Logo Search packages:      
Sourcecode: linux version File versions  Download package

isp1301_omap.c

/*
 * isp1301_omap - ISP 1301 USB transceiver, talking to OMAP OTG controller
 *
 * Copyright (C) 2004 Texas Instruments
 * Copyright (C) 2004 David Brownell
 *
 * 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/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/usb.h>
#include <linux/usb/otg.h>
#include <linux/i2c.h>
#include <linux/workqueue.h>

#include <asm/irq.h>
#include <asm/arch/usb.h>


#ifndef     DEBUG
#undef      VERBOSE
#endif


#define     DRIVER_VERSION    "24 August 2004"
#define     DRIVER_NAME (isp1301_driver.driver.name)

MODULE_DESCRIPTION("ISP1301 USB OTG Transceiver Driver");
MODULE_LICENSE("GPL");

struct isp1301 {
      struct otg_transceiver  otg;
      struct i2c_client client;
      void              (*i2c_release)(struct device *dev);

      int               irq;
      int               irq_type;

      u32               last_otg_ctrl;
      unsigned          working:1;

      struct timer_list timer;

      /* use keventd context to change the state for us */
      struct work_struct      work;

      unsigned long           todo;
#           define WORK_UPDATE_ISP  0     /* update ISP from OTG */
#           define WORK_UPDATE_OTG  1     /* update OTG from ISP */
#           define WORK_HOST_RESUME 4     /* resume host */
#           define WORK_TIMER 6     /* timer fired */
#           define WORK_STOP  7     /* don't resubmit */
};


/* bits in OTG_CTRL_REG */

#define     OTG_XCEIV_OUTPUTS \
      (OTG_ASESSVLD|OTG_BSESSEND|OTG_BSESSVLD|OTG_VBUSVLD|OTG_ID)
#define     OTG_XCEIV_INPUTS \
      (OTG_PULLDOWN|OTG_PULLUP|OTG_DRV_VBUS|OTG_PD_VBUS|OTG_PU_VBUS|OTG_PU_ID)
#define     OTG_CTRL_BITS \
      (OTG_A_BUSREQ|OTG_A_SETB_HNPEN|OTG_B_BUSREQ|OTG_B_HNPEN|OTG_BUSDROP)
      /* and OTG_PULLUP is sometimes written */

#define     OTG_CTRL_MASK     (OTG_DRIVER_SEL| \
      OTG_XCEIV_OUTPUTS|OTG_XCEIV_INPUTS| \
      OTG_CTRL_BITS)


/*-------------------------------------------------------------------------*/

#ifdef      CONFIG_MACH_OMAP_H2

/* board-specific PM hooks */

#include <asm/gpio.h>
#include <asm/arch/mux.h>
#include <asm/mach-types.h>


#if   defined(CONFIG_TPS65010) || defined(CONFIG_TPS65010_MODULE)

#include <asm/arch/tps65010.h>

#else

static inline int tps65010_set_vbus_draw(unsigned mA)
{
      pr_debug("tps65010: draw %d mA (STUB)\n", mA);
      return 0;
}

#endif

static void enable_vbus_draw(struct isp1301 *isp, unsigned mA)
{
      int status = tps65010_set_vbus_draw(mA);
      if (status < 0)
            pr_debug("  VBUS %d mA error %d\n", mA, status);
}

static void enable_vbus_source(struct isp1301 *isp)
{
      /* this board won't supply more than 8mA vbus power.
       * some boards can switch a 100ma "unit load" (or more).
       */
}


/* products will deliver OTG messages with LEDs, GUI, etc */
static inline void notresponding(struct isp1301 *isp)
{
      printk(KERN_NOTICE "OTG device not responding.\n");
}


#endif

/*-------------------------------------------------------------------------*/

/* only two addresses possible */
#define     ISP_BASE          0x2c
static unsigned short normal_i2c[] = {
      ISP_BASE, ISP_BASE + 1,
      I2C_CLIENT_END };

I2C_CLIENT_INSMOD;

static struct i2c_driver isp1301_driver;

/* smbus apis are used for portability */

static inline u8
isp1301_get_u8(struct isp1301 *isp, u8 reg)
{
      return i2c_smbus_read_byte_data(&isp->client, reg + 0);
}

static inline int
isp1301_get_u16(struct isp1301 *isp, u8 reg)
{
      return i2c_smbus_read_word_data(&isp->client, reg);
}

static inline int
isp1301_set_bits(struct isp1301 *isp, u8 reg, u8 bits)
{
      return i2c_smbus_write_byte_data(&isp->client, reg + 0, bits);
}

static inline int
isp1301_clear_bits(struct isp1301 *isp, u8 reg, u8 bits)
{
      return i2c_smbus_write_byte_data(&isp->client, reg + 1, bits);
}

/*-------------------------------------------------------------------------*/

/* identification */
#define     ISP1301_VENDOR_ID       0x00  /* u16 read */
#define     ISP1301_PRODUCT_ID            0x02  /* u16 read */
#define     ISP1301_BCD_DEVICE            0x14  /* u16 read */

