diff options
Diffstat (limited to 'drivers/usb/chipidea/ulpi.c')
-rw-r--r-- | drivers/usb/chipidea/ulpi.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/drivers/usb/chipidea/ulpi.c b/drivers/usb/chipidea/ulpi.c new file mode 100644 index 000000000000..1219583dc1b2 --- /dev/null +++ b/drivers/usb/chipidea/ulpi.c @@ -0,0 +1,113 @@ +/* + * 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; +} |