[U-Boot] [PATCH v4 2/7] drivers: phy: add generic PHY framework
Jean-Jacques Hiblot
jjhiblot at ti.com
Fri Apr 21 10:08:46 UTC 2017
The PHY framework provides a set of APIs to control a PHY. This API is
derived from the linux version of the generic PHY framework.
Currently the API supports init(), deinit(), power_on, power_off() and
reset(). The framework provides a way to get a reference to a phy from the
device-tree.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot at ti.com>
---
changes since v3:
* make it possible for a phy device to handle multiple ports. The consequence
is the intruction of struct phy which is is used as a parameter to all the
functions of the API.
* Add generic_phy_get_by_index() and generic_phy_get_by_name() to get a reference
to a phy port. Removed dm_generic_phy_get().
* Improved the documentation
drivers/Kconfig | 2 +
drivers/Makefile | 2 +
drivers/phy/Kconfig | 36 ++++++++
drivers/phy/Makefile | 2 +
drivers/phy/phy-uclass.c | 139 +++++++++++++++++++++++++++++
include/dm/uclass-id.h | 1 +
include/generic-phy.h | 224 +++++++++++++++++++++++++++++++++++++++++++++++
7 files changed, 406 insertions(+)
create mode 100644 drivers/phy/Kconfig
create mode 100644 drivers/phy/Makefile
create mode 100644 drivers/phy/phy-uclass.c
create mode 100644 include/generic-phy.h
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 3e6bbac..1fe5baf 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -90,6 +90,8 @@ source "drivers/video/Kconfig"
source "drivers/watchdog/Kconfig"
+source "drivers/phy/Kconfig"
+
config PHYS_TO_BUS
bool "Custom physical to bus address mapping"
help
diff --git a/drivers/Makefile b/drivers/Makefile
index 5d8baa5..c2700a0 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -5,9 +5,11 @@
obj-$(CONFIG_$(SPL_TPL_)DM) += core/
obj-$(CONFIG_$(SPL_)CLK) += clk/
obj-$(CONFIG_$(SPL_)LED) += led/
+obj-$(CONFIG_$(SPL_)PHY) += phy/
obj-$(CONFIG_$(SPL_)PINCTRL) += pinctrl/
obj-$(CONFIG_$(SPL_)RAM) += ram/
+
ifdef CONFIG_SPL_BUILD
obj-$(CONFIG_SPL_CPU_SUPPORT) += cpu/
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
new file mode 100644
index 0000000..0a74920
--- /dev/null
+++ b/drivers/phy/Kconfig
@@ -0,0 +1,36 @@
+
+menu "PHY Subsystem"
+
+config PHY
+ bool "PHY Core"
+ depends on DM
+ help
+ PHY support.
+
+ This framework is designed to provide a generic interface for PHY
+ devices. PHY devices are dedicated hardware that handle the physical
+ layer of the protocols in the OSI model.
+ PHYs are commonly used for high speed interfaces such as Serial-ATA
+ or PCI express.
+ The API provides functions to initialize/deinitialize the
+ PHY, power on/off the PHY, and reset the PHY. It's meant to be as
+ compatible as possible with the equivalent framework found in the
+ linux kernel.
+
+config SPL_PHY
+ bool "PHY Core in SPL"
+ depends on DM
+ help
+ PHY support in SPL.
+
+ This framework is designed to provide a generic interface for PHY
+ devices. PHY devices are dedicated hardware that handle the physical
+ layer of the protocols (https://en.wikipedia.org/wiki/OSI_model).
+ PHYs are commonly used for high speed interfaces such as Serial-ATA
+ or PCI express.
+ The API provides functions to initialize/deinitialize the
+ PHY, power on/off the PHY, and reset the PHY. It's meant to be as
+ compatible as possible with the equivalent framework found in the
+ linux kernel.
