1 files changed, 721 insertions, 0 deletions

diff --git a/drivers/usb/otg/twl4030-usb.c b/drivers/usb/otg/twl4030-usb.c
new file mode 100644
index 000000000000..416e4410be02
--- /dev/null
+++ b/drivers/usb/otg/twl4030-usb.c
@@ -0,0 +1,721 @@
+/*
+ * twl4030_usb - TWL4030 USB transceiver, talking to OMAP OTG controller
+ *
+ * Copyright (C) 2004-2007 Texas Instruments
+ * Copyright (C) 2008 Nokia Corporation
+ * Contact: Felipe Balbi <felipe.balbi@nokia.com>
+ *
+ * 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.
+ *
+ * Current status:
+ *      - HS USB ULPI mode works.
+ *      - 3-pin mode support may be added in future.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/usb/otg.h>
+#include <linux/i2c/twl4030.h>
+
+
+/* Register defines */
+
+#define VENDOR_ID_LO                    0x00
+#define VENDOR_ID_HI                    0x01
+#define PRODUCT_ID_LO                   0x02
+#define PRODUCT_ID_HI                   0x03
+
+#define FUNC_CTRL                       0x04
+#define FUNC_CTRL_SET                   0x05
+#define FUNC_CTRL_CLR                   0x06
+#define FUNC_CTRL_SUSPENDM              (1 << 6)
+#define FUNC_CTRL_RESET                 (1 << 5)
+#define FUNC_CTRL_OPMODE_MASK           (3 << 3) /* bits 3 and 4 */
+#define FUNC_CTRL_OPMODE_NORMAL         (0 << 3)
+#define FUNC_CTRL_OPMODE_NONDRIVING     (1 << 3)
+#define FUNC_CTRL_OPMODE_DISABLE_BIT_NRZI       (2 << 3)
+#define FUNC_CTRL_TERMSELECT            (1 << 2)
+#define FUNC_CTRL_XCVRSELECT_MASK       (3 << 0) /* bits 0 and 1 */
+#define FUNC_CTRL_XCVRSELECT_HS         (0 << 0)
+#define FUNC_CTRL_XCVRSELECT_FS         (1 << 0)
+#define FUNC_CTRL_XCVRSELECT_LS         (2 << 0)
+#define FUNC_CTRL_XCVRSELECT_FS4LS      (3 << 0)
+
+#define IFC_CTRL                        0x07
+#define IFC_CTRL_SET                    0x08
+#define IFC_CTRL_CLR                    0x09
+#define IFC_CTRL_INTERFACE_PROTECT_DISABLE      (1 << 7)
+#define IFC_CTRL_AUTORESUME             (1 << 4)
+#define IFC_CTRL_CLOCKSUSPENDM          (1 << 3)
+#define IFC_CTRL_CARKITMODE             (1 << 2)
+#define IFC_CTRL_FSLSSERIALMODE_3PIN    (1 << 1)
+
+#define TWL4030_OTG_CTRL                0x0A
+#define TWL4030_OTG_CTRL_SET            0x0B
+#define TWL4030_OTG_CTRL_CLR            0x0C
+#define TWL4030_OTG_CTRL_DRVVBUS        (1 << 5)
+#define TWL4030_OTG_CTRL_CHRGVBUS       (1 << 4)
+#define TWL4030_OTG_CTRL_DISCHRGVBUS    (1 << 3)
+#define TWL4030_OTG_CTRL_DMPULLDOWN     (1 << 2)
+#define TWL4030_OTG_CTRL_DPPULLDOWN     (1 << 1)
+#define TWL4030_OTG_CTRL_IDPULLUP       (1 << 0)
+
+#define USB_INT_EN_RISE                 0x0D
+#define USB_INT_EN_RISE_SET             0x0E
+#define USB_INT_EN_RISE_CLR             0x0F
+#define USB_INT_EN_FALL                 0x10
+#define USB_INT_EN_FALL_SET             0x11
+#define USB_INT_EN_FALL_CLR             0x12
+#define USB_INT_STS                     0x13
+#define USB_INT_LATCH                   0x14
+#define USB_INT_IDGND                   (1 << 4)
+#define USB_INT_SESSEND                 (1 << 3)
+#define USB_INT_SESSVALID               (1 << 2)
+#define USB_INT_VBUSVALID               (1 << 1)
+#define USB_INT_HOSTDISCONNECT          (1 << 0)
+
+#define CARKIT_CTRL                     0x19