#define     I2C_VENDOR_ID_PHILIPS         0x04cc
#define     I2C_PRODUCT_ID_PHILIPS_1301   0x1301

/* operational registers */
#define     ISP1301_MODE_CONTROL_1        0x04  /* u8 read, set, +1 clear */
#     define      MC1_SPEED_REG           (1 << 0)
#     define      MC1_SUSPEND_REG         (1 << 1)
#     define      MC1_DAT_SE0       (1 << 2)
#     define      MC1_TRANSPARENT         (1 << 3)
#     define      MC1_BDIS_ACON_EN  (1 << 4)
#     define      MC1_OE_INT_EN           (1 << 5)
#     define      MC1_UART_EN       (1 << 6)
#     define      MC1_MASK          0x7f
#define     ISP1301_MODE_CONTROL_2        0x12  /* u8 read, set, +1 clear */
#     define      MC2_GLOBAL_PWR_DN (1 << 0)
#     define      MC2_SPD_SUSP_CTRL (1 << 1)
#     define      MC2_BI_DI         (1 << 2)
#     define      MC2_TRANSP_BDIR0  (1 << 3)
#     define      MC2_TRANSP_BDIR1  (1 << 4)
#     define      MC2_AUDIO_EN            (1 << 5)
#     define      MC2_PSW_EN        (1 << 6)
#     define      MC2_EN2V7         (1 << 7)
#define     ISP1301_OTG_CONTROL_1         0x06  /* u8 read, set, +1 clear */
#     define      OTG1_DP_PULLUP          (1 << 0)
#     define      OTG1_DM_PULLUP          (1 << 1)
#     define      OTG1_DP_PULLDOWN  (1 << 2)
#     define      OTG1_DM_PULLDOWN  (1 << 3)
#     define      OTG1_ID_PULLDOWN  (1 << 4)
#     define      OTG1_VBUS_DRV           (1 << 5)
#     define      OTG1_VBUS_DISCHRG (1 << 6)
#     define      OTG1_VBUS_CHRG          (1 << 7)
#define     ISP1301_OTG_STATUS            0x10  /* u8 readonly */
#     define      OTG_B_SESS_END          (1 << 6)
#     define      OTG_B_SESS_VLD          (1 << 7)

#define     ISP1301_INTERRUPT_SOURCE      0x08  /* u8 read */
#define     ISP1301_INTERRUPT_LATCH       0x0A  /* u8 read, set, +1 clear */

#define     ISP1301_INTERRUPT_FALLING     0x0C  /* u8 read, set, +1 clear */
#define     ISP1301_INTERRUPT_RISING      0x0E  /* u8 read, set, +1 clear */

/* same bitfields in all interrupt registers */
#     define      INTR_VBUS_VLD           (1 << 0)
#     define      INTR_SESS_VLD           (1 << 1)
#     define      INTR_DP_HI        (1 << 2)
#     define      INTR_ID_GND       (1 << 3)
#     define      INTR_DM_HI        (1 << 4)
#     define      INTR_ID_FLOAT           (1 << 5)
#     define      INTR_BDIS_ACON          (1 << 6)
#     define      INTR_CR_INT       (1 << 7)

/*-------------------------------------------------------------------------*/

static const char *state_string(enum usb_otg_state state)
{
      switch (state) {
      case OTG_STATE_A_IDLE:        return "a_idle";
      case OTG_STATE_A_WAIT_VRISE:  return "a_wait_vrise";
      case OTG_STATE_A_WAIT_BCON:   return "a_wait_bcon";
      case OTG_STATE_A_HOST:        return "a_host";
      case OTG_STATE_A_SUSPEND:     return "a_suspend";
      case OTG_STATE_A_PERIPHERAL:  return "a_peripheral";
      case OTG_STATE_A_WAIT_VFALL:  return "a_wait_vfall";
      case OTG_STATE_A_VBUS_ERR:    return "a_vbus_err";
      case OTG_STATE_B_IDLE:        return "b_idle";
      case OTG_STATE_B_SRP_INIT:    return "b_srp_init";
      case OTG_STATE_B_PERIPHERAL:  return "b_peripheral";
      case OTG_STATE_B_WAIT_ACON:   return "b_wait_acon";
      case OTG_STATE_B_HOST:        return "b_host";
      default:                return "UNDEFINED";
      }
}

static inline const char *state_name(struct isp1301 *isp)
{
      return state_string(isp->otg.state);
}

#ifdef      VERBOSE
#define     dev_vdbg                dev_dbg
#else
#define     dev_vdbg(dev, fmt, arg...)    do{}while(0)
#endif

/*-------------------------------------------------------------------------*/

/* NOTE:  some of this ISP1301 setup is specific to H2 boards;
 * not everything is guarded by board-specific checks, or even using
 * omap_usb_config data to deduce MC1_DAT_SE0 and MC2_BI_DI.
 *
 * ALSO:  this currently doesn't use ISP1301 low-power modes
 * while OTG is running.
 */

static void power_down(struct isp1301 *isp)
{
      isp->otg.state = OTG_STATE_UNDEFINED;

