[char-misc-next 1/2] mei: show the HBM protocol versions in the device attributes

From: Tomas Winkler
Date: Sat Oct 29 2016 - 19:45:16 EST


From: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>

The HBM protocol version is negotiated during the setup phase, then settled
on a highest possible common version of the driver and the firmware.
The sysfs API advertises both negotiated and driver supported versions
in the device attributes.

Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
---
Documentation/ABI/testing/sysfs-class-mei | 16 ++++++++++++
drivers/misc/mei/main.c | 43 ++++++++++++++++++++++++++++++-
2 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-class-mei b/Documentation/ABI/testing/sysfs-class-mei
index 80d9888a8ece..5096a82f4cde 100644
--- a/Documentation/ABI/testing/sysfs-class-mei
+++ b/Documentation/ABI/testing/sysfs-class-mei
@@ -29,3 +29,19 @@ Description: Display fw status registers content
Also number of registers varies between 1 and 6
depending on generation.

+What: /sys/class/mei/meiN/hbm_ver
+Date: Aug 2016
+KernelVersion: 4.9
+Contact: Tomas Winkler <tomas.winkler@xxxxxxxxx>
+Description: Display the negotiated HBM protocol version.
+
+ The HBM protocol version negotiated
+ between the driver and the device.
+
+What: /sys/class/mei/meiN/hbm_ver_drv
+Date: Aug 2016
+KernelVersion: 4.9
+Contact: Tomas Winkler <tomas.winkler@xxxxxxxxx>
+Description: Display the driver HBM protocol version.
+
+ The HBM protocol version supported by the driver.
diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index fa50635512e8..a1484574cfa8 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -653,7 +653,7 @@ static int mei_fasync(int fd, struct file *file, int band)
}

/**
- * fw_status_show - mei device attribute show method
+ * fw_status_show - mei device fw_status attribute show method
*
* @device: device pointer
* @attr: attribute pointer
@@ -684,8 +684,49 @@ static ssize_t fw_status_show(struct device *device,
}
static DEVICE_ATTR_RO(fw_status);

+/**
+ * hbm_ver_show - display HBM protocol version negotiated with FW
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf: char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t hbm_ver_show(struct device *device,
+ struct device_attribute *attr, char *buf)
+{
+ struct mei_device *dev = dev_get_drvdata(device);
+ struct hbm_version ver;
+
+ mutex_lock(&dev->device_lock);
+ ver = dev->version;
+ mutex_unlock(&dev->device_lock);
+
+ return sprintf(buf, "%u.%u\n", ver.major_version, ver.minor_version);
+}
+static DEVICE_ATTR_RO(hbm_ver);
+
+/**
+ * hbm_ver_drv_show - display HBM protocol version advertised by driver
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf: char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t hbm_ver_drv_show(struct device *device,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "%u.%u\n", HBM_MAJOR_VERSION, HBM_MINOR_VERSION);
+}
+static DEVICE_ATTR_RO(hbm_ver_drv);
+
static struct attribute *mei_attrs[] = {
&dev_attr_fw_status.attr,
+ &dev_attr_hbm_ver.attr,
+ &dev_attr_hbm_ver_drv.attr,
NULL
};
ATTRIBUTE_GROUPS(mei);
--
2.7.4