[PATCH v2 0/6] power: add power sequence library

[PATCH v2 0/6] power: add power sequence library

[Peter Chen]

Hi all,

This is a follow-up for my last power sequence framework patch set [1].
According to Rob Herring and Ulf Hansson's comments[2], I use a generic
power sequence library for parsing the power sequence elements on DT,
and implement generic power sequence on library. The host driver
can allocate power sequence instance, and calls pwrseq APIs accordingly.

In future, if there are special power sequence requirements, the special
power sequence library can be created.

This patch set is tested on i.mx6 sabresx evk using a dts change, I use
two hot-plug devices to simulate this use case, the related binding
change is updated at patch[1/6], The udoo board changes were tested
using my last power sequence patch set.[3]

Except for hard-wired MMC and USB devices, I find the USB ULPI PHY also
need to power on itself before it can be found by ULPI bus.

[1] http://www.spinics.net/lists/linux-usb/msg142755.html
[2] http://www.spinics.net/lists/linux-usb/msg143106.html
[3] http://www.spinics.net/lists/linux-usb/msg142815.html

Changes for v2:
- Delete "pwrseq" prefix and clock-names for properties at dt binding
- Should use structure not but its pointer for kzalloc
- Since chipidea core has no of_node, let core's of_node equals glue
  layer's at core's probe


Peter Chen (6):
  binding-doc: power: pwrseq-generic: add binding doc for generic power
    sequence library
  power: add power sequence library
  binding-doc: usb: usb-device: add optional properties for power
    sequence
  usb: core: add power sequence handling for USB devices
  usb: chipidea: let chipidea core device of_node equal's glue layer
    device of_node
  ARM: dts: imx6qdl-udoo.dtsi: fix onboard USB HUB property

 .../bindings/power/pwrseq/pwrseq-generic.txt       |  53 ++++++++
 .../devicetree/bindings/usb/usb-device.txt         |   9 ++
 arch/arm/boot/dts/imx6qdl-udoo.dtsi                |  27 +++--
 drivers/power/Kconfig                              |   1 +
 drivers/power/Makefile                             |   1 +
 drivers/power/pwrseq/Kconfig                       |  20 +++
 drivers/power/pwrseq/Makefile                      |   2 +
 drivers/power/pwrseq/core.c                        |  79 ++++++++++++
 drivers/power/pwrseq/pwrseq_generic.c              | 134 +++++++++++++++++++++
 drivers/usb/chipidea/core.c                        |  10 ++
 drivers/usb/core/Makefile                          |   1 +
 drivers/usb/core/hub.c                             |  12 +-
 drivers/usb/core/hub.h                             |  12 ++
 drivers/usb/core/pwrseq.c                          | 102 ++++++++++++++++
 include/linux/power/pwrseq.h                       |  55 +++++++++
 15 files changed, 502 insertions(+), 16 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
 create mode 100644 drivers/power/pwrseq/Kconfig
 create mode 100644 drivers/power/pwrseq/Makefile
 create mode 100644 drivers/power/pwrseq/core.c
 create mode 100644 drivers/power/pwrseq/pwrseq_generic.c
 create mode 100644 drivers/usb/core/pwrseq.c
 create mode 100644 include/linux/power/pwrseq.h

-- 
1.9.1

[PATCH v2 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library

[Peter Chen]

Add binding doc for generic power sequence library.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 .../bindings/power/pwrseq/pwrseq-generic.txt       | 53 ++++++++++++++++++++++
 1 file changed, 53 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt

diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
new file mode 100644
index 0000000..186c58c
--- /dev/null
+++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
@@ -0,0 +1,53 @@
+The generic power sequence library
+
+Some hard-wired USB/MMC devices need to do power sequence to let the
+device work normally, the typical power sequence like: enable USB
+PHY clock, toggle reset pin, etc. But current Linux USB driver
+lacks of such code to do it, it may cause some hard-wired USB devices
+works abnormal or can't be recognized by controller at all. The
+power sequence will be done before this device can be found at USB
+bus.
+
+The power sequence properties is under the device node.
+
+Required properties:
+- power-sequence: this device needs to do power sequence before enumeration
+
+Optional properties:
+- clocks: the input clock for device.
+- reset-gpios: Should specify the GPIO for reset.
+- reset-duration-us: the duration in microsecond for assert reset signal.
+
+Below is the example of USB power sequence properties on USB device
+nodes which have two level USB hubs.
+
+&usbotg1 {
+	vbus-supply = <&reg_usb_otg1_vbus>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_usb_otg1_id>;
+	status = "okay";
+
+	#address-cells = <1>;
+	#size-cells = <0>;
+	hub: genesys at 1 {
+		compatible = "usb5e3,608";
+		reg = <1>;
+
+		power-sequence;
+		clocks = <&clks IMX6SX_CLK_CKO>;
+		reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */
+		reset-duration-us = <10>;
+
+		#address-cells = <1>;
+		#size-cells = <0>;
+		ethernet: asix at 1 {
+			compatible = "usbb95,1708";
+			reg = <1>;
+
+			power-sequence;
+			clocks = <&clks IMX6SX_CLK_IPG>;
+			reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */
+			reset-duration-us = <15>;
+		};
+	};
+};
-- 
1.9.1

[PATCH v2 2/6] power: add power sequence library

[Peter Chen]

We have an well-known problem that the device needs to do some power
sequence before it can be recognized by related host, the typical
example like hard-wired mmc devices and usb devices.

This power sequence is hard to be described at device tree and handled by
related host driver, so we have created a common power sequence
library to cover this requirement. The core code has supplied
some common helpers for host driver, and individual power sequence
libraries handle kinds of power sequence for devices.

pwrseq_generic is intended for general purpose of power sequence, which
handles gpios and clocks currently, and can cover regulator and pinctrl
in future. The host driver calls pwrseq_alloc_generic to create
an generic pwrseq instance.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/power/Kconfig                 |   1 +
 drivers/power/Makefile                |   1 +
 drivers/power/pwrseq/Kconfig          |  20 +++++
 drivers/power/pwrseq/Makefile         |   2 +
 drivers/power/pwrseq/core.c           |  79 ++++++++++++++++++++
 drivers/power/pwrseq/pwrseq_generic.c | 134 ++++++++++++++++++++++++++++++++++
 include/linux/power/pwrseq.h          |  55 ++++++++++++++
 7 files changed, 292 insertions(+)
 create mode 100644 drivers/power/pwrseq/Kconfig
 create mode 100644 drivers/power/pwrseq/Makefile
 create mode 100644 drivers/power/pwrseq/core.c
 create mode 100644 drivers/power/pwrseq/pwrseq_generic.c
 create mode 100644 include/linux/power/pwrseq.h

diff --git a/drivers/power/Kconfig b/drivers/power/Kconfig
index acd4a15..f6aa4fd 100644
--- a/drivers/power/Kconfig
+++ b/drivers/power/Kconfig
@@ -515,3 +515,4 @@ endif # POWER_SUPPLY
 