      // isp1301_set_bits(isp, ISP1301_MODE_CONTROL_2, MC2_GLOBAL_PWR_DN);
      isp1301_set_bits(isp, ISP1301_MODE_CONTROL_1, MC1_SUSPEND_REG);

      isp1301_clear_bits(isp, ISP1301_OTG_CONTROL_1, OTG1_ID_PULLDOWN);
      isp1301_clear_bits(isp, ISP1301_MODE_CONTROL_1, MC1_DAT_SE0);
}

static void power_up(struct isp1301 *isp)
{
      // isp1301_clear_bits(isp, ISP1301_MODE_CONTROL_2, MC2_GLOBAL_PWR_DN);
      isp1301_clear_bits(isp, ISP1301_MODE_CONTROL_1, MC1_SUSPEND_REG);

      /* do this only when cpu is driving transceiver,
       * so host won't see a low speed device...
       */
      isp1301_set_bits(isp, ISP1301_MODE_CONTROL_1, MC1_DAT_SE0);
}

#define     NO_HOST_SUSPEND

static int host_suspend(struct isp1301 *isp)
{
#ifdef      NO_HOST_SUSPEND
      return 0;
#else
      struct device     *dev;

      if (!isp->otg.host)
            return -ENODEV;

      /* Currently ASSUMES only the OTG port matters;
       * other ports could be active...
       */
      dev = isp->otg.host->controller;
      return dev->driver->suspend(dev, 3, 0);
#endif
}

static int host_resume(struct isp1301 *isp)
{
#ifdef      NO_HOST_SUSPEND
      return 0;
#else
      struct device     *dev;

      if (!isp->otg.host)
            return -ENODEV;

      dev = isp->otg.host->controller;
      return dev->driver->resume(dev, 0);
#endif
}

static int gadget_suspend(struct isp1301 *isp)
{
      isp->otg.gadget->b_hnp_enable = 0;
      isp->otg.gadget->a_hnp_support = 0;
      isp->otg.gadget->a_alt_hnp_support = 0;
      return usb_gadget_vbus_disconnect(isp->otg.gadget);
}

/*-------------------------------------------------------------------------*/

#define     TIMER_MINUTES     10
#define     TIMER_JIFFIES     (TIMER_MINUTES * 60 * HZ)

/* Almost all our I2C messaging comes from a work queue's task context.
 * NOTE: guaranteeing certain response times might mean we shouldn't
 * share keventd's work queue; a realtime task might be safest.
 */
void
isp1301_defer_work(struct isp1301 *isp, int work)
{
      int status;

      if (isp && !test_and_set_bit(work, &isp->todo)) {
            (void) get_device(&isp->client.dev);
            status = schedule_work(&isp->work);
            if (!status && !isp->working)
                  dev_vdbg(&isp->client.dev,
                        "work item %d may be lost\n", work);
      }
}

/* called from irq handlers */
static void a_idle(struct isp1301 *isp, const char *tag)
{
      if (isp->otg.state == OTG_STATE_A_IDLE)
            return;

      isp->otg.default_a = 1;
      if (isp->otg.host) {
            isp->otg.host->is_b_host = 0;
            host_suspend(isp);
      }
      if (isp->otg.gadget) {
            isp->otg.gadget->is_a_peripheral = 1;
            gadget_suspend(isp);
      }
      isp->otg.state = OTG_STATE_A_IDLE;
      isp->last_otg_ctrl = OTG_CTRL_REG = OTG_CTRL_REG & OTG_XCEIV_OUTPUTS;
      pr_debug("  --> %s/%s\n", state_name(isp), tag);
}

/* called from irq handlers */
static void b_idle(struct isp1301 *isp, const char *tag)
{
      if (isp->otg.state == OTG_STATE_B_IDLE)
            return;

      isp->otg.default_a = 0;
      if (isp->otg.host) {
            isp->otg.host->is_b_host = 1;
            host_suspend(isp);
      }
      if (isp->otg.gadget) {
            isp->otg.gadget->is_a_peripheral = 0;
            gadget_suspend(isp);
      }
      isp->otg.state = OTG_STATE_B_IDLE;
      isp->last_otg_ctrl = OTG_CTRL_REG = OTG_CTRL_REG & OTG_XCEIV_OUTPUTS;
      pr_debug("  --> %s/%s\n", state_name(isp), tag);
}

static void
dump_regs(struct isp1301 *isp, const char *label)
{
#ifdef      DEBUG
      u8    ctrl = isp1301_get_u8(isp, ISP1301_OTG_CONTROL_1);
      u8    status = isp1301_get_u8(isp, ISP1301_OTG_STATUS);
      u8    src = isp1301_get_u8(isp, ISP1301_INTERRUPT_SOURCE);

      pr_debug("otg: %06x, %s %s, otg/%02x stat/%02x.%02x\n",
            OTG_CTRL_REG, label, state_name(isp),
            ctrl, status, src);
      /* mode control and irq enables don't change much */
#endif
}

