linux/drivers/usb/otg/ulpi.c
Daniel Mack 2d57a95f09 USB OTG: Add generic driver for ULPI OTG transceiver
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@caiaq.de>
Cc: Heikki Krogerus <ext-heikki.krogerus@nokia.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2009-12-11 11:55:16 -08:00

137 lines
4.0 KiB
C

/*
* Generic ULPI USB transceiver support
*
* 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.
*
* 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);