[PATCH 2/5] USB OTG: Add generic driver for ULPI OTG transceiver
Daniel Mack
daniel at caiaq.de
Wed Sep 2 16:47:55 EDT 2009
This adds a minimal generic driver for ULPI connected transceivers,
using the OTG framework functions recently introduced.
The driver got a table to match the ULPI chips, which currently only has
one entry for NXP's ISP 1504 transceiver.
Signed-off-by: Daniel Mack <daniel at caiaq.de>
Cc: Greg Kroah-Hartman <gregkh at suse.de>
Cc: David Brownell <dbrownell at users.sourceforge.net>
Cc: Sascha Hauer <s.hauer at pengutronix.de>
Cc: linux-usb at vger.kernel.org
---
drivers/usb/Makefile | 2 +
drivers/usb/otg/Kconfig | 9 +++
drivers/usb/otg/Makefile | 1 +
drivers/usb/otg/ulpi.c | 136 ++++++++++++++++++++++++++++++++++++++++++++++
include/linux/usb/ulpi.h | 7 +++
5 files changed, 155 insertions(+), 0 deletions(-)
create mode 100644 drivers/usb/otg/ulpi.c
create mode 100644 include/linux/usb/ulpi.h
diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
index 19cb7d5..37797e3 100644
--- a/drivers/usb/Makefile
+++ b/drivers/usb/Makefile
@@ -42,3 +42,5 @@ obj-$(CONFIG_USB) += misc/
obj-$(CONFIG_USB_ATM) += atm/
obj-$(CONFIG_USB_SPEEDTOUCH) += atm/
+
+obj-$(CONFIG_USB_ULPI) += otg/
diff --git a/drivers/usb/otg/Kconfig b/drivers/usb/otg/Kconfig
index aa884d0..de56b3d 100644
--- a/drivers/usb/otg/Kconfig
+++ b/drivers/usb/otg/Kconfig
@@ -41,6 +41,15 @@ config ISP1301_OMAP
This driver can also be built as a module. If so, the module
will be called isp1301_omap.
+config USB_ULPI
+ bool "Generic ULPI Transceiver Driver"
+ depends on ARM
+ help
+ Enable this to support ULPI connected USB OTG transceivers which
+ are likely found on embedded boards.
+
+ The only chip currently supported is NXP's ISP1504
+
config TWL4030_USB
tristate "TWL4030 USB Transceiver Driver"
depends on TWL4030_CORE && REGULATOR_TWL4030
diff --git a/drivers/usb/otg/Makefile b/drivers/usb/otg/Makefile
index 2081678..aeb49a8 100644
--- a/drivers/usb/otg/Makefile
+++ b/drivers/usb/otg/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_USB_GPIO_VBUS) += gpio_vbus.o
obj-$(CONFIG_ISP1301_OMAP) += isp1301_omap.o
obj-$(CONFIG_TWL4030_USB) += twl4030-usb.o
obj-$(CONFIG_NOP_USB_XCEIV) += nop-usb-xceiv.o
+obj-$(CONFIG_USB_ULPI) += ulpi.o
ccflags-$(CONFIG_USB_DEBUG) += -DDEBUG
ccflags-$(CONFIG_USB_GADGET_DEBUG) += -DDEBUG
diff --git a/drivers/usb/otg/ulpi.c b/drivers/usb/otg/ulpi.c
new file mode 100644
index 0000000..8965274
--- /dev/null
+++ b/drivers/usb/otg/ulpi.c
@@ -0,0 +1,136 @@
+/*
+ * Generic ULPI USB transceiver support
+ *
+ * Copyright (C) 2009 Daniel Mack <daniel at caiaq.de>
+ *
+ * Based on sources from
+ *
+ * Sascha Hauer <s.hauer at 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.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/usb.h>
+#include <linux/usb/otg.h>
+#include <linux/usb/ulpi.h>
+
+/* ULPI register addresses */
+#define ULPI_VID_LOW 0x00 /* Vendor ID low */
+#define ULPI_VID_HIGH 0x01 /* Vendor ID high */
+#define ULPI_PID_LOW 0x02 /* Product ID low */
+#define ULPI_PID_HIGH 0x03 /* Product ID high */