 source "drivers/power/reset/Kconfig"
 source "drivers/power/avs/Kconfig"
+source "drivers/power/pwrseq/Kconfig"
diff --git a/drivers/power/Makefile b/drivers/power/Makefile
index e46b75d..4ed2e12 100644
--- a/drivers/power/Makefile
+++ b/drivers/power/Makefile
@@ -74,3 +74,4 @@ obj-$(CONFIG_CHARGER_TPS65217)	+= tps65217_charger.o
 obj-$(CONFIG_POWER_RESET)	+= reset/
 obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
 obj-$(CONFIG_AXP288_CHARGER)	+= axp288_charger.o
+obj-$(CONFIG_POWER_SEQUENCE)	+= pwrseq/
diff --git a/drivers/power/pwrseq/Kconfig b/drivers/power/pwrseq/Kconfig
new file mode 100644
index 0000000..188729e
--- /dev/null
+++ b/drivers/power/pwrseq/Kconfig
@@ -0,0 +1,20 @@
+#
+# Power Sequence library
+#
+
+config POWER_SEQUENCE
+	bool
+
+menu "Power Sequence Support"
+
+config PWRSEQ_GENERIC
+	bool "Generic power sequence control"
+	depends on OF
+	select POWER_SEQUENCE
+	help
+	  It is used for drivers which needs to do power sequence
+	  (eg, turn on clock, toggle reset gpio) before the related
+	  devices can be found by hardware. This generic one can be
+	  used for common power sequence control.
+
+endmenu
diff --git a/drivers/power/pwrseq/Makefile b/drivers/power/pwrseq/Makefile
new file mode 100644
index 0000000..ad82389
--- /dev/null
+++ b/drivers/power/pwrseq/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_POWER_SEQUENCE) += core.o
+obj-$(CONFIG_PWRSEQ_GENERIC) += pwrseq_generic.o
diff --git a/drivers/power/pwrseq/core.c b/drivers/power/pwrseq/core.c
new file mode 100644
index 0000000..e40315c
--- /dev/null
+++ b/drivers/power/pwrseq/core.c
@@ -0,0 +1,79 @@
+/*
+ * core.c	power sequence core file
+ *
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Author: Peter Chen <peter.chen@nxp.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/power/pwrseq.h>
+
+static DEFINE_MUTEX(pwrseq_list_mutex);
+static LIST_HEAD(pwrseq_list);
+
+int pwrseq_get(struct device_node *np, struct pwrseq *p)
+{
+	if (p && p->get)
+		return p->get(np, p);
+
+	return -ENOTSUPP;
+}
+
+int pwrseq_on(struct device_node *np, struct pwrseq *p)
+{
+	if (p && p->on)
+		return p->on(np, p);
+
+	return -ENOTSUPP;
+}
+
+void pwrseq_off(struct pwrseq *p)
+{
+	if (p && p->off)
+		p->off(p);
+}
+
+void pwrseq_put(struct pwrseq *p)
+{
+	if (p && p->put)
+		p->put(p);
+}
+
+void pwrseq_free(struct pwrseq *p)
+{
+	if (p && p->free)
+		p->free(p);
+}
+
+void pwrseq_register(struct pwrseq *pwrseq)
+{
+	mutex_lock(&pwrseq_list_mutex);
+	list_add(&pwrseq->node, &pwrseq_list);
+	mutex_unlock(&pwrseq_list_mutex);
+}
+
+void pwrseq_unregister(struct pwrseq *pwrseq)
+{
+	mutex_lock(&pwrseq_list_mutex);
+	list_del(&pwrseq->node);
+	mutex_unlock(&pwrseq_list_mutex);
+}
+
+bool is_pwrseq_supported(struct device_node *np)
+{
+	if (of_find_property(np, "power-sequence", NULL))
+		return true;
+
+	return false;
+}
diff --git a/drivers/power/pwrseq/pwrseq_generic.c b/drivers/power/pwrseq/pwrseq_generic.c
new file mode 100644
index 0000000..20398aa
--- /dev/null
+++ b/drivers/power/pwrseq/pwrseq_generic.c
@@ -0,0 +1,134 @@
+/*
+ * pwrseq_generic.c	Generic power sequence handling
+ *
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Author: Peter Chen <peter.chen@nxp.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/slab.h>
+
+#include <linux/power/pwrseq.h>
+
+struct pwrseq_generic {
+	struct pwrseq pwrseq;
+	struct gpio_desc *gpiod_reset;
+	struct clk *clk;
+};
+
+#define to_generic_pwrseq(p) container_of(p, struct pwrseq_generic, pwrseq)
+
+static void pwrseq_generic_free(struct pwrseq *pwrseq)
+{
+	struct pwrseq_generic *pwrseq_gen = to_generic_pwrseq(pwrseq);
+
+	pwrseq_unregister(pwrseq);
+	kfree(pwrseq_gen);
+}
+
+static void pwrseq_generic_put(struct pwrseq *pwrseq)
+{
+	struct pwrseq_generic *pwrseq_gen = to_generic_pwrseq(pwrseq);
+
+	if (pwrseq_gen->gpiod_reset)
+		gpiod_put(pwrseq_gen->gpiod_reset);
+
+	clk_put(pwrseq_gen->clk);
+}
+
+static void pwrseq_generic_off(struct pwrseq *pwrseq)
+{
+	struct pwrseq_generic *pwrseq_gen = to_generic_pwrseq(pwrseq);
+
+	clk_disable_unprepare(pwrseq_gen->clk);
+}
+
+static int pwrseq_generic_on(struct device_node *np, struct pwrseq *pwrseq)
+{
+	struct pwrseq_generic *pwrseq_gen = to_generic_pwrseq(pwrseq);
+	int ret = 0;
+	u32 duration_us = 50;
+	struct gpio_desc *gpiod_reset = pwrseq_gen->gpiod_reset;
+
+	if (pwrseq_gen->clk) {
+		ret = clk_prepare_enable(pwrseq_gen->clk);
+		if (ret) {
+			pr_err("Can't enable clock on %s: %d\n",
+				np->name, ret);
+			return ret;
+		}
+	}
+
+	if (gpiod_reset) {
+		of_property_read_u32(np, "reset-duration-us",
+				&duration_us);
+		gpiod_direction_output(gpiod_reset, 1);
+		gpiod_set_value(gpiod_reset, 1);
+		usleep_range(duration_us, duration_us + 10);
+		gpiod_set_value(gpiod_reset, 0);
+	}
+
+	return ret;
+}
+
+static int pwrseq_generic_get(struct device_node *np, struct pwrseq *pwrseq)
+{
+	struct pwrseq_generic *pwrseq_gen = to_generic_pwrseq(pwrseq);
+	int gpio;
+
+	pwrseq_gen->clk = of_clk_get_by_name(np, NULL);
+	if (IS_ERR(pwrseq_gen->clk)) {
+		pr_debug("Can't get clock on %s: %ld\n",
+			np->name, PTR_ERR(pwrseq_gen->clk));
+		pwrseq_gen->clk = NULL;
+	}
+
+	gpio = of_get_named_gpio_flags(np, "reset-gpios", 0, NULL);
+	if (IS_ERR_VALUE(gpio) && (gpio != -ENODEV)) {
+		pr_err("Failed to get reset gpio on %s, err = %d\n",
+				np->name, gpio);
+		clk_put(pwrseq_gen->clk);
+		return gpio;
+	}
+
+	if (gpio != -ENODEV)
+		pwrseq_gen->gpiod_reset = gpio_to_desc(gpio);
+
+	return 0;
+}
+
+struct pwrseq *pwrseq_alloc_generic(void)
+{
+	struct pwrseq_generic *pwrseq_gen;
+
+	pwrseq_gen = kzalloc(sizeof(*pwrseq_gen), GFP_KERNEL);
+	if (!pwrseq_gen)
+		return ERR_PTR(-ENOMEM);
+
+	pwrseq_gen->pwrseq.get = pwrseq_generic_get;
+	pwrseq_gen->pwrseq.on = pwrseq_generic_on;
+	pwrseq_gen->pwrseq.off = pwrseq_generic_off;
+	pwrseq_gen->pwrseq.put = pwrseq_generic_put;
+	pwrseq_gen->pwrseq.free = pwrseq_generic_free;
+
+	pwrseq_register(&pwrseq_gen->pwrseq);
+	return &pwrseq_gen->pwrseq;
+}
+EXPORT_SYMBOL_GPL(pwrseq_alloc_generic);
diff --git a/include/linux/power/pwrseq.h b/include/linux/power/pwrseq.h
new file mode 100644
index 0000000..600f70c
--- /dev/null
+++ b/include/linux/power/pwrseq.h
@@ -0,0 +1,55 @@
+#ifndef __LINUX_PWRSEQ_H
+#define __LINUX_PWRSEQ_H
+
+#include <linux/of.h>
+
+struct pwrseq {
+	char *name;
+	struct list_head node;
+	int (*get)(struct device_node *np, struct pwrseq *p);
+	int (*on)(struct device_node *np, struct pwrseq *p);
+	void (*off)(struct pwrseq *p);
+	void (*put)(struct pwrseq *p);
+	void (*free)(struct pwrseq *p);
+};
+
+#if IS_ENABLED(CONFIG_POWER_SEQUENCE)
+int pwrseq_get(struct device_node *np, struct pwrseq *p);
+int pwrseq_on(struct device_node *np, struct pwrseq *p);
+void pwrseq_off(struct pwrseq *p);
+void pwrseq_put(struct pwrseq *p);
+void pwrseq_free(struct pwrseq *p);
+void pwrseq_register(struct pwrseq *pwrseq);
+void pwrseq_unregister(struct pwrseq *pwrseq);
+bool is_pwrseq_supported(struct device_node *np);
+
+#else
+static inline int pwrseq_get(struct device_node *np, struct pwrseq *p)
+{
+	return 0;
+}
+static inline int pwrseq_on(struct device_node *np, struct pwrseq *p)
+{
+	return 0;
+}
+static inline void pwrseq_off(struct pwrseq *p) {}
+static inline void pwrseq_put(struct pwrseq *p) {}
+static inline void pwrseq_free(struct pwrseq *p) {}
+static inline void pwrseq_register(struct pwrseq *pwrseq) {}
+static inline void pwrseq_unregister(struct pwrseq *pwrseq) {}
+static inline bool is_pwrseq_supported(struct device_node *np)
+{
+	return false;
+}
+#endif /* CONFIG_POWER_SEQUENCE */
+
+#if IS_ENABLED(CONFIG_PWRSEQ_GENERIC)
+struct pwrseq *pwrseq_alloc_generic(void);
+#else
+static inline struct pwrseq *pwrseq_alloc_generic(void)
+{
+	return NULL;
+}
+#endif /* CONFIG_PWRSEQ_GENERIC */
+
+#endif  /* __LINUX_PWRSEQ_H */
-- 
1.9.1

