diff options
Diffstat (limited to 'drivers/usb/dwc3/ulpi.c')
-rw-r--r-- | drivers/usb/dwc3/ulpi.c | 91 |
1 files changed, 91 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/ulpi.c b/drivers/usb/dwc3/ulpi.c new file mode 100644 index 0000000..ec004c6 --- /dev/null +++ b/drivers/usb/dwc3/ulpi.c @@ -0,0 +1,91 @@ +/** + * ulpi.c - DesignWare USB3 Controller's ULPI PHY interface + * + * Copyright (C) 2015 Intel Corporation + * + * Author: Heikki Krogerus <heikki.krogerus@linux.intel.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/ulpi/regs.h> + +#include "core.h" +#include "io.h" + +#define DWC3_ULPI_ADDR(a) \ + ((a >= ULPI_EXT_VENDOR_SPECIFIC) ? \ + DWC3_GUSB2PHYACC_ADDR(ULPI_ACCESS_EXTENDED) | \ + DWC3_GUSB2PHYACC_EXTEND_ADDR(a) : DWC3_GUSB2PHYACC_ADDR(a)) + +static int dwc3_ulpi_busyloop(struct dwc3 *dwc) +{ + unsigned count = 1000; + u32 reg; + + while (count--) { + reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYACC(0)); + if (!(reg & DWC3_GUSB2PHYACC_BUSY)) + return 0; + cpu_relax(); + } + + return -ETIMEDOUT; +} + +static int dwc3_ulpi_read(struct ulpi_ops *ops, u8 addr) +{ + struct dwc3 *dwc = dev_get_drvdata(ops->dev); + u32 reg; + int ret; + + reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr); + dwc3_writel(dwc->regs, DWC3_GUSB2PHYACC(0), reg); + + ret = dwc3_ulpi_busyloop(dwc); + if (ret) + return ret; + + reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYACC(0)); + + return DWC3_GUSB2PHYACC_DATA(reg); +} + +static int dwc3_ulpi_write(struct ulpi_ops *ops, u8 addr, u8 val) +{ + struct dwc3 *dwc = dev_get_drvdata(ops->dev); + u32 reg; + + reg = DWC3_GUSB2PHYACC_NEWREGREQ | DWC3_ULPI_ADDR(addr); + reg |= DWC3_GUSB2PHYACC_WRITE | val; + dwc3_writel(dwc->regs, DWC3_GUSB2PHYACC(0), reg); + + return dwc3_ulpi_busyloop(dwc); +} + +static struct ulpi_ops dwc3_ulpi_ops = { + .read = dwc3_ulpi_read, + .write = dwc3_ulpi_write, +}; + +int dwc3_ulpi_init(struct dwc3 *dwc) +{ + /* Register the interface */ + dwc->ulpi = ulpi_register_interface(dwc->dev, &dwc3_ulpi_ops); + if (IS_ERR(dwc->ulpi)) { + dev_err(dwc->dev, "failed to register ULPI interface"); + return PTR_ERR(dwc->ulpi); + } + + return 0; +} + +void dwc3_ulpi_exit(struct dwc3 *dwc) +{ + if (dwc->ulpi) { + ulpi_unregister_interface(dwc->ulpi); + dwc->ulpi = NULL; + } +} |