+#define CARKIT_CTRL_SET                 0x1A
+#define CARKIT_CTRL_CLR                 0x1B
+#define CARKIT_CTRL_MICEN               (1 << 6)
+#define CARKIT_CTRL_SPKRIGHTEN          (1 << 5)
+#define CARKIT_CTRL_SPKLEFTEN           (1 << 4)
+#define CARKIT_CTRL_RXDEN               (1 << 3)
+#define CARKIT_CTRL_TXDEN               (1 << 2)
+#define CARKIT_CTRL_IDGNDDRV            (1 << 1)
+#define CARKIT_CTRL_CARKITPWR           (1 << 0)
+#define CARKIT_PLS_CTRL                 0x22
+#define CARKIT_PLS_CTRL_SET             0x23
+#define CARKIT_PLS_CTRL_CLR             0x24
+#define CARKIT_PLS_CTRL_SPKRRIGHT_BIASEN        (1 << 3)
+#define CARKIT_PLS_CTRL_SPKRLEFT_BIASEN (1 << 2)
+#define CARKIT_PLS_CTRL_RXPLSEN         (1 << 1)
+#define CARKIT_PLS_CTRL_TXPLSEN         (1 << 0)
+
+#define MCPC_CTRL                       0x30
+#define MCPC_CTRL_SET                   0x31
+#define MCPC_CTRL_CLR                   0x32
+#define MCPC_CTRL_RTSOL                 (1 << 7)
+#define MCPC_CTRL_EXTSWR                (1 << 6)
+#define MCPC_CTRL_EXTSWC                (1 << 5)
+#define MCPC_CTRL_VOICESW               (1 << 4)
+#define MCPC_CTRL_OUT64K                (1 << 3)
+#define MCPC_CTRL_RTSCTSSW              (1 << 2)
+#define MCPC_CTRL_HS_UART               (1 << 0)
+
+#define MCPC_IO_CTRL                    0x33
+#define MCPC_IO_CTRL_SET                0x34
+#define MCPC_IO_CTRL_CLR                0x35
+#define MCPC_IO_CTRL_MICBIASEN          (1 << 5)
+#define MCPC_IO_CTRL_CTS_NPU            (1 << 4)
+#define MCPC_IO_CTRL_RXD_PU             (1 << 3)
+#define MCPC_IO_CTRL_TXDTYP             (1 << 2)
+#define MCPC_IO_CTRL_CTSTYP             (1 << 1)
+#define MCPC_IO_CTRL_RTSTYP             (1 << 0)
+
+#define MCPC_CTRL2                      0x36
+#define MCPC_CTRL2_SET                  0x37
+#define MCPC_CTRL2_CLR                  0x38
+#define MCPC_CTRL2_MCPC_CK_EN           (1 << 0)
+
+#define OTHER_FUNC_CTRL                 0x80
+#define OTHER_FUNC_CTRL_SET             0x81
+#define OTHER_FUNC_CTRL_CLR             0x82
+#define OTHER_FUNC_CTRL_BDIS_ACON_EN    (1 << 4)
+#define OTHER_FUNC_CTRL_FIVEWIRE_MODE   (1 << 2)
+
+#define OTHER_IFC_CTRL                  0x83
+#define OTHER_IFC_CTRL_SET              0x84
+#define OTHER_IFC_CTRL_CLR              0x85
+#define OTHER_IFC_CTRL_OE_INT_EN        (1 << 6)
+#define OTHER_IFC_CTRL_CEA2011_MODE     (1 << 5)
+#define OTHER_IFC_CTRL_FSLSSERIALMODE_4PIN      (1 << 4)
+#define OTHER_IFC_CTRL_HIZ_ULPI_60MHZ_OUT       (1 << 3)
+#define OTHER_IFC_CTRL_HIZ_ULPI         (1 << 2)
+#define OTHER_IFC_CTRL_ALT_INT_REROUTE  (1 << 0)
+
+#define OTHER_INT_EN_RISE               0x86
+#define OTHER_INT_EN_RISE_SET           0x87
+#define OTHER_INT_EN_RISE_CLR           0x88
+#define OTHER_INT_EN_FALL               0x89
+#define OTHER_INT_EN_FALL_SET           0x8A
+#define OTHER_INT_EN_FALL_CLR           0x8B
+#define OTHER_INT_STS                   0x8C
+#define OTHER_INT_LATCH                 0x8D
+#define OTHER_INT_VB_SESS_VLD           (1 << 7)
+#define OTHER_INT_DM_HI                 (1 << 6) /* not valid for "latch" reg */
+#define OTHER_INT_DP_HI                 (1 << 5) /* not valid for "latch" reg */
+#define OTHER_INT_BDIS_ACON             (1 << 3) /* not valid for "fall" regs */