/*-------------------------------------------------------------------------*/

#ifdef      CONFIG_USB_OTG

/*
 * The OMAP OTG controller handles most of the OTG state transitions.
 *
 * We translate isp1301 outputs (mostly voltage comparator status) into
 * OTG inputs; OTG outputs (mostly pullup/pulldown controls) and HNP state
 * flags into isp1301 inputs ... and infer state transitions.
 */

#ifdef      VERBOSE

static void check_state(struct isp1301 *isp, const char *tag)
{
      enum usb_otg_state      state = OTG_STATE_UNDEFINED;
      u8                fsm = OTG_TEST_REG & 0x0ff;
      unsigned          extra = 0;

      switch (fsm) {

      /* default-b */
      case 0x0:
            state = OTG_STATE_B_IDLE;
            break;
      case 0x3:
      case 0x7:
            extra = 1;
      case 0x1:
            state = OTG_STATE_B_PERIPHERAL;
            break;
      case 0x11:
            state = OTG_STATE_B_SRP_INIT;
            break;

      /* extra dual-role default-b states */
      case 0x12:
      case 0x13:
      case 0x16:
            extra = 1;
      case 0x17:
            state = OTG_STATE_B_WAIT_ACON;
            break;
      case 0x34:
            state = OTG_STATE_B_HOST;
            break;

      /* default-a */
      case 0x36:
            state = OTG_STATE_A_IDLE;
            break;
      case 0x3c:
            state = OTG_STATE_A_WAIT_VFALL;
            break;
      case 0x7d:
            state = OTG_STATE_A_VBUS_ERR;
            break;
      case 0x9e:
      case 0x9f:
            extra = 1;
      case 0x89:
            state = OTG_STATE_A_PERIPHERAL;
            break;
      case 0xb7:
            state = OTG_STATE_A_WAIT_VRISE;
            break;
      case 0xb8:
            state = OTG_STATE_A_WAIT_BCON;
            break;
      case 0xb9:
            state = OTG_STATE_A_HOST;
            break;
      case 0xba:
            state = OTG_STATE_A_SUSPEND;
            break;
      default:
            break;
      }
      if (isp->otg.state == state && !extra)
            return;
      pr_debug("otg: %s FSM %s/%02x, %s, %06x\n", tag,
            state_string(state), fsm, state_name(isp), OTG_CTRL_REG);
}

#else

static inline void check_state(struct isp1301 *isp, const char *tag) { }

#endif

/* outputs from ISP1301_INTERRUPT_SOURCE */
static void update_otg1(struct isp1301 *isp, u8 int_src)
{
      u32   otg_ctrl;

      otg_ctrl = OTG_CTRL_REG
                  & OTG_CTRL_MASK
                  & ~OTG_XCEIV_INPUTS
                  & ~(OTG_ID|OTG_ASESSVLD|OTG_VBUSVLD);
      if (int_src & INTR_SESS_VLD)
            otg_ctrl |= OTG_ASESSVLD;
      else if (isp->otg.state == OTG_STATE_A_WAIT_VFALL) {
            a_idle(isp, "vfall");
            otg_ctrl &= ~OTG_CTRL_BITS;
      }
      if (int_src & INTR_VBUS_VLD)
            otg_ctrl |= OTG_VBUSVLD;
      if (int_src & INTR_ID_GND) {        /* default-A */
            if (isp->otg.state == OTG_STATE_B_IDLE
                        || isp->otg.state == OTG_STATE_UNDEFINED) {
                  a_idle(isp, "init");
                  return;
            }
      } else {                      /* default-B */
            otg_ctrl |= OTG_ID;
            if (isp->otg.state == OTG_STATE_A_IDLE
                        || isp->otg.state == OTG_STATE_UNDEFINED) {
                  b_idle(isp, "init");
                  return;
            }
      }
      OTG_CTRL_REG = otg_ctrl;
}

/* outputs from ISP1301_OTG_STATUS */
static void update_otg2(struct isp1301 *isp, u8 otg_status)
{
      u32   otg_ctrl;

      otg_ctrl = OTG_CTRL_REG
                  & OTG_CTRL_MASK
                  & ~OTG_XCEIV_INPUTS
                  & ~(OTG_BSESSVLD|OTG_BSESSEND);
      if (otg_status & OTG_B_SESS_VLD)
            otg_ctrl |= OTG_BSESSVLD;
      else if (otg_status & OTG_B_SESS_END)
            otg_ctrl |= OTG_BSESSEND;
      OTG_CTRL_REG = otg_ctrl;
}

/* inputs going to ISP1301 */
static void otg_update_isp(struct isp1301 *isp)
{
      u32   otg_ctrl, otg_change;
      u8    set = OTG1_DM_PULLDOWN, clr = OTG1_DM_PULLUP;

      otg_ctrl = OTG_CTRL_REG;
      otg_change = otg_ctrl ^ isp->last_otg_ctrl;
      isp->last_otg_ctrl = otg_ctrl;
      otg_ctrl = otg_ctrl & OTG_XCEIV_INPUTS;