[PATCH v2 3/6] binding-doc: usb: usb-device: add optional properties for power sequence

[Peter Chen]

Add optional properties for power sequence.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 Documentation/devicetree/bindings/usb/usb-device.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/usb/usb-device.txt b/Documentation/devicetree/bindings/usb/usb-device.txt
index 1c35e7b..0ccaadf 100644
--- a/Documentation/devicetree/bindings/usb/usb-device.txt
+++ b/Documentation/devicetree/bindings/usb/usb-device.txt
@@ -13,6 +13,10 @@ Required properties:
 - reg: the port number which this device is connecting to, the range
   is 1-31.
 
+Optional properties:
+power sequence properties, see
+Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt for detail
+
 Example:
 
 &usb1 {
@@ -24,5 +28,10 @@ Example:
 	hub: genesys at 1 {
 		compatible = "usb5e3,608";
 		reg = <1>;
+
+		power-sequence;
+		clocks = <&clks IMX6SX_CLK_CKO>;
+		reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */
+		reset-duration-us = <10>;
 	};
 }
-- 
1.9.1

[PATCH v2 4/6] usb: core: add power sequence handling for USB devices

[Peter Chen]

Some hard-wired USB devices need to do power sequence to let the
device work normally, the typical power sequence like: enable USB
PHY clock, toggle reset pin, etc. But current Linux USB driver
lacks of such code to do it, it may cause some hard-wired USB devices
works abnormal or can't be recognized by controller at all.

In this patch, it calls power sequence library APIs to finish
the power sequence events. At first, it calls pwrseq_alloc_generic
to create a generic power sequence instance, then it will do power
on sequence at hub's probe for all devices under this hub
(includes root hub) if this device is described at dts and there
is a property "power-sequence" for it.

At hub_disconnect, it will do power off sequence which is at powered
on list.

Signed-off-by: Peter Chen <peter.chen@nxp.com>
---
 drivers/usb/core/Makefile |   1 +
 drivers/usb/core/hub.c    |  12 ++++--
 drivers/usb/core/hub.h    |  12 ++++++
 drivers/usb/core/pwrseq.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 124 insertions(+), 3 deletions(-)
 create mode 100644 drivers/usb/core/pwrseq.c

diff --git a/drivers/usb/core/Makefile b/drivers/usb/core/Makefile
index 9780877..39f2149 100644
--- a/drivers/usb/core/Makefile
+++ b/drivers/usb/core/Makefile
@@ -9,5 +9,6 @@ usbcore-y += port.o of.o
 
 usbcore-$(CONFIG_PCI)		+= hcd-pci.o
 usbcore-$(CONFIG_ACPI)		+= usb-acpi.o
+usbcore-$(CONFIG_PWRSEQ_GENERIC) += pwrseq.o
 
 obj-$(CONFIG_USB)		+= usbcore.o
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index bee1351..a346a8b 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -1700,6 +1700,7 @@ static void hub_disconnect(struct usb_interface *intf)
 	hub->error = 0;
 	hub_quiesce(hub, HUB_DISCONNECT);
 
+	hub_pwrseq_off(hub);
 	mutex_lock(&usb_port_peer_mutex);
 
 	/* Avoid races with recursively_mark_NOTATTACHED() */
@@ -1733,6 +1734,7 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 	struct usb_endpoint_descriptor *endpoint;
 	struct usb_device *hdev;
 	struct usb_hub *hub;
+	int ret = -ENODEV;
 
 	desc = intf->cur_altsetting;
 	hdev = interface_to_usbdev(intf);
@@ -1839,6 +1841,7 @@ descriptor_error:
 	INIT_DELAYED_WORK(&hub->leds, led_work);
 	INIT_DELAYED_WORK(&hub->init_work, NULL);
 	INIT_WORK(&hub->events, hub_event);
+	INIT_LIST_HEAD(&hub->pwrseq_on_list);
 	usb_get_intf(intf);
 	usb_get_dev(hdev);
 
