1 files changed, 533 insertions, 2 deletions

diff --git a/drivers/usb/host/ehci-tegra.c b/drivers/usb/host/ehci-tegra.c
index a1c43f8..b77806f 100644
--- a/drivers/usb/host/ehci-tegra.c
+++ b/drivers/usb/host/ehci-tegra.c
@@ -1,5 +1,7 @@
 /*
+ * Copyright (c) 2011 The Chromium OS Authors.
  * Copyright (c) 2009-2012 NVIDIA Corporation
+ * Copyright (c) 2013 Lucas Stach
  *
  * See file CREDITS for list of people who contributed to this
  * project.
@@ -21,12 +23,128 @@
  */
 
 #include <common.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <asm-generic/gpio.h>
+#include <asm/arch/clock.h>
+#include <asm/arch-tegra/usb.h>
 #include <usb.h>
+#include <usb/ulpi.h>
+#include <libfdt.h>
+#include <fdtdec.h>
 
 #include "ehci.h"
 
-#include <asm/errno.h>
-#include <asm/arch/usb.h>
+#ifdef CONFIG_USB_ULPI
+	#ifndef CONFIG_USB_ULPI_VIEWPORT
+	#error	"To use CONFIG_USB_ULPI on Tegra Boards you have to also \
+		define CONFIG_USB_ULPI_VIEWPORT"
+	#endif
+#endif
+
+enum {
+	USB_PORTS_MAX	= 3,		/* Maximum ports we allow */
+};
+
+/* Parameters we need for USB */
+enum {
+	PARAM_DIVN,                     /* PLL FEEDBACK DIVIDer */
+	PARAM_DIVM,                     /* PLL INPUT DIVIDER */
+	PARAM_DIVP,                     /* POST DIVIDER (2^N) */
+	PARAM_CPCON,                    /* BASE PLLC CHARGE Pump setup ctrl */
+	PARAM_LFCON,                    /* BASE PLLC LOOP FILter setup ctrl */
+	PARAM_ENABLE_DELAY_COUNT,       /* PLL-U Enable Delay Count */
+	PARAM_STABLE_COUNT,             /* PLL-U STABLE count */
+	PARAM_ACTIVE_DELAY_COUNT,       /* PLL-U Active delay count */
+	PARAM_XTAL_FREQ_COUNT,          /* PLL-U XTAL frequency count */
+	PARAM_DEBOUNCE_A_TIME,          /* 10MS DELAY for BIAS_DEBOUNCE_A */
+	PARAM_BIAS_TIME,                /* 20US DELAY AFter bias cell op */
+
+	PARAM_COUNT
+};
+
+/* Possible port types (dual role mode) */
+enum dr_mode {
+	DR_MODE_NONE = 0,
+	DR_MODE_HOST,		/* supports host operation */
+	DR_MODE_DEVICE,		/* supports device operation */
+	DR_MODE_OTG,		/* supports both */
+};
+
+/* Information about a USB port */
+struct fdt_usb {
+	struct usb_ctlr *reg;	/* address of registers in physical memory */
+	unsigned utmi:1;	/* 1 if port has external tranceiver, else 0 */
+	unsigned ulpi:1;	/* 1 if port has external ULPI transceiver */
+	unsigned enabled:1;	/* 1 to enable, 0 to disable */
+	unsigned has_legacy_mode:1; /* 1 if this port has legacy mode */
+	unsigned initialized:1; /* has this port already been initialized? */
+	enum dr_mode dr_mode;	/* dual role mode */
+	enum periph_id periph_id;/* peripheral id */
+	struct fdt_gpio_state vbus_gpio;	/* GPIO for vbus enable */
+	struct fdt_gpio_state phy_reset_gpio; /* GPIO to reset ULPI phy */
+};
+
+static struct fdt_usb port[USB_PORTS_MAX];	/* List of valid USB ports */
+static unsigned port_count;			/* Number of available ports */
+
+/*
+ * This table has USB timing parameters for each Oscillator frequency we
+ * support. There are four sets of values:
+ *
+ * 1. PLLU configuration information (reference clock is osc/clk_m and
+ * PLLU-FOs are fixed at 12MHz/60MHz/480MHz).
