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path: root/drivers/phy/lantiq/phy-lantiq-rcu-usb2.c
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Diffstat (limited to 'drivers/phy/lantiq/phy-lantiq-rcu-usb2.c')
-rw-r--r--drivers/phy/lantiq/phy-lantiq-rcu-usb2.c255
1 files changed, 255 insertions, 0 deletions
diff --git a/drivers/phy/lantiq/phy-lantiq-rcu-usb2.c b/drivers/phy/lantiq/phy-lantiq-rcu-usb2.c
new file mode 100644
index 0000000000..82f1ffc0b0
--- /dev/null
+++ b/drivers/phy/lantiq/phy-lantiq-rcu-usb2.c
@@ -0,0 +1,255 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Lantiq XWAY SoC RCU module based USB 1.1/2.0 PHY driver
+ *
+ * Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ * Copyright (C) 2017 Hauke Mehrtens <hauke@hauke-m.de>
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+/* Transmitter HS Pre-Emphasis Enable */
+#define RCU_CFG1_TX_PEE BIT(0)
+/* Disconnect Threshold */
+#define RCU_CFG1_DIS_THR_MASK 0x00038000
+#define RCU_CFG1_DIS_THR_SHIFT 15
+
+struct ltq_rcu_usb2_bits {
+ u8 hostmode;
+ u8 slave_endianness;
+ u8 host_endianness;
+ bool have_ana_cfg;
+};
+
+struct ltq_rcu_usb2_priv {
+ struct regmap *regmap;
+ unsigned int phy_reg_offset;
+ unsigned int ana_cfg1_reg_offset;
+ const struct ltq_rcu_usb2_bits *reg_bits;
+ struct device *dev;
+ struct phy *phy;
+ struct clk *phy_gate_clk;
+ struct reset_control *ctrl_reset;
+ struct reset_control *phy_reset;
+};
+
+static const struct ltq_rcu_usb2_bits xway_rcu_usb2_reg_bits = {
+ .hostmode = 11,
+ .slave_endianness = 9,
+ .host_endianness = 10,
+ .have_ana_cfg = false,
+};
+
+static const struct ltq_rcu_usb2_bits xrx100_rcu_usb2_reg_bits = {
+ .hostmode = 11,
+ .slave_endianness = 17,
+ .host_endianness = 10,
+ .have_ana_cfg = false,
+};
+
+static const struct ltq_rcu_usb2_bits xrx200_rcu_usb2_reg_bits = {
+ .hostmode = 11,
+ .slave_endianness = 9,
+ .host_endianness = 10,
+ .have_ana_cfg = true,
+};
+
+static const struct of_device_id ltq_rcu_usb2_phy_of_match[] = {
+ {
+ .compatible = "lantiq,ase-usb2-phy",
+ .data = &xway_rcu_usb2_reg_bits,
+ },
+ {
+ .compatible = "lantiq,danube-usb2-phy",
+ .data = &xway_rcu_usb2_reg_bits,
+ },
+ {
+ .compatible = "lantiq,xrx100-usb2-phy",
+ .data = &xrx100_rcu_usb2_reg_bits,
+ },
+ {
+ .compatible = "lantiq,xrx200-usb2-phy",
+ .data = &xrx200_rcu_usb2_reg_bits,
+ },
+ {
+ .compatible = "lantiq,xrx300-usb2-phy",
+ .data = &xrx200_rcu_usb2_reg_bits,
+ },
+ { },
+};
+MODULE_DEVICE_TABLE(of, ltq_rcu_usb2_phy_of_match);
+
+static int ltq_rcu_usb2_phy_init(struct phy *phy)
+{
+ struct ltq_rcu_usb2_priv *priv = phy_get_drvdata(phy);
+
+ if (priv->reg_bits->have_ana_cfg) {
+ regmap_update_bits(priv->regmap, priv->ana_cfg1_reg_offset,
+ RCU_CFG1_TX_PEE, RCU_CFG1_TX_PEE);
+ regmap_update_bits(priv->regmap, priv->ana_cfg1_reg_offset,
+ RCU_CFG1_DIS_THR_MASK, 7 << RCU_CFG1_DIS_THR_SHIFT);
+ }
+
+ /* Configure core to host mode */
+ regmap_update_bits(priv->regmap, priv->phy_reg_offset,
+ BIT(priv->reg_bits->hostmode), 0);
+
+ /* Select DMA endianness (Host-endian: big-endian) */
+ regmap_update_bits(priv->regmap, priv->phy_reg_offset,
+ BIT(priv->reg_bits->slave_endianness), 0);
+ regmap_update_bits(priv->regmap, priv->phy_reg_offset,
+ BIT(priv->reg_bits->host_endianness),
+ BIT(priv->reg_bits->host_endianness));
+
+ return 0;
+}
+
+static int ltq_rcu_usb2_phy_power_on(struct phy *phy)
+{
