USB: Add generic ULPI layer and a viewport

Add partial ULPI specification implementation that should be enough to
interface the ULPI PHYs in the boot loader context.
Add a viewport implementation for Chipidea/ARC based controllers.

Signed-off-by: Jana Rapava <fermata7@gmail.com>
Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Cc: Remy Bohmer <linux@bohmer.net>
Cc: Stefano Babic <sbabic@denx.de>
Cc: Wolfgang Grandegger <wg@denx.de>
Cc: Simon Glass <sjg@chromium.org>

3 files changed, 389 insertions, 0 deletions

diff --git a/drivers/usb/ulpi/Makefile b/drivers/usb/ulpi/Makefile
new file mode 100644
index 0000000..d43b229
--- /dev/null
+++ b/drivers/usb/ulpi/Makefile
@@ -0,0 +1,44 @@
+#
+# Copyright (C) 2011 Jana Rapava <fermata7@gmail.com>
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc.
+#
+
+include $(TOPDIR)/config.mk
+
+LIB	:= $(obj)libusb_ulpi.o
+
+COBJS-$(CONFIG_USB_ULPI)		+= ulpi.o
+COBJS-$(CONFIG_USB_ULPI_VIEWPORT)	+= ulpi-viewport.o
+
+COBJS	:= $(COBJS-y)
+SRCS	:= $(COBJS:.o=.c)
+OBJS	:= $(addprefix $(obj),$(COBJS))
+
+all:	$(LIB)
+
+$(LIB):	$(obj).depend $(OBJS)
+	$(call cmd_link_o_target, $(OBJS))
+
+#########################################################################
+
+# defines $(obj).depend target
+include $(SRCTREE)/rules.mk
+
+sinclude $(obj).depend
+
+#########################################################################
diff --git a/drivers/usb/ulpi/ulpi-viewport.c b/drivers/usb/ulpi/ulpi-viewport.c
new file mode 100644
index 0000000..fa2e004
--- /dev/null
+++ b/drivers/usb/ulpi/ulpi-viewport.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright (C) 2011 Jana Rapava <fermata7@gmail.com>
+ * Copyright (C) 2011 CompuLab, Ltd. <www.compulab.co.il>
+ *
+ * Authors: Jana Rapava <fermata7@gmail.com>
+ *	    Igor Grinberg <grinberg@compulab.co.il>
+ *
+ * Based on:
+ * linux/drivers/usb/otg/ulpi_viewport.c
+ *
+ * Original Copyright follow:
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <usb/ulpi.h>
+
+/* ULPI viewport control bits */
+#define ULPI_SS		(1 << 27)
+#define ULPI_RWCTRL	(1 << 29)
+#define ULPI_RWRUN	(1 << 30)
+#define ULPI_WU		(1 << 31)
+
+/*
+ * Wait for the ULPI request to complete
+ *
+ * @ulpi_viewport	- the address of the viewport
+ * @mask		- expected value to wait for
+ *
+ * returns 0 on mask match, ULPI_ERROR on time out.
+ */
+static int ulpi_wait(u32 ulpi_viewport, u32 mask)
+{
+	int timeout = CONFIG_USB_ULPI_TIMEOUT;
+
+	/* Wait for the bits in mask to become zero. */
+	while (--timeout) {
+		if ((readl(ulpi_viewport) & mask) == 0)
+			return 0;
+
+		udelay(1);
+	}
+
+	return ULPI_ERROR;
+}
+
+/*
+ * Wake the ULPI PHY up for communication
+ *
+ * returns 0 on success.
