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authorAlexander Shishkin2016-02-15 18:12:10 +0100
committerGreg Kroah-Hartman2016-02-20 23:09:14 +0100
commitadcde635f5d6b77e9f11087af09c6f62da2bf108 (patch)
tree8032cdef7bfbf3822db6a2979d3b59d40bcffeaa
parentstm class: Plug stm device's unlink callback (diff)
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stm class: dummy_stm: Add link callback for fault injection
STM device's link callback has the power to abort master/channel assignment by returning a negative error code. Use this in dummy stm device to optionally abort assigning certain channel IDs. This is useful as fault injection into the stm class core, for testing purposes. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/hwtracing/stm/dummy_stm.c14
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/hwtracing/stm/dummy_stm.c b/drivers/hwtracing/stm/dummy_stm.c
index 4ff5961cd36f..310adf57e7a1 100644
--- a/drivers/hwtracing/stm/dummy_stm.c
+++ b/drivers/hwtracing/stm/dummy_stm.c
@@ -50,6 +50,19 @@ module_param(nr_dummies, int, 0600);
static unsigned int dummy_stm_nr;
+static unsigned int fail_mode;
+
+module_param(fail_mode, int, 0600);
+
+static int dummy_stm_link(struct stm_data *data, unsigned int master,
+ unsigned int channel)
+{
+ if (fail_mode && (channel & fail_mode))
+ return -EINVAL;
+
+ return 0;
+}
+
static int dummy_stm_init(void)
{
int i, ret = -ENOMEM, __nr_dummies = ACCESS_ONCE(nr_dummies);
@@ -66,6 +79,7 @@ static int dummy_stm_init(void)
dummy_stm[i].sw_end = 0xffff;
dummy_stm[i].sw_nchannels = 0xffff;
dummy_stm[i].packet = dummy_stm_packet;
+ dummy_stm[i].link = dummy_stm_link;
ret = stm_register_device(NULL, &dummy_stm[i], THIS_MODULE);
if (ret)