+ *
+ *  Reference frequency     13.0MHz      19.2MHz      12.0MHz      26.0MHz
+ *  ----------------------------------------------------------------------
+ *      DIVN                960 (0x3c0)  200 (0c8)    960 (3c0h)   960 (3c0)
+ *      DIVM                13 (0d)      4 (04)       12 (0c)      26 (1a)
+ * Filter frequency (MHz)   1            4.8          6            2
+ * CPCON                    1100b        0011b        1100b        1100b
+ * LFCON0                   0            0            0            0
+ *
+ * 2. PLL CONFIGURATION & PARAMETERS for different clock generators:
+ *
+ * Reference frequency     13.0MHz         19.2MHz         12.0MHz     26.0MHz
+ * ---------------------------------------------------------------------------
+ * PLLU_ENABLE_DLY_COUNT   02 (0x02)       03 (03)         02 (02)     04 (04)
+ * PLLU_STABLE_COUNT       51 (33)         75 (4B)         47 (2F)    102 (66)
+ * PLL_ACTIVE_DLY_COUNT    05 (05)         06 (06)         04 (04)     09 (09)
+ * XTAL_FREQ_COUNT        127 (7F)        187 (BB)        118 (76)    254 (FE)
+ *
+ * 3. Debounce values IdDig, Avalid, Bvalid, VbusValid, VbusWakeUp, and
+ * SessEnd. Each of these signals have their own debouncer and for each of
+ * those one out of two debouncing times can be chosen (BIAS_DEBOUNCE_A or
+ * BIAS_DEBOUNCE_B).
+ *
+ * The values of DEBOUNCE_A and DEBOUNCE_B are calculated as follows:
+ *    0xffff -> No debouncing at all
+ *    <n> ms = <n> *1000 / (1/19.2MHz) / 4
+ *
+ * So to program a 1 ms debounce for BIAS_DEBOUNCE_A, we have:
+ * BIAS_DEBOUNCE_A[15:0] = 1000 * 19.2 / 4  = 4800 = 0x12c0
+ *
+ * We need to use only DebounceA for BOOTROM. We don't need the DebounceB
+ * values, so we can keep those to default.
+ *
+ * 4. The 20 microsecond delay after bias cell operation.
+ */
+static const unsigned usb_pll[CLOCK_OSC_FREQ_COUNT][PARAM_COUNT] = {
+	/* DivN, DivM, DivP, CPCON, LFCON, Delays             Debounce, Bias */
+	{ 0x3C0, 0x0D, 0x00, 0xC,   0,  0x02, 0x33, 0x05, 0x7F, 0x7EF4, 5 },
+	{ 0x0C8, 0x04, 0x00, 0x3,   0,  0x03, 0x4B, 0x06, 0xBB, 0xBB80, 7 },
+	{ 0x3C0, 0x0C, 0x00, 0xC,   0,  0x02, 0x2F, 0x04, 0x76, 0x7530, 5 },
+	{ 0x3C0, 0x1A, 0x00, 0xC,   0,  0x04, 0x66, 0x09, 0xFE, 0xFDE8, 9 }
+};
+
+/* UTMIP Idle Wait Delay */
+static const u8 utmip_idle_wait_delay = 17;
+
+/* UTMIP Elastic limit */
+static const u8 utmip_elastic_limit = 16;
+
+/* UTMIP High Speed Sync Start Delay */
+static const u8 utmip_hs_sync_start_delay = 9;
 
 /*
  * A known hardware issue where Connect Status Change bit of PORTSC register
@@ -45,6 +163,419 @@ void ehci_powerup_fixup(uint32_t *status_reg, uint32_t *reg)
 		*reg |= EHCI_PS_CSC;
 }
 
+/* Put the port into host mode */
+static void set_host_mode(struct fdt_usb *config)
+{
+	/*
+	 * If we are an OTG port, check if remote host is driving VBus and
+	 * bail out in this case.
+	 */
+	if (config->dr_mode == DR_MODE_OTG &&
+		(readl(&config->reg->phy_vbus_sensors) & VBUS_VLD_STS))
+		return;
+
+	/*
+	 * If not driving, we set the GPIO to enable VBUS. We assume
+	 * that the pinmux is set up correctly for this.
+	 */
+	if (fdt_gpio_isvalid(&config->vbus_gpio)) {
+		fdtdec_setup_gpio(&config->vbus_gpio);
+		gpio_direction_output(config->vbus_gpio.gpio,
+			(config->vbus_gpio.flags & FDT_GPIO_ACTIVE_LOW) ?
+				 0 : 1);
+		debug("set_host_mode: GPIO %d %s\n", config->vbus_gpio.gpio,
+			(config->vbus_gpio.flags & FDT_GPIO_ACTIVE_LOW) ?
