linux/drivers/usb/chipidea/ulpi.c
Stephen Boyd 7bb7e9b1a4 usb: chipidea: Add support for ULPI PHY bus
Some phys for the chipidea controller are controlled via the ULPI
viewport. Add support for the ULPI bus so that these sorts of
phys can be probed and read/written automatically without having
to duplicate the viewport logic in each phy driver.

Acked-by: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
2017-01-20 11:25:14 +08:00

114 lines
2.6 KiB
C

/*
* Copyright (c) 2016 Linaro Ltd.
*
* 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 <linux/device.h>
#include <linux/usb/chipidea.h>
#include <linux/ulpi/interface.h>
#include "ci.h"
#define ULPI_WAKEUP BIT(31)
#define ULPI_RUN BIT(30)
#define ULPI_WRITE BIT(29)
#define ULPI_SYNC_STATE BIT(27)
#define ULPI_ADDR(n) ((n) << 16)
#define ULPI_DATA(n) (n)
static int ci_ulpi_wait(struct ci_hdrc *ci, u32 mask)
{
unsigned long usec = 10000;
while (usec--) {
if (!hw_read(ci, OP_ULPI_VIEWPORT, mask))
return 0;
udelay(1);
}
return -ETIMEDOUT;
}
static int ci_ulpi_read(struct device *dev, u8 addr)
{
struct ci_hdrc *ci = dev_get_drvdata(dev);
int ret;
hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_WRITE | ULPI_WAKEUP);
ret = ci_ulpi_wait(ci, ULPI_WAKEUP);
if (ret)
return ret;
hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_RUN | ULPI_ADDR(addr));
ret = ci_ulpi_wait(ci, ULPI_RUN);
if (ret)
return ret;
return hw_read(ci, OP_ULPI_VIEWPORT, GENMASK(15, 8)) >> 8;
}
static int ci_ulpi_write(struct device *dev, u8 addr, u8 val)
{
struct ci_hdrc *ci = dev_get_drvdata(dev);
int ret;
hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff, ULPI_WRITE | ULPI_WAKEUP);
ret = ci_ulpi_wait(ci, ULPI_WAKEUP);
if (ret)
return ret;
hw_write(ci, OP_ULPI_VIEWPORT, 0xffffffff,
ULPI_RUN | ULPI_WRITE | ULPI_ADDR(addr) | val);
return ci_ulpi_wait(ci, ULPI_RUN);
}
int ci_ulpi_init(struct ci_hdrc *ci)
{
if (ci->platdata->phy_mode != USBPHY_INTERFACE_MODE_ULPI)
return 0;
/*
* Set PORTSC correctly so we can read/write ULPI registers for
* identification purposes
*/
hw_phymode_configure(ci);
ci->ulpi_ops.read = ci_ulpi_read;
ci->ulpi_ops.write = ci_ulpi_write;
ci->ulpi = ulpi_register_interface(ci->dev, &ci->ulpi_ops);
if (IS_ERR(ci->ulpi))
dev_err(ci->dev, "failed to register ULPI interface");
return PTR_ERR_OR_ZERO(ci->ulpi);
}
void ci_ulpi_exit(struct ci_hdrc *ci)
{
if (ci->ulpi) {
ulpi_unregister_interface(ci->ulpi);
ci->ulpi = NULL;
}
}
int ci_ulpi_resume(struct ci_hdrc *ci)
{
int cnt = 100000;
while (cnt-- > 0) {
if (hw_read(ci, OP_ULPI_VIEWPORT, ULPI_SYNC_STATE))
return 0;
udelay(1);
}
return -ETIMEDOUT;
}