+#define ULPI_ITFCTL 0x07 /* Interface Control */
+#define ULPI_OTGCTL 0x0A /* OTG Control */
+
+/* add to above register address to access Set/Clear functions */
+#define ULPI_REG_SET 0x01
+#define ULPI_REG_CLEAR 0x02
+
+/* ULPI OTG Control Register bits */
+#define ID_PULL_UP (1 << 0) /* enable ID Pull Up */
+#define DP_PULL_DOWN (1 << 1) /* enable DP Pull Down */
+#define DM_PULL_DOWN (1 << 2) /* enable DM Pull Down */
+#define DISCHRG_VBUS (1 << 3) /* Discharge Vbus */
+#define CHRG_VBUS (1 << 4) /* Charge Vbus */
+#define DRV_VBUS (1 << 5) /* Drive Vbus */
+#define DRV_VBUS_EXT (1 << 6) /* Drive Vbus external */
+#define USE_EXT_VBUS_IND (1 << 7) /* Use ext. Vbus indicator */
+
+#define ULPI_ID(vendor, product) (((vendor) << 16) | (product))
+
+#define TR_FLAG(flags, a, b) (((flags) & a) ? b : 0)
+
+/* ULPI hardcoded IDs, used for probing */
+static unsigned int ulpi_ids[] = {
+ ULPI_ID(0x04cc, 0x1504), /* NXP ISP1504 */
+};
+
+static int ulpi_set_flags(struct otg_transceiver *otg)
+{
+ unsigned int flags = 0;
+
+ if (otg->flags & USB_OTG_PULLUP_ID)
+ flags |= ID_PULL_UP;
+
+ if (otg->flags & USB_OTG_PULLDOWN_DM)
+ flags |= DM_PULL_DOWN;
+
+ if (otg->flags & USB_OTG_PULLDOWN_DP)
+ flags |= DP_PULL_DOWN;
+
+ if (otg->flags & USB_OTG_EXT_VBUS_INDICATOR)
+ flags |= USE_EXT_VBUS_IND;
+
+ return otg_io_write(otg, flags, ULPI_OTGCTL + ULPI_REG_SET);
+}
+
+static int ulpi_init(struct otg_transceiver *otg)
+{
+ int i, vid, pid;
+
+ vid = (otg_io_read(otg, ULPI_VID_HIGH) << 8) |
+ otg_io_read(otg, ULPI_VID_LOW);
+ pid = (otg_io_read(otg, ULPI_PID_HIGH) << 8) |
+ otg_io_read(otg, ULPI_PID_LOW);
+
+ pr_info("ULPI transceiver vendor/product ID 0x%04x/0x%04x\n", vid, pid);
+
+ for (i = 0; i < ARRAY_SIZE(ulpi_ids); i++)
+ if (ulpi_ids[i] == ULPI_ID(vid, pid))
+ return ulpi_set_flags(otg);
+
+ pr_err("ULPI ID does not match any known transceiver.\n");
+ return -ENODEV;
+}
+
+static int ulpi_set_vbus(struct otg_transceiver *otg, bool on)
+{
+ unsigned int flags = otg_io_read(otg, ULPI_OTGCTL);
+
+ flags &= ~(DRV_VBUS | DRV_VBUS_EXT);
+
+ if (on) {
+ if (otg->flags & USB_OTG_DRV_VBUS)
+ flags |= DRV_VBUS;
+
+ if (otg->flags & USB_OTG_DRV_VBUS_EXT)
+ flags |= DRV_VBUS_EXT;
+ }
+
+ return otg_io_write(otg, flags, ULPI_OTGCTL + ULPI_REG_SET);
+}
+
+struct otg_transceiver *
+otg_ulpi_create(struct otg_io_access_ops *ops,
+ unsigned int flags)
+{
+ struct otg_transceiver *otg;
+
+ otg = kzalloc(sizeof(*otg), GFP_KERNEL);
+ if (!otg)
+ return NULL;
+
+ otg->label = "ULPI";
+ otg->flags = flags;
+ otg->io_ops = ops;
+ otg->init = ulpi_init;
+ otg->set_vbus = ulpi_set_vbus;
+
+ return otg;
+}
+EXPORT_SYMBOL_GPL(otg_ulpi_create);
+
diff --git a/include/linux/usb/ulpi.h b/include/linux/usb/ulpi.h
new file mode 100644
index 0000000..20675c6
--- /dev/null
+++ b/include/linux/usb/ulpi.h
@@ -0,0 +1,7 @@
+#ifndef __LINUX_USB_ULPI_H
+#define __LINUX_USB_ULPI_H
+
+struct otg_transceiver *otg_ulpi_create(struct otg_io_access_ops *ops,
+ unsigned int flags);
+
+#endif /* __LINUX_USB_ULPI_H */
--
1.6.3.3
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