diff options
Diffstat (limited to 'drivers/usb/phy/phy-rcar-gen2-usb.c')
| -rw-r--r-- | drivers/usb/phy/phy-rcar-gen2-usb.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy-rcar-gen2-usb.c b/drivers/usb/phy/phy-rcar-gen2-usb.c new file mode 100644 index 00000000000..388d89f6b14 --- /dev/null +++ b/drivers/usb/phy/phy-rcar-gen2-usb.c @@ -0,0 +1,248 @@ +/* + * Renesas R-Car Gen2 USB phy driver + * + * Copyright (C) 2013 Renesas Solutions Corp. + * Copyright (C) 2013 Cogent Embedded, Inc. + * + * 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/clk.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_data/usb-rcar-gen2-phy.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> +#include <linux/usb/otg.h> + +struct rcar_gen2_usb_phy_priv { + struct usb_phy phy; + void __iomem *base; + struct clk *clk; + spinlock_t lock; + int usecount; + u32 ugctrl2; +}; + +#define usb_phy_to_priv(p) container_of(p, struct rcar_gen2_usb_phy_priv, phy) + +/* Low Power Status register */ +#define USBHS_LPSTS_REG 0x02 +#define USBHS_LPSTS_SUSPM (1 << 14) + +/* USB General control register */ +#define USBHS_UGCTRL_REG 0x80 +#define USBHS_UGCTRL_CONNECT (1 << 2) +#define USBHS_UGCTRL_PLLRESET (1 << 0) + +/* USB General control register 2 */ +#define USBHS_UGCTRL2_REG 0x84 +#define USBHS_UGCTRL2_USB0_PCI (1 << 4) +#define USBHS_UGCTRL2_USB0_HS (3 << 4) +#define USBHS_UGCTRL2_USB2_PCI (0 << 31) +#define USBHS_UGCTRL2_USB2_SS (1 << 31) + +/* USB General status register */ +#define USBHS_UGSTS_REG 0x88 +#define USBHS_UGSTS_LOCK (3 << 8) + +/* Enable USBHS internal phy */ +static int __rcar_gen2_usbhs_phy_enable(void __iomem *base) +{ + u32 val; + int i; + + /* USBHS PHY power on */ + val = ioread32(base + USBHS_UGCTRL_REG); + val &= ~USBHS_UGCTRL_PLLRESET; + iowrite32(val, base + USBHS_UGCTRL_REG); + + val = ioread16(base + USBHS_LPSTS_REG); + val |= USBHS_LPSTS_SUSPM; + iowrite16(val, base + USBHS_LPSTS_REG); + + for (i = 0; i < 20; i++) { + val = ioread32(base + USBHS_UGSTS_REG); + if ((val & USBHS_UGSTS_LOCK) == USBHS_UGSTS_LOCK) { + val = ioread32(base + USBHS_UGCTRL_REG); + val |= USBHS_UGCTRL_CONNECT; + iowrite32(val, base + USBHS_UGCTRL_REG); + return 0; + } + udelay(1); + } + + /* Timed out waiting for the PLL lock */ + return -ETIMEDOUT; +} + +/* Disable USBHS internal phy */ +static int __rcar_gen2_usbhs_phy_disable(void __iomem *base) +{ + u32 val; + + /* USBHS PHY power off */ + val = ioread32(base + USBHS_UGCTRL_REG); + val &= ~USBHS_UGCTRL_CONNECT; + iowrite32(val, base + USBHS_UGCTRL_REG); + + val = ioread16(base + USBHS_LPSTS_REG); + val &= ~USBHS_LPSTS_SUSPM; + iowrite16(val, base + USBHS_LPSTS_REG); + + val = ioread32(base + USBHS_UGCTRL_REG); + val |= USBHS_UGCTRL_PLLRESET; + iowrite32(val, base + USBHS_UGCTRL_REG); + return 0; +} + +/* Setup USB channels */ +static void __rcar_gen2_usb_phy_init(struct rcar_gen2_usb_phy_priv *priv) +{ + u32 val; + + clk_prepare_enable(priv->clk); + + /* Set USB channels in the USBHS UGCTRL2 register */ + val = ioread32(priv->base + USBHS_UGCTRL2_REG); + val &= ~(USBHS_UGCTRL2_USB0_HS | USBHS_UGCTRL2_USB2_SS); + val |= priv->ugctrl2; + iowrite32(val, priv->base + USBHS_UGCTRL2_REG); +} + +/* Shutdown USB channels */ +static void __rcar_gen2_usb_phy_shutdown(struct rcar_gen2_usb_phy_priv *priv) +{ + __rcar_gen2_usbhs_phy_disable(priv->base); + clk_disable_unprepare(priv->clk); +} + +static int rcar_gen2_usb_phy_set_suspend(struct usb_phy *phy, int suspend) +{ + struct rcar_gen2_usb_phy_priv *priv = usb_phy_to_priv(phy); + unsigned long flags; + int retval; + + spin_lock_irqsave(&priv->lock, flags); + retval = suspend ? __rcar_gen2_usbhs_phy_disable(priv->base) : + __rcar_gen2_usbhs_phy_enable(priv->base); + spin_unlock_irqrestore(&priv->lock, flags); + return retval; +} + +static int rcar_gen2_usb_phy_init(struct usb_phy *phy) +{ + struct rcar_gen2_usb_phy_priv *priv = usb_phy_to_priv(phy); + unsigned long flags; + + spin_lock_irqsave(&priv->lock, flags); + /* + * Enable the clock and setup USB channels + * if it's the first user + */ + if (!priv->usecount++) + __rcar_gen2_usb_phy_init(priv); + spin_unlock_irqrestore(&priv->lock, flags); + return 0; +} + +static void rcar_gen2_usb_phy_shutdown(struct usb_phy *phy) +{ + struct rcar_gen2_usb_phy_priv *priv = usb_phy_to_priv(phy); + unsigned long flags; + + spin_lock_irqsave(&priv->lock, flags); + if (!priv->usecount) { + dev_warn(phy->dev, "Trying to disable phy with 0 usecount\n"); + goto out; + } + + /* Disable everything if it's the last user */ + if (!--priv->usecount) + __rcar_gen2_usb_phy_shutdown(priv); +out: + spin_unlock_irqrestore(&priv->lock, flags); +} + +static int rcar_gen2_usb_phy_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rcar_gen2_phy_platform_data *pdata; + struct rcar_gen2_usb_phy_priv *priv; + struct resource *res; + void __iomem *base; + struct clk *clk; + int retval; + + pdata = dev_get_platdata(dev); + if (!pdata) { + dev_err(dev, "No platform data\n"); + return -EINVAL; + } + + clk = devm_clk_get(dev, "usbhs"); + if (IS_ERR(clk)) { + dev_err(dev, "Can't get the clock\n"); + return PTR_ERR(clk); + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + base = devm_ioremap_resource(dev, res); + if (IS_ERR(base)) + return PTR_ERR(base); + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) { + dev_err(dev, "Memory allocation failed\n"); + return -ENOMEM; + } + + spin_lock_init(&priv->lock); + priv->clk = clk; + priv->base = base; + priv->ugctrl2 = pdata->chan0_pci ? + USBHS_UGCTRL2_USB0_PCI : USBHS_UGCTRL2_USB0_HS; + priv->ugctrl2 |= pdata->chan2_pci ? + USBHS_UGCTRL2_USB2_PCI : USBHS_UGCTRL2_USB2_SS; + priv->phy.dev = dev; + priv->phy.label = dev_name(dev); + priv->phy.init = rcar_gen2_usb_phy_init; + priv->phy.shutdown = rcar_gen2_usb_phy_shutdown; + priv->phy.set_suspend = rcar_gen2_usb_phy_set_suspend; + + retval = usb_add_phy_dev(&priv->phy); + if (retval < 0) { + dev_err(dev, "Failed to add USB phy\n"); + return retval; + } + + platform_set_drvdata(pdev, priv); + + return retval; +} + +static int rcar_gen2_usb_phy_remove(struct platform_device *pdev) +{ + struct rcar_gen2_usb_phy_priv *priv = platform_get_drvdata(pdev); + + usb_remove_phy(&priv->phy); + + return 0; +} + +static struct platform_driver rcar_gen2_usb_phy_driver = { + .driver = { + .name = "usb_phy_rcar_gen2", + }, + .probe = rcar_gen2_usb_phy_probe, + .remove = rcar_gen2_usb_phy_remove, +}; + +module_platform_driver(rcar_gen2_usb_phy_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Renesas R-Car Gen2 USB phy"); +MODULE_AUTHOR("Valentine Barshak <valentine.barshak@cogentembedded.com>"); |