@@ -1852,11 +1855,14 @@ descriptor_error:
 	if (id->driver_info & HUB_QUIRK_CHECK_PORT_AUTOSUSPEND)
 		hub->quirk_check_port_auto_suspend = 1;
 
-	if (hub_configure(hub, endpoint) >= 0)
-		return 0;
+	if (hub_configure(hub, endpoint) >= 0) {
+		ret = hub_pwrseq_on(hub);
+		if (!ret)
+			return 0;
+	}
 
 	hub_disconnect(intf);
-	return -ENODEV;
+	return ret;
 }
 
 static int
diff --git a/drivers/usb/core/hub.h b/drivers/usb/core/hub.h
index 34c1a7e..9473f6f 100644
--- a/drivers/usb/core/hub.h
+++ b/drivers/usb/core/hub.h
@@ -78,6 +78,7 @@ struct usb_hub {
 	struct delayed_work	init_work;
 	struct work_struct      events;
 	struct usb_port		**ports;
+	struct list_head	pwrseq_on_list; /* powered pwrseq node list */
 };
 
 /**
@@ -166,3 +167,14 @@ static inline int hub_port_debounce_be_stable(struct usb_hub *hub,
 {
 	return hub_port_debounce(hub, port1, false);
 }
+
+#if IS_ENABLED(CONFIG_PWRSEQ_GENERIC)
+int hub_pwrseq_on(struct usb_hub *hub);
+void hub_pwrseq_off(struct usb_hub *hub);
+#else
+static inline int hub_pwrseq_on(struct usb_hub *hub)
+{
+	return 0;
+}
+static inline void hub_pwrseq_off(struct usb_hub *hub) {}
+#endif /* CONFIG_PWRSEQ_GENERIC */
diff --git a/drivers/usb/core/pwrseq.c b/drivers/usb/core/pwrseq.c
new file mode 100644
index 0000000..df171ed
--- /dev/null
+++ b/drivers/usb/core/pwrseq.c
@@ -0,0 +1,102 @@
+/*
+ * pwrseq.c	USB device power sequence management
+ *
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ * Author: Peter Chen <peter.chen@nxp.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/list.h>
+#include <linux/of.h>
+#include <linux/power/pwrseq.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+
+#include "hub.h"
+
+struct usb_pwrseq_node {
+	struct pwrseq *pwrseq;
+	struct list_head list;
+};
+
+static int hub_of_pwrseq_on(struct device_node *np, struct usb_hub *hub)
+{
+	struct pwrseq *pwrseq;
+	struct usb_pwrseq_node *pwrseq_node;
+	int ret;
+
+	pwrseq = pwrseq_alloc_generic();
+	if (IS_ERR(pwrseq))
+		return PTR_ERR(pwrseq);
+
+	ret = pwrseq_get(np, pwrseq);
+	if (ret)
+		goto pwr_free;
+
+	ret = pwrseq_on(np, pwrseq);
+	if (ret)
+		goto pwr_put;
+
+	pwrseq_node = kzalloc(sizeof(*pwrseq_node), GFP_KERNEL);
+	pwrseq_node->pwrseq = pwrseq;
+	list_add(&pwrseq_node->list, &hub->pwrseq_on_list);
+
+	return 0;
+
+pwr_put:
+	pwrseq_put(pwrseq);
+pwr_free:
+	pwrseq_free(pwrseq);
+	return ret;
+}
+
+int hub_pwrseq_on(struct usb_hub *hub)
+{
+	struct device *parent;
+	struct usb_device *hdev = hub->hdev;
+	struct device_node *np;
+	int ret;
+
+	if (hdev->parent)
+		parent = &hdev->dev;
+	else
+		parent = bus_to_hcd(hdev->bus)->self.controller;
+
+	for_each_child_of_node(parent->of_node, np) {
+		if (is_pwrseq_supported(np)) {
+			ret = hub_of_pwrseq_on(np, hub);
+			if (ret)
+				return ret;
+		}
+	}
+
+	return 0;
+}
+
+void hub_pwrseq_off(struct usb_hub *hub)
+{
+	struct pwrseq *pwrseq;
+	struct usb_pwrseq_node *pwrseq_node, *tmp_node;
+
+	list_for_each_entry_safe(pwrseq_node, tmp_node,
+			&hub->pwrseq_on_list, list) {
+		pwrseq = pwrseq_node->pwrseq;
+		pwrseq_off(pwrseq);
+		pwrseq_put(pwrseq);
+		pwrseq_free(pwrseq);
+		list_del(&pwrseq_node->list);
+		kfree(pwrseq_node);
+	}
+}
-- 
1.9.1

[PATCH v2 5/6] usb: chipidea: let chipidea core device of_node equal's glue layer device of_node

[Peter Chen]

From: Peter Chen <peter.chen@freescale.com>

At device tree, we have no device node for chipidea core,
the glue layer's node is the parent node for host and udc
device. But in related driver, the parent device is chipidea
core. So, in order to let the common driver get parent's node,
we let the core's device node equals glue layer device node.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Tested-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
---
 drivers/usb/chipidea/core.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/usb/chipidea/core.c b/drivers/usb/chipidea/core.c
index 69426e6..0d05812 100644
--- a/drivers/usb/chipidea/core.c
+++ b/drivers/usb/chipidea/core.c
@@ -914,6 +914,16 @@ static int ci_hdrc_probe(struct platform_device *pdev)
 	if (!ci)
 		return -ENOMEM;
 
+	/*
+	 * At device tree, we have no device node for chipidea core,
+	 * the glue layer's node is the parent node for host and udc
+	 * device. But in related driver, the parent device is chipidea
+	 * core. So, in order to let the common driver get parent's node,
+	 * we let the core's device node equals glue layer's node.
+	 */
+	if (dev->parent && dev->parent->of_node)
+		dev->of_node = dev->parent->of_node;
+
 	ci->dev = dev;
 	ci->platdata = dev_get_platdata(dev);
 	ci->imx28_write_fix = !!(ci->platdata->flags &
-- 
1.9.1

[PATCH v2 6/6] ARM: dts: imx6qdl-udoo.dtsi: fix onboard USB HUB property

[Peter Chen]

From: Peter Chen <peter.chen@freescale.com>

The current dts describes USB HUB's property at USB controller's
entry, it is improper. The USB HUB should be the child node
under USB controller, and power sequence properties are under
it.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
---
 arch/arm/boot/dts/imx6qdl-udoo.dtsi | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/arch/arm/boot/dts/imx6qdl-udoo.dtsi b/arch/arm/boot/dts/imx6qdl-udoo.dtsi
index 3bee2f9..492fc5d 100644
--- a/arch/arm/boot/dts/imx6qdl-udoo.dtsi
+++ b/arch/arm/boot/dts/imx6qdl-udoo.dtsi
@@ -9,6 +9,8 @@
  *
  */
 
