/* * 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> #define PHYPARAM_REG 1 #define PHYCTRL_REG 2 /* 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 int stih407_usb2_picophy_probe(struct platform_device *pdev) { 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; int ret; phy_dev = devm_kzalloc(dev, sizeof(*phy_dev), GFP_KERNEL); if (!phy_dev) return -ENOMEM; phy_dev->dev = dev; dev_set_drvdata(dev, phy_dev); phy_dev->rstc = devm_reset_control_get_shared(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_exclusive(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); } ret = of_property_read_u32_index(np, "st,syscfg", PHYPARAM_REG, &phy_dev->param); if (ret) { dev_err(dev, "can't get phyparam offset (%d)\n", ret); return ret; } ret = of_property_read_u32_index(np, "st,syscfg", PHYCTRL_REG, &phy_dev->ctrl); if (ret) { dev_err(dev, "can't get phyctrl offset (%d)\n", ret); return ret; } phy = devm_phy_create(dev, NULL, &stih407_usb2_picophy_data); 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" }, { /*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");