinus Walleij <linus.walleij@linaro.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
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- 20 4月, 2011 1 次提交
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由 Jovi Zhang 提交于
remove invalid location line in each file header after location moved from driver/char to driver/tty Signed-off-by: NJovi Zhang <bookjovi@gmail.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
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- 31 3月, 2011 1 次提交
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由 Lucas De Marchi 提交于
Fixes generated by 'codespell' and manually reviewed. Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>
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- 10 3月, 2011 2 次提交
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由 Linus Walleij 提交于
This piece of code was just slightly different between the DMA and IRQ paths, in DMA mode we surely shouldn't read more than 256 character either, so factor this out in its own function and use for both DMA and PIO mode. Tested on Ux500 and U300. Signed-off-by: NLinus Walleij <linus.walleij@linaro.org> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Linus Walleij 提交于
This adds an optional RX DMA codepath for the devices that support this by using the apropriate burst sizes instead of pulling single bytes. Includes portions of code written by Russell King during a PL08x hacking session. This has been tested on U300 and Ux500. Tested-by: NJerzy Kasenberg <jerzy.kasenberg@tieto.com> Tested-by: NGrzegorz Sygieda <grzegorz.sygieda@tieto.com> Tested-by: NMarcin Mielczarczyk <marcin.mielczarczyk@tieto.com> Signed-off-by: NPer Forlin <per.friden@stericsson.com> Signed-off-by: NLinus Walleij <linus.walleij@linaro.org> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 24 2月, 2011 1 次提交
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由 Russell King 提交于
Make Primecell driver probe functions take a const pointer to their ID tables. Drivers should never modify their ID tables in their probe handler. Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 14 1月, 2011 1 次提交
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由 Greg Kroah-Hartman 提交于
The serial drivers are really just tty drivers, so move them to drivers/tty/ to make things a bit neater overall. This is part of the tty/serial driver movement proceedure as proposed by Arnd Bergmann and approved by everyone involved a number of months ago. Cc: Arnd Bergmann <arnd@arndb.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Rogier Wolff <R.E.Wolff@bitwizard.nl> Cc: Michael H. Warfield <mhw@wittsend.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
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- 06 1月, 2011 7 次提交
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由 Russell King 提交于
ST Micro variants has some specific dma burst threshold compensation, which allows them to make better use of a DMA controller. Add support to set this up. Based on a patch from Linus Walleij. Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Russell King 提交于
Add DMA engine support for transmit to the PL011 driver. Based on a patch from Linus Walliej, with the following changes: - remove RX DMA support. As PL011 doesn't give us receive timeout interrupts, we only get notified of received data when the RX DMA has completed. This rather sucks for interactive use of the TTY. - remove abuse of completions. Completions are supposed to be for events, not to tell what condition buffers are in. Replace it with a simple 'queued' bool. - fix locking - it is only safe to access the circular buffer with the port lock held. - only map the DMA buffer when required - if we're ever behind an IOMMU this helps keep IOMMU usage down, and also ensures that we're legal when we change the scatterlist entry length. - fix XON/XOFF sending - we must send XON/XOFF characters out as soon as possible - waiting for up to 4095 characters in the DMA buffer to be sent first is not acceptable. - fix XON/XOFF receive handling - we need to stop DMA when instructed to by the TTY layer, and restart it again when instructed to. There is a subtle problem here: we must not completely empty the circular buffer with DMA, otherwise we will not be notified of XON. - change the 'enable_dma' flag into a 'using DMA' flag, and track whether we can use TX DMA by whether the channel pointer is non-NULL. This gives us more control over whether we use DMA in the driver. - we don't need to have the TX DMA buffer continually allocated for each port - instead, allocate it when the port starts up, and free it when it's shut down. Update the 'using DMA' flag if we get the buffer, and adjust the TTY FIFO size appropriately. - if we're going to use PIO to send characters, use the existing IRQ based functionality rather than reimplementing it. This also ensures we call uart_write_wakeup() at the appropriate time, otherwise we'll stall. - use DMA engine helper