      switch (isp->otg.state) {
      case OTG_STATE_B_IDLE:
      case OTG_STATE_B_PERIPHERAL:
      case OTG_STATE_B_SRP_INIT:
            if (!(otg_ctrl & OTG_PULLUP)) {
                  // if (otg_ctrl & OTG_B_HNPEN) {
                  if (isp->otg.gadget->b_hnp_enable) {
                        isp->otg.state = OTG_STATE_B_WAIT_ACON;
                        pr_debug("  --> b_wait_acon\n");
                  }
                  goto pulldown;
            }
pullup:
            set |= OTG1_DP_PULLUP;
            clr |= OTG1_DP_PULLDOWN;
            break;
      case OTG_STATE_A_SUSPEND:
      case OTG_STATE_A_PERIPHERAL:
            if (otg_ctrl & OTG_PULLUP)
                  goto pullup;
            /* FALLTHROUGH */
      // case OTG_STATE_B_WAIT_ACON:
      default:
pulldown:
            set |= OTG1_DP_PULLDOWN;
            clr |= OTG1_DP_PULLUP;
            break;
      }

#     define toggle(OTG,ISP) do { \
            if (otg_ctrl & OTG) set |= ISP; \
            else clr |= ISP; \
            } while (0)

      if (!(isp->otg.host))
            otg_ctrl &= ~OTG_DRV_VBUS;

      switch (isp->otg.state) {
      case OTG_STATE_A_SUSPEND:
            if (otg_ctrl & OTG_DRV_VBUS) {
                  set |= OTG1_VBUS_DRV;
                  break;
            }
            /* HNP failed for some reason (A_AIDL_BDIS timeout) */
            notresponding(isp);

            /* FALLTHROUGH */
      case OTG_STATE_A_VBUS_ERR:
            isp->otg.state = OTG_STATE_A_WAIT_VFALL;
            pr_debug("  --> a_wait_vfall\n");
            /* FALLTHROUGH */
      case OTG_STATE_A_WAIT_VFALL:
            /* FIXME usbcore thinks port power is still on ... */
            clr |= OTG1_VBUS_DRV;
            break;
      case OTG_STATE_A_IDLE:
            if (otg_ctrl & OTG_DRV_VBUS) {
                  isp->otg.state = OTG_STATE_A_WAIT_VRISE;
                  pr_debug("  --> a_wait_vrise\n");
            }
            /* FALLTHROUGH */
      default:
            toggle(OTG_DRV_VBUS, OTG1_VBUS_DRV);
      }

      toggle(OTG_PU_VBUS, OTG1_VBUS_CHRG);
      toggle(OTG_PD_VBUS, OTG1_VBUS_DISCHRG);

#     undef toggle

      isp1301_set_bits(isp, ISP1301_OTG_CONTROL_1, set);
      isp1301_clear_bits(isp, ISP1301_OTG_CONTROL_1, clr);

      /* HNP switch to host or peripheral; and SRP */
      if (otg_change & OTG_PULLUP) {
            switch (isp->otg.state) {
            case OTG_STATE_B_IDLE:
                  if (clr & OTG1_DP_PULLUP)
                        break;
                  isp->otg.state = OTG_STATE_B_PERIPHERAL;
                  pr_debug("  --> b_peripheral\n");
                  break;
            case OTG_STATE_A_SUSPEND:
                  if (clr & OTG1_DP_PULLUP)
                        break;
                  isp->otg.state = OTG_STATE_A_PERIPHERAL;
                  pr_debug("  --> a_peripheral\n");
                  break;
            default:
                  break;
            }
            OTG_CTRL_REG |= OTG_PULLUP;
      }

      check_state(isp, __FUNCTION__);
      dump_regs(isp, "otg->isp1301");
}

static irqreturn_t omap_otg_irq(int irq, void *_isp)
{
      u16         otg_irq = OTG_IRQ_SRC_REG;
      u32         otg_ctrl;
      int         ret = IRQ_NONE;
      struct isp1301    *isp = _isp;

      /* update ISP1301 transciever from OTG controller */
      if (otg_irq & OPRT_CHG) {
            OTG_IRQ_SRC_REG = OPRT_CHG;
            isp1301_defer_work(isp, WORK_UPDATE_ISP);
            ret = IRQ_HANDLED;

      /* SRP to become b_peripheral failed */
      } else if (otg_irq & B_SRP_TMROUT) {
            pr_debug("otg: B_SRP_TIMEOUT, %06x\n", OTG_CTRL_REG);
            notresponding(isp);

            /* gadget drivers that care should monitor all kinds of
             * remote wakeup (SRP, normal) using their own timer
             * to give "check cable and A-device" messages.
             */
            if (isp->otg.state == OTG_STATE_B_SRP_INIT)
                  b_idle(isp, "srp_timeout");

            OTG_IRQ_SRC_REG = B_SRP_TMROUT;
            ret = IRQ_HANDLED;

      /* HNP to become b_host failed */
      } else if (otg_irq & B_HNP_FAIL) {
            pr_debug("otg: %s B_HNP_FAIL, %06x\n",
                        state_name(isp), OTG_CTRL_REG);
            notresponding(isp);

            otg_ctrl = OTG_CTRL_REG;
            otg_ctrl |= OTG_BUSDROP;
            otg_ctrl &= OTG_CTRL_MASK & ~OTG_XCEIV_INPUTS;
            OTG_CTRL_REG = otg_ctrl;