+
+endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
new file mode 100644
index 0000000..186f07d
--- /dev/null
+++ b/drivers/phy/Makefile
@@ -0,0 +1,2 @@
+obj-$(CONFIG_$(SPL_)PHY) += phy-uclass.o
+
diff --git a/drivers/phy/phy-uclass.c b/drivers/phy/phy-uclass.c
new file mode 100644
index 0000000..0d8bef7
--- /dev/null
+++ b/drivers/phy/phy-uclass.c
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com/
+ * Written by Jean-Jacques Hiblot <jjhiblot at ti.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <generic-phy.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static inline struct phy_ops *phy_dev_ops(struct udevice *dev)
+{
+ return (struct phy_ops *)dev->driver->ops;
+}
+
+static int generic_phy_xlate_offs_flags(struct phy *phy,
+ struct fdtdec_phandle_args *args)
+{
+ debug("%s(phy=%p)\n", __func__, phy);
+
+ if (args->args_count > 1) {
+ debug("Invaild args_count: %d\n", args->args_count);
+ return -EINVAL;
+ }
+
+ if (args->args_count)
+ phy->id = args->args[0];
+ else
+ phy->id = 0;
+
+
+ return 0;
+}
+
+int generic_phy_get_by_index(struct udevice *dev, int index,
+ struct phy *phy)
+{
+ struct fdtdec_phandle_args args;
+ struct phy_ops *ops;
+ int ret;
+ struct udevice *phydev;
+
+ debug("%s(dev=%p, index=%d, phy=%p)\n", __func__, dev, index, phy);
+
+ assert(phy);
+ ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev_of_offset(dev),
+ "phys", "#phy-cells", 0, index,
+ &args);
+ if (ret) {
+ debug("%s: fdtdec_parse_phandle_with_args failed: err=%d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ ret = uclass_get_device_by_of_offset(UCLASS_PHY, args.node, &phydev);
+ if (ret) {
+ debug("%s: uclass_get_device_by_of_offset failed: err=%d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ phy->dev = phydev;
+
+ ops = phy_dev_ops(phydev);
+
+ if (ops->of_xlate)
+ ret = ops->of_xlate(phy, &args);
+ else
+ ret = generic_phy_xlate_offs_flags(phy, &args);
+ if (ret) {
+ debug("of_xlate() failed: %d\n", ret);
+ goto err;
+ }
+
+ return 0;
+
+err:
+ return ret;
+}
+
+int generic_phy_get_by_name(struct udevice *dev, const char *phy_name,
+ struct phy *phy)
+{
+ int index;
+
+ debug("%s(dev=%p, name=%s, phy=%p)\n", __func__, dev, phy_name, phy);
+
+ index = fdt_stringlist_search(gd->fdt_blob, dev_of_offset(dev),
+ "phy-names", phy_name);
+ if (index < 0) {
+ debug("fdt_stringlist_search() failed: %d\n", index);
+ return index;
+ }
+
+ return generic_phy_get_by_index(dev, index, phy);
+}
+
+int generic_phy_init(struct phy *phy)
+{
+ struct phy_ops const *ops = phy_dev_ops(phy->dev);
+
+ return ops->init ? ops->init(phy) : 0;
+}
+
+int generic_phy_reset(struct phy *phy)
+{
+ struct phy_ops const *ops = phy_dev_ops(phy->dev);
+
+ return ops->reset ? ops->reset(phy) : 0;
+}
+
+int generic_phy_exit(struct phy *phy)
+{
+ struct phy_ops const *ops = phy_dev_ops(phy->dev);
+
+ return ops->exit ? ops->exit(phy) : 0;
+}
+
+int generic_phy_power_on(struct phy *phy)
+{
+ struct phy_ops const *ops = phy_dev_ops(phy->dev);
+
+ return ops->power_on ? ops->power_on(phy) : 0;
+}
+
+int generic_phy_power_off(struct phy *phy)
+{
+ struct phy_ops const *ops = phy_dev_ops(phy->dev);
+
+ return ops->power_off ? ops->power_off(phy) : 0;
+}
+
+UCLASS_DRIVER(phy) = {
+ .id = UCLASS_PHY,
+ .name = "phy",
+};
diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h
index 8c92d0b..996e94f 100644
--- a/include/dm/uclass-id.h
+++ b/include/dm/uclass-id.h
@@ -83,6 +83,7 @@ enum uclass_id {
UCLASS_VIDEO, /* Video or LCD device */
UCLASS_VIDEO_BRIDGE, /* Video bridge, e.g. DisplayPort to LVDS */
UCLASS_VIDEO_CONSOLE, /* Text console driver for video device */
+ UCLASS_PHY, /* Physical Layer (PHY) device */
UCLASS_COUNT,
UCLASS_INVALID = -1,
diff --git a/include/generic-phy.h b/include/generic-phy.h
new file mode 100644
index 0000000..d8cf0c9
--- /dev/null
+++ b/include/generic-phy.h
@@ -0,0 +1,224 @@
+/*
+ * Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com/
+ * Written by Jean-Jacques Hiblot <jjhiblot at ti.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef __GENERIC_PHY_H
+#define __GENERIC_PHY_H
+
+
+/**
+ * struct phy - A handle to (allowing control of) a single phy port.