functions for type safety. - fix init when built as a module - we can't have to initcall functions, so we must settle on one. This means we can eliminate the deferred DMA initialization. - there is no need to terminate transfers on a failed prep_slave_sg() call - nothing has been setup, so nothing needs to be terminated. This avoids a potential deadlock in the DMA engine code (tasklet->callback->failed prepare->terminate->tasklet_disable which then ends up waiting for the tasklet to finish running.) - Dan says that the submission callback should not return an error: | dma_submit_error() is something I should have removed after commit | a0587bcf "ioat1: move descriptor allocation from submit to prep" all | errors should be notified by prep failing to return a descriptor | handle. Negative dma_cookie_t values are only returned by the | dma_async_memcpy* calls which translate a prep failure into -ENOMEM. So remove the error handling at that point. This also solves the potential deadlock mentioned in the previous comment. Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Russell King 提交于
As the DMA support introduces a separate interrupt-time callback, our interrupt handler will not be the only handler which takes the port lock, so we need to ensure that IRQs are disabled. We must use the _irqsave variant so we don't inadvertently enable interrupts. Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Russell King 提交于
With DMA support, we need to tell the TTY subsystem that the DMA buffer is the size of the FIFO, otherwise things like tty_wait_until_sent() will time out too early. Keep (and use) the hardware value separately from the port->fifosize. This was part of a larger patch from Linus Walleij, with a little modification. Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Russell King 提交于
Rather than copying all vendor data into the port structure, copy just that which is frequently used, and keep a pointer to the remaining vendor data structure. This makes it easier to add vendor quirks in the future. Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Russell King 提交于
The error flags weren't being cleared upon UART startup, which can cause problems when we add DMA support. It's good practice to ensure that these flags are cleared anyway, so let's do so. This was part of a larger patch from Linus Walleij. Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Russell King 提交于
Include the revision number of the PL011 primecell in the boot-time port printk to allow proper identification of the peripheral. Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 27 7月, 2010 3 次提交
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由 Russell King 提交于
Found in the Versatile build: WARNING: drivers/built-in.o(.data+0x14c): Section mismatch in reference from the variable pl061_gpio_driver to the (unknown reference) .init.data:(unknown) The variable pl061_gpio_driver references the (unknown reference) __initdata (unknown) WARNING: drivers/built-in.o(.data+0x40f8): Section mismatch in reference from the variable pl011_driver to the (unknown reference) .init.data:(unknown) The variable pl011_driver references the (unknown reference) __initdata (unknown) WARNING: drivers/built-in.o(.data+0x5ab4): Section mismatch in reference from the variable pl031_driver to the (unknown reference) .init.data:(unknown) The variable pl031_driver references the (unknown reference) __initdata (unknown) Basically, amba_id structures must not be __initdata. Also fix: WARNING: drivers/built-in.o(.data+0x138): Section mismatch in reference from the variable pl061_gpio_driver to the function .init.text:pl061_probe() The variable pl061_gpio_driver references the function __init pl061_probe() which is an incorrectly annotated probe function. Fix it to reflect the other AMBA bus probe functions by removing the __init attributation. Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Linus Walleij 提交于
Implementation of the ST-Ericsson baudrate extension in the PL011 block. In this modified variant it is possible to change the sampling factor from 16 to 8, and thanks to this we can get higher baudrates while still using the same peripheral clock. Also replace the simple division to determine the baud divisor with DIV_ROUND_CLOSEST() rather than a simple integer division. Cc: Alessandro Rubini <rubini@unipv.it> Cc: Jerzy Kasenberg <jerzy.kasenberg@tieto.com> Signed-off-by: NMarcin Mielczarczyk <marcin.mielczarczyk@tieto.com> Signed-off-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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由 Linus Walleij 提交于
In the ST-Ericsson version of the PL011 the TX and RX have different control registers. Cc: Alessandro Rubini <rubini@unipv.it> Signed-off-by: NMarcin Mielczarczyk <marcin.mielczarczyk@tieto.com> Signed-off-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 21 5月, 2010 1 次提交
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由 Jason Wessel 提交于
