diff options
Diffstat (limited to 'drivers/phy/lantiq/phy-lantiq-rcu-usb2.c')
| -rw-r--r-- | drivers/phy/lantiq/phy-lantiq-rcu-usb2.c | 255 |
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, <q_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"); |