diff options
| author |   Hans de Goede <hdegoede@redhat.com> | 2017-02-10 11:27:56 +0100 |
|---|---|---|
| committer |   Daniel Vetter <daniel.vetter@ffwll.ch> | 2017-03-02 15:46:33 +0100 |
| commit | 086cb4afef45262806ee5bf26c34244e5867712c (patch) | |
| tree | cf0a18a2be7cce0af7fe6a3f52adaeb0a55ba28d /drivers/i2c/busses/i2c-designware-core.h | |
| parent | i2c: designware-baytrail: Only check iosf_mbi_available() for shared hosts (diff) | |
| download | linux-dev-086cb4afef45262806ee5bf26c34244e5867712c.tar.xz linux-dev-086cb4afef45262806ee5bf26c34244e5867712c.zip | |
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
Diffstat (limited to 'drivers/i2c/busses/i2c-designware-core.h')
| -rw-r--r-- | drivers/i2c/busses/i2c-designware-core.h | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index 2c50571fb9c1..94a5fd193b40 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -23,6 +23,7 @@ */ #include <linux/i2c.h> +#include <linux/pm_qos.h> #define DW_IC_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C | \ I2C_FUNC_SMBUS_BYTE | \ @@ -75,6 +76,7 @@ * @fp_lcnt: fast plus LCNT value * @hs_hcnt: high speed HCNT value * @hs_lcnt: high speed LCNT value + * @pm_qos: pm_qos_request used while holding a hardware lock on the bus * @acquire_lock: function to acquire a hardware lock on the bus * @release_lock: function to release a hardware lock on the bus * @pm_runtime_disabled: true if pm runtime is disabled @@ -122,6 +124,7 @@ struct dw_i2c_dev { u16 fp_lcnt; u16 hs_hcnt; u16 hs_lcnt; + struct pm_qos_request pm_qos; int (*acquire_lock)(struct dw_i2c_dev *dev); void (*release_lock)(struct dw_i2c_dev *dev); bool pm_runtime_disabled; @@ -139,7 +142,9 @@ extern u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev); extern int i2c_dw_probe(struct dw_i2c_dev *dev); #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL) -extern int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev); +extern int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev); +extern void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev); #else -static inline int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev) { return 0; } +static inline int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) { return 0; } +static inline void i2c_dw_remove_lock_support(struct dw_i2c_dev *dev) {} #endif |