linux-stable.git/drivers/i2c, branch linux-3.19.y Linux kernel stable tree i2c: core: Export bus recovery functions 2015-05-06T20:02:01+00:00 Mark Brown broonie@kernel.org 2015-04-15T18:18:39+00:00 0bc7e7404e441922083bdee22c0b75f46b5a3fc0 commit c1c21f4e60ed4523292f1a89ff45a208bddd3849 upstream. Current -next fails to link an ARM allmodconfig because drivers that use the core recovery functions can be built as modules but those functions are not exported: ERROR: "i2c_generic_gpio_recovery" [drivers/i2c/busses/i2c-davinci.ko] undefined! ERROR: "i2c_generic_scl_recovery" [drivers/i2c/busses/i2c-davinci.ko] undefined! ERROR: "i2c_recover_bus" [drivers/i2c/busses/i2c-davinci.ko] undefined! Add exports to fix this. Fixes: 5f9296ba21b3c (i2c: Add bus recovery infrastructure) Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c1c21f4e60ed4523292f1a89ff45a208bddd3849 upstream.

Current -next fails to link an ARM allmodconfig because drivers that use
the core recovery functions can be built as modules but those functions
are not exported:

ERROR: "i2c_generic_gpio_recovery" [drivers/i2c/busses/i2c-davinci.ko] undefined!
ERROR: "i2c_generic_scl_recovery" [drivers/i2c/busses/i2c-davinci.ko] undefined!
ERROR: "i2c_recover_bus" [drivers/i2c/busses/i2c-davinci.ko] undefined!

Add exports to fix this.

Fixes: 5f9296ba21b3c (i2c: Add bus recovery infrastructure)
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
i2c: rk3x: report number of messages transmitted 2015-05-06T20:02:01+00:00 Dmitry Torokhov dmitry.torokhov@gmail.com 2015-04-20T22:14:47+00:00 a0525be6dc515578a68d11a6938e96d68a70014f commit c6cbfb91b878224e78408a2e15901c79de77115a upstream. master_xfer() method should return number of i2c messages transferred, but on Rockchip we were usually returning just 1, which caused trouble with users that actually check number of transferred messages vs. checking for negative error codes. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c6cbfb91b878224e78408a2e15901c79de77115a upstream.

master_xfer() method should return number of i2c messages transferred,
but on Rockchip we were usually returning just 1, which caused trouble
with users that actually check number of transferred messages vs.
checking for negative error codes.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
i2c: mux: use proper dev when removing "channel-X" symlinks 2015-05-06T20:02:00+00:00 Wolfram Sang wsa+renesas@sang-engineering.com 2015-04-23T08:29:09+00:00 7c897ccd3c9865b879c7bf970423e365dad1f1ab commit 133778482ec6c8fde69406be380333963627c17a upstream. Those symlinks are created for the mux_dev, so we need to remove it from there. Currently, it breaks for muxes where the mux_dev is not the device of the parent adapter like this: [ 78.234644] WARNING: CPU: 0 PID: 365 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x5c/0x78() [ 78.242438] sysfs: cannot create duplicate filename '/devices/platform/i2cbus@8/channel-0' Remove confusing comments while we are here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Fixes: c9449affad2ae0 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 133778482ec6c8fde69406be380333963627c17a upstream.

Those symlinks are created for the mux_dev, so we need to remove it from
there. Currently, it breaks for muxes where the mux_dev is not the device
of the parent adapter like this:

[   78.234644] WARNING: CPU: 0 PID: 365 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x5c/0x78()
[   78.242438] sysfs: cannot create duplicate filename '/devices/platform/i2cbus@8/channel-0'

Remove confusing comments while we are here.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: c9449affad2ae0
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Revert "i2c: core: Dispose OF IRQ mapping at client removal time" 2015-03-26T12:59:45+00:00 Jakub Kicinski kubakici@wp.pl 2015-03-11T17:35:36+00:00 15f3667aa26cb5884cb6a1b9d1ba069be440ee66 commit a49445727014216703a3c28ccee4cef36d41571e upstream. This reverts commit e4df3a0b6228 ("i2c: core: Dispose OF IRQ mapping at client removal time") Calling irq_dispose_mapping() will destroy the mapping and disassociate the IRQ from the IRQ chip to which it belongs. Keeping it is OK, because existent mappings are reused properly. Also, this commit breaks drivers using devm* for IRQ management on OF-based systems because devm* cleanup happens in device code, after bus's remove() method returns. Signed-off-by: Jakub Kicinski <kubakici@wp.pl> Reported-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> [wsa: updated the commit message with findings fromt the other bug report] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Fixes: e4df3a0b6228 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit a49445727014216703a3c28ccee4cef36d41571e upstream.

