[PATCH v3 2/2] phy: Add a driver for the ATH79 USB phy

From: Alban Bedel
Date: Thu Jan 28 2016 - 14:52:58 EST


The ATH79 USB phy is very simple, it only have a reset. On some SoC a
second reset is used to force the phy in suspend mode regardless of the
USB controller status.

Signed-off-by: Alban Bedel <albeu@xxxxxxx>
---
Changelog:
v2: * Rebased on the simple PHY driver
* Added myself as maintainer of the driver
---
MAINTAINERS | 8 +++
drivers/phy/Kconfig | 8 +++
drivers/phy/Makefile | 1 +
drivers/phy/phy-ath79-usb.c | 116 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 133 insertions(+)
create mode 100644 drivers/phy/phy-ath79-usb.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 30aca4a..f536d52 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1866,6 +1866,14 @@ S: Maintained
F: drivers/gpio/gpio-ath79.c
F: Documentation/devicetree/bindings/gpio/gpio-ath79.txt

+ATHEROS 71XX/9XXX USB PHY DRIVER
+M: Alban Bedel <albeu@xxxxxxx>
+W: https://github.com/AlbanBedel/linux
+T: git git://github.com/AlbanBedel/linux
+S: Maintained
+F: drivers/phy/phy-ath79-usb.c
+F: Documentation/devicetree/bindings/phy/phy-ath79-usb.txt
+
ATHEROS ATH GENERIC UTILITIES
M: "Luis R. Rodriguez" <mcgrof@xxxxxxxxxxxxxxxx>
L: linux-wireless@xxxxxxxxxxxxxxx
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index efbaee4..6090c63 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -15,6 +15,14 @@ config GENERIC_PHY
phy users can obtain reference to the PHY. All the users of this
framework should select this config.

+config PHY_ATH79_USB
+ tristate "Atheros AR71XX/9XXX USB PHY driver"
+ depends on ATH79 || COMPILE_TEST
+ default y if USB_EHCI_HCD_PLATFORM
+ select PHY_SIMPLE
+ help
+ Enable this to support the USB PHY on Atheros AR71XX/9XXX SoCs.
+
config PHY_BERLIN_USB
tristate "Marvell Berlin USB PHY Driver"
depends on ARCH_BERLIN && RESET_CONTROLLER && HAS_IOMEM && OF
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 1cc7268..5c9ca5f 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -3,6 +3,7 @@
#

obj-$(CONFIG_GENERIC_PHY) += phy-core.o
+obj-$(CONFIG_PHY_ATH79_USB) += phy-ath79-usb.o
obj-$(CONFIG_PHY_BERLIN_USB) += phy-berlin-usb.o
obj-$(CONFIG_PHY_BERLIN_SATA) += phy-berlin-sata.o
obj-$(CONFIG_PHY_DM816X_USB) += phy-dm816x-usb.o
diff --git a/drivers/phy/phy-ath79-usb.c b/drivers/phy/phy-ath79-usb.c
new file mode 100644
index 0000000..ff49356
--- /dev/null
+++ b/drivers/phy/phy-ath79-usb.c
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2015 Alban Bedel <albeu@xxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/phy/simple.h>
+#include <linux/reset.h>
+
+struct ath79_usb_phy {
+ struct simple_phy sphy;
+ struct reset_control *suspend_override;
+};
+
+static int ath79_usb_phy_power_on(struct phy *phy)
+{
+ struct ath79_usb_phy *priv = container_of(
+ phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
+ int err;
+
+ err = simple_phy_power_on(phy);
+ if (err)
+ return err;
+
+ if (priv->suspend_override) {
+ err = reset_control_assert(priv->suspend_override);
+ if (err) {
+ simple_phy_power_off(phy);
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static int ath79_usb_phy_power_off(struct phy *phy)
+{
+ struct ath79_usb_phy *priv = container_of(
+ phy_get_drvdata(phy), struct ath79_usb_phy, sphy);
+ int err;
+
+ if (priv->suspend_override) {
+ err = reset_control_deassert(priv->suspend_override);
+ if (err)
+ return err;
+ }
+
+ err = simple_phy_power_off(phy);
+ if (err && priv->suspend_override)
+ reset_control_assert(priv->suspend_override);
+
+ return err;
+}
+
+static const struct phy_ops ath79_usb_phy_ops = {
+ .power_on = ath79_usb_phy_power_on,
+ .power_off = ath79_usb_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static const struct simple_phy_desc ath79_usb_phy_desc = {
+ .ops = &ath79_usb_phy_ops,
+ .reset = "usb-phy",
+ .clk = (void *)-ENOENT,
+};
+
+static int ath79_usb_phy_probe(struct platform_device *pdev)
+{
+ struct ath79_usb_phy *priv;
+ struct phy *phy;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->suspend_override = devm_reset_control_get_optional(
+ &pdev->dev, "usb-suspend-override");
+ if (IS_ERR(priv->suspend_override)) {
+ if (PTR_ERR(priv->suspend_override) == -ENOENT)
+ priv->suspend_override = NULL;
+ else
+ return PTR_ERR(priv->suspend_override);
+ }
+
+ phy = devm_simple_phy_create(&pdev->dev,
+ &ath79_usb_phy_desc, &priv->sphy);
+ if (IS_ERR(phy))
+ return PTR_ERR(phy);
+
+ return PTR_ERR_OR_ZERO(devm_of_phy_provider_register(
+ &pdev->dev, of_phy_simple_xlate));
+}
+
+static const struct of_device_id ath79_usb_phy_of_match[] = {
+ { .compatible = "qca,ar7100-usb-phy" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ath79_usb_phy_of_match);
+
+static struct platform_driver ath79_usb_phy_driver = {
+ .probe = ath79_usb_phy_probe,
+ .driver = {
+ .of_match_table = ath79_usb_phy_of_match,
+ .name = "ath79-usb-phy",
+ }
+};
+module_platform_driver(ath79_usb_phy_driver);
+
+MODULE_DESCRIPTION("ATH79 USB PHY driver");
+MODULE_AUTHOR("Alban Bedel <albeu@xxxxxxx>");
+MODULE_LICENSE("GPL");
--
2.0.0