The design of the kdb shell requires that every device that can provide input to kdb have a polling routine that exits immediately if there is no character available. This is required in order to get the page scrolling mechanism working. Changing the kernel debugger I/O API to require all polling character routines to exit immediately if there is no data allows the kernel debugger to process multiple input channels. NO_POLL_CHAR will be the return code to the polling routine when ever there is no character available. CC: linux-serial@vger.kernel.org Signed-off-by: NJason Wessel <jason.wessel@windriver.com>
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- 30 3月, 2010 1 次提交
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由 Tejun Heo 提交于
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: NTejun Heo <tj@kernel.org> Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
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- 19 2月, 2010 1 次提交
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由 Rabin Vincent 提交于
Enable/disable automatic hardware flow control as requested by the termios. The controller does not allow us to control the RTS line when auto-RTS is enabled, so we enable auto-RTS only if the kernel has not disabled RTS. Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRabin Vincent <rabin.vincent@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 20 9月, 2009 2 次提交
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由 Alan Cox 提交于
This is used by various drivers not just serial and can be extracted as commonality Signed-off-by: NAlan Cox <alan@linux.intel.com>
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由 Alan Cox 提交于
We moved this into uart_state, now move the fields out of the separate structure and kill it off. Signed-off-by: NAlan Cox <alan@linux.intel.com> Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
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- 02 9月, 2009 1 次提交
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由 Leo Chen 提交于
Add suspend/resume functions to the AMBA pl011 serial driver. Signed-off-by: NLeo Chen <leochen@broadcom.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 11 6月, 2009 1 次提交
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由 Linus Walleij 提交于
I found the PrimeCell/AMBA Bus drivers distrusting the resource passed in as part of the struct amba_device abstraction. This patch removes all hard coded resource sizes found in the PrimeCell drivers and move the responsibility of this definition back to the platform/board device definition, which already exist and appear to be correct for all in-tree users of these drivers. We do this using the resource_size() inline function which was also replicated in the only driver using the resource size, so that has been changed too. The KMI_SIZE was left in kmi.h in case someone likes it. Test-compiled against Versatile and Integrator defconfigs, seems to work but I don't posess these boards and cannot test them. Signed-off-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 05 6月, 2009 1 次提交
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由 Alessandro Rubini 提交于
The Nomadik 8815 SoC has a slightly modified version of the PL011 block. The patch uses the different ID value as a key to select a vendor structure that is used to keep track of the differences, as suggested by Russell King. Signed-off-by: NAlessandro Rubini <rubini@unipv.it> Acked-by: NAndrea Gallo <andrea.gallo@stericsson.com> Acked-by: NLinus Walleij <linus.walleij@stericsson.com> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 31 5月, 2009 1 次提交
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由 Alessandro Rubini 提交于
Signed-off-by: Alessandro Rubini <rubini@unipv.it>" Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 21 5月, 2009 1 次提交
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由 Alessandro Rubini 提交于
The second argument of the probe method points to the amba_id structure, so it's better passed with the correct type. None of the current in-tree drivers uses the pointer, so they have only been checked for a clean compile. Change suggested by Russell King. Signed-off-by: NAlessandro Rubini <rubini@unipv.it> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 01 12月, 2008 1 次提交
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由 Russell King 提交于
Where devices only have one consumer, passing a consumer clock ID has no real benefit, and it only encourages wrong implementations of the clk API. Remove it. Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 16 10月, 2008 1 次提交
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由 Yinghai Lu 提交于
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: NIngo Molnar <mingo@elte.hu>
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- 21 7月, 2008 2 次提交
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由 Takashi Iwai 提交于
