On 02/28/2017 10:38 PM, Jacek Anaszewski wrote:
I think that it would be simpler if we could initially see
a complete sample dts implementation containing all required DT
nodes. The example could contain timer trigger as well as usb-port
trigger specific bindings.
Please take a look at attached patch. I used it on Tenda AC9 with:
usb_trigger: usb-trigger {
trigger-type = "usbport";
ports = <&ohci_port1>, <&ehci_port1>;
};
usb {
label = "bcm53xx:blue:usb";
gpios = <&chipcommon 1 GPIO_ACTIVE_HIGH>;
triggers = <&usb_trigger>;
};
I suppose that we should see DT nodes containing #list-cells
properties that define the quantity of phandle arguments.
It seems that this approach allows for defining a list of elements
with variable number of arguments, i.e. what you were initially
asking for.
Are you sure we need #list-cells? Can't we simply use
of_count_phandle_with_args(np, "triggers", NULL);
?
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@xxxxxxxxxx>
Date: Mon, 3 Oct 2016 16:49:05 +0200
Subject: [PATCH] usb: core: read USB ports from DT in the usbport LED trigger
driver
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Signed-off-by: Rafał Miłecki <rafal@xxxxxxxxxx>
---
.../devicetree/bindings/leds/triggers-usbport.txt | 19 ++++++++
drivers/leds/led-triggers.c | 3 +-
drivers/usb/core/ledtrig-usbport.c | 56 ++++++++++++++++++++++
3 files changed, 77 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/leds/triggers-usbport.txt
diff --git a/Documentation/devicetree/bindings/leds/triggers-usbport.txt b/Documentation/devicetree/bindings/leds/triggers-usbport.txt
new file mode 100644
index 000000000000..10e55122cded
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/triggers-usbport.txt
@@ -0,0 +1,19 @@
+USB port LED trigger properties.
+
+USB port trigger can be used for signalling to the user a presence of USB
+device(s) in given ports. It's possible to specify USB ports in DT by providing
+their references.
+
+Properties:
+- trigger-type : Must be "usbport".
+- ports : List of USB ports related to this LED. Some devices may have one USB
+ LED for all ports, other may have few of them (e.g. USB version
+ specific). It's used by usbport trigger for reading a list of ports
+ that should cause LED to turn on whenver device get connected.
+
+Examples:
+
+usbport-trigger {
+ trigger-type = "usbport";
+ ports = <&ohci_port1>, <&ehci_port1>;
+};
diff --git a/drivers/leds/led-triggers.c b/drivers/leds/led-triggers.c
index c53c20d676cd..1d8bda9755ca 100644
--- a/drivers/leds/led-triggers.c
+++ b/drivers/leds/led-triggers.c
@@ -181,7 +181,8 @@ static void led_trigger_of_read_trigger(struct led_classdev *led_cdev)
}
/* Check if trigger specified in DT is supported */
- if (strcmp(trigger_type, "timer"))
+ if (strcmp(trigger_type, "timer") &&
+ strcmp(trigger_type, "usbport"))
goto err_node_put;
led_cdev->default_trigger = trigger_type;
diff --git a/drivers/usb/core/ledtrig-usbport.c b/drivers/usb/core/ledtrig-usbport.c
index 1713248ab15a..599f7e6b0ba8 100644
--- a/drivers/usb/core/ledtrig-usbport.c
+++ b/drivers/usb/core/ledtrig-usbport.c
@@ -11,8 +11,10 @@
#include <linux/device.h>
#include <linux/leds.h>
#include <linux/module.h>
+#include <linux/of.h>
#include <linux/slab.h>
#include <linux/usb.h>
+#include <linux/usb/of.h>
struct usbport_trig_data {
struct led_classdev *led_cdev;
@@ -123,6 +125,58 @@ static const struct attribute_group ports_group = {
* Adding & removing ports
***************************************/
+/**
+ * usbport_trig_port_observed - Check if port should be observed
+ *
+ * Each LED may have list of related USB ports specified in a DT. This function
+ * reads them using ports property and sets a proper state.
+ */
+static bool usbport_trig_port_observed(struct usbport_trig_data *usbport_data,
+ struct usb_device *usb_dev, int port1)
+{
+ struct device_node *led_np = usbport_data->led_cdev->trigger_node;
+ struct device *dev = usbport_data->led_cdev->dev;
+ struct of_phandle_args args;
+ struct device_node *port_np;
+ int count, i;
+
+ if (!led_np)
+ return false;
+
+ /* Get node of port being added */
+ port_np = usb_of_get_child_node(usb_dev->dev.of_node, port1);
+ if (!port_np)
+ return false;
+
+ /* Amount of ports this LED references */
+ count = of_count_phandle_with_args(led_np, "ports", NULL);
+ if (count < 0) {
+ dev_warn(dev, "Failed to get USB ports for %s\n",
+ led_np->full_name);
+ return false;
+ }
+
+ /* Check if port is on this LED's list */
+ for (i = 0; i < count; i++) {
+ int err;
+
+ err = of_parse_phandle_with_args(led_np, "ports", NULL, i,
+ &args);
+ if (err) {
+ dev_err(dev, "Failed to get USB port phandle at index %d: %d\n",
+ i, err);
+ continue;
+ }
+
+ of_node_put(args.np);
+
+ if (args.np == port_np)
+ return true;
+ }
+
+ return false;
+}
+
static int usbport_trig_add_port(struct usbport_trig_data *usbport_data,
struct usb_device *usb_dev,
const char *hub_name, int portnum)
@@ -141,6 +195,7 @@ static int usbport_trig_add_port(struct usbport_trig_data *usbport_data,
port->data = usbport_data;
port->hub = usb_dev;
port->portnum = portnum;
+ port->observed = usbport_trig_port_observed(usbport_data, usb_dev, portnum);
len = strlen(hub_name) + 8;
port->port_name = kzalloc(len, GFP_KERNEL);
@@ -255,6 +310,7 @@ static void usbport_trig_activate(struct led_classdev *led_cdev)
if (err)
goto err_free;
usb_for_each_dev(usbport_data, usbport_trig_add_usb_dev_ports);
+ usbport_trig_update_count(usbport_data);
/* Notifications */
usbport_data->nb.notifier_call = usbport_trig_notify,
--
2.11.0
