[PATCH v2 1/4] phy: phy-stih407-usb: Add usb picoPHY driver found on stih407 SoC family

Peter Griffin
2014-09-09T09:00:15Z

This is the generic phy driver for the picoPHY ports used by the
USB2 and USB3 Host controllers when controlling usb2/1.1 devices. It
is found on STiH407 SoC family from STMicroelectronics.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
---
drivers/phy/Kconfig | 8 ++
drivers/phy/Makefile | 2 +
drivers/phy/phy-stih407-usb.c | 185 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 195 insertions(+)
create mode 100644 drivers/phy/phy-stih407-usb.c

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 0dd7427..58018f7 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -230,4 +230,12 @@ config PHY_XGENE
help
This option enables support for APM X-Gene SoC multi-purpose PHY.

+config PHY_STIH407_USB
+ tristate "STMicroelectronics USB2 picoPHY driver for STiH407 family"
+ depends on ARCH_STI
+ depends on GENERIC_PHY
+ help
+ Enable this support to enable the picoPHY device used by USB2
+ and USB3 controllers on STMicroelectronics STiH407 SoC families.
+
endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 95c69ed..c82ac59 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -28,3 +28,5 @@ obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA) += phy-qcom-ipq806x-sata.o
obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY) += phy-spear1310-miphy.o
obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY) += phy-spear1340-miphy.o
obj-$(CONFIG_PHY_XGENE) += phy-xgene.o
+obj-$(CONFIG_PHY_STIH407_USB) += phy-stih407-usb.o
+
diff --git a/drivers/phy/phy-stih407-usb.c b/drivers/phy/phy-stih407-usb.c
new file mode 100644
index 0000000..8019e3b
--- /dev/null
+++ b/drivers/phy/phy-stih407-usb.c
@@ -0,0 +1,185 @@
+/*
+ * Copyright (C) 2014 STMicroelectronics
+ *
+ * STMicroelectronics Generic PHY driver for STiH407 USB2.
+ *
+ * Author: Giuseppe Cavallaro <peppe.cavallaro@st.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, as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/clk.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/mfd/syscon.h>
+#include <linux/phy/phy.h>
+
+/* Default PHY_SEL and REFCLKSEL configuration */
+#define STIH407_USB_PICOPHY_CTRL_PORT_CONF 0x6
+#define STIH407_USB_PICOPHY_CTRL_PORT_MASK 0x1f
+
+/* ports parameters overriding */
+#define STIH407_USB_PICOPHY_PARAM_DEF 0x39a4dc
+#define STIH407_USB_PICOPHY_PARAM_MASK 0xffffffff
+
+struct stih407_usb2_picophy {
+ struct phy *phy;
+ struct regmap *regmap;
+ struct device *dev;
+ struct reset_control *rstc;
+ struct reset_control *rstport;
+ int ctrl;
+ int param;
+};
+
+static int stih407_usb2_pico_ctrl(struct stih407_usb2_picophy *phy_dev)
+{
+ reset_control_deassert(phy_dev->rstc);
+
+ return regmap_update_bits(phy_dev->regmap, phy_dev->ctrl,
+ STIH407_USB_PICOPHY_CTRL_PORT_MASK,
+ STIH407_USB_PICOPHY_CTRL_PORT_CONF);
+}
+
+static int stih407_usb2_init_port(struct phy *phy)
+{
+ int ret;
+ struct stih407_usb2_picophy *phy_dev = phy_get_drvdata(phy);
+
+ stih407_usb2_pico_ctrl(phy_dev);
+
+ ret = regmap_update_bits(phy_dev->regmap,
+ phy_dev->param,
+ STIH407_USB_PICOPHY_PARAM_MASK,
+ STIH407_USB_PICOPHY_PARAM_DEF);
+ if (ret)
+ return ret;
+
+ return reset_control_deassert(phy_dev->rstport);
+}
+