+#include <dt-bindings/gpio/gpio.h>
+
 / {
 	aliases {
 		backlight = &backlight;
@@ -58,17 +60,6 @@
 		#address-cells = <1>;
 		#size-cells = <0>;
 
-		reg_usb_h1_vbus: regulator at 0 {
-			compatible = "regulator-fixed";
-			reg = <0>;
-			regulator-name = "usb_h1_vbus";
-			regulator-min-microvolt = <5000000>;
-			regulator-max-microvolt = <5000000>;
-			enable-active-high;
-			startup-delay-us = <2>; /* USB2415 requires a POR of 1 us minimum */
-			gpio = <&gpio7 12 0>;
-		};
-
 		reg_panel: regulator at 1 {
 			compatible = "regulator-fixed";
 			reg = <1>;
@@ -259,9 +250,19 @@
 &usbh1 {
 	pinctrl-names = "default";
 	pinctrl-0 = <&pinctrl_usbh>;
-	vbus-supply = <&reg_usb_h1_vbus>;
-	clocks = <&clks IMX6QDL_CLK_CKO>;
 	status = "okay";
+
+	#address-cells = <1>;
+	#size-cells = <0>;
+	hub: usb2415 at 1 {
+		compatible = "usb424,2514";
+		reg = <1>;
+
+		power-sequence;
+		clocks = <&clks IMX6QDL_CLK_CKO>;
+		reset-gpios = <&gpio7 12 GPIO_ACTIVE_LOW>;
+		reset-duration-us = <3000>;
+	};
 };
 
 &usdhc3 {
-- 
1.9.1

[PATCH v2 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library

[Philipp Zabel]

Am Mittwoch, den 13.07.2016, 10:06 +0800 schrieb Peter Chen:
> Add binding doc for generic power sequence library.
> 
> Signed-off-by: Peter Chen <peter.chen@nxp.com>
> ---
>  .../bindings/power/pwrseq/pwrseq-generic.txt       | 53 ++++++++++++++++++++++
>  1 file changed, 53 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> 
> diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> new file mode 100644
> index 0000000..186c58c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> @@ -0,0 +1,53 @@
> +The generic power sequence library
> +
> +Some hard-wired USB/MMC devices need to do power sequence to let the
> +device work normally,

I would replace "to let the device work normally" with "before the
device can be enumerated [on the bus]" here.

>  the typical power sequence like: enable USB
> +PHY clock, toggle reset pin, etc. But current Linux USB driver
> +lacks of such code to do it, it may cause some hard-wired USB devices
> +works abnormal or can't be recognized by controller at all. The
> +power sequence will be done before this device can be found at USB
> +bus.
> +
> +The power sequence properties is under the device node.
> +
> +Required properties:
> +- power-sequence: this device needs to do power sequence before enumeration

As Joshua pointed out, is this even needed at all?

> +Optional properties:
> +- clocks: the input clock for device.
> +- reset-gpios: Should specify the GPIO for reset.
> +- reset-duration-us: the duration in microsecond for assert reset signal.

With the above two issues sorted out,
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>

regards
Philipp

[PATCH v2 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library

[Peter Chen]

On Wed, Jul 13, 2016 at 09:27:31AM +0200, Philipp Zabel wrote:
> Am Mittwoch, den 13.07.2016, 10:06 +0800 schrieb Peter Chen:
> > Add binding doc for generic power sequence library.
> > 
> > Signed-off-by: Peter Chen <peter.chen@nxp.com>
> > ---
> >  .../bindings/power/pwrseq/pwrseq-generic.txt       | 53 ++++++++++++++++++++++
> >  1 file changed, 53 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> > new file mode 100644
> > index 0000000..186c58c
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> > @@ -0,0 +1,53 @@
> > +The generic power sequence library
> > +
> > +Some hard-wired USB/MMC devices need to do power sequence to let the
> > +device work normally,
> 
> I would replace "to let the device work normally" with "before the
> device can be enumerated [on the bus]" here.
> 

Ok.

> >  the typical power sequence like: enable USB
> > +PHY clock, toggle reset pin, etc. But current Linux USB driver
> > +lacks of such code to do it, it may cause some hard-wired USB devices
> > +works abnormal or can't be recognized by controller at all. The
> > +power sequence will be done before this device can be found at USB
> > +bus.
> > +
> > +The power sequence properties is under the device node.
> > +
> > +Required properties:
> > +- power-sequence: this device needs to do power sequence before enumeration
> 
> As Joshua pointed out, is this even needed at all?
> 

If no, how we decide whether allocates pwrseq instance through pwrseq
library or not?

-- 

Best Regards,
Peter Chen

[PATCH v2 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library

[Joshua Clayton]

On 07/13/2016 01:42 AM, Peter Chen wrote:
> On Wed, Jul 13, 2016 at 09:27:31AM +0200, Philipp Zabel wrote:
>> Am Mittwoch, den 13.07.2016, 10:06 +0800 schrieb Peter Chen:
>>> Add binding doc for generic power sequence library.
>>>
>>> Signed-off-by: Peter Chen <peter.chen@nxp.com>
>>> ---
>>>  .../bindings/power/pwrseq/pwrseq-generic.txt       | 53 ++++++++++++++++++++++
>>>  1 file changed, 53 insertions(+)
>>>  create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
>>> new file mode 100644
>>> index 0000000..186c58c
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
>>> @@ -0,0 +1,53 @@
>>> +The generic power sequence library
>>> +
>>> +Some hard-wired USB/MMC devices need to do power sequence to let the
>>> +device work normally,
>> I would replace "to let the device work normally" with "before the
>> device can be enumerated [on the bus]" here.
>>
> Ok.
>
>>>  the typical power sequence like: enable USB
>>> +PHY clock, toggle reset pin, etc. But current Linux USB driver
>>> +lacks of such code to do it, it may cause some hard-wired USB devices
>>> +works abnormal or can't be recognized by controller at all. The
>>> +power sequence will be done before this device can be found at USB
>>> +bus.
>>> +
>>> +The power sequence properties is under the device node.
>>> +
>>> +Required properties:
>>> +- power-sequence: this device needs to do power sequence before enumeration
>> As Joshua pointed out, is this even needed at all?
>>
> If no, how we decide whether allocates pwrseq instance through pwrseq
> library or not?
>
The pwrseq driver is Linux specific. The dts is supposed to be OS agnostic.
It seems to me that If a driver supports pwrseq and the dts elements
are there, it should use them, e.g. if there is a clock, enable the clock.
if there is a reset gpio then take the device into and out of reset during probe.

Can you see a  problem with that approach?

