dmaengine: idxd: export hw version through sysfs

Some user apps would like to know the hardware version in order to
determine the variation of the hardware. Export the hardware version number
to userspace via sysfs.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/158696714008.39484.13401950732606906479.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/Documentation/ABI/stable/sysfs-driver-dma-idxd b/Documentation/ABI/stable/sysfs-driver-dma-idxd
index f4be46cc6cb60e16570b7a3694743ddb9037e879..b5bebf642db697de112be8a4bd3d21b49ab9afb3 100644 (file)
--- a/Documentation/ABI/stable/sysfs-driver-dma-idxd
+++ b/Documentation/ABI/stable/sysfs-driver-dma-idxd
@@ -1,3 +1,9 @@
+What:          sys/bus/dsa/devices/dsa<m>/version
+Date:          Apr 15, 2020
+KernelVersion: 5.8.0
+Contact:       dmaengine@vger.kernel.org
+Description:   The hardware version number.
+
 What:           sys/bus/dsa/devices/dsa<m>/cdev_major
 Date:           Oct 25, 2019
 KernelVersion:         5.6.0

diff --git a/drivers/dma/idxd/sysfs.c b/drivers/dma/idxd/sysfs.c
index 3999827970abaedac05beacb4060431eec7d5840..052dae5d6dddbd6ff25d6a6b151b462b23aee91f 100644 (file)
--- a/drivers/dma/idxd/sysfs.c
+++ b/drivers/dma/idxd/sysfs.c
@@ -1092,6 +1092,16 @@ static const struct attribute_group *idxd_wq_attribute_groups[] = {
 };
 
 /* IDXD device attribs */
+static ssize_t version_show(struct device *dev, struct device_attribute *attr,
+                           char *buf)
+{
+       struct idxd_device *idxd =
+               container_of(dev, struct idxd_device, conf_dev);
+
+       return sprintf(buf, "%#x\n", idxd->hw.version);
+}
+static DEVICE_ATTR_RO(version);
+
 static ssize_t max_work_queues_size_show(struct device *dev,
                                         struct device_attribute *attr,
                                         char *buf)
@@ -1313,6 +1323,7 @@ static ssize_t cdev_major_show(struct device *dev,
 static DEVICE_ATTR_RO(cdev_major);
 
 static struct attribute *idxd_device_attributes[] = {
+       &dev_attr_version.attr,
        &dev_attr_max_groups.attr,
        &dev_attr_max_work_queues.attr,
        &dev_attr_max_work_queues_size.attr,