[PATCH v2 2/9] i2c: reject new transfers when adapters are suspended
From: Wolfram Sang <wsa+renesas@sang-engineering.com>
Date: 2018-12-22 20:26:40
Also in:
linux-i2c, linux-pm, linux-renesas-soc, lkml
Subsystem:
i2c subsystem, the rest · Maintainers:
Andi Shyti, Linus Torvalds
Using the 'is_suspended' flag from the PM core, we now reject new transfers if the parent of the adapter is already marked suspended. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> --- Documentation/i2c/fault-codes | 4 ++++ drivers/i2c/i2c-core-base.c | 3 +++ drivers/i2c/i2c-core-smbus.c | 4 ++++ 3 files changed, 11 insertions(+)
diff --git a/Documentation/i2c/fault-codes b/Documentation/i2c/fault-codes
index 47c25abb7d52..0cee0fc545b4 100644
--- a/Documentation/i2c/fault-codes
+++ b/Documentation/i2c/fault-codes@@ -112,6 +112,10 @@ EPROTO case is when the length of an SMBus block data response (from the SMBus slave) is outside the range 1-32 bytes. +ESHUTDOWN + Returned when a transfer was requested using an adapter + which is already suspended. + ETIMEDOUT This is returned by drivers when an operation took too much time, and was aborted before it completed.
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 28460f6a60cc..3ce238b782f3 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c@@ -1865,6 +1865,9 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) if (WARN_ON(!msgs || num < 1)) return -EINVAL; + if (WARN(device_is_suspended(adap->dev.parent), + "Accessing already suspended I2C/SMBus adapter")) + return -ESHUTDOWN; if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) return -EOPNOTSUPP;
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index 9cd66cabb84f..e0f7f22feabd 100644
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c@@ -547,6 +547,10 @@ s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, int try; s32 res; + if (WARN(device_is_suspended(adapter->dev.parent), + "Accessing already suspended I2C/SMBus adapter")) + return -ESHUTDOWN; + /* If enabled, the following two tracepoints are conditional on * read_write and protocol. */
--
2.19.1
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