[PATCH v2 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library

[Peter Chen]

On Wed, Jul 13, 2016 at 04:20:06PM -0700, Joshua Clayton wrote:
> 
> 
> On 07/13/2016 01:42 AM, Peter Chen wrote:
> > On Wed, Jul 13, 2016 at 09:27:31AM +0200, Philipp Zabel wrote:
> >> Am Mittwoch, den 13.07.2016, 10:06 +0800 schrieb Peter Chen:
> >>> Add binding doc for generic power sequence library.
> >>>
> >>> Signed-off-by: Peter Chen <peter.chen@nxp.com>
> >>> ---
> >>>  .../bindings/power/pwrseq/pwrseq-generic.txt       | 53 ++++++++++++++++++++++
> >>>  1 file changed, 53 insertions(+)
> >>>  create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> >>>
> >>> diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> >>> new file mode 100644
> >>> index 0000000..186c58c
> >>> --- /dev/null
> >>> +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> >>> @@ -0,0 +1,53 @@
> >>> +The generic power sequence library
> >>> +
> >>> +Some hard-wired USB/MMC devices need to do power sequence to let the
> >>> +device work normally,
> >> I would replace "to let the device work normally" with "before the
> >> device can be enumerated [on the bus]" here.
> >>
> > Ok.
> >
> >>>  the typical power sequence like: enable USB
> >>> +PHY clock, toggle reset pin, etc. But current Linux USB driver
> >>> +lacks of such code to do it, it may cause some hard-wired USB devices
> >>> +works abnormal or can't be recognized by controller at all. The
> >>> +power sequence will be done before this device can be found at USB
> >>> +bus.
> >>> +
> >>> +The power sequence properties is under the device node.
> >>> +
> >>> +Required properties:
> >>> +- power-sequence: this device needs to do power sequence before enumeration
> >> As Joshua pointed out, is this even needed at all?
> >>
> > If no, how we decide whether allocates pwrseq instance through pwrseq
> > library or not?
> >
> The pwrseq driver is Linux specific. The dts is supposed to be OS agnostic.
> It seems to me that If a driver supports pwrseq and the dts elements
> are there, it should use them, e.g. if there is a clock, enable the clock.
> if there is a reset gpio then take the device into and out of reset during probe.
> 

I agree with you, will delete this property.

-- 

Best Regards,
Peter Chen

[PATCH v2 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library

[Rob Herring]

On Wed, Jul 13, 2016 at 10:06:45AM +0800, Peter Chen wrote:
> Add binding doc for generic power sequence library.

I'd written a review on last version, but forgot to send it out. Anyway, 
I mostly had the same comments as Philipp and Joshua. A couple of things 
they missed...

> 
> Signed-off-by: Peter Chen <peter.chen@nxp.com>
> ---
>  .../bindings/power/pwrseq/pwrseq-generic.txt       | 53 ++++++++++++++++++++++
>  1 file changed, 53 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> 
> diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> new file mode 100644
> index 0000000..186c58c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> @@ -0,0 +1,53 @@
> +The generic power sequence library
> +
> +Some hard-wired USB/MMC devices need to do power sequence to let the
> +device work normally, the typical power sequence like: enable USB
> +PHY clock, toggle reset pin, etc. But current Linux USB driver
> +lacks of such code to do it, it may cause some hard-wired USB devices
> +works abnormal or can't be recognized by controller at all. The
> +power sequence will be done before this device can be found at USB
> +bus.
> +
> +The power sequence properties is under the device node.
> +
> +Required properties:
> +- power-sequence: this device needs to do power sequence before enumeration
> +
> +Optional properties:
> +- clocks: the input clock for device.
> +- reset-gpios: Should specify the GPIO for reset.
> +- reset-duration-us: the duration in microsecond for assert reset signal.
> +
> +Below is the example of USB power sequence properties on USB device
> +nodes which have two level USB hubs.
> +
> +&usbotg1 {
> +	vbus-supply = <&reg_usb_otg1_vbus>;
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&pinctrl_usb_otg1_id>;
> +	status = "okay";
> +
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +	hub: genesys at 1 {

genesys: hub at 1

> +		compatible = "usb5e3,608";
> +		reg = <1>;
> +
> +		power-sequence;
> +		clocks = <&clks IMX6SX_CLK_CKO>;
> +		reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */
> +		reset-duration-us = <10>;
> +
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +		ethernet: asix at 1 {

asix: ethernet at 1

> +			compatible = "usbb95,1708";
> +			reg = <1>;
> +
> +			power-sequence;
> +			clocks = <&clks IMX6SX_CLK_IPG>;
> +			reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */
> +			reset-duration-us = <15>;
> +		};
> +	};
> +};
> -- 
> 1.9.1
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

[PATCH v2 3/6] binding-doc: usb: usb-device: add optional properties for power sequence

[Rob Herring]

On Wed, Jul 13, 2016 at 10:06:47AM +0800, Peter Chen wrote:
> Add optional properties for power sequence.
> 
> Signed-off-by: Peter Chen <peter.chen@nxp.com>
> ---
>  Documentation/devicetree/bindings/usb/usb-device.txt | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/usb/usb-device.txt b/Documentation/devicetree/bindings/usb/usb-device.txt
> index 1c35e7b..0ccaadf 100644
> --- a/Documentation/devicetree/bindings/usb/usb-device.txt
> +++ b/Documentation/devicetree/bindings/usb/usb-device.txt
> @@ -13,6 +13,10 @@ Required properties:
>  - reg: the port number which this device is connecting to, the range
>    is 1-31.
>  
> +Optional properties:
> +power sequence properties, see
> +Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt for detail
> +
>  Example:
>  
>  &usb1 {
> @@ -24,5 +28,10 @@ Example:
>  	hub: genesys at 1 {
>  		compatible = "usb5e3,608";
>  		reg = <1>;
> +
> +		power-sequence;
> +		clocks = <&clks IMX6SX_CLK_CKO>;
> +		reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */
> +		reset-duration-us = <10>;

These belong in the binding doc for the hub.

>  	};
>  }
> -- 
> 1.9.1
> 
> --
> To unsubscribe from this list: send the line "unsubscribe devicetree" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH v2 3/6] binding-doc: usb: usb-device: add optional properties for power sequence

[Peter Chen]

On Sat, Jul 16, 2016 at 05:31:59PM -0500, Rob Herring wrote:
> On Wed, Jul 13, 2016 at 10:06:47AM +0800, Peter Chen wrote:
> > Add optional properties for power sequence.
> > 
> > Signed-off-by: Peter Chen <peter.chen@nxp.com>
> > ---
> >  Documentation/devicetree/bindings/usb/usb-device.txt | 9 +++++++++
> >  1 file changed, 9 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/usb/usb-device.txt b/Documentation/devicetree/bindings/usb/usb-device.txt
> > index 1c35e7b..0ccaadf 100644
> > --- a/Documentation/devicetree/bindings/usb/usb-device.txt
> > +++ b/Documentation/devicetree/bindings/usb/usb-device.txt
> > @@ -13,6 +13,10 @@ Required properties:
> >  - reg: the port number which this device is connecting to, the range
> >    is 1-31.
> >  
> > +Optional properties:
> > +power sequence properties, see
> > +Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt for detail
> > +
> >  Example:
> >  
> >  &usb1 {
> > @@ -24,5 +28,10 @@ Example:
> >  	hub: genesys at 1 {
> >  		compatible = "usb5e3,608";
> >  		reg = <1>;
> > +
> > +		power-sequence;
> > +		clocks = <&clks IMX6SX_CLK_CKO>;
> > +		reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */
> > +		reset-duration-us = <10>;
> 
> These belong in the binding doc for the hub.
> 

There is no dedicated binding doc for USB hub, we only have this binding
doc for hard-wired USB devices.

