Commit graph

18 commits

Author SHA1 Message Date
Colin Ian King c7f82ea860 i2c: designware-baytrail: fix potential null pointer dereference on dev
The assignment to addr requires a call to get_sem_addr that dereferences
dev, however, this dereference occurs before a null pointer check on dev.
Move this assignment after the null check on dev to avoid a potential null
pointer dereference.

Detected by CoverityScan, CID#1419700 ("Dereference before null check")

Fixes: fd476fa22a ("i2c: designware-baytrail: Add support for cherrytrail")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-04-19 21:00:13 +02:00
Hans de Goede 41c80b8a63 i2c: designware: Never suspend i2c-busses used for accessing the system PMIC
Currently we are already setting a pm_runtime_disabled flag and disabling
runtime-pm for i2c-busses used for accessing the system PMIC on x86.
But this is not enough, there are ACPI opregions which may want to access
the PMIC during late-suspend and early-resume, so we need to completely
disable pm to be safe.

This commit renames the flag from pm_runtime_disabled to pm_disabled and
adds the following new behavior if the flag is set:

1) Call dev_pm_syscore_device(dev, true) which disables normal suspend /
   resume and remove the pm_runtime_disabled check from dw_i2c_plat_resume
   since that will now never get called. This fixes suspend_late handlers
   which use ACPI PMIC opregions causing errors like these:

  PM: Suspending system (freeze)
  PM: suspend of devices complete after 1127.751 msecs
  i2c_designware 808622C1:06: timeout waiting for bus ready
  ACPI Exception: AE_ERROR, Returned by Handler for [UserDefinedRegion]
  acpi 80860F14:02: Failed to change power state to D3hot
  PM: late suspend of devices failed

2) Set IRQF_NO_SUSPEND irq flag. This fixes resume_early handlers which
   handlers which use ACPI PMIC opregions causing errors like these:

  PM: resume from suspend-to-idle
  i2c_designware 808622C1:06: controller timed out
  ACPI Exception: AE_ERROR, Returned by Handler for [UserDefinedRegion]

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-03-22 09:53:24 +01:00
Oliver Neukum 78c43af2c1 i2c-designware: increase timeout of semaphore transfer
Our testing shows the semaphore failing to be transferred on CherryTrail
in about 0.5% of all cases. The existing timeout needs to be lengthened
to accommodate the worst cases.

V2: Rebased on https://cgit.freedesktop.org/drm-intel/commit/?h=topic/designware-baytrail

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-03-22 09:45:00 +01:00
Hans de Goede d93a6ed370 i2c: designware-baytrail: Call pmic_bus_access_notifier_chain
Call the iosf_mbi pmic_bus_access_notifier_chain on bus acquire / release.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=155241
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: tagorereddy <tagore.chandan@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170210102802.20898-11-hdegoede@redhat.com
2017-03-02 15:46:36 +01:00
Hans de Goede 5b2cacceb7 i2c: designware-baytrail: Acquire P-Unit access on bus acquire
Acquire P-Unit access to stop others from accessing the P-Unit while the
PMIC i2c bus is in use. This is necessary because accessing the P-Unit
from the kernel may result in the P-Unit trying to access the PMIC i2c
bus, which results in a hang when it happens while we own the PMIC i2c
bus semaphore.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=155241
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: tagorereddy <tagore.chandan@gmail.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170210102802.20898-10-hdegoede@redhat.com
2017-03-02 15:46:35 +01:00
Hans de Goede fd476fa22a i2c: designware-baytrail: Add support for cherrytrail
The cherrytrail punit has the pmic i2c bus access semaphore at a
different register address.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170210102802.20898-9-hdegoede@redhat.com
2017-03-02 15:46:34 +01:00
Hans de Goede 519e23a7f5 i2c: designware-baytrail: Fix race when resetting the semaphore
Use iosf_mbi_modify instead of iosf_mbi_read + iosf_mbi_write so that
we keep the iosf_mbi_lock locked during the read-modify-write done to
reset the semaphore.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170210102802.20898-8-hdegoede@redhat.com
2017-03-02 15:46:34 +01:00
Hans de Goede 086cb4afef i2c: designware-baytrail: Disallow the CPU to enter C6 or C7 while holding the punit semaphore
On my cherrytrail tablet with axp288 pmic, just doing a bunch of repeated
reads from the pmic, e.g. "i2cdump -y 14 0x34" would lookup the tablet in
1 - 3 runs guaranteed.

