fpga: fpga-bridge: Add manual set option via sysfs

This patch is intented for manual testing only.
It is provide an option to manually test bridges.

Enabling bridge (!0 values are handled)
br1# echo 1 > set

Disable bridge
br1# echo 0 > set

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/Documentation/ABI/testing/sysfs-class-fpga-bridge b/Documentation/ABI/testing/sysfs-class-fpga-bridge
index 312ae2c579d8a4466d2b003858930c480875d83c..676700d7a61f11049c0ce271a38cd0772d0f258c 100644 (file)
--- a/Documentation/ABI/testing/sysfs-class-fpga-bridge
+++ b/Documentation/ABI/testing/sysfs-class-fpga-bridge
@@ -9,3 +9,12 @@ Date:          January 2016
 KernelVersion: 4.5
 Contact:       Alan Tull <atull@opensource.altera.com>
 Description:   Show bridge state as "enabled" or "disabled"
+
+What:          /sys/class/fpga_bridge/<bridge>/set
+Date:          January 2017
+KernelVersion: 4.9
+Contact:       Michal Simek <michal.simek@xilinx.com>
+Description:   Manual set bridge state (0-disable, !0 enable).
+               Enabling this option requires that the module is
+               compiled with #define DEBUG which is enabled by default
+               when CONFIG_DEBUG_KERNEL is setup.

diff --git a/drivers/fpga/fpga-bridge.c b/drivers/fpga/fpga-bridge.c
index 9651aa56244a562e0daadb8fd2de230ac7d99e9a..bd1f0e54a4eb08202ad3b2b0ef36f3721d01d0a2 100644 (file)
--- a/drivers/fpga/fpga-bridge.c
+++ b/drivers/fpga/fpga-bridge.c
@@ -23,6 +23,12 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 
+/* For enabling manual bridge set(enable/disable) function */
+#ifdef CONFIG_DEBUG_KERNEL
+#undef DEBUG
+#define DEBUG
+#endif
+
 static DEFINE_IDA(fpga_bridge_ida);
 static struct class *fpga_bridge_class;
 
@@ -258,9 +264,33 @@ static ssize_t state_show(struct device *dev,
 static DEVICE_ATTR_RO(name);
 static DEVICE_ATTR_RO(state);
 
+#ifdef DEBUG
+static ssize_t set_store(struct device *dev,
+                       struct device_attribute *attr,
+                       const char *buf, size_t count)
+{
+       struct fpga_bridge *bridge = to_fpga_bridge(dev);
+       long enable;
+       int ret;
+
+       ret = kstrtol(buf, 16, &enable);
+       if (ret)
+               return ret;
+
+       if (bridge->br_ops && bridge->br_ops->enable_set)
+               enable = bridge->br_ops->enable_set(bridge, !!enable);
+
+       return count;
+}
+static DEVICE_ATTR_WO(set);
+#endif
+
 static struct attribute *fpga_bridge_attrs[] = {
        &dev_attr_name.attr,
        &dev_attr_state.attr,
+#ifdef DEBUG
+       &dev_attr_set.attr,
+#endif
        NULL,
 };
 ATTRIBUTE_GROUPS(fpga_bridge);