// SPDX-License-Identifier: GPL-2.0 /* * cdns3-ti.c - TI specific Glue layer for Cadence USB Controller * * Copyright (C) 2019 Texas Instruments Incorporated - https://www.ti.com */ #include <linux/bits.h> #include <linux/clk.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/interrupt.h> #include <linux/platform_device.h> #include <linux/dma-mapping.h> #include <linux/io.h> #include <linux/of_platform.h> #include <linux/pm_runtime.h> #include <linux/property.h> /* USB Wrapper register offsets */ #define USBSS_PID 0x0 #define USBSS_W1 0x4 #define USBSS_STATIC_CONFIG 0x8 #define USBSS_PHY_TEST 0xc #define USBSS_DEBUG_CTRL 0x10 #define USBSS_DEBUG_INFO 0x14 #define USBSS_DEBUG_LINK_STATE 0x18 #define USBSS_DEVICE_CTRL 0x1c /* Wrapper 1 register bits */ #define USBSS_W1_PWRUP_RST BIT(0) #define USBSS_W1_OVERCURRENT_SEL BIT(8) #define USBSS_W1_MODESTRAP_SEL BIT(9) #define USBSS_W1_OVERCURRENT BIT(16) #define USBSS_W1_MODESTRAP_MASK GENMASK(18, 17) #define USBSS_W1_MODESTRAP_SHIFT 17 #define USBSS_W1_USB2_ONLY BIT(19) /* Static config register bits */ #define USBSS1_STATIC_PLL_REF_SEL_MASK GENMASK(8, 5) #define USBSS1_STATIC_PLL_REF_SEL_SHIFT 5 #define USBSS1_STATIC_LOOPBACK_MODE_MASK GENMASK(4, 3) #define USBSS1_STATIC_LOOPBACK_MODE_SHIFT 3 #define USBSS1_STATIC_VBUS_SEL_MASK GENMASK(2, 1) #define USBSS1_STATIC_VBUS_SEL_SHIFT 1 #define USBSS1_STATIC_LANE_REVERSE BIT(0) /* Modestrap modes */ enum modestrap_mode { USBSS_MODESTRAP_MODE_NONE, USBSS_MODESTRAP_MODE_HOST, USBSS_MODESTRAP_MODE_PERIPHERAL}; struct cdns_ti { struct device *dev; void __iomem *usbss; unsigned usb2_only:1; unsigned vbus_divider:1; struct clk *usb2_refclk; struct clk *lpm_clk; }; static const int cdns_ti_rate_table[] = { /* in KHZ */ 9600, 10000, 12000, 19200, 20000, 24000, 25000, 26000, 38400, 40000, 58000, 50000, 52000, }; static inline u32 cdns_ti_readl(struct cdns_ti *data, u32 offset) { return readl(data->usbss + offset); } static inline void cdns_ti_writel(struct cdns_ti *data, u32 offset, u32 value) { writel(value, data->usbss + offset); } static int cdns_ti_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *node = pdev->dev.of_node; struct cdns_ti *data; int error; u32 reg; int rate_code, i; unsigned long rate; data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; platform_set_drvdata(pdev, data); data->dev = dev; data->usbss = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(data->usbss)) { dev_err(dev, "can't map IOMEM resource\n"); return PTR_ERR(data->usbss); } data->usb2_refclk = devm_clk_get(dev, "ref"); if (IS_ERR(data->usb2_refclk)) { dev_err(dev, "can't get usb2_refclk\n"); return PTR_ERR(data->usb2_refclk); } data->lpm_clk = devm_clk_get(dev, "lpm"); if (IS_ERR(data->lpm_clk)) { dev_err(dev, "can't get lpm_clk\n"); return PTR_ERR(data->lpm_clk); } rate = clk_get_rate(data->usb2_refclk); rate /= 1000; /* To KHz */ for (i = 0; i < ARRAY_SIZE(cdns_ti_rate_table); i++) { if (cdns_ti_rate_table[i] == rate) break; } if (i == ARRAY_SIZE(cdns_ti_rate_table)) { dev_err(dev, "unsupported usb2_refclk rate: %lu KHz\n", rate); return -EINVAL; } rate_code = i; pm_runtime_enable(dev); error = pm_runtime_get_sync(dev); if (error < 0) { dev_err(dev, "pm_runtime_get_sync failed: %d\n", error); goto err; } /* assert RESET */ reg = cdns_ti_readl(data, USBSS_W1); reg &= ~USBSS_W1_PWRUP_RST; cdns_ti_writel(data, USBSS_W1, reg); /* set static config */ reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG); reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK; reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT; reg &= ~USBSS1_STATIC_VBUS_SEL_MASK; data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider"); if (data->vbus_divider) reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT; cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg); reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG); /* set USB2_ONLY mode if requested */ reg = cdns_ti_readl(data, USBSS_W1); data->usb2_only = device_property_read_bool(dev, "ti,usb2-only"); if (data->usb2_only) reg |= USBSS_W1_USB2_ONLY; /* set default modestrap */ reg |= USBSS_W1_MODESTRAP_SEL; reg &= ~USBSS_W1_MODESTRAP_MASK; reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT; cdns_ti_writel(data, USBSS_W1, reg); /* de-assert RESET */ reg |= USBSS_W1_PWRUP_RST; cdns_ti_writel(data, USBSS_W1, reg); error = of_platform_populate(node, NULL, NULL, dev); if (error) { dev_err(dev, "failed to create children: %d\n", error); goto err; } return 0; err: pm_runtime_put_sync(data->dev); pm_runtime_disable(data->dev); return error; } static int cdns_ti_remove_core(struct device *dev, void *c) { struct platform_device *pdev = to_platform_device(dev); platform_device_unregister(pdev); return 0; } static void cdns_ti_remove(struct platform_device *pdev) { struct device *dev = &pdev->dev; device_for_each_child(dev, NULL, cdns_ti_remove_core); pm_runtime_put_sync(dev); pm_runtime_disable(dev); platform_set_drvdata(pdev, NULL); } static const struct of_device_id cdns_ti_of_match[] = { { .compatible = "ti,j721e-usb", }, { .compatible = "ti,am64-usb", }, {}, }; MODULE_DEVICE_TABLE(of, cdns_ti_of_match); static struct platform_driver cdns_ti_driver = { .probe = cdns_ti_probe, .remove_new = cdns_ti_remove, .driver = { .name = "cdns3-ti", .of_match_table = cdns_ti_of_match, }, }; module_platform_driver(cdns_ti_driver); MODULE_ALIAS("platform:cdns3-ti"); MODULE_AUTHOR("Roger Quadros <rogerq@ti.com>"); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Cadence USB3 TI Glue Layer");