+ */
+static int ulpi_wakeup(u32 ulpi_viewport)
+{
+	int err;
+
+	if (readl(ulpi_viewport) & ULPI_SS)
+		return 0; /* already awake */
+
+	writel(ULPI_WU, ulpi_viewport);
+
+	err = ulpi_wait(ulpi_viewport, ULPI_WU);
+	if (err)
+		printf("ULPI wakeup timed out\n");
+
+	return err;
+}
+
+/*
+ * Issue a ULPI read/write request
+ *
+ * @value - the ULPI request
+ */
+static int ulpi_request(u32 ulpi_viewport, u32 value)
+{
+	int err;
+
+	err = ulpi_wakeup(ulpi_viewport);
+	if (err)
+		return err;
+
+	writel(value, ulpi_viewport);
+
+	err = ulpi_wait(ulpi_viewport, ULPI_RWRUN);
+	if (err)
+		printf("ULPI request timed out\n");
+
+	return err;
+}
+
+u32 ulpi_write(u32 ulpi_viewport, u8 *reg, u32 value)
+{
+	u32 val = ULPI_RWRUN | ULPI_RWCTRL | ((u32)reg << 16) | (value & 0xff);
+
+	return ulpi_request(ulpi_viewport, val);
+}
+
+u32 ulpi_read(u32 ulpi_viewport, u8 *reg)
+{
+	u32 err;
+	u32 val = ULPI_RWRUN | ((u32)reg << 16);
+
+	err = ulpi_request(ulpi_viewport, val);
+	if (err)
+		return err;
+
+	return (readl(ulpi_viewport) >> 8) & 0xff;
+}
diff --git a/drivers/usb/ulpi/ulpi.c b/drivers/usb/ulpi/ulpi.c
new file mode 100644
index 0000000..805e29d
--- /dev/null
+++ b/drivers/usb/ulpi/ulpi.c
@@ -0,0 +1,227 @@
+/*
+ * Copyright (C) 2011 Jana Rapava <fermata7@gmail.com>
+ * Copyright (C) 2011 CompuLab, Ltd. <www.compulab.co.il>
+ *
+ * Authors: Jana Rapava <fermata7@gmail.com>
+ *	    Igor Grinberg <grinberg@compulab.co.il>
+ *
+ * Based on:
+ * linux/drivers/usb/otg/ulpi.c
+ * Generic ULPI USB transceiver support
+ *
+ * Original Copyright follow:
+ * Copyright (C) 2009 Daniel Mack <daniel@caiaq.de>
+ *
+ * Based on sources from
+ *
+ *   Sascha Hauer <s.hauer@pengutronix.de>
+ *   Freescale Semiconductors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <common.h>
+#include <exports.h>
+#include <usb/ulpi.h>
+
+#define ULPI_ID_REGS_COUNT	4
+#define ULPI_TEST_VALUE		0x55	/* 0x55 == 0b01010101 */
+
+static struct ulpi_regs *ulpi = (struct ulpi_regs *)0;
+
+static int ulpi_integrity_check(u32 ulpi_viewport)
+{
+	u32 err, val, tval = ULPI_TEST_VALUE;
+	int i;
+
+	/* Use the 'special' test value to check all bits */
+	for (i = 0; i < 2; i++, tval <<= 1) {
+		err = ulpi_write(ulpi_viewport, &ulpi->scratch, tval);
+		if (err)
+			return err;
+
+		val = ulpi_read(ulpi_viewport, &ulpi->scratch);
+		if (val != tval) {
+			printf("ULPI integrity check failed\n");
+			return val;
+		}
+	}
+
+	return 0;
+}
+
+int ulpi_init(u32 ulpi_viewport)
+{
+	u32 val, id = 0;
+	u8 *reg = &ulpi->product_id_high;
+	int i;
+
+	/* Assemble ID from four ULPI ID registers (8 bits each). */
+	for (i = 0; i < ULPI_ID_REGS_COUNT; i++) {
+		val = ulpi_read(ulpi_viewport, reg - i);
+		if (val == ULPI_ERROR)
+			return val;
+
+		id = (id << 8) | val;
+	}
+
+	/* Split ID into vendor and product ID. */
+	debug("ULPI transceiver ID 0x%04x:0x%04x\n", id >> 16, id & 0xffff);
+
+	return ulpi_integrity_check(ulpi_viewport);
+}
+
+int ulpi_select_transceiver(u32 ulpi_viewport, u8 speed)
+{
+	u8 tspeed = ULPI_FC_FULL_SPEED;
+	u32 val;
+
+	switch (speed) {
+	case ULPI_FC_HIGH_SPEED:
+	case ULPI_FC_FULL_SPEED:
+	case ULPI_FC_LOW_SPEED:
+	case ULPI_FC_FS4LS:
+		tspeed = speed;
+		break;
+	default:
+		printf("ULPI: %s: wrong transceiver speed specified, "