+				"low" : "high");
+	}
+}
+
+void usbf_reset_controller(struct fdt_usb *config, struct usb_ctlr *usbctlr)
+{
+	/* Reset the USB controller with 2us delay */
+	reset_periph(config->periph_id, 2);
+
+	/*
+	 * Set USB1_NO_LEGACY_MODE to 1, Registers are accessible under
+	 * base address
+	 */
+	if (config->has_legacy_mode)
+		setbits_le32(&usbctlr->usb1_legacy_ctrl, USB1_NO_LEGACY_MODE);
+
+	/* Put UTMIP1/3 in reset */
+	setbits_le32(&usbctlr->susp_ctrl, UTMIP_RESET);
+
+	/* Enable the UTMIP PHY */
+	if (config->utmi)
+		setbits_le32(&usbctlr->susp_ctrl, UTMIP_PHY_ENB);
+}
+
+/* set up the UTMI USB controller with the parameters provided */
+static int init_utmi_usb_controller(struct fdt_usb *config)
+{
+	u32 val;
+	int loop_count;
+	const unsigned *timing;
+	struct usb_ctlr *usbctlr = config->reg;
+
+	clock_enable(config->periph_id);
+
+	/* Reset the usb controller */
+	usbf_reset_controller(config, usbctlr);
+
+	/* Stop crystal clock by setting UTMIP_PHY_XTAL_CLOCKEN low */
+	clrbits_le32(&usbctlr->utmip_misc_cfg1, UTMIP_PHY_XTAL_CLOCKEN);
+
+	/* Follow the crystal clock disable by >100ns delay */
+	udelay(1);
+
+	/*
+	 * To Use the A Session Valid for cable detection logic, VBUS_WAKEUP
+	 * mux must be switched to actually use a_sess_vld threshold.
+	 */
+	if (fdt_gpio_isvalid(&config->vbus_gpio)) {
+		clrsetbits_le32(&usbctlr->usb1_legacy_ctrl,
+			VBUS_SENSE_CTL_MASK,
+			VBUS_SENSE_CTL_A_SESS_VLD << VBUS_SENSE_CTL_SHIFT);
+	}
+
+	/*
+	 * PLL Delay CONFIGURATION settings. The following parameters control
+	 * the bring up of the plls.
+	 */
+	timing = usb_pll[clock_get_osc_freq()];
+
+	val = readl(&usbctlr->utmip_misc_cfg1);
+	clrsetbits_le32(&val, UTMIP_PLLU_STABLE_COUNT_MASK,
+		timing[PARAM_STABLE_COUNT] << UTMIP_PLLU_STABLE_COUNT_SHIFT);
+	clrsetbits_le32(&val, UTMIP_PLL_ACTIVE_DLY_COUNT_MASK,
+		timing[PARAM_ACTIVE_DELAY_COUNT] <<
+			UTMIP_PLL_ACTIVE_DLY_COUNT_SHIFT);
+	writel(val, &usbctlr->utmip_misc_cfg1);
+
+	/* Set PLL enable delay count and crystal frequency count */
+	val = readl(&usbctlr->utmip_pll_cfg1);
+	clrsetbits_le32(&val, UTMIP_PLLU_ENABLE_DLY_COUNT_MASK,
+		timing[PARAM_ENABLE_DELAY_COUNT] <<
+			UTMIP_PLLU_ENABLE_DLY_COUNT_SHIFT);
+	clrsetbits_le32(&val, UTMIP_XTAL_FREQ_COUNT_MASK,
+		timing[PARAM_XTAL_FREQ_COUNT] <<
+			UTMIP_XTAL_FREQ_COUNT_SHIFT);
+	writel(val, &usbctlr->utmip_pll_cfg1);
+
+	/* Setting the tracking length time */
+	clrsetbits_le32(&usbctlr->utmip_bias_cfg1,
+		UTMIP_BIAS_PDTRK_COUNT_MASK,
+		timing[PARAM_BIAS_TIME] << UTMIP_BIAS_PDTRK_COUNT_SHIFT);
+
+	/* Program debounce time for VBUS to become valid */
+	clrsetbits_le32(&usbctlr->utmip_debounce_cfg0,
+		UTMIP_DEBOUNCE_CFG0_MASK,
+		timing[PARAM_DEBOUNCE_A_TIME] << UTMIP_DEBOUNCE_CFG0_SHIFT);
+
+	setbits_le32(&usbctlr->utmip_tx_cfg0, UTMIP_FS_PREAMBLE_J);
+
+	/* Disable battery charge enabling bit */
+	setbits_le32(&usbctlr->utmip_bat_chrg_cfg0, UTMIP_PD_CHRG);
