Re: [PATCH v6 1/9] drivers: phy: add generic PHY framework

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

On Tuesday 04 June 2013 03:51 PM, Sylwester Nawrocki wrote:
On 04/29/2013 12:03 PM, Kishon Vijay Abraham I wrote:
The PHY framework provides a set of APIs for the PHY drivers to
create/destroy a PHY and APIs for the PHY users to obtain a reference to the
PHY with or without using phandle. For dt-boot, the PHY drivers should
also register *PHY provider* with the framework.

PHY drivers should create the PHY by passing id and ops like init, exit,
power_on and power_off. This framework is also pm runtime enabled.

The documentation for the generic PHY framework is added in
Documentation/phy.txt and the documentation for dt binding can be found at
Documentation/devicetree/bindings/phy/phy-bindings.txt

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
  .../devicetree/bindings/phy/phy-bindings.txt       |   66 +++
  Documentation/phy.txt                              |  123 +++++
  MAINTAINERS                                        |    7 +
  drivers/Kconfig                                    |    2 +
  drivers/Makefile                                   |    2 +
  drivers/phy/Kconfig                                |   13 +
  drivers/phy/Makefile                               |    5 +
  drivers/phy/phy-core.c                             |  539 ++++++++++++++++++++
  include/linux/phy/phy.h                            |  248 +++++++++
  9 files changed, 1005 insertions(+)
  create mode 100644 Documentation/devicetree/bindings/phy/phy-bindings.txt
  create mode 100644 Documentation/phy.txt
  create mode 100644 drivers/phy/Kconfig
  create mode 100644 drivers/phy/Makefile
  create mode 100644 drivers/phy/phy-core.c
  create mode 100644 include/linux/phy/phy.h

+static inline int phy_init(struct phy *phy)
+{
+	pm_runtime_get_sync(&phy->dev);

Hmm, no need to check return value here ? Also it looks a bit unexpected to

I purposely dint check the return values in order to support platforms that don’t enable pm_runtime.
possibly have runtime_resume callback of a PHY device called before ops->init()
call ? It seems a bit unclear what the purpose of init() callback is.

Not really. Anything that is used to initialize the PHY (internal configuration) can go in phy_init. Usually in runtime_resume callback, optional functional clocks are enabled and also in some cases context restore is done. So it really makes sense to enable clocks/module (pm_runtime_get_sync) before doing a PHY configuration (phy_init).


+	if (phy->ops->init)
+		return phy->ops->init(phy);
+
+	return -EINVAL;
+}
+
+static inline int phy_exit(struct phy *phy)
+{
+	int ret = -EINVAL;
+
+	if (phy->ops->exit)
+		ret = phy->ops->exit(phy);
+
+	pm_runtime_put_sync(&phy->dev);
+
+	return ret;
+}

Do phy_init/phy_exit need to be mandatory ? What if there is really

No. phy_init/phy_exit is not mandatory at all.
nothing to do in those callbacks ? Perhaps -ENOIOCTLCMD should be
returned if a callback is not implemented, so PHY users can recognize
such situation and proceed ?

So currently these APIs return -EINVAL if these callbacks are not populated which is good enough IMHO.

+static inline int phy_power_on(struct phy *phy)
+{
+	if (phy->ops->power_on)
+		return phy->ops->power_on(phy);
+
+	return -EINVAL;
+}
+
+static inline int phy_power_off(struct phy *phy)
+{
+	if (phy->ops->power_off)
+		return phy->ops->power_off(phy);
+
+	return -EINVAL;
+}
+
+static inline int phy_pm_runtime_get(struct phy *phy)
+{
+	if (WARN(IS_ERR(phy), "Invalid PHY reference\n"))
+		return -EINVAL;
+
+	return pm_runtime_get(&phy->dev);
+}
+
+static inline int phy_pm_runtime_get_sync(struct phy *phy)
+{
+	if (WARN(IS_ERR(phy), "Invalid PHY reference\n"))
+		return -EINVAL;
+
+	return pm_runtime_get_sync(&phy->dev);
+}
+
+static inline int phy_pm_runtime_put(struct phy *phy)
+{
+	if (WARN(IS_ERR(phy), "Invalid PHY reference\n"))
+		return -EINVAL;
+
+	return pm_runtime_put(&phy->dev);
+}
+
+static inline int phy_pm_runtime_put_sync(struct phy *phy)
+{
+	if (WARN(IS_ERR(phy), "Invalid PHY reference\n"))
+		return -EINVAL;
+
+	return pm_runtime_put_sync(&phy->dev);
+}
+
+static inline void phy_pm_runtime_allow(struct phy *phy)
+{
+	if (WARN(IS_ERR(phy), "Invalid PHY reference\n"))
+		return;
+
+	pm_runtime_allow(&phy->dev);
+}
+
+static inline void phy_pm_runtime_forbid(struct phy *phy)
+{
+	if (WARN(IS_ERR(phy), "Invalid PHY reference\n"))
+		return;
+
+	pm_runtime_forbid(&phy->dev);
+}

Do we need to have all these runtime PM wrappers ? I guess you
intended to avoid referencing phy->dev from the PHY consumers ?

Yeah.. I dint want pm_runtime of phy core device to be called from PHY consumers.

Thanks
Kishon
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html




[Index of Archives]     [Linux Arm (vger)]     [ARM Kernel]     [ARM MSM]     [Linux Tegra]     [Linux WPAN Networking]     [Linux Wireless Networking]     [Maemo Users]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux