diff options
| author | Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> | 2019-10-23 02:54:45 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2019-10-24 14:52:01 +0300 |
| commit | 675d4c9aba86cf3345bc61880e2edfd6762ef4ae (patch) | |
| tree | 7e970610c564a347ccc04694c73ba841fb4ab9d0 /drivers/soundwire | |
| parent | 49ea07d33d9a32c17e18b322e789507280ceb2a3 (diff) | |
| download | linux-675d4c9aba86cf3345bc61880e2edfd6762ef4ae.tar.xz | |
soundwire: cadence_master: add hw_reset capability in debugfs
Provide debugfs capability to kick link and devices into hard-reset
(as defined by MIPI). This capability is really useful when some
devices are no longer responsive and/or to check the software handling
of resynchronization.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191022235448.17586-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/soundwire')
| -rw-r--r-- | drivers/soundwire/cadence_master.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index 5337ccacccd1..7476e867468d 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -333,6 +333,26 @@ static int cdns_reg_show(struct seq_file *s, void *data) } DEFINE_SHOW_ATTRIBUTE(cdns_reg); +static int cdns_hw_reset(void *data, u64 value) +{ + struct sdw_cdns *cdns = data; + int ret; + + if (value != 1) + return -EINVAL; + + /* Userspace changed the hardware state behind the kernel's back */ + add_taint(TAINT_USER, LOCKDEP_STILL_OK); + + ret = sdw_cdns_exit_reset(cdns); + + dev_dbg(cdns->dev, "link hw_reset done: %d\n", ret); + + return ret; +} + +DEFINE_DEBUGFS_ATTRIBUTE(cdns_hw_reset_fops, NULL, cdns_hw_reset, "%llu\n"); + /** * sdw_cdns_debugfs_init() - Cadence debugfs init * @cdns: Cadence instance @@ -341,6 +361,9 @@ DEFINE_SHOW_ATTRIBUTE(cdns_reg); void sdw_cdns_debugfs_init(struct sdw_cdns *cdns, struct dentry *root) { debugfs_create_file("cdns-registers", 0400, root, cdns, &cdns_reg_fops); + + debugfs_create_file("cdns-hw-reset", 0200, root, cdns, + &cdns_hw_reset_fops); } EXPORT_SYMBOL_GPL(sdw_cdns_debugfs_init); |