+
+	clrbits_le32(&usbctlr->utmip_xcvr_cfg0, UTMIP_XCVR_LSBIAS_SE);
+	setbits_le32(&usbctlr->utmip_spare_cfg0, FUSE_SETUP_SEL);
+
+	/*
+	 * Configure the UTMIP_IDLE_WAIT and UTMIP_ELASTIC_LIMIT
+	 * Setting these fields, together with default values of the
+	 * other fields, results in programming the registers below as
+	 * follows:
+	 *         UTMIP_HSRX_CFG0 = 0x9168c000
+	 *         UTMIP_HSRX_CFG1 = 0x13
+	 */
+
+	/* Set PLL enable delay count and Crystal frequency count */
+	val = readl(&usbctlr->utmip_hsrx_cfg0);
+	clrsetbits_le32(&val, UTMIP_IDLE_WAIT_MASK,
+		utmip_idle_wait_delay << UTMIP_IDLE_WAIT_SHIFT);
+	clrsetbits_le32(&val, UTMIP_ELASTIC_LIMIT_MASK,
+		utmip_elastic_limit << UTMIP_ELASTIC_LIMIT_SHIFT);
+	writel(val, &usbctlr->utmip_hsrx_cfg0);
+
+	/* Configure the UTMIP_HS_SYNC_START_DLY */
+	clrsetbits_le32(&usbctlr->utmip_hsrx_cfg1,
+		UTMIP_HS_SYNC_START_DLY_MASK,
+		utmip_hs_sync_start_delay << UTMIP_HS_SYNC_START_DLY_SHIFT);
+
+	/* Preceed the crystal clock disable by >100ns delay. */
+	udelay(1);
+
+	/* Resuscitate crystal clock by setting UTMIP_PHY_XTAL_CLOCKEN */
+	setbits_le32(&usbctlr->utmip_misc_cfg1, UTMIP_PHY_XTAL_CLOCKEN);
+
+	/* Finished the per-controller init. */
+
+	/* De-assert UTMIP_RESET to bring out of reset. */
+	clrbits_le32(&usbctlr->susp_ctrl, UTMIP_RESET);
+
+	/* Wait for the phy clock to become valid in 100 ms */
+	for (loop_count = 100000; loop_count != 0; loop_count--) {
+		if (readl(&usbctlr->susp_ctrl) & USB_PHY_CLK_VALID)
+			break;
+		udelay(1);
+	}
+	if (!loop_count)
+		return -1;
+
+	/* Disable ICUSB FS/LS transceiver */
+	clrbits_le32(&usbctlr->icusb_ctrl, IC_ENB1);
+
+	/* Select UTMI parallel interface */
+	clrsetbits_le32(&usbctlr->port_sc1, PTS_MASK,
+			PTS_UTMI << PTS_SHIFT);
+	clrbits_le32(&usbctlr->port_sc1, STS);
+
+	/* Deassert power down state */
+	clrbits_le32(&usbctlr->utmip_xcvr_cfg0, UTMIP_FORCE_PD_POWERDOWN |
+		UTMIP_FORCE_PD2_POWERDOWN | UTMIP_FORCE_PDZI_POWERDOWN);
+	clrbits_le32(&usbctlr->utmip_xcvr_cfg1, UTMIP_FORCE_PDDISC_POWERDOWN |
+		UTMIP_FORCE_PDCHRP_POWERDOWN | UTMIP_FORCE_PDDR_POWERDOWN);
+
+	return 0;
+}
+
+#ifdef CONFIG_USB_ULPI
+/* if board file does not set a ULPI reference frequency we default to 24MHz */
+#ifndef CONFIG_ULPI_REF_CLK
+#define CONFIG_ULPI_REF_CLK 24000000
+#endif
+
+/* set up the ULPI USB controller with the parameters provided */
+static int init_ulpi_usb_controller(struct fdt_usb *config)
+{
+	u32 val;
+	int loop_count;
+	struct ulpi_viewport ulpi_vp;
+	struct usb_ctlr *usbctlr = config->reg;
+
+	/* set up ULPI reference clock on pllp_out4 */
+	clock_enable(PERIPH_ID_DEV2_OUT);
+	clock_set_pllout(CLOCK_ID_PERIPH, PLL_OUT4, CONFIG_ULPI_REF_CLK);
+
+	/* reset ULPI phy */
+	if (fdt_gpio_isvalid(&config->phy_reset_gpio)) {
+		fdtdec_setup_gpio(&config->phy_reset_gpio);
+		gpio_direction_output(config->phy_reset_gpio.gpio, 0);
+		mdelay(5);