-- 

Best Regards,
Peter Chen

[PATCH v2 1/6] binding-doc: power: pwrseq-generic: add binding doc for generic power sequence library

[Peter Chen]

On Sat, Jul 16, 2016 at 05:30:57PM -0500, Rob Herring wrote:
> On Wed, Jul 13, 2016 at 10:06:45AM +0800, Peter Chen wrote:
> > Add binding doc for generic power sequence library.
> 
> I'd written a review on last version, but forgot to send it out. Anyway, 
> I mostly had the same comments as Philipp and Joshua. A couple of things 
> they missed...
> 
> > 
> > Signed-off-by: Peter Chen <peter.chen@nxp.com>
> > ---
> >  .../bindings/power/pwrseq/pwrseq-generic.txt       | 53 ++++++++++++++++++++++
> >  1 file changed, 53 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> > 
> > diff --git a/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> > new file mode 100644
> > index 0000000..186c58c
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> > @@ -0,0 +1,53 @@
> > +The generic power sequence library
> > +
> > +Some hard-wired USB/MMC devices need to do power sequence to let the
> > +device work normally, the typical power sequence like: enable USB
> > +PHY clock, toggle reset pin, etc. But current Linux USB driver
> > +lacks of such code to do it, it may cause some hard-wired USB devices
> > +works abnormal or can't be recognized by controller at all. The
> > +power sequence will be done before this device can be found at USB
> > +bus.
> > +
> > +The power sequence properties is under the device node.
> > +
> > +Required properties:
> > +- power-sequence: this device needs to do power sequence before enumeration
> > +
> > +Optional properties:
> > +- clocks: the input clock for device.
> > +- reset-gpios: Should specify the GPIO for reset.
> > +- reset-duration-us: the duration in microsecond for assert reset signal.
> > +
> > +Below is the example of USB power sequence properties on USB device
> > +nodes which have two level USB hubs.
> > +
> > +&usbotg1 {
> > +	vbus-supply = <&reg_usb_otg1_vbus>;
> > +	pinctrl-names = "default";
> > +	pinctrl-0 = <&pinctrl_usb_otg1_id>;
> > +	status = "okay";
> > +
> > +	#address-cells = <1>;
> > +	#size-cells = <0>;
> > +	hub: genesys at 1 {
> 
> genesys: hub at 1
> 
> > +		compatible = "usb5e3,608";
> > +		reg = <1>;
> > +
> > +		power-sequence;
> > +		clocks = <&clks IMX6SX_CLK_CKO>;
> > +		reset-gpios = <&gpio4 5 GPIO_ACTIVE_LOW>; /* hub reset pin */
> > +		reset-duration-us = <10>;
> > +
> > +		#address-cells = <1>;
> > +		#size-cells = <0>;
> > +		ethernet: asix at 1 {
> 
> asix: ethernet at 1
> 
> > +			compatible = "usbb95,1708";
> > +			reg = <1>;
> > +
> > +			power-sequence;
> > +			clocks = <&clks IMX6SX_CLK_IPG>;
> > +			reset-gpios = <&gpio4 6 GPIO_ACTIVE_LOW>; /* ethernet_rst */
> > +			reset-duration-us = <15>;
> > +		};
> > +	};
> > +};

Will change, thanks.

-- 

Best Regards,
Peter Chen

[PATCH v2 0/6] power: add power sequence library

[Vaibhav Hiremath]

On Wednesday 13 July 2016 07:36 AM, Peter Chen wrote:
> Hi all,
>
> This is a follow-up for my last power sequence framework patch set [1].
> According to Rob Herring and Ulf Hansson's comments[2], I use a generic
> power sequence library for parsing the power sequence elements on DT,
> and implement generic power sequence on library. The host driver
> can allocate power sequence instance, and calls pwrseq APIs accordingly.
>
> In future, if there are special power sequence requirements, the special
> power sequence library can be created.
>
> This patch set is tested on i.mx6 sabresx evk using a dts change, I use
> two hot-plug devices to simulate this use case, the related binding
> change is updated at patch[1/6], The udoo board changes were tested
> using my last power sequence patch set.[3]
>
> Except for hard-wired MMC and USB devices, I find the USB ULPI PHY also
> need to power on itself before it can be found by ULPI bus.

Sorry being so late in the discussion...

If I am not missing anything, then I am afraid to say that the generic 
library
implementation in this patch series is not going to solve many of the custom
requirement of power on, off, etc...
I know you mentioned about adding another library when we come
across such platforms, but should we not keep provision (or easy hooks/path)
to enable that ?

Let me bring in the use case I am dealing with,


                               Host
                                  ||
                                  V
                            USB port
------------------------------------------------------------
                                  ||
                                  V
                       USB HUB device (May need custom on/off seq)
                                  ||
                                  V
               ==================
              ||                                              ||
              V                                              V
         Device-1                                Device-2
(Needs special power               (Needs special power
  on/off sequence.                       on/off sequence.
Also may need custom              Also, may need custom
sequence for                             sequence for
suspend/resume)                      suspend/resume).


Note: Both Devices are connected to HUB via HSIC and may differ
           in terms of functionality, features they support.

In the above case, both Device-1 and Device-2, need separate
power on/off sequence. So generic library currently we have in this
patch series is not going to satisfy the need here.

I looked at all 6 revisions of this patch-series, went through the
review comments, and looked at MMC power sequence code;
what I can say here is, we need something similar to
MMC power sequence here, where every device can have its own
power sequence (if needed).

I know Rob is not in favor of creating platform device for
this, and I understand his comment.
If not platform device, but atleast we need mechanism to
connect each device back to its of_node and its respective
driver/library fns. For example, the Devices may support different
boot modes, and platform driver needs to make sure that
the right sequence is followed for booting.

Peter, My apologies for taking you back again on this series.
I am OK, if you wish to address this in incremental addition,
but my point is, we know that the current generic way is not
enough for us, so I think we should try to fix it in initial phase only.