+#define OTHER_INT_MANU                  (1 << 1)
+#define OTHER_INT_ABNORMAL_STRESS       (1 << 0)
+
+#define ID_STATUS                       0x96
+#define ID_RES_FLOAT                    (1 << 4)
+#define ID_RES_440K                     (1 << 3)
+#define ID_RES_200K                     (1 << 2)
+#define ID_RES_102K                     (1 << 1)
+#define ID_RES_GND                      (1 << 0)
+
+#define POWER_CTRL                      0xAC
+#define POWER_CTRL_SET                  0xAD
+#define POWER_CTRL_CLR                  0xAE
+#define POWER_CTRL_OTG_ENAB             (1 << 5)
+
+#define OTHER_IFC_CTRL2                 0xAF
+#define OTHER_IFC_CTRL2_SET             0xB0
+#define OTHER_IFC_CTRL2_CLR             0xB1
+#define OTHER_IFC_CTRL2_ULPI_STP_LOW    (1 << 4)
+#define OTHER_IFC_CTRL2_ULPI_TXEN_POL   (1 << 3)
+#define OTHER_IFC_CTRL2_ULPI_4PIN_2430  (1 << 2)
+#define OTHER_IFC_CTRL2_USB_INT_OUTSEL_MASK     (3 << 0) /* bits 0 and 1 */
+#define OTHER_IFC_CTRL2_USB_INT_OUTSEL_INT1N    (0 << 0)
+#define OTHER_IFC_CTRL2_USB_INT_OUTSEL_INT2N    (1 << 0)
+
+#define REG_CTRL_EN                     0xB2
+#define REG_CTRL_EN_SET                 0xB3
+#define REG_CTRL_EN_CLR                 0xB4
+#define REG_CTRL_ERROR                  0xB5
+#define ULPI_I2C_CONFLICT_INTEN         (1 << 0)
+
+#define OTHER_FUNC_CTRL2                0xB8
+#define OTHER_FUNC_CTRL2_SET            0xB9
+#define OTHER_FUNC_CTRL2_CLR            0xBA
+#define OTHER_FUNC_CTRL2_VBAT_TIMER_EN  (1 << 0)
+
+/* following registers do not have separate _clr and _set registers */
+#define VBUS_DEBOUNCE                   0xC0
+#define ID_DEBOUNCE                     0xC1
+#define VBAT_TIMER                      0xD3
+#define PHY_PWR_CTRL                    0xFD
+#define PHY_PWR_PHYPWD                  (1 << 0)
+#define PHY_CLK_CTRL                    0xFE
+#define PHY_CLK_CTRL_CLOCKGATING_EN     (1 << 2)
+#define PHY_CLK_CTRL_CLK32K_EN          (1 << 1)
+#define REQ_PHY_DPLL_CLK                (1 << 0)
+#define PHY_CLK_CTRL_STS                0xFF
+#define PHY_DPLL_CLK                    (1 << 0)
+
+/* In module TWL4030_MODULE_PM_MASTER */
+#define PROTECT_KEY                     0x0E
+
+/* In module TWL4030_MODULE_PM_RECEIVER */
+#define VUSB_DEDICATED1                 0x7D
+#define VUSB_DEDICATED2                 0x7E
+#define VUSB1V5_DEV_GRP                 0x71
+#define VUSB1V5_TYPE                    0x72
+#define VUSB1V5_REMAP                   0x73
+#define VUSB1V8_DEV_GRP                 0x74
+#define VUSB1V8_TYPE                    0x75
+#define VUSB1V8_REMAP                   0x76
+#define VUSB3V1_DEV_GRP                 0x77
+#define VUSB3V1_TYPE                    0x78
+#define VUSB3V1_REMAP                   0x79
+
+/* In module TWL4030_MODULE_INTBR */
+#define PMBR1                           0x0D
+#define GPIO_USB_4PIN_ULPI_2430C        (3 << 0)
+
+
+
+enum linkstat {
+        USB_LINK_UNKNOWN = 0,
+        USB_LINK_NONE,
+        USB_LINK_VBUS,
+        USB_LINK_ID,
+};
+
+struct twl4030_usb {
+        struct otg_transceiver  otg;
+        struct device           *dev;
+
+        /* for vbus reporting with irqs disabled */
+        spinlock_t              lock;
+
+        /* pin configuration */