This seems to be causes by the cpu trying to enter C6 or C7 while we hold
the punit bus semaphore, at which point everything just hangs.

Avoid this by disallowing the CPU to enter C6 or C7 before acquiring the
punit bus semaphore.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=109051
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170210102802.20898-7-hdegoede@redhat.com
2017-03-02 15:46:33 +01:00
Hans de Goede e234ed2f06 i2c: designware-baytrail: Only check iosf_mbi_available() for shared hosts
If (!shared_host) simply return 0, this avoids delaying the probe if
iosf_mbi_available() returns false when an i2c bus is not using the
punit semaphore.

Also move the if (!iosf_mbi_available()) check to above the
dev_info, so that we do not repeat the dev_info on every probe
until iosf_mbi_available() returns true.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170210102802.20898-6-hdegoede@redhat.com
2017-03-02 15:46:32 +01:00
Hans de Goede 62aee93753 i2c: designware-baytrail: Pass dw_i2c_dev into helper functions
Pass dw_i2c_dev into the helper functions, this is a preparation patch
for the punit semaphore fixes done in the other patches in this set.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170210102802.20898-5-hdegoede@redhat.com
2017-03-02 15:46:32 +01:00
Jean Delvare 942ab128ea i2c: designware-platform: Drop duplicate module information
The i2c-designware-platform module has duplicate module information
when CONFIG_I2C_DESIGNWARE_BAYTRAIL is set. It gets the information
from both i2c-designware-platdrv and i2c-designware-baytrail. The
latter is optional extra code which ends up in the same module so it
should not export module information.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2016-02-12 20:40:13 +01:00
Andy Shevchenko 4077a387b7 x86/platform/iosf_mbi: Remove duplicate definitions
The read and write opcodes are global for all units on SoC and even across
Intel SoCs. Remove duplication of corresponding constants. At the same time
convert all current users.

No functional change.

Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Boon Leong Ong <boon.leong.ong@intel.com>
Acked-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-12-09 01:18:34 +01:00
Andy Shevchenko ebf2ef8f61 i2c: designware-baytrail: baytrail_i2c_acquire() might sleep
This patch marks baytrail_i2c_acquire() that it might sleep. Also it chages
while-loop to do-while and, though it is matter of taste, gives a chance to
check one more time before report a timeout.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07 01:08:26 +01:00
Andy Shevchenko 30be774b38 i2c: designware-baytrail: cross-check lock functions
It seems the idea behind the cross-check is to prevent acquire semaphore when
there is no release callback and vice versa. Thus, patch fixes a typo.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07 01:08:06 +01:00
Andy Shevchenko c8e043e6f7 i2c: designware-baytrail: fix sparse warnings
There is no need to export functions that are used as the callbacks in the
struct dw_i2c_dev. Otherwise we get the following warnings:

drivers/i2c/busses/i2c-designware-baytrail.c:63:5: warning: symbol 'baytrail_i2c_acquire' was not declared. Should it be static?
drivers/i2c/busses/i2c-designware-baytrail.c:114:6: warning: symbol 'baytrail_i2c_release' was not declared. Should it be static?

While here, do few indentation fixes, remove i2c_dw_eval_lock_support() from
functions exported to the modules and redundant assignment of local sem
variable.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07 01:07:46 +01:00
Andy Shevchenko 259aada436 i2c: designware-baytrail: fix typo in error path
It seems we have same message for different return values in get_sem() and
baytrail_i2c_acquire(). I suspect this is just a typo, so this patch fixes it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07 01:07:27 +01:00
Andy Shevchenko 9b5c9f043e i2c: designware-baytrail: describe magic numbers
The patch converts hardcoded numerical constants to a named ones.

While here, align the variable name in get_sem() and reset_semaphore().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-03-07 01:07:07 +01:00
David Box 894acb2f82 i2c: designware: Add Intel Baytrail PMIC I2C bus support
This patch implements an I2C bus sharing mechanism between the host and platform
hardware on select Intel BayTrail SoC platforms using the X-Powers AXP288 PMIC.

On these platforms access to the PMIC must be shared with platform hardware. The
hardware unit assumes full control of the I2C bus and the host must request
access through a special semaphore. Hardware control of the bus also makes it
necessary to disable runtime pm to avoid interfering with hardware transactions.

Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2015-01-26 12:26:25 +01:00