diff options
| author | Hans de Goede <hdegoede@redhat.com> | 2017-02-10 11:27:57 +0100 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-03-02 15:46:34 +0100 |
| commit | 519e23a7f51e853dbe5dc4abb193c0c0db303b3a (patch) | |
| tree | 3e2a2bef7630cfc4fcee7e4d5dc42040b5bfdd5c /drivers/i2c | |
| parent | 086cb4afef45262806ee5bf26c34244e5867712c (diff) | |
| download | linux-519e23a7f51e853dbe5dc4abb193c0c0db303b3a.tar.bz2 | |
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
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-baytrail.c | 11 |
1 files changed, 2 insertions, 9 deletions
diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c b/drivers/i2c/busses/i2c-designware-baytrail.c index 650a700f215e..8df529c04f8e 100644 --- a/drivers/i2c/busses/i2c-designware-baytrail.c +++ b/drivers/i2c/busses/i2c-designware-baytrail.c @@ -47,15 +47,8 @@ static int get_sem(struct dw_i2c_dev *dev, u32 *sem) static void reset_semaphore(struct dw_i2c_dev *dev) { - u32 data; - - if (iosf_mbi_read(BT_MBI_UNIT_PMC, MBI_REG_READ, PUNIT_SEMAPHORE, &data)) { - dev_err(dev->dev, "iosf failed to reset punit semaphore during read\n"); - return; - } - - data &= ~PUNIT_SEMAPHORE_BIT; - if (iosf_mbi_write(BT_MBI_UNIT_PMC, MBI_REG_WRITE, PUNIT_SEMAPHORE, data)) + if (iosf_mbi_modify(BT_MBI_UNIT_PMC, MBI_REG_READ, PUNIT_SEMAPHORE, + 0, PUNIT_SEMAPHORE_BIT)) dev_err(dev->dev, "iosf failed to reset punit semaphore during write\n"); pm_qos_update_request(&dev->pm_qos, PM_QOS_DEFAULT_VALUE); |