+        enum twl4030_usb_mode   usb_mode;
+
+        int                     irq;
+        u8                      linkstat;
+        u8                      asleep;
+        bool                    irq_enabled;
+};
+
+/* internal define on top of container_of */
+#define xceiv_to_twl(x)         container_of((x), struct twl4030_usb, otg);
+
+/*-------------------------------------------------------------------------*/
+
+static int twl4030_i2c_write_u8_verify(struct twl4030_usb *twl,
+                u8 module, u8 data, u8 address)
+{
+        u8 check;
+
+        if ((twl4030_i2c_write_u8(module, data, address) >= 0) &&
+            (twl4030_i2c_read_u8(module, &check, address) >= 0) &&
+                                                (check == data))
+                return 0;
+        dev_dbg(twl->dev, "Write%d[%d,0x%x] wrote %02x but read %02x\n",
+                        1, module, address, check, data);
+
+        /* Failed once: Try again */
+        if ((twl4030_i2c_write_u8(module, data, address) >= 0) &&
+            (twl4030_i2c_read_u8(module, &check, address) >= 0) &&
+                                                (check == data))
+                return 0;
+        dev_dbg(twl->dev, "Write%d[%d,0x%x] wrote %02x but read %02x\n",
+                        2, module, address, check, data);
+
+        /* Failed again: Return error */
+        return -EBUSY;
+}
+
+#define twl4030_usb_write_verify(twl, address, data)    \
+        twl4030_i2c_write_u8_verify(twl, TWL4030_MODULE_USB, (data), (address))
+
+static inline int twl4030_usb_write(struct twl4030_usb *twl,
+                u8 address, u8 data)
+{
+        int ret = 0;
+
+        ret = twl4030_i2c_write_u8(TWL4030_MODULE_USB, data, address);
+        if (ret < 0)
+                dev_dbg(twl->dev,
+                        "TWL4030:USB:Write[0x%x] Error %d\n", address, ret);
+        return ret;
+}
+
+static inline int twl4030_readb(struct twl4030_usb *twl, u8 module, u8 address)
+{
+        u8 data;
+        int ret = 0;
+
+        ret = twl4030_i2c_read_u8(module, &data, address);
+        if (ret >= 0)
+                ret = data;
+        else
+                dev_dbg(twl->dev,
+                        "TWL4030:readb[0x%x,0x%x] Error %d\n",
+                                        module, address, ret);
+
+        return ret;
+}
+
+static inline int twl4030_usb_read(struct twl4030_usb *twl, u8 address)
+{
+        return twl4030_readb(twl, TWL4030_MODULE_USB, address);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline int
+twl4030_usb_set_bits(struct twl4030_usb *twl, u8 reg, u8 bits)
+{
+        return twl4030_usb_write(twl, reg + 1, bits);
+}
+
+static inline int
+twl4030_usb_clear_bits(struct twl4030_usb *twl, u8 reg, u8 bits)
+{
+        return twl4030_usb_write(twl, reg + 2, bits);
+}
+
+/*-------------------------------------------------------------------------*/
+
+static enum linkstat twl4030_usb_linkstat(struct twl4030_usb *twl)
+{
+        int     status;
+        int     linkstat = USB_LINK_UNKNOWN;
+
+        /* STS_HW_CONDITIONS */
+        status = twl4030_readb(twl, TWL4030_MODULE_PM_MASTER, 0x0f);
+        if (status < 0)
+                dev_err(twl->dev, "USB link status err %d\n", status);