+		gpio_set_value(config->phy_reset_gpio.gpio, 1);
+	}
+
+	/* Reset the usb controller */
+	clock_enable(config->periph_id);
+	usbf_reset_controller(config, usbctlr);
+
+	/* enable pinmux bypass */
+	setbits_le32(&usbctlr->ulpi_timing_ctrl_0,
+			ULPI_CLKOUT_PINMUX_BYP | ULPI_OUTPUT_PINMUX_BYP);
+
+	/* Select ULPI parallel interface */
+	clrsetbits_le32(&usbctlr->port_sc1, PTS_MASK, PTS_ULPI << PTS_SHIFT);
+
+	/* enable ULPI transceiver */
+	setbits_le32(&usbctlr->susp_ctrl, ULPI_PHY_ENB);
+
+	/* configure ULPI transceiver timings */
+	val = 0;
+	writel(val, &usbctlr->ulpi_timing_ctrl_1);
+
+	val |= ULPI_DATA_TRIMMER_SEL(4);
+	val |= ULPI_STPDIRNXT_TRIMMER_SEL(4);
+	val |= ULPI_DIR_TRIMMER_SEL(4);
+	writel(val, &usbctlr->ulpi_timing_ctrl_1);
+	udelay(10);
+
+	val |= ULPI_DATA_TRIMMER_LOAD;
+	val |= ULPI_STPDIRNXT_TRIMMER_LOAD;
+	val |= ULPI_DIR_TRIMMER_LOAD;
+	writel(val, &usbctlr->ulpi_timing_ctrl_1);
+
+	/* set up phy for host operation with external vbus supply */
+	ulpi_vp.port_num = 0;
+	ulpi_vp.viewport_addr = (u32)&usbctlr->ulpi_viewport;
+
+	if (ulpi_init(&ulpi_vp)) {
+		printf("Tegra ULPI viewport init failed\n");
+		return -1;
+	}
+
+	ulpi_set_vbus(&ulpi_vp, 1, 1);
+	ulpi_set_vbus_indicator(&ulpi_vp, 1, 1, 0);
+
+	/* enable wakeup events */
+	setbits_le32(&usbctlr->port_sc1, WKCN | WKDS | WKOC);
+
+	/* Enable and wait for the phy clock to become valid in 100 ms */
+	setbits_le32(&usbctlr->susp_ctrl, USB_SUSP_CLR);
+	for (loop_count = 100000; loop_count != 0; loop_count--) {
+		if (readl(&usbctlr->susp_ctrl) & USB_PHY_CLK_VALID)
+			break;
+		udelay(1);
+	}
+	if (!loop_count)
+		return -1;
+	clrbits_le32(&usbctlr->susp_ctrl, USB_SUSP_CLR);
+
+	return 0;
+}
+#else
+static int init_ulpi_usb_controller(struct fdt_usb *config)
+{
+	printf("No code to set up ULPI controller, please enable"
+			"CONFIG_USB_ULPI and CONFIG_USB_ULPI_VIEWPORT");
+	return -1;
+}
+#endif
+
+static void config_clock(const u32 timing[])
+{
+	clock_start_pll(CLOCK_ID_USB,
+		timing[PARAM_DIVM], timing[PARAM_DIVN], timing[PARAM_DIVP],
+		timing[PARAM_CPCON], timing[PARAM_LFCON]);
+}
+
+int tegrausb_start_port(int portnum, u32 *hccr, u32 *hcor)
+{
+	struct fdt_usb *config;
+	struct usb_ctlr *usbctlr;
+
+	if (portnum >= port_count)
+		return -1;
+
+	config = &port[portnum];
+
+	/* skip init, if the port is already initialized */
+	if (config->initialized)
+		goto success;
+
+	if (config->utmi && init_utmi_usb_controller(config)) {
+		printf("tegrausb: Cannot init port %d\n", portnum);
+		return -1;
+	}
+
+	if (config->ulpi && init_ulpi_usb_controller(config)) {
+		printf("tegrausb: Cannot init port %d\n", portnum);
+		return -1;
+	}
+
+	set_host_mode(config);
+
+	config->initialized = 1;
+
+success:
+	usbctlr = config->reg;
+	*hccr = (u32)&usbctlr->cap_length;
+	*hcor = (u32)&usbctlr->usb_cmd;
+	return 0;
+}
+
+int tegrausb_stop_port(int portnum)
+{
+	struct usb_ctlr *usbctlr;