The below is the patch to replace blindly all possible places, including Jack's fixes. Signed-off-by: NTakashi Iwai <tiwai@suse.de> (Reviewed and checked rather than blindly added) Signed-off-by: NAlan Cox <alan@redhat.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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由 Adrian Bunk 提交于
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: NAdrian Bunk <bunk@kernel.org> Signed-off-by: NAlan Cox <alan@redhat.com> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 18 4月, 2008 1 次提交
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由 Jason Wessel 提交于
Implement the serial polling hooks for the pl011 uart for use with kgdboc. This patch was specifically tested on the ARM Versatile AB reference platform. [ mingo@elte.hu: minor cleanups. ] Signed-off-by: NJason Wessel <jason.wessel@windriver.com> Signed-off-by: NIngo Molnar <mingo@elte.hu> Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
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- 20 10月, 2007 1 次提交
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由 Jiri Slaby 提交于
amba-pl011, rename BIT macro Signed-off-by: NJiri Slaby <jirislaby@gmail.com> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 20 7月, 2007 1 次提交
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由 Yoann Padioleau 提交于
Transform some calls to kmalloc/memset to a single kzalloc (or kcalloc). Here is a short excerpt of the semantic patch performing this transformation: @@ type T2; expression x; identifier f,fld; expression E; expression E1,E2; expression e1,e2,e3,y; statement S; @@ x = - kmalloc + kzalloc (E1,E2) ... when != \(x->fld=E;\|y=f(...,x,...);\|f(...,x,...);\|x=E;\|while(...) S\|for(e1;e2;e3) S\) - memset((T2)x,0,E1); @@ expression E1,E2,E3; @@ - kzalloc(E1 * E2,E3) + kcalloc(E1,E2,E3) [akpm@linux-foundation.org: get kcalloc args the right way around] Signed-off-by: NYoann Padioleau <padator@wanadoo.fr> Cc: Richard Henderson <rth@twiddle.net> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Acked-by: NRussell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <bryan.wu@analog.com> Acked-by: NJiri Slaby <jirislaby@gmail.com> Cc: Dave Airlie <airlied@linux.ie> Acked-by: NRoland Dreier <rolandd@cisco.com> Cc: Jiri Kosina <jkosina@suse.cz> Acked-by: NDmitry Torokhov <dtor@mail.ru> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Acked-by: NMauro Carvalho Chehab <mchehab@infradead.org> Acked-by: NPierre Ossman <drzeus-list@drzeus.cx> Cc: Jeff Garzik <jeff@garzik.org> Cc: "David S. Miller" <davem@davemloft.net> Acked-by: NGreg KH <greg@kroah.com> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: NAndrew Morton <akpm@linux-foundation.org> Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
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- 30 5月, 2007 1 次提交
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由 Thomas Gleixner 提交于
The -rt patch triggered a lockdep warning in the amba serial drivers, which never shows up on UP kernels. On SMP systems this would trigger as well. Release the port lock before calling tty_flip_buffer_push() and reacquire it after the call. This matches the code in the 8250 serial driver. Signed-off-by: NThomas Gleixner <tglx@linutronix.de> Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 24 1月, 2007 1 次提交
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由 Russell King 提交于
Using console=ttyAM1 or console=ttyAMA1 resulted in an oops during boot due to trying to drive the console before that port had been registered. Fix this by checking whether the port is present before allowing console setup to proceed. Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
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- 09 12月, 2006 1 次提交
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由 Alan Cox 提交于
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: NAlan Cox <alan@redhat.com> Signed-off-by: NMartin Peschke <mp3@de.ibm.com> Acked-by: NPeter Oberparleiter <oberpar@de.ibm.com> Cc: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: NHugh Dickins <hugh@veritas.com> Signed-off-by: NJeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: NAndrew Morton <akpm@osdl.org> Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
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- 05 10月, 2006 1 次提交
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由 David Howells 提交于
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: NDavid Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
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- 01 7月, 2006 1 次提交
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由 Jörn Engel 提交于
Signed-off-by: NJörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: NAdrian Bunk <bunk@stusta.de>
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- 21 3月, 2006 1 次提交
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由 Russell King 提交于
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: NRussell King <rmk+kernel@arm.linux.org.uk>
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