+        else if (status & BIT(7))
+                linkstat = USB_LINK_VBUS;
+        else if (status & BIT(2))
+                linkstat = USB_LINK_ID;
+        else
+                linkstat = USB_LINK_NONE;
+
+        dev_dbg(twl->dev, "HW_CONDITIONS 0x%02x/%d; link %d\n",
+                        status, status, linkstat);
+
+        /* REVISIT this assumes host and peripheral controllers
+         * are registered, and that both are active...
+         */
+
+        spin_lock_irq(&twl->lock);
+        twl->linkstat = linkstat;
+        if (linkstat == USB_LINK_ID) {
+                twl->otg.default_a = true;
+                twl->otg.state = OTG_STATE_A_IDLE;
+        } else {
+                twl->otg.default_a = false;
+                twl->otg.state = OTG_STATE_B_IDLE;
+        }
+        spin_unlock_irq(&twl->lock);
+
+        return linkstat;
+}
+
+static void twl4030_usb_set_mode(struct twl4030_usb *twl, int mode)
+{
+        twl->usb_mode = mode;
+
+        switch (mode) {
+        case T2_USB_MODE_ULPI:
+                twl4030_usb_clear_bits(twl, IFC_CTRL, IFC_CTRL_CARKITMODE);
+                twl4030_usb_set_bits(twl, POWER_CTRL, POWER_CTRL_OTG_ENAB);
+                twl4030_usb_clear_bits(twl, FUNC_CTRL,
+                                        FUNC_CTRL_XCVRSELECT_MASK |
+                                        FUNC_CTRL_OPMODE_MASK);
+                break;
+        case -1:
+                /* FIXME: power on defaults */
+                break;
+        default:
+                dev_err(twl->dev, "unsupported T2 transceiver mode %d\n",
+                                mode);
+                break;
+        };
+}
+
+static void twl4030_i2c_access(struct twl4030_usb *twl, int on)
+{
+        unsigned long timeout;
+        int val = twl4030_usb_read(twl, PHY_CLK_CTRL);
+
+        if (val >= 0) {
+                if (on) {
+                        /* enable DPLL to access PHY registers over I2C */
+                        val |= REQ_PHY_DPLL_CLK;
+                        WARN_ON(twl4030_usb_write_verify(twl, PHY_CLK_CTRL,
+                                                (u8)val) < 0);
+
+                        timeout = jiffies + HZ;
+                        while (!(twl4030_usb_read(twl, PHY_CLK_CTRL_STS) &
+                                                        PHY_DPLL_CLK)
+                                && time_before(jiffies, timeout))
+                                        udelay(10);
+                        if (!(twl4030_usb_read(twl, PHY_CLK_CTRL_STS) &
+                                                        PHY_DPLL_CLK))
+                                dev_err(twl->dev, "Timeout setting T2 HSUSB "
+                                                "PHY DPLL clock\n");
+                } else {
+                        /* let ULPI control the DPLL clock */
+                        val &= ~REQ_PHY_DPLL_CLK;
+                        WARN_ON(twl4030_usb_write_verify(twl, PHY_CLK_CTRL,
+                                                (u8)val) < 0);
+                }
+        }
+}
+
+static void twl4030_phy_power(struct twl4030_usb *twl, int on)
+{
+        u8 pwr;
+
+        pwr = twl4030_usb_read(twl, PHY_PWR_CTRL);
+        if (on) {
+                pwr &= ~PHY_PWR_PHYPWD;