This reverts commit e4df3a0b6228
("i2c: core: Dispose OF IRQ mapping at client removal time")

Calling irq_dispose_mapping() will destroy the mapping and disassociate
the IRQ from the IRQ chip to which it belongs. Keeping it is OK, because
existent mappings are reused properly.

Also, this commit breaks drivers using devm* for IRQ management on
OF-based systems because devm* cleanup happens in device code, after
bus's remove() method returns.

Signed-off-by: Jakub Kicinski <kubakici@wp.pl>
Reported-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
[wsa: updated the commit message with findings fromt the other bug report]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: e4df3a0b6228
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
i2c: sh_mobile: terminate DMA reads properly 2015-01-30T16:58:43+00:00 Wolfram Sang wsa+renesas@sang-engineering.com 2015-01-29T17:33:16+00:00 32e224090fa310a58fdb47049caf631272ceb044 DMA read requests could miss proper termination, so two more bytes would have been read via PIO overwriting the end of the buffer with wrong data. Make DMA stop handling more readable while we are here. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> 
DMA read requests could miss proper termination, so two more bytes would
have been read via PIO overwriting the end of the buffer with wrong
data. Make DMA stop handling more readable while we are here.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c: Only include slave support if selected 2015-01-26T21:05:20+00:00 Jean Delvare jdelvare@suse.de 2015-01-26T19:59:31+00:00 d5fd120e7860c2b3d4c936a2ebadb6b244bec4c8 Make the slave support depend on CONFIG_I2C_SLAVE. Otherwise it gets included unconditionally, even when it is not needed. I2C bus drivers which implement slave support must select I2C_SLAVE. Signed-off-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> 
Make the slave support depend on CONFIG_I2C_SLAVE. Otherwise it gets
included unconditionally, even when it is not needed.

I2C bus drivers which implement slave support must select
I2C_SLAVE.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c: s3c2410: fix ABBA deadlock by keeping clock prepared 2015-01-24T04:43:45+00:00 Paul Osmialowski p.osmialowsk@samsung.com 2015-01-19T16:03:33+00:00 34e81ad5f0b60007c95995eb7803da7e00c6c611 This patch solves deadlock between clock prepare mutex and regmap mutex reported by Tomasz Figa in [1] by implementing solution from [2]: "always leave the clock of the i2c controller in a prepared state". [1] https://lkml.org/lkml/2014/7/2/171 [2] https://lkml.org/lkml/2014/7/2/207 On each i2c transfer handled by s3c24xx_i2c_xfer(), clk_prepare_enable() was called, which calls clk_prepare() then clk_enable(). clk_prepare() takes prepare_lock mutex before proceeding. Note that i2c transfer functions are invoked from many places in kernel, typically with some other additional lock held. It may happen that function on CPU1 (e.g. regmap_update_bits()) has taken a mutex (i.e. regmap lock mutex) then it attempts i2c communication in order to proceed (so it needs to obtain clock related prepare_lock mutex during transfer preparation stage due to clk_prepare() call). At the same time other task on CPU0 wants to operate on clock (e.g. to (un)prepare clock for some other reason) so it has taken prepare_lock mutex. CPU0: CPU1: clk_disable_unused() regulator_disable() clk_prepare_lock() map->lock(map->lock_arg) regmap_read() s3c24xx_i2c_xfer() map->lock(map->lock_arg) clk_prepare_lock() Implemented solution from [2] leaves i2c clock prepared. Preparation is done in s3c24xx_i2c_probe() function. Without this patch, it is immediately unprepared by clk_disable_unprepare() call. I've replaced this call with clk_disable() and I've added clk_unprepare() call in s3c24xx_i2c_remove(). The s3c24xx_i2c_xfer() function now uses clk_enable() instead of clk_prepare_enable() (and clk_disable() instead of clk_unprepare_disable()). Signed-off-by: Paul Osmialowski <p.osmialowsk@samsung.com> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Cc: stable@kernel.org 
This patch solves deadlock between clock prepare mutex and regmap mutex reported
by Tomasz Figa in [1] by implementing solution from [2]: "always leave the clock
of the i2c controller in a prepared state".