+ struct ltq_rcu_usb2_priv *priv = phy_get_drvdata(phy);
+ struct device *dev = priv->dev;
+ int ret;
+
+ reset_control_deassert(priv->phy_reset);
+
+ ret = clk_prepare_enable(priv->phy_gate_clk);
+ if (ret) {
+ dev_err(dev, "failed to enable PHY gate\n");
+ return ret;
+ }
+
+ /*
+ * at least the xrx200 usb2 phy requires some extra time to be
+ * operational after enabling the clock
+ */
+ usleep_range(100, 200);
+
+ return ret;
+}
+
+static int ltq_rcu_usb2_phy_power_off(struct phy *phy)
+{
+ struct ltq_rcu_usb2_priv *priv = phy_get_drvdata(phy);
+
+ reset_control_assert(priv->phy_reset);
+
+ clk_disable_unprepare(priv->phy_gate_clk);
+
+ return 0;
+}
+
+static const struct phy_ops ltq_rcu_usb2_phy_ops = {
+ .init = ltq_rcu_usb2_phy_init,
+ .power_on = ltq_rcu_usb2_phy_power_on,
+ .power_off = ltq_rcu_usb2_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static int ltq_rcu_usb2_of_parse(struct ltq_rcu_usb2_priv *priv,
+ struct platform_device *pdev)
+{
+ struct device *dev = priv->dev;
+ const __be32 *offset;
+
+ priv->reg_bits = of_device_get_match_data(dev);
+
+ priv->regmap = syscon_node_to_regmap(dev->of_node->parent);
+ if (IS_ERR(priv->regmap)) {
+ dev_err(dev, "Failed to lookup RCU regmap\n");
+ return PTR_ERR(priv->regmap);
+ }
+
+ offset = of_get_address(dev->of_node, 0, NULL, NULL);
+ if (!offset) {
+ dev_err(dev, "Failed to get RCU PHY reg offset\n");
+ return -ENOENT;
+ }
+ priv->phy_reg_offset = __be32_to_cpu(*offset);
+
+ if (priv->reg_bits->have_ana_cfg) {
+ offset = of_get_address(dev->of_node, 1, NULL, NULL);
+ if (!offset) {
+ dev_err(dev, "Failed to get RCU ANA CFG1 reg offset\n");
+ return -ENOENT;
+ }
+ priv->ana_cfg1_reg_offset = __be32_to_cpu(*offset);
+ }
+
+ priv->phy_gate_clk = devm_clk_get(dev, "phy");
+ if (IS_ERR(priv->phy_gate_clk)) {
+ dev_err(dev, "Unable to get USB phy gate clk\n");
+ return PTR_ERR(priv->phy_gate_clk);
+ }
+
+ priv->ctrl_reset = devm_reset_control_get_shared(dev, "ctrl");
+ if (IS_ERR(priv->ctrl_reset)) {
+ if (PTR_ERR(priv->ctrl_reset) != -EPROBE_DEFER)
+ dev_err(dev, "failed to get 'ctrl' reset\n");
+ return PTR_ERR(priv->ctrl_reset);
+ }
+
+ priv->phy_reset = devm_reset_control_get_optional(dev, "phy");
+
+ return PTR_ERR_OR_ZERO(priv->phy_reset);
+}
+
+static int ltq_rcu_usb2_phy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ltq_rcu_usb2_priv *priv;
+ struct phy_provider *provider;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = dev;
+
+ ret = ltq_rcu_usb2_of_parse(priv, pdev);
+ if (ret)
+ return ret;
+
+ /* Reset USB core through reset controller */
+ reset_control_deassert(priv->ctrl_reset);
+
+ reset_control_assert(priv->phy_reset);
+
+ priv->phy = devm_phy_create(dev, dev->of_node, &ltq_rcu_usb2_phy_ops);
+ if (IS_ERR(priv->phy)) {
+ dev_err(dev, "failed to create PHY\n");
+ return PTR_ERR(priv->phy);
+ }
+
+ phy_set_drvdata(priv->phy, priv);
+
+ provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+ if (IS_ERR(provider))
+ return PTR_ERR(provider);
+
+ dev_set_drvdata(priv->dev, priv);
+ return 0;
+}
+
+static struct platform_driver ltq_rcu_usb2_phy_driver = {
+ .probe = ltq_rcu_usb2_phy_probe,
+ .driver = {
+ .name = "lantiq-rcu-usb2-phy",
+ .of_match_table = ltq_rcu_usb2_phy_of_match,
+ }
+};
+module_platform_driver(ltq_rcu_usb2_phy_driver);
+
+MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
+MODULE_DESCRIPTION("Lantiq XWAY USB2 PHY driver");
+MODULE_LICENSE("GPL v2");