+                WARN_ON(twl4030_usb_write_verify(twl, PHY_PWR_CTRL, pwr) < 0);
+                twl4030_usb_write(twl, PHY_CLK_CTRL,
+                                  twl4030_usb_read(twl, PHY_CLK_CTRL) |
+                                        (PHY_CLK_CTRL_CLOCKGATING_EN |
+                                                PHY_CLK_CTRL_CLK32K_EN));
+        } else  {
+                pwr |= PHY_PWR_PHYPWD;
+                WARN_ON(twl4030_usb_write_verify(twl, PHY_PWR_CTRL, pwr) < 0);
+        }
+}
+
+static void twl4030_phy_suspend(struct twl4030_usb *twl, int controller_off)
+{
+        if (twl->asleep)
+                return;
+
+        twl4030_phy_power(twl, 0);
+        twl->asleep = 1;
+}
+
+static void twl4030_phy_resume(struct twl4030_usb *twl)
+{
+        if (!twl->asleep)
+                return;
+
+        twl4030_phy_power(twl, 1);
+        twl4030_i2c_access(twl, 1);
+        twl4030_usb_set_mode(twl, twl->usb_mode);
+        if (twl->usb_mode == T2_USB_MODE_ULPI)
+                twl4030_i2c_access(twl, 0);
+        twl->asleep = 0;
+}
+
+static void twl4030_usb_ldo_init(struct twl4030_usb *twl)
+{
+        /* Enable writing to power configuration registers */
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_MASTER, 0xC0, PROTECT_KEY);
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_MASTER, 0x0C, PROTECT_KEY);
+
+        /* put VUSB3V1 LDO in active state */
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, 0, VUSB_DEDICATED2);
+
+        /* input to VUSB3V1 LDO is from VBAT, not VBUS */
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, 0x14, VUSB_DEDICATED1);
+
+        /* turn on 3.1V regulator */
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, 0x20, VUSB3V1_DEV_GRP);
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, 0, VUSB3V1_TYPE);
+
+        /* turn on 1.5V regulator */
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, 0x20, VUSB1V5_DEV_GRP);
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, 0, VUSB1V5_TYPE);
+
+        /* turn on 1.8V regulator */
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, 0x20, VUSB1V8_DEV_GRP);
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER, 0, VUSB1V8_TYPE);
+
+        /* disable access to power configuration registers */
+        twl4030_i2c_write_u8(TWL4030_MODULE_PM_MASTER, 0, PROTECT_KEY);
+}
+
+static ssize_t twl4030_usb_vbus_show(struct device *dev,
+                struct device_attribute *attr, char *buf)
+{
+        struct twl4030_usb *twl = dev_get_drvdata(dev);
+        unsigned long flags;
+        int ret = -EINVAL;
+
+        spin_lock_irqsave(&twl->lock, flags);
+        ret = sprintf(buf, "%s\n",
+                        (twl->linkstat == USB_LINK_VBUS) ? "on" : "off");
+        spin_unlock_irqrestore(&twl->lock, flags);
+
+        return ret;
+}
+static DEVICE_ATTR(vbus, 0444, twl4030_usb_vbus_show, NULL);
+
+static irqreturn_t twl4030_usb_irq(int irq, void *_twl)
+{
+        struct twl4030_usb *twl = _twl;
+        int status;
+
+#ifdef CONFIG_LOCKDEP
+        /* WORKAROUND for lockdep forcing IRQF_DISABLED on us, which
+         * we don't want and can't tolerate.  Although it might be
+         * friendlier not to borrow this thread context...