+ *
+ * Clients provide storage for phy handles. The content of the structure is
+ * managed solely by the PHY API and PHY drivers. A phy struct is
+ * initialized by "get"ing the phy struct. The phy struct is passed to all
+ * other phy APIs to identify which PHY port to operate upon.
+ *
+ * @dev: The device which implements the PHY port.
+ * @id: The PHY ID within the provider.
+ *
+ */
+struct phy {
+ struct udevice *dev;
+ unsigned long id;
+};
+
+/*
+ * struct udevice_ops - set of function pointers for phy operations
+ * @init: operation to be performed for initializing phy (optional)
+ * @exit: operation to be performed while exiting (optional)
+ * @reset: reset the phy (optional).
+ * @power_on: powering on the phy (optional)
+ * @power_off: powering off the phy (optional)
+ */
+struct phy_ops {
+ /**
+ * of_xlate - Translate a client's device-tree (OF) phy specifier.
+ *
+ * The PHY core calls this function as the first step in implementing
+ * a client's generic_phy_get_by_*() call.
+ *
+ * If this function pointer is set to NULL, the PHY core will use a
+ * default implementation, which assumes #phy-cells = <0> or
+ * #phy-cells = <1>, and in the later case that the DT cell
+ * contains a simple integer PHY port ID.
+ *
+ * @phy: The phy struct to hold the translation result.
+ * @args: The phy specifier values from device tree.
+ * @return 0 if OK, or a negative error code.
+ */
+ int (*of_xlate)(struct phy *phy,
+ struct fdtdec_phandle_args *args);
+
+ /**
+ * init - initialize the hardware.
+ *
+ * Hardware intialization should not be done in during probe() but
+ * should be implemented in this init() function. It could be starting
+ * PLL, taking a controller out of reset, routing, etc. This function
+ * is typically called only once per PHY port.
+ * If power_on() is not implemented, it must power up the phy.
+ *
+ * @phy: the PHY port to initialize
+ * @return 0 if OK, or a negative error code.
+ */
+ int (*init)(struct phy *phy);
+
+ /**
+ * exit - de-initialize the PHY device
+ *
+ * Hardware de-intialization should be done here. Every step done in
+ * init() should be undone here.
+ * This could be used to suspend the phy to reduce power consumption or
+ * to put the phy in a known condition before booting the OS (though it
+ * is NOT called automatically before booting the OS)
+ * If power_off() is not implemented, it must power down the phy.
+ *
+ * @phy: PHY port to be de-initialized
+ * @return 0 if OK, or a negative error code
+ */
+ int (*exit)(struct phy *phy);
+
+ /**
+ * reset - resets a PHY device without shutting down
+ *
+ * @phy: PHY port to be reset
+ *
+ * During runtime, the PHY may need to be reset in order to
+ * re-establish connection etc without being shut down or exit.