            /* subset of b_peripheral()... */
            isp->otg.state = OTG_STATE_B_PERIPHERAL;
            pr_debug("  --> b_peripheral\n");

            OTG_IRQ_SRC_REG = B_HNP_FAIL;
            ret = IRQ_HANDLED;

      /* detect SRP from B-device ... */
      } else if (otg_irq & A_SRP_DETECT) {
            pr_debug("otg: %s SRP_DETECT, %06x\n",
                        state_name(isp), OTG_CTRL_REG);

            isp1301_defer_work(isp, WORK_UPDATE_OTG);
            switch (isp->otg.state) {
            case OTG_STATE_A_IDLE:
                  if (!isp->otg.host)
                        break;
                  isp1301_defer_work(isp, WORK_HOST_RESUME);
                  otg_ctrl = OTG_CTRL_REG;
                  otg_ctrl |= OTG_A_BUSREQ;
                  otg_ctrl &= ~(OTG_BUSDROP|OTG_B_BUSREQ)
                              & ~OTG_XCEIV_INPUTS
                              & OTG_CTRL_MASK;
                  OTG_CTRL_REG = otg_ctrl;
                  break;
            default:
                  break;
            }

            OTG_IRQ_SRC_REG = A_SRP_DETECT;
            ret = IRQ_HANDLED;

      /* timer expired:  T(a_wait_bcon) and maybe T(a_wait_vrise)
       * we don't track them separately
       */
      } else if (otg_irq & A_REQ_TMROUT) {
            otg_ctrl = OTG_CTRL_REG;
            pr_info("otg: BCON_TMOUT from %s, %06x\n",
                        state_name(isp), otg_ctrl);
            notresponding(isp);

            otg_ctrl |= OTG_BUSDROP;
            otg_ctrl &= ~OTG_A_BUSREQ & OTG_CTRL_MASK & ~OTG_XCEIV_INPUTS;
            OTG_CTRL_REG = otg_ctrl;
            isp->otg.state = OTG_STATE_A_WAIT_VFALL;

            OTG_IRQ_SRC_REG = A_REQ_TMROUT;
            ret = IRQ_HANDLED;

      /* A-supplied voltage fell too low; overcurrent */
      } else if (otg_irq & A_VBUS_ERR) {
            otg_ctrl = OTG_CTRL_REG;
            printk(KERN_ERR "otg: %s, VBUS_ERR %04x ctrl %06x\n",
                  state_name(isp), otg_irq, otg_ctrl);

            otg_ctrl |= OTG_BUSDROP;
            otg_ctrl &= ~OTG_A_BUSREQ & OTG_CTRL_MASK & ~OTG_XCEIV_INPUTS;
            OTG_CTRL_REG = otg_ctrl;
            isp->otg.state = OTG_STATE_A_VBUS_ERR;

            OTG_IRQ_SRC_REG = A_VBUS_ERR;
            ret = IRQ_HANDLED;

      /* switch driver; the transciever code activates it,
       * ungating the udc clock or resuming OHCI.
       */
      } else if (otg_irq & DRIVER_SWITCH) {
            int   kick = 0;

            otg_ctrl = OTG_CTRL_REG;
            printk(KERN_NOTICE "otg: %s, SWITCH to %s, ctrl %06x\n",
                        state_name(isp),
                        (otg_ctrl & OTG_DRIVER_SEL)
                              ? "gadget" : "host",
                        otg_ctrl);
            isp1301_defer_work(isp, WORK_UPDATE_ISP);

            /* role is peripheral */
            if (otg_ctrl & OTG_DRIVER_SEL) {
                  switch (isp->otg.state) {
                  case OTG_STATE_A_IDLE:
                        b_idle(isp, __FUNCTION__);
                        break;
                  default:
                        break;
                  }
                  isp1301_defer_work(isp, WORK_UPDATE_ISP);

            /* role is host */
            } else {
                  if (!(otg_ctrl & OTG_ID)) {
                        otg_ctrl &= OTG_CTRL_MASK & ~OTG_XCEIV_INPUTS;
                        OTG_CTRL_REG = otg_ctrl | OTG_A_BUSREQ;
                  }

                  if (isp->otg.host) {
                        switch (isp->otg.state) {
                        case OTG_STATE_B_WAIT_ACON:
                              isp->otg.state = OTG_STATE_B_HOST;
                              pr_debug("  --> b_host\n");
                              kick = 1;
                              break;
                        case OTG_STATE_A_WAIT_BCON:
                              isp->otg.state = OTG_STATE_A_HOST;
                              pr_debug("  --> a_host\n");
                              break;
                        case OTG_STATE_A_PERIPHERAL:
                              isp->otg.state = OTG_STATE_A_WAIT_BCON;
                              pr_debug("  --> a_wait_bcon\n");
                              break;
                        default:
                              break;
                        }
                        isp1301_defer_work(isp, WORK_HOST_RESUME);
                  }
            }