+         */
+        local_irq_enable();
+#endif
+
+        status = twl4030_usb_linkstat(twl);
+        if (status != USB_LINK_UNKNOWN) {
+
+                /* FIXME add a set_power() method so that B-devices can
+                 * configure the charger appropriately.  It's not always
+                 * correct to consume VBUS power, and how much current to
+                 * consume is a function of the USB configuration chosen
+                 * by the host.
+                 *
+                 * REVISIT usb_gadget_vbus_connect(...) as needed, ditto
+                 * its disconnect() sibling, when changing to/from the
+                 * USB_LINK_VBUS state.  musb_hdrc won't care until it
+                 * starts to handle softconnect right.
+                 */
+                twl4030charger_usb_en(status == USB_LINK_VBUS);
+
+                if (status == USB_LINK_NONE)
+                        twl4030_phy_suspend(twl, 0);
+                else
+                        twl4030_phy_resume(twl);
+        }
+        sysfs_notify(&twl->dev->kobj, NULL, "vbus");
+
+        return IRQ_HANDLED;
+}
+
+static int twl4030_set_suspend(struct otg_transceiver *x, int suspend)
+{
+        struct twl4030_usb *twl = xceiv_to_twl(x);
+
+        if (suspend)
+                twl4030_phy_suspend(twl, 1);
+        else
+                twl4030_phy_resume(twl);
+
+        return 0;
+}
+
+static int twl4030_set_peripheral(struct otg_transceiver *x,
+                struct usb_gadget *gadget)
+{
+        struct twl4030_usb *twl;
+
+        if (!x)
+                return -ENODEV;
+
+        twl = xceiv_to_twl(x);
+        twl->otg.gadget = gadget;
+        if (!gadget)
+                twl->otg.state = OTG_STATE_UNDEFINED;
+
+        return 0;
+}
+
+static int twl4030_set_host(struct otg_transceiver *x, struct usb_bus *host)
+{
+        struct twl4030_usb *twl;
+
+        if (!x)
+                return -ENODEV;
+
+        twl = xceiv_to_twl(x);
+        twl->otg.host = host;
+        if (!host)
+                twl->otg.state = OTG_STATE_UNDEFINED;
+
+        return 0;
+}
+
+static int __init twl4030_usb_probe(struct platform_device *pdev)
+{
+        struct twl4030_usb_data *pdata = pdev->dev.platform_data;
+        struct twl4030_usb      *twl;
+        int                     status;
+
+        if (!pdata) {
+                dev_dbg(&pdev->dev, "platform_data not available\n");
+                return -EINVAL;
+        }
+
+        twl = kzalloc(sizeof *twl, GFP_KERNEL);
+        if (!twl)
+                return -ENOMEM;
+
+        twl->dev                = &pdev->dev;
+        twl->irq                = platform_get_irq(pdev, 0);
+        twl->otg.dev            = twl->dev;
+        twl->otg.label          = "twl4030";
+        twl->otg.set_host       = twl4030_set_host;
+        twl->otg.set_peripheral = twl4030_set_peripheral;
+        twl->otg.set_suspend    = twl4030_set_suspend;
+        twl->usb_mode           = pdata->usb_mode;
+        twl->asleep             = 1;
+
+        /* init spinlock for workqueue */
+        spin_lock_init(&twl->lock);
+
+        twl4030_usb_ldo_init(twl);
+        otg_set_transceiver(&twl->otg);
+
+        platform_set_drvdata(pdev, twl);
+        if (device_create_file(&pdev->dev, &dev_attr_vbus))
+                dev_warn(&pdev->dev, "could not create sysfs file\n");
+
+        /* Our job is to use irqs and status from the power module
+         * to keep the transceiver disabled when nothing's connected.
