[PATCH v3 1/2] phy: Add a driver for simple phy

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


This driver is meant to take care of all trivial phys that don't need
any special configuration, it just enable a regulator, a clock and
deassert a reset. A public API is also included to allow re-using the
code in other drivers.

Signed-off-by: Alban Bedel <albeu@xxxxxxx>
---
drivers/phy/Kconfig | 12 +++
drivers/phy/Makefile | 1 +
drivers/phy/phy-simple.c | 204 +++++++++++++++++++++++++++++++++++++++++++++
include/linux/phy/simple.h | 39 +++++++++
4 files changed, 256 insertions(+)
create mode 100644 drivers/phy/phy-simple.c
create mode 100644 include/linux/phy/simple.h

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index e7e117d..efbaee4 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -125,6 +125,18 @@ config PHY_RCAR_GEN3_USB2
help
Support for USB 2.0 PHY found on Renesas R-Car generation 3 SoCs.

+config PHY_SIMPLE
+ tristate
+ select GENERIC_PHY
+ help
+
+config PHY_SIMPLE_PDEV
+ tristate "Simple PHY driver"
+ select PHY_SIMPLE
+ help
+ A PHY driver for simple devices that only need a regulator, clock
+ and reset for power up and shutdown.
+
config OMAP_CONTROL_PHY
tristate "OMAP CONTROL PHY Driver"
depends on ARCH_OMAP2PLUS || COMPILE_TEST
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index c80f09d..1cc7268 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_PHY_EXYNOS5250_SATA) += phy-exynos5250-sata.o
obj-$(CONFIG_PHY_HIX5HD2_SATA) += phy-hix5hd2-sata.o
obj-$(CONFIG_PHY_HI6220_USB) += phy-hi6220-usb.o
obj-$(CONFIG_PHY_MT65XX_USB3) += phy-mt65xx-usb3.o
+obj-$(CONFIG_PHY_SIMPLE) += phy-simple.o
obj-$(CONFIG_PHY_SUN4I_USB) += phy-sun4i-usb.o
obj-$(CONFIG_PHY_SUN9I_USB) += phy-sun9i-usb.o
obj-$(CONFIG_PHY_SAMSUNG_USB2) += phy-exynos-usb2.o
diff --git a/drivers/phy/phy-simple.c b/drivers/phy/phy-simple.c
new file mode 100644
index 0000000..013f846
--- /dev/null
+++ b/drivers/phy/phy-simple.c
@@ -0,0 +1,204 @@
+/*
+ * 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/of_device.h>
+#include <linux/phy/simple.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+
+int simple_phy_power_on(struct phy *phy)
+{
+ struct simple_phy *sphy = phy_get_drvdata(phy);
+ int err;
+
+ if (sphy->regulator) {
+ err = regulator_enable(sphy->regulator);
+ if (err)
+ return err;
+ }
+
+ if (sphy->clk) {
+ err = clk_prepare_enable(sphy->clk);
+ if (err)
+ goto regulator_disable;
+ }
+
+ if (sphy->reset) {
+ err = reset_control_deassert(sphy->reset);
+ if (err)
+ goto clock_disable;
+ }
+
+ return 0;
+
+clock_disable:
+ if (sphy->clk)
+ clk_disable_unprepare(sphy->clk);
+regulator_disable:
+ if (sphy->regulator)
+ WARN_ON(regulator_disable(sphy->regulator));
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(simple_phy_power_on);
+
+int simple_phy_power_off(struct phy *phy)
+{
+ struct simple_phy *sphy = phy_get_drvdata(phy);
+ int err;
+
+ if (sphy->reset) {
+ err = reset_control_assert(sphy->reset);
+ if (err)
+ return err;
+ }
+
+ if (sphy->clk)
+ clk_disable_unprepare(sphy->clk);
+
+ if (sphy->regulator) {
+ err = regulator_disable(sphy->regulator);
+ if (err)
+ goto clock_enable;
+ }
+
+ return 0;
+
+clock_enable:
+ if (sphy->clk)
+ WARN_ON(clk_prepare_enable(sphy->clk));
+ if (sphy->reset)
+ WARN_ON(reset_control_deassert(sphy->reset));
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(simple_phy_power_off);
+
+static const struct phy_ops simple_phy_ops = {
+ .power_on = simple_phy_power_on,
+ .power_off = simple_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+struct phy *devm_simple_phy_create(struct device *dev,
