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authorLinus Torvalds <torvalds@linux-foundation.org>2022-06-03 11:36:34 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-06-03 11:36:34 -0700
commit6f9b5ed8caddfbc94af8307c557ed57a8ec5c65c (patch)
treedda90fb07a35fc07cf0cedc22f0f6be61b29cf53 /drivers/soundwire/cadence_master.c
parent54c2cc79194c961a213c1d375fe3aa4165664cc4 (diff)
parent90de6805267f8c79cd2b1a36805071e257c39b5c (diff)
Merge tag 'char-misc-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char / misc / other smaller driver subsystem updates from Greg KH: "Here is the large set of char, misc, and other driver subsystem updates for 5.19-rc1. The merge request for this has been delayed as I wanted to get lots of linux-next testing due to some late arrivals of changes for the habannalabs driver. Highlights of this merge are: - habanalabs driver updates for new hardware types and fixes and other updates - IIO driver tree merge which includes loads of new IIO drivers and cleanups and additions - PHY driver tree merge with new drivers and small updates to existing ones - interconnect driver tree merge with fixes and updates - soundwire driver tree merge with some small fixes - coresight driver tree merge with small fixes and updates - mhi bus driver tree merge with lots of updates and new device support - firmware driver updates - fpga driver updates - lkdtm driver updates (with a merge conflict, more on that below) - extcon driver tree merge with small updates - lots of other tiny driver updates and fixes and cleanups, full details in the shortlog. All of these have been in linux-next for almost 2 weeks with no reported problems" * tag 'char-misc-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (387 commits) habanalabs: use separate structure info for each error collect data habanalabs: fix missing handle shift during mmap habanalabs: remove hdev from hl_ctx_get args habanalabs: do MMU prefetch as deferred work habanalabs: order memory manager messages habanalabs: return -EFAULT on copy_to_user error habanalabs: use NULL for eventfd habanalabs: update firmware header habanalabs: add support for notification via eventfd habanalabs: add topic to memory manager buffer habanalabs: handle race in driver fini habanalabs: add device memory scrub ability through debugfs habanalabs: use unified memory manager for CB flow habanalabs: unified memory manager new code for CB flow habanalabs/gaudi: set arbitration timeout to a high value habanalabs: add put by handle method to memory manager habanalabs: hide memory manager page shift habanalabs: Add separate poll interval value for protocol habanalabs: use get_task_pid() to take PID habanalabs: add prefetch flag to the MAP operation ...
Diffstat (limited to 'drivers/soundwire/cadence_master.c')
-rw-r--r--drivers/soundwire/cadence_master.c42
1 files changed, 39 insertions, 3 deletions
diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index 558390af44b6..4fbb19557f5e 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -386,12 +386,11 @@ static int cdns_parity_error_injection(void *data, u64 value)
* Resume Master device. If this results in a bus reset, the
* Slave devices will re-attach and be re-enumerated.
*/
- ret = pm_runtime_get_sync(bus->dev);
+ ret = pm_runtime_resume_and_get(bus->dev);
if (ret < 0 && ret != -EACCES) {
dev_err_ratelimited(cdns->dev,
- "pm_runtime_get_sync failed in %s, ret %d\n",
+ "pm_runtime_resume_and_get failed in %s, ret %d\n",
__func__, ret);
- pm_runtime_put_noidle(bus->dev);
return ret;
}
@@ -959,6 +958,8 @@ static void cdns_update_slave_status_work(struct work_struct *work)
container_of(work, struct sdw_cdns, work);
u32 slave0, slave1;
u64 slave_intstat;
+ u32 device0_status;
+ int retry_count = 0;
slave0 = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT0);
slave1 = cdns_readl(cdns, CDNS_MCP_SLAVE_INTSTAT1);
@@ -968,10 +969,45 @@ static void cdns_update_slave_status_work(struct work_struct *work)
dev_dbg_ratelimited(cdns->dev, "Slave status change: 0x%llx\n", slave_intstat);
+update_status:
cdns_update_slave_status(cdns, slave_intstat);
cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT0, slave0);
cdns_writel(cdns, CDNS_MCP_SLAVE_INTSTAT1, slave1);
+ /*
+ * When there is more than one peripheral per link, it's
+ * possible that a deviceB becomes attached after we deal with
+ * the attachment of deviceA. Since the hardware does a
+ * logical AND, the attachment of the second device does not
+ * change the status seen by the driver.
+ *
+ * In that case, clearing the registers above would result in
+ * the deviceB never being detected - until a change of status
+ * is observed on the bus.
+ *
+ * To avoid this race condition, re-check if any device0 needs
+ * attention with PING commands. There is no need to check for
+ * ALERTS since they are not allowed until a non-zero
+ * device_number is assigned.
+ */
+
+ device0_status = cdns_readl(cdns, CDNS_MCP_SLAVE_STAT);
+ device0_status &= 3;
+
+ if (device0_status == SDW_SLAVE_ATTACHED) {
+ if (retry_count++ < SDW_MAX_DEVICES) {
+ dev_dbg_ratelimited(cdns->dev,
+ "Device0 detected after clearing status, iteration %d\n",
+ retry_count);
+ slave_intstat = CDNS_MCP_SLAVE_INTSTAT_ATTACHED;
+ goto update_status;
+ } else {
+ dev_err_ratelimited(cdns->dev,
+ "Device0 detected after %d iterations\n",
+ retry_count);
+ }
+ }
+
/* clear and unmask Slave interrupt now */
cdns_writel(cdns, CDNS_MCP_INTSTAT, CDNS_MCP_INT_SLAVE_MASK);
cdns_updatel(cdns, CDNS_MCP_INTMASK,