Thanks,
Vaibhav

> [1] http://www.spinics.net/lists/linux-usb/msg142755.html
> [2] http://www.spinics.net/lists/linux-usb/msg143106.html
> [3] http://www.spinics.net/lists/linux-usb/msg142815.html
>
> Changes for v2:
> - Delete "pwrseq" prefix and clock-names for properties at dt binding
> - Should use structure not but its pointer for kzalloc
> - Since chipidea core has no of_node, let core's of_node equals glue
>    layer's at core's probe
>
>
> Peter Chen (6):
>    binding-doc: power: pwrseq-generic: add binding doc for generic power
>      sequence library
>    power: add power sequence library
>    binding-doc: usb: usb-device: add optional properties for power
>      sequence
>    usb: core: add power sequence handling for USB devices
>    usb: chipidea: let chipidea core device of_node equal's glue layer
>      device of_node
>    ARM: dts: imx6qdl-udoo.dtsi: fix onboard USB HUB property
>
>   .../bindings/power/pwrseq/pwrseq-generic.txt       |  53 ++++++++
>   .../devicetree/bindings/usb/usb-device.txt         |   9 ++
>   arch/arm/boot/dts/imx6qdl-udoo.dtsi                |  27 +++--
>   drivers/power/Kconfig                              |   1 +
>   drivers/power/Makefile                             |   1 +
>   drivers/power/pwrseq/Kconfig                       |  20 +++
>   drivers/power/pwrseq/Makefile                      |   2 +
>   drivers/power/pwrseq/core.c                        |  79 ++++++++++++
>   drivers/power/pwrseq/pwrseq_generic.c              | 134 +++++++++++++++++++++
>   drivers/usb/chipidea/core.c                        |  10 ++
>   drivers/usb/core/Makefile                          |   1 +
>   drivers/usb/core/hub.c                             |  12 +-
>   drivers/usb/core/hub.h                             |  12 ++
>   drivers/usb/core/pwrseq.c                          | 102 ++++++++++++++++
>   include/linux/power/pwrseq.h                       |  55 +++++++++
>   15 files changed, 502 insertions(+), 16 deletions(-)
>   create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
>   create mode 100644 drivers/power/pwrseq/Kconfig
>   create mode 100644 drivers/power/pwrseq/Makefile
>   create mode 100644 drivers/power/pwrseq/core.c
>   create mode 100644 drivers/power/pwrseq/pwrseq_generic.c
>   create mode 100644 drivers/usb/core/pwrseq.c
>   create mode 100644 include/linux/power/pwrseq.h
>

-- 
Thanks,
Vaibhav

[PATCH v2 0/6] power: add power sequence library

[Vaibhav Hiremath]

On Tuesday 23 August 2016 03:52 PM, Vaibhav Hiremath wrote:
>
>
> On Wednesday 13 July 2016 07:36 AM, Peter Chen wrote:
>> Hi all,
>>
>> This is a follow-up for my last power sequence framework patch set [1].
>> According to Rob Herring and Ulf Hansson's comments[2], I use a generic
>> power sequence library for parsing the power sequence elements on DT,
>> and implement generic power sequence on library. The host driver
>> can allocate power sequence instance, and calls pwrseq APIs accordingly.
>>
>> In future, if there are special power sequence requirements, the special
>> power sequence library can be created.
>>
>> This patch set is tested on i.mx6 sabresx evk using a dts change, I use
>> two hot-plug devices to simulate this use case, the related binding
>> change is updated at patch[1/6], The udoo board changes were tested
>> using my last power sequence patch set.[3]
>>
>> Except for hard-wired MMC and USB devices, I find the USB ULPI PHY also
>> need to power on itself before it can be found by ULPI bus.
>
> Sorry being so late in the discussion...
>

Mistakenly responded to v2. Please ignore this, I will paste
same content on V6, which is the latest revision.

Thanks,
Vaibhav

> If I am not missing anything, then I am afraid to say that the generic 
> library
> implementation in this patch series is not going to solve many of the 
> custom
> requirement of power on, off, etc...
> I know you mentioned about adding another library when we come
> across such platforms, but should we not keep provision (or easy 
> hooks/path)
> to enable that ?
>
> Let me bring in the use case I am dealing with,
>
>
>                               Host
>                                  ||
>                                  V
>                            USB port
> ------------------------------------------------------------
>                                  ||
>                                  V
>                       USB HUB device (May need custom on/off seq)
>                                  ||
>                                  V
>               ==================
>              ||                                              ||
>              V                                              V
>         Device-1                                Device-2
> (Needs special power               (Needs special power
>  on/off sequence.                       on/off sequence.
> Also may need custom              Also, may need custom
> sequence for                             sequence for
> suspend/resume)                      suspend/resume).
>
>
> Note: Both Devices are connected to HUB via HSIC and may differ
>           in terms of functionality, features they support.
>
> In the above case, both Device-1 and Device-2, need separate
> power on/off sequence. So generic library currently we have in this
> patch series is not going to satisfy the need here.
>
> I looked at all 6 revisions of this patch-series, went through the
> review comments, and looked at MMC power sequence code;
> what I can say here is, we need something similar to
> MMC power sequence here, where every device can have its own
> power sequence (if needed).
>
> I know Rob is not in favor of creating platform device for
> this, and I understand his comment.
> If not platform device, but atleast we need mechanism to
> connect each device back to its of_node and its respective
> driver/library fns. For example, the Devices may support different
> boot modes, and platform driver needs to make sure that
> the right sequence is followed for booting.
>
> Peter, My apologies for taking you back again on this series.
> I am OK, if you wish to address this in incremental addition,
> but my point is, we know that the current generic way is not
> enough for us, so I think we should try to fix it in initial phase only.
>
>
> Thanks,
> Vaibhav
>
>> [1] http://www.spinics.net/lists/linux-usb/msg142755.html
>> [2] http://www.spinics.net/lists/linux-usb/msg143106.html
>> [3] http://www.spinics.net/lists/linux-usb/msg142815.html
>>
>> Changes for v2:
>> - Delete "pwrseq" prefix and clock-names for properties at dt binding
>> - Should use structure not but its pointer for kzalloc
>> - Since chipidea core has no of_node, let core's of_node equals glue
>>    layer's at core's probe
>>
>>
>> Peter Chen (6):
>>    binding-doc: power: pwrseq-generic: add binding doc for generic power
>>      sequence library
>>    power: add power sequence library
>>    binding-doc: usb: usb-device: add optional properties for power
>>      sequence
>>    usb: core: add power sequence handling for USB devices
>>    usb: chipidea: let chipidea core device of_node equal's glue layer
>>      device of_node
>>    ARM: dts: imx6qdl-udoo.dtsi: fix onboard USB HUB property
>>
>>   .../bindings/power/pwrseq/pwrseq-generic.txt       |  53 ++++++++
>>   .../devicetree/bindings/usb/usb-device.txt         |   9 ++
>>   arch/arm/boot/dts/imx6qdl-udoo.dtsi                |  27 +++--
>>   drivers/power/Kconfig                              |   1 +
>>   drivers/power/Makefile                             |   1 +
>>   drivers/power/pwrseq/Kconfig                       |  20 +++
>>   drivers/power/pwrseq/Makefile                      |   2 +
>>   drivers/power/pwrseq/core.c                        |  79 ++++++++++++
>>   drivers/power/pwrseq/pwrseq_generic.c              | 134 
>> +++++++++++++++++++++
>>   drivers/usb/chipidea/core.c                        |  10 ++
>>   drivers/usb/core/Makefile                          |   1 +
>>   drivers/usb/core/hub.c                             |  12 +-
>>   drivers/usb/core/hub.h                             |  12 ++
>>   drivers/usb/core/pwrseq.c                          | 102 
>> ++++++++++++++++
>>   include/linux/power/pwrseq.h                       |  55 +++++++++
>>   15 files changed, 502 insertions(+), 16 deletions(-)
>>   create mode 100644 
>> Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
>>   create mode 100644 drivers/power/pwrseq/Kconfig
>>   create mode 100644 drivers/power/pwrseq/Makefile
>>   create mode 100644 drivers/power/pwrseq/core.c
>>   create mode 100644 drivers/power/pwrseq/pwrseq_generic.c
>>   create mode 100644 drivers/usb/core/pwrseq.c
>>   create mode 100644 include/linux/power/pwrseq.h
>>
>

-- 
Thanks,
Vaibhav