+ *
+ * @return 0 if OK, or a negative error code
+ */
+ int (*reset)(struct phy *phy);
+
+ /**
+ * power_on - power on a PHY device
+ *
+ * @phy: PHY port to be powered on
+ *
+ * During runtime, the PHY may need to be powered on or off several
+ * times. This function is used to power on the PHY. It relies on the
+ * setup done in init(). If init() is not implemented, it must take care
+ * of setting up the context (PLLs, ...)
+ *
+ * @return 0 if OK, or a negative error code
+ */
+ int (*power_on)(struct phy *phy);
+
+ /**
+ * power_off - power off a PHY device
+ *
+ * @phy: PHY port to be powered off
+ *
+ * During runtime, the PHY may need to be powered on or off several
+ * times. This function is used to power off the PHY. Except if
+ * init()/deinit() are not implemented, it must not de-initialize
+ * everything.
+ *
+ * @return 0 if OK, or a negative error code
+ */
+ int (*power_off)(struct phy *phy);
+};
+
+
+/**
+ * generic_phy_init() - initialize the PHY port
+ *
+ * @phy: the PHY port to initialize
+ * @return 0 if OK, or a negative error code
+ */
+int generic_phy_init(struct phy *phy);
+
+/**
+ * generic_phy_init() - de-initialize the PHY device
+ *
+ * @phy: PHY port to be de-initialized
+ * @return 0 if OK, or a negative error code
+ */
+int generic_phy_exit(struct phy *phy);
+
+/**
+ * generic_phy_reset() - resets a PHY device without shutting down
+ *
+ * @phy: PHY port to be reset
+ *@return 0 if OK, or a negative error code
+ */
+int generic_phy_reset(struct phy *phy);
+
+/**
+ * generic_phy_power_on() - power on a PHY device
+ *
+ * @phy: PHY port to be powered on
+ * @return 0 if OK, or a negative error code
+ */
+int generic_phy_power_on(struct phy *phy);
+
+/**
+ * generic_phy_power_off() - power off a PHY device
+ *
+ * @phy: PHY port to be powered off
+ * @return 0 if OK, or a negative error code
+ */
+int generic_phy_power_off(struct phy *phy);
+
+
+/**
+ * generic_phy_get_by_index() - Get a PHY device by integer index.
+ *
+ * @user: the client device
+ * @index: The index in the list of available PHYs
+ * @phy: A pointer to the PHY port
+ *
+ * This looks up a PHY device for a client device based on its position in the
+ * list of the possible PHYs.
+ *
+ * example:
+ * usb1: usb_otg_ss at xxx {
+ * compatible = "xxx";
+ * reg = <xxx>;
+ * .
+ * .
+ * phys = <&usb2_phy>, <&usb3_phy>;
+ * .
+ * .
+ * };
+ * the USB2 phy can be accessed by passing index '0' and the USB3 phy can
+ * be accessed by passing index '1'
+ *
+ * @return 0 if OK, or a negative error code
+ */
+int generic_phy_get_by_index(struct udevice *user, int index,
+ struct phy *phy);
+
+/**
+ * generic_phy_get_by_name() - Get a PHY device by its name.
+ *
+ * @user: the client device
+ * @phy_name: The name of the PHY in the list of possible PHYs
+ * @phy: A pointer to the PHY port
+ *
+ * This looks up a PHY device for a client device in the
+ * list of the possible PHYs based on its name.
+ *
+ * example:
+ * usb1: usb_otg_ss at xxx {
+ * compatible = "xxx";
+ * reg = <xxx>;
+ * .
+ * .
+ * phys = <&usb2_phy>, <&usb3_phy>;
+ * phy-names = "usb2phy", "usb3phy";
+ * .
+ * .
+ * };
+ * the USB3 phy can be accessed using "usb3phy", and USB2 by using "usb2phy"
+ *
+ * @return 0 if OK, or a negative error code
+ */
+int generic_phy_get_by_name(struct udevice *user, const char *phy_name,
+ struct phy *phy);
+
+#endif /*__GENERIC_PHY_H */
--
1.9.1
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