+static int stih407_usb2_exit_port(struct phy *phy)
+{
+ struct stih407_usb2_picophy *phy_dev = phy_get_drvdata(phy);
+
+ /*
+ * Only port reset is asserted, phy global reset is kept untouched
+ * as other ports may still be active. When all ports are in reset
+ * state, assumption is made that power will be cut off on the phy, in
+ * case of suspend for instance. Theoretically, asserting individual
+ * reset (like here) or global reset should be equivalent.
+ */
+ return reset_control_assert(phy_dev->rstport);
+}
+
+static const struct phy_ops stih407_usb2_picophy_data = {
+ .init = stih407_usb2_init_port,
+ .exit = stih407_usb2_exit_port,
+ .owner = THIS_MODULE,
+};
+
+static const struct of_device_id stih407_usb2_picophy_of_match[];
+
+static int stih407_usb2_picophy_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
+ struct stih407_usb2_picophy *phy_dev;
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev->of_node;
+ struct phy_provider *phy_provider;
+ struct phy *phy;
+ struct resource *res;
+
+ phy_dev = devm_kzalloc(dev, sizeof(*phy_dev), GFP_KERNEL);
+ if (!phy_dev)
+ return -ENOMEM;
+
+ match = of_match_device(stih407_usb2_picophy_of_match, dev);
+ if (!match)
+ return -ENODEV;
+
+ phy_dev->dev = dev;
+ dev_set_drvdata(dev, phy_dev);
+
+ phy_dev->rstc = devm_reset_control_get(dev, "global");
+ if (IS_ERR(phy_dev->rstc)) {
+ dev_err(dev, "failed to ctrl picoPHY reset\n");
+ return PTR_ERR(phy_dev->rstc);
+ }
+
+ phy_dev->rstport = devm_reset_control_get(dev, "port");
+ if (IS_ERR(phy_dev->rstport)) {
+ dev_err(dev, "failed to ctrl picoPHY reset\n");
+ return PTR_ERR(phy_dev->rstport);
+ }
+
+ /* Reset port by default: only deassert it in phy init */
+ reset_control_assert(phy_dev->rstport);
+
+ phy_dev->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+ if (IS_ERR(phy_dev->regmap)) {
+ dev_err(dev, "No syscfg phandle specified\n");
+ return PTR_ERR(phy_dev->regmap);
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ctrl");
+ if (!res) {
+ dev_err(dev, "No ctrl reg found\n");
+ return -ENXIO;
+ }
+ phy_dev->ctrl = res->start;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "param");
+ if (!res) {
+ dev_err(dev, "No param reg found\n");
+ return -ENXIO;
+ }
+ phy_dev->param = res->start;
+
+ phy = devm_phy_create(dev, NULL, match->data, NULL);
+ if (IS_ERR(phy)) {
+ dev_err(dev, "failed to create Display Port PHY\n");
+ return PTR_ERR(phy);
+ }
+
+ phy_dev->phy = phy;
+ phy_set_drvdata(phy, phy_dev);
+
+ phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+ if (IS_ERR(phy_provider))
+ return PTR_ERR(phy_provider);
+
+ dev_info(dev, "STiH407 USB Generic picoPHY driver probed!");
+
+ return 0;
+}
+
+static const struct of_device_id stih407_usb2_picophy_of_match[] = {
+ { .compatible = "st,stih407-usb2-phy",
+ .data = &stih407_usb2_picophy_data },
+ { /*sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, stih407_usb2_picophy_of_match);
+
+static struct platform_driver stih407_usb2_picophy_driver = {
+ .probe = stih407_usb2_picophy_probe,
+ .driver = {
+ .name = "stih407-usb-genphy",
+ .of_match_table = stih407_usb2_picophy_of_match,
+ }
+};
+
+module_platform_driver(stih407_usb2_picophy_driver);
+
+MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics Generic picoPHY driver for STiH407");
+MODULE_LICENSE("GPL v2");
--
1.9.1