Because the testunit can start tests in the future via the DELAY
register, it may happen that a command is still pending. Support
detecting that by returning the number of a command in progress (if
there is one).
Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/i2c/slave-testunit-backend.rst | 14 ++++++++------
drivers/i2c/i2c-slave-testunit.c | 4 ++--
2 files changed, 10 insertions(+), 8 deletions(-)
diff --git a/Documentation/i2c/slave-testunit-backend.rst b/Documentation/i2c/slave-testunit-backend.rst
index a0335782d109..b558adc59af2 100644
--- a/Documentation/i2c/slave-testunit-backend.rst
+++ b/Documentation/i2c/slave-testunit-backend.rst
@@ -20,11 +20,13 @@ Instantiating the device is regular. Example for bus 0, address 0x30::
# echo "slave-testunit 0x1030" > /sys/bus/i2c/devices/i2c-0/new_device
-After that, you will have a write-only device listening. Reads will just return
-an 8-bit version number of the testunit. When writing, the device consists of 4
-8-bit registers and, except for some "partial" commands, all registers must be
-written to start a testcase, i.e. you usually write 4 bytes to the device. The
-registers are:
+After that, you will have the device listening. Reading will return a single
+byte. Its value is 0 if the testunit is idle, otherwise the command number of
+the currently running command.
+
+When writing, the device consists of 4 8-bit registers and, except for some
+"partial" commands, all registers must be written to start a testcase, i.e. you
+usually write 4 bytes to the device. The registers are:
.. csv-table::
:header: "Offset", "Name", "Description"
@@ -170,4 +172,4 @@ are not equivalent to a REPEATED START. As an example, this returns just the
default response::
# i2cset -y 0 0x30 4 0 0 i; i2cget -y 0 0x30
- 0x01
+ 0x00
diff --git a/drivers/i2c/i2c-slave-testunit.c b/drivers/i2c/i2c-slave-testunit.c
index 19296ff09930..a3e1b5e8b659 100644
--- a/drivers/i2c/i2c-slave-testunit.c
+++ b/drivers/i2c/i2c-slave-testunit.c
@@ -15,7 +15,6 @@
#include <linux/slab.h>
#include <linux/workqueue.h> /* FIXME: is system_long_wq the best choice? */
-#define TU_CUR_VERSION 0x01
#define TU_VERSION_MAX_LENGTH 128
enum testunit_cmds {
@@ -159,7 +158,8 @@ static int i2c_slave_testunit_slave_cb(struct i2c_client *client,
else if (is_proc_call)
*val = tu->regs[TU_REG_DATAH];
else
- *val = TU_CUR_VERSION;
+ *val = test_bit(TU_FLAG_IN_PROCESS, &tu->flags) ?
+ tu->regs[TU_REG_CMD] : 0;
break;
}
--
2.43.0