+         *
+         * FIXME we actually shouldn't start enabling it until the
+         * USB controller drivers have said they're ready, by calling
+         * set_host() and/or set_peripheral() ... OTG_capable boards
+         * need both handles, otherwise just one suffices.
+         */
+        twl->irq_enabled = true;
+        status = request_irq(twl->irq, twl4030_usb_irq,
+                        IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+                        "twl4030_usb", twl);
+        if (status < 0) {
+                dev_dbg(&pdev->dev, "can't get IRQ %d, err %d\n",
+                        twl->irq, status);
+                kfree(twl);
+                return status;
+        }
+
+        /* The IRQ handler just handles changes from the previous states
+         * of the ID and VBUS pins ... in probe() we must initialize that
+         * previous state.  The easy way:  fake an IRQ.
+         *
+         * REVISIT:  a real IRQ might have happened already, if PREEMPT is
+         * enabled.  Else the IRQ may not yet be configured or enabled,
+         * because of scheduling delays.
+         */
+        twl4030_usb_irq(twl->irq, twl);
+
+        dev_info(&pdev->dev, "Initialized TWL4030 USB module\n");
+        return 0;
+}
+
+static int __exit twl4030_usb_remove(struct platform_device *pdev)
+{
+        struct twl4030_usb *twl = platform_get_drvdata(pdev);
+        int val;
+
+        free_irq(twl->irq, twl);
+        device_remove_file(twl->dev, &dev_attr_vbus);
+
+        /* set transceiver mode to power on defaults */
+        twl4030_usb_set_mode(twl, -1);
+
+        /* autogate 60MHz ULPI clock,
+         * clear dpll clock request for i2c access,
+         * disable 32KHz
+         */
+        val = twl4030_usb_read(twl, PHY_CLK_CTRL);
+        if (val >= 0) {
+                val |= PHY_CLK_CTRL_CLOCKGATING_EN;
+                val &= ~(PHY_CLK_CTRL_CLK32K_EN | REQ_PHY_DPLL_CLK);
+                twl4030_usb_write(twl, PHY_CLK_CTRL, (u8)val);
+        }
+
+        /* disable complete OTG block */
+        twl4030_usb_clear_bits(twl, POWER_CTRL, POWER_CTRL_OTG_ENAB);
+
+        twl4030_phy_power(twl, 0);
+
+        kfree(twl);
+
+        return 0;
+}
+
+static struct platform_driver twl4030_usb_driver = {
+        .probe          = twl4030_usb_probe,
+        .remove         = __exit_p(twl4030_usb_remove),
+        .driver         = {
+                .name   = "twl4030_usb",
+                .owner  = THIS_MODULE,
+        },
+};
+
+static int __init twl4030_usb_init(void)
+{
+        return platform_driver_register(&twl4030_usb_driver);
+}
+subsys_initcall(twl4030_usb_init);
+
+static void __exit twl4030_usb_exit(void)
+{
+        platform_driver_unregister(&twl4030_usb_driver);
+}
+module_exit(twl4030_usb_exit);
+
+MODULE_ALIAS("platform:twl4030_usb");
+MODULE_AUTHOR("Texas Instruments, Inc, Nokia Corporation");
+MODULE_DESCRIPTION("TWL4030 USB transceiver driver");
+MODULE_LICENSE("GPL");