            OTG_IRQ_SRC_REG = DRIVER_SWITCH;
            ret = IRQ_HANDLED;

            if (kick)
                  usb_bus_start_enum(isp->otg.host,
                                    isp->otg.host->otg_port);
      }

      check_state(isp, __FUNCTION__);
      return ret;
}

static struct platform_device *otg_dev;

static int otg_init(struct isp1301 *isp)
{
      if (!otg_dev)
            return -ENODEV;

      dump_regs(isp, __FUNCTION__);
      /* some of these values are board-specific... */
      OTG_SYSCON_2_REG |= OTG_EN
            /* for B-device: */
            | SRP_GPDATA            /* 9msec Bdev D+ pulse */
            | SRP_GPDVBUS           /* discharge after VBUS pulse */
            // | (3 << 24)          /* 2msec VBUS pulse */
            /* for A-device: */
            | (0 << 20)       /* 200ms nominal A_WAIT_VRISE timer */
            | SRP_DPW         /* detect 167+ns SRP pulses */
            | SRP_DATA | SRP_VBUS   /* accept both kinds of SRP pulse */
            ;

      update_otg1(isp, isp1301_get_u8(isp, ISP1301_INTERRUPT_SOURCE));
      update_otg2(isp, isp1301_get_u8(isp, ISP1301_OTG_STATUS));

      check_state(isp, __FUNCTION__);
      pr_debug("otg: %s, %s %06x\n",
                  state_name(isp), __FUNCTION__, OTG_CTRL_REG);

      OTG_IRQ_EN_REG = DRIVER_SWITCH | OPRT_CHG
                  | B_SRP_TMROUT | B_HNP_FAIL
                  | A_VBUS_ERR | A_SRP_DETECT | A_REQ_TMROUT;
      OTG_SYSCON_2_REG |= OTG_EN;

      return 0;
}

static int otg_probe(struct platform_device *dev)
{
      // struct omap_usb_config *config = dev->platform_data;

      otg_dev = dev;
      return 0;
}

static int otg_remove(struct platform_device *dev)
{
      otg_dev = 0;
      return 0;
}

struct platform_driver omap_otg_driver = {
      .probe            = otg_probe,
      .remove           = otg_remove,
      .driver           = {
            .owner      = THIS_MODULE,
            .name = "omap_otg",
      },
};

static int otg_bind(struct isp1301 *isp)
{
      int   status;

      if (otg_dev)
            return -EBUSY;

      status = platform_driver_register(&omap_otg_driver);
      if (status < 0)
            return status;

      if (otg_dev)
            status = request_irq(otg_dev->resource[1].start, omap_otg_irq,
                        IRQF_DISABLED, DRIVER_NAME, isp);
      else
            status = -ENODEV;

      if (status < 0)
            platform_driver_unregister(&omap_otg_driver);
      return status;
}

static void otg_unbind(struct isp1301 *isp)
{
      if (!otg_dev)
            return;
      free_irq(otg_dev->resource[1].start, isp);
}

#else

/* OTG controller isn't clocked */

#endif      /* CONFIG_USB_OTG */

/*-------------------------------------------------------------------------*/

static void b_peripheral(struct isp1301 *isp)
{
      OTG_CTRL_REG = OTG_CTRL_REG & OTG_XCEIV_OUTPUTS;
      usb_gadget_vbus_connect(isp->otg.gadget);

#ifdef      CONFIG_USB_OTG
      enable_vbus_draw(isp, 8);
      otg_update_isp(isp);
#else
      enable_vbus_draw(isp, 100);
      /* UDC driver just set OTG_BSESSVLD */
      isp1301_set_bits(isp, ISP1301_OTG_CONTROL_1, OTG1_DP_PULLUP);
      isp1301_clear_bits(isp, ISP1301_OTG_CONTROL_1, OTG1_DP_PULLDOWN);
      isp->otg.state = OTG_STATE_B_PERIPHERAL;
      pr_debug("  --> b_peripheral\n");
      dump_regs(isp, "2periph");
#endif
}

static void isp_update_otg(struct isp1301 *isp, u8 stat)
{
      u8                isp_stat, isp_bstat;
      enum usb_otg_state      state = isp->otg.state;

      if (stat & INTR_BDIS_ACON)
            pr_debug("OTG:  BDIS_ACON, %s\n", state_name(isp));