[1] https://lkml.org/lkml/2014/7/2/171
[2] https://lkml.org/lkml/2014/7/2/207

On each i2c transfer handled by s3c24xx_i2c_xfer(), clk_prepare_enable() was
called, which calls clk_prepare() then clk_enable(). clk_prepare() takes
prepare_lock mutex before proceeding. Note that i2c transfer functions are
invoked from many places in kernel, typically with some other additional lock
held.

It may happen that function on CPU1 (e.g. regmap_update_bits()) has taken a
mutex (i.e. regmap lock mutex) then it attempts i2c communication in order to
proceed (so it needs to obtain clock related prepare_lock mutex during transfer
preparation stage due to clk_prepare() call). At the same time other task on
CPU0 wants to operate on clock (e.g. to (un)prepare clock for some other reason)
so it has taken prepare_lock mutex.

CPU0:                        CPU1:
clk_disable_unused()         regulator_disable()
  clk_prepare_lock()           map->lock(map->lock_arg)
  regmap_read()                s3c24xx_i2c_xfer()
    map->lock(map->lock_arg)     clk_prepare_lock()

Implemented solution from [2] leaves i2c clock prepared. Preparation is done in
s3c24xx_i2c_probe() function. Without this patch, it is immediately unprepared
by clk_disable_unprepare() call. I've replaced this call with clk_disable() and
I've added clk_unprepare() call in s3c24xx_i2c_remove().

The s3c24xx_i2c_xfer() function now uses clk_enable() instead of
clk_prepare_enable() (and clk_disable() instead of clk_unprepare_disable()).

Signed-off-by: Paul Osmialowski <p.osmialowsk@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
i2c: slave-eeprom: fix boundary check when using sysfs 2015-01-24T04:43:44+00:00 Wolfram Sang wsa+renesas@sang-engineering.com 2015-01-19T16:22:55+00:00 2541f7f4c14e2198ed8d8c61c854b86cae238cf1 Due to a copy&paste error, the last byte of the shared memory was not accessible via sysfs. Reported-by: Debora Grosse <debora@mds.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> 
Due to a copy&paste error, the last byte of the shared memory was not
accessible via sysfs.

Reported-by: Debora Grosse <debora@mds.com>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2014-12-20T21:52:52+00:00 Linus Torvalds torvalds@linux-foundation.org 2014-12-20T21:52:52+00:00 a4e1328a9d20ccf4a9e5a19fce172e6deb2a33e2 Pull more i2c updates from Wolfram Sang: "Included are two bugfixes needing some bigger refactoring (sh_mobile: deferred probe with DMA, mv64xxx: fix offload support) and one deprecated driver removal I thought would go in via ppc but I misunderstood. It has a proper ack from BenH" * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: sh_mobile: fix uninitialized var when debug is enabled macintosh: therm_pm72: delete deprecated driver i2c: sh_mobile: I2C_SH_MOBILE should depend on HAS_DMA i2c: sh_mobile: rework deferred probing i2c: sh_mobile: refactor DMA setup i2c: mv64xxx: rework offload support to fix several problems i2c: mv64xxx: use BIT() macro for register value definitions 
Pull more i2c updates from Wolfram Sang:
 "Included are two bugfixes needing some bigger refactoring (sh_mobile:
  deferred probe with DMA, mv64xxx: fix offload support) and one
  deprecated driver removal I thought would go in via ppc but I
  misunderstood.  It has a proper ack from BenH"

* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: sh_mobile: fix uninitialized var when debug is enabled
  macintosh: therm_pm72: delete deprecated driver
  i2c: sh_mobile: I2C_SH_MOBILE should depend on HAS_DMA
  i2c: sh_mobile: rework deferred probing
  i2c: sh_mobile: refactor DMA setup
  i2c: mv64xxx: rework offload support to fix several problems
  i2c: mv64xxx: use BIT() macro for register value definitions
i2c: sh_mobile: fix uninitialized var when debug is enabled 2014-12-20T08:28:09+00:00 Wolfram Sang wsa+renesas@sang-engineering.com 2014-12-16T12:31:26+00:00 fe07adec730d271c91f4160f96a0f24fe7553c63 Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> 
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>