+			"falling back to full speed\n", __func__);
+	}
+
+	val = ulpi_read(ulpi_viewport, &ulpi->function_ctrl);
+	if (val == ULPI_ERROR)
+		return val;
+
+	/* clear the previous speed setting */
+	val = (val & ~ULPI_FC_XCVRSEL_MASK) | tspeed;
+
+	return ulpi_write(ulpi_viewport, &ulpi->function_ctrl, val);
+}
+
+int ulpi_set_vbus(u32 ulpi_viewport, int on, int ext_power, int ext_ind)
+{
+	u32 flags = ULPI_OTG_DRVVBUS;
+	u8 *reg = on ? &ulpi->otg_ctrl_set : &ulpi->otg_ctrl_clear;
+
+	if (ext_power)
+		flags |= ULPI_OTG_DRVVBUS_EXT;
+	if (ext_ind)
+		flags |= ULPI_OTG_EXTVBUSIND;
+
+	return ulpi_write(ulpi_viewport, reg, flags);
+}
+
+int ulpi_set_pd(u32 ulpi_viewport, int enable)
+{
+	u32 val = ULPI_OTG_DP_PULLDOWN | ULPI_OTG_DM_PULLDOWN;
+	u8 *reg = enable ? &ulpi->otg_ctrl_set : &ulpi->otg_ctrl_clear;
+
+	return ulpi_write(ulpi_viewport, reg, val);
+}
+
+int ulpi_opmode_sel(u32 ulpi_viewport, u8 opmode)
+{
+	u8 topmode = ULPI_FC_OPMODE_NORMAL;
+	u32 val;
+
+	switch (opmode) {
+	case ULPI_FC_OPMODE_NORMAL:
+	case ULPI_FC_OPMODE_NONDRIVING:
+	case ULPI_FC_OPMODE_DISABLE_NRZI:
+	case ULPI_FC_OPMODE_NOSYNC_NOEOP:
+		topmode = opmode;
+		break;
+	default:
+		printf("ULPI: %s: wrong OpMode specified, "
+			"falling back to OpMode Normal\n", __func__);
+	}
+
+	val = ulpi_read(ulpi_viewport, &ulpi->function_ctrl);
+	if (val == ULPI_ERROR)
+		return val;
+
+	/* clear the previous opmode setting */
+	val = (val & ~ULPI_FC_OPMODE_MASK) | topmode;
+
+	return ulpi_write(ulpi_viewport, &ulpi->function_ctrl, val);
+}
+
+int ulpi_serial_mode_enable(u32 ulpi_viewport, u8 smode)
+{
+	switch (smode) {
+	case ULPI_IFACE_6_PIN_SERIAL_MODE:
+	case ULPI_IFACE_3_PIN_SERIAL_MODE:
+		break;
+	default:
+		printf("ULPI: %s: unrecognized Serial Mode specified\n",
+			__func__);
+		return ULPI_ERROR;
+	}
+
+	return ulpi_write(ulpi_viewport, &ulpi->iface_ctrl_set, smode);
+}
+
+int ulpi_suspend(u32 ulpi_viewport)
+{
+	u32 err;
+
+	err = ulpi_write(ulpi_viewport, &ulpi->function_ctrl_clear,
+			ULPI_FC_SUSPENDM);
+	if (err)
+		printf("ULPI: %s: failed writing the suspend bit\n", __func__);
+
+	return err;
+}
+
+/*
+ * Wait for ULPI PHY reset to complete.
+ * Actual wait for reset must be done in a view port specific way,
+ * because it involves checking the DIR line.
+ */
+static int __ulpi_reset_wait(u32 ulpi_viewport)
+{
+	u32 val;
+	int timeout = CONFIG_USB_ULPI_TIMEOUT;
+
+	/* Wait for the RESET bit to become zero */
+	while (--timeout) {
+		/*
+		 * This function is generic and suppose to work
+		 * with any viewport, so we cheat here and don't check
+		 * for the error of ulpi_read(), if there is one, then
+		 * there will be a timeout.
+		 */
+		val = ulpi_read(ulpi_viewport, &ulpi->function_ctrl);
+		if (!(val & ULPI_FC_RESET))
+			return 0;
+
+		udelay(1);
+	}
+
+	printf("ULPI: %s: reset timed out\n", __func__);
+
+	return ULPI_ERROR;
+}
+int ulpi_reset_wait(u32) __attribute__((weak, alias("__ulpi_reset_wait")));
+
+int ulpi_reset(u32 ulpi_viewport)
+{
+	u32 err;
+
+	err = ulpi_write(ulpi_viewport,
+			&ulpi->function_ctrl_set, ULPI_FC_RESET);
+	if (err) {
+		printf("ULPI: %s: failed writing reset bit\n", __func__);
+		return err;
+	}
+
+	return ulpi_reset_wait(ulpi_viewport);
+}