+ const struct simple_phy_desc *desc,
+ struct simple_phy *sphy)
+{
+ struct phy *phy;
+
+ if (!dev || !desc)
+ return ERR_PTR(-EINVAL);
+
+ if (!sphy) {
+ sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
+ if (!sphy)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ if (!IS_ERR_OR_NULL(desc->regulator)) {
+ sphy->regulator = devm_regulator_get(dev, desc->regulator);
+ if (IS_ERR(sphy->regulator)) {
+ if (PTR_ERR(sphy->regulator) == -ENOENT)
+ sphy->regulator = NULL;
+ else
+ return ERR_PTR(PTR_ERR(sphy->regulator));
+ }
+ }
+
+ if (!IS_ERR(desc->clk)) {
+ sphy->clk = devm_clk_get(dev, desc->clk);
+ if (IS_ERR(sphy->clk)) {
+ if (PTR_ERR(sphy->clk) == -ENOENT)
+ sphy->clk = NULL;
+ else
+ return ERR_PTR(PTR_ERR(sphy->clk));
+ }
+ }
+
+ if (!IS_ERR(desc->reset)) {
+ sphy->reset = devm_reset_control_get(dev, desc->reset);
+ if (IS_ERR(sphy->reset)) {
+ int err = PTR_ERR(sphy->reset);
+
+ if (err == -ENOENT || err == -ENOTSUPP)
+ sphy->reset = NULL;
+ else
+ return ERR_PTR(err);
+ }
+ }
+
+ phy = devm_phy_create(dev, NULL, desc->ops ?: &simple_phy_ops);
+ if (IS_ERR(phy))
+ return ERR_PTR(PTR_ERR(phy));
+
+ phy_set_drvdata(phy, sphy);
+
+ return phy;
+}
+EXPORT_SYMBOL_GPL(devm_simple_phy_create);
+
+#ifdef CONFIG_PHY_SIMPLE_PDEV
+#ifdef CONFIG_OF
+/* Default config, no regulator, default clock and reset if any */
+static const struct simple_phy_desc simple_phy_default_desc = {};
+
+static const struct of_device_id simple_phy_of_match[] = {
+ { .compatible = "simple-phy", .data = &simple_phy_default_desc },
+ {}
+};
+MODULE_DEVICE_TABLE(of, simple_phy_of_match);
+
+const struct simple_phy_desc *simple_phy_get_of_desc(struct device *dev)
+{
+ const struct of_device_id *match;
+
+ match = of_match_device(simple_phy_of_match, dev);
+
+ return match ? match->data : NULL;
+}
+#else
+const struct simple_phy_desc *simple_phy_get_of_desc(struct device *dev)
+{
+ return NULL;
+}
+#endif
+
+static int simple_phy_probe(struct platform_device *pdev)
+{
+ const struct simple_phy_desc *desc = pdev->dev.platform_data;
+ struct phy *phy;
+
+ if (!desc)
+ desc = simple_phy_get_of_desc(&pdev->dev);
+ if (!desc)
+ return -EINVAL;
+
+ phy = devm_simple_phy_create(&pdev->dev, desc, NULL);
+ 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 struct platform_driver simple_phy_driver = {
+ .probe = simple_phy_probe,
+ .driver = {
+ .of_match_table = of_match_ptr(simple_phy_of_match),
+ .name = "phy-simple",
+ }
+};
+module_platform_driver(simple_phy_driver);
+
+#endif /* CONFIG_PHY_SIMPLE_PDEV */
+
+MODULE_DESCRIPTION("Simple PHY driver");
+MODULE_AUTHOR("Alban Bedel <albeu@xxxxxxx>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/phy/simple.h b/include/linux/phy/simple.h
new file mode 100644
index 0000000..f368b57
--- /dev/null
+++ b/include/linux/phy/simple.h
@@ -0,0 +1,39 @@
+/*
+ * 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.
+ */
+
+#ifndef __LINUX_PHY_SIMPLE__
+#define __LINUX_PHY_SIMPLE__
+
+#include <linux/phy/phy.h>
+
+struct reset_control;
+struct clk;
+
+struct simple_phy {
+ struct regulator *regulator;
+ struct reset_control *reset;
+ struct clk *clk;
+};
+
+struct simple_phy_desc {
+ const struct phy_ops *ops;
+ const char *regulator;
+ const char *reset;
+ const char *clk;
+};
+
+struct phy *devm_simple_phy_create(struct device *dev,
+ const struct simple_phy_desc *desc,
+ struct simple_phy *sphy);
+
+int simple_phy_power_on(struct phy *phy);
+
+int simple_phy_power_off(struct phy *phy);
+
+#endif /* __LINUX_PHY_SIMPLE__ */
--
2.0.0