+
+	usbctlr = port[portnum].reg;
+
+	/* Stop controller */
+	writel(0, &usbctlr->usb_cmd);
+	udelay(1000);
+
+	/* Initiate controller reset */
+	writel(2, &usbctlr->usb_cmd);
+	udelay(1000);
+
+	port[portnum].initialized = 0;
+
+	return 0;
+}
+
+int fdt_decode_usb(const void *blob, int node, struct fdt_usb *config)
+{
+	const char *phy, *mode;
+
+	config->reg = (struct usb_ctlr *)fdtdec_get_addr(blob, node, "reg");
+	mode = fdt_getprop(blob, node, "dr_mode", NULL);
+	if (mode) {
+		if (0 == strcmp(mode, "host"))
+			config->dr_mode = DR_MODE_HOST;
+		else if (0 == strcmp(mode, "peripheral"))
+			config->dr_mode = DR_MODE_DEVICE;
+		else if (0 == strcmp(mode, "otg"))
+			config->dr_mode = DR_MODE_OTG;
+		else {
+			debug("%s: Cannot decode dr_mode '%s'\n", __func__,
+			      mode);
+			return -FDT_ERR_NOTFOUND;
+		}
+	} else {
+		config->dr_mode = DR_MODE_HOST;
+	}
+
+	phy = fdt_getprop(blob, node, "phy_type", NULL);
+	config->utmi = phy && 0 == strcmp("utmi", phy);
+	config->ulpi = phy && 0 == strcmp("ulpi", phy);
+	config->enabled = fdtdec_get_is_enabled(blob, node);
+	config->has_legacy_mode = fdtdec_get_bool(blob, node,
+						  "nvidia,has-legacy-mode");
+	config->periph_id = clock_decode_periph_id(blob, node);
+	if (config->periph_id == PERIPH_ID_NONE) {
+		debug("%s: Missing/invalid peripheral ID\n", __func__);
+		return -FDT_ERR_NOTFOUND;
+	}
+	fdtdec_decode_gpio(blob, node, "nvidia,vbus-gpio", &config->vbus_gpio);
+	fdtdec_decode_gpio(blob, node, "nvidia,phy-reset-gpio",
+			&config->phy_reset_gpio);
+	debug("enabled=%d, legacy_mode=%d, utmi=%d, ulpi=%d, periph_id=%d, "
+		"vbus=%d, phy_reset=%d, dr_mode=%d\n",
+		config->enabled, config->has_legacy_mode, config->utmi,
+		config->ulpi, config->periph_id, config->vbus_gpio.gpio,
+		config->phy_reset_gpio.gpio, config->dr_mode);
+
+	return 0;
+}
+
+int board_usb_init(const void *blob)
+{
+	struct fdt_usb config;
+	enum clock_osc_freq freq;
+	int node_list[USB_PORTS_MAX];
+	int node, count, i;
+
+	/* Set up the USB clocks correctly based on our oscillator frequency */
+	freq = clock_get_osc_freq();
+	config_clock(usb_pll[freq]);
+
+	/* count may return <0 on error */
+	count = fdtdec_find_aliases_for_id(blob, "usb",
+			COMPAT_NVIDIA_TEGRA20_USB, node_list, USB_PORTS_MAX);
+	for (i = 0; i < count; i++) {
+		if (port_count == USB_PORTS_MAX) {
+			printf("tegrausb: Cannot register more than %d ports\n",
+				USB_PORTS_MAX);
+			return -1;
+		}
+
+		debug("USB %d: ", i);
+		node = node_list[i];
+		if (!node)
+			continue;
+		if (fdt_decode_usb(blob, node, &config)) {
+			debug("Cannot decode USB node %s\n",
+			      fdt_get_name(blob, node, NULL));
+			return -1;
+		}
+		config.initialized = 0;
+
+		/* add new USB port to the list of available ports */
+		port[port_count++] = config;
+	}
+
+	return 0;
+}
+
 /*
  * Create the appropriate control structures to manage
  * a new EHCI host controller.