      /* start certain state transitions right away */
      isp_stat = isp1301_get_u8(isp, ISP1301_INTERRUPT_SOURCE);
      if (isp_stat & INTR_ID_GND) {
            if (isp->otg.default_a) {
                  switch (state) {
                  case OTG_STATE_B_IDLE:
                        a_idle(isp, "idle");
                        /* FALLTHROUGH */
                  case OTG_STATE_A_IDLE:
                        enable_vbus_source(isp);
                        /* FALLTHROUGH */
                  case OTG_STATE_A_WAIT_VRISE:
                        /* we skip over OTG_STATE_A_WAIT_BCON, since
                         * the HC will transition to A_HOST (or
                         * A_SUSPEND!) without our noticing except
                         * when HNP is used.
                         */
                        if (isp_stat & INTR_VBUS_VLD)
                              isp->otg.state = OTG_STATE_A_HOST;
                        break;
                  case OTG_STATE_A_WAIT_VFALL:
                        if (!(isp_stat & INTR_SESS_VLD))
                              a_idle(isp, "vfell");
                        break;
                  default:
                        if (!(isp_stat & INTR_VBUS_VLD))
                              isp->otg.state = OTG_STATE_A_VBUS_ERR;
                        break;
                  }
                  isp_bstat = isp1301_get_u8(isp, ISP1301_OTG_STATUS);
            } else {
                  switch (state) {
                  case OTG_STATE_B_PERIPHERAL:
                  case OTG_STATE_B_HOST:
                  case OTG_STATE_B_WAIT_ACON:
                        usb_gadget_vbus_disconnect(isp->otg.gadget);
                        break;
                  default:
                        break;
                  }
                  if (state != OTG_STATE_A_IDLE)
                        a_idle(isp, "id");
                  if (isp->otg.host && state == OTG_STATE_A_IDLE)
                        isp1301_defer_work(isp, WORK_HOST_RESUME);
                  isp_bstat = 0;
            }
      } else {
            /* if user unplugged mini-A end of cable,
             * don't bypass A_WAIT_VFALL.
             */
            if (isp->otg.default_a) {
                  switch (state) {
                  default:
                        isp->otg.state = OTG_STATE_A_WAIT_VFALL;
                        break;
                  case OTG_STATE_A_WAIT_VFALL:
                        state = OTG_STATE_A_IDLE;
                        /* khubd may take a while to notice and
                         * handle this disconnect, so don't go
                         * to B_IDLE quite yet.
                         */
                        break;
                  case OTG_STATE_A_IDLE:
                        host_suspend(isp);
                        isp1301_clear_bits(isp, ISP1301_MODE_CONTROL_1,
                                    MC1_BDIS_ACON_EN);
                        isp->otg.state = OTG_STATE_B_IDLE;
                        OTG_CTRL_REG &= OTG_CTRL_REG & OTG_CTRL_MASK
                                    & ~OTG_CTRL_BITS;
                        break;
                  case OTG_STATE_B_IDLE:
                        break;
                  }
            }
            isp_bstat = isp1301_get_u8(isp, ISP1301_OTG_STATUS);

            switch (isp->otg.state) {
            case OTG_STATE_B_PERIPHERAL:
            case OTG_STATE_B_WAIT_ACON:
            case OTG_STATE_B_HOST:
                  if (likely(isp_bstat & OTG_B_SESS_VLD))
                        break;
                  enable_vbus_draw(isp, 0);
#ifndef     CONFIG_USB_OTG
                  /* UDC driver will clear OTG_BSESSVLD */
                  isp1301_set_bits(isp, ISP1301_OTG_CONTROL_1,
                                    OTG1_DP_PULLDOWN);
                  isp1301_clear_bits(isp, ISP1301_OTG_CONTROL_1,
                                    OTG1_DP_PULLUP);
                  dump_regs(isp, __FUNCTION__);
#endif
                  /* FALLTHROUGH */
            case OTG_STATE_B_SRP_INIT:
                  b_idle(isp, __FUNCTION__);
                  OTG_CTRL_REG &= OTG_CTRL_REG & OTG_XCEIV_OUTPUTS;
                  /* FALLTHROUGH */
            case OTG_STATE_B_IDLE:
                  if (isp->otg.gadget && (isp_bstat & OTG_B_SESS_VLD)) {
#ifdef      CONFIG_USB_OTG
                        update_otg1(isp, isp_stat);
                        update_otg2(isp, isp_bstat);
#endif
                        b_peripheral(isp);
                  } else if (!(isp_stat & (INTR_VBUS_VLD|INTR_SESS_VLD)))
                        isp_bstat |= OTG_B_SESS_END;
                  break;
            case OTG_STATE_A_WAIT_VFALL:
                  break;
            default:
                  pr_debug("otg: unsupported b-device %s\n",
                        state_name(isp));
                  break;
            }
      }

      if (state != isp->otg.state)
            pr_debug("  isp, %s -> %s\n",
                        state_string(state), state_name(isp));

#ifdef      CONFIG_USB_OTG
      /* update the OTG controller state to match the isp1301; may
       * trigger OPRT_CHG irqs for changes going to the isp1301.
       */
      update_otg1(isp, isp_stat);
      update_otg2(isp, isp_bstat);
      check_state(isp, __FUNCTION__);
#endif

      dump_regs(isp, "isp1301->otg");
}

/*-------------------------------------------------------------------------*/

static u8 isp1301_clear_latch(struct isp1301 *isp)
{
      u8 latch = isp1301_get_u8(isp, ISP1301_INTERRUPT_LATCH);
      isp1301_clear_bits(isp, ISP1301_INTERRUPT_LATCH, latch);
      return latch;
}

static void
isp1301_work(struct work_struct *work)
{
      struct isp1301    *isp = container_of(work, struct isp1301, work);
      int         stop;

      /* implicit lock:  we're the only task using this device */
      isp->working = 1;
      do {
            stop = test_bit(WORK_STOP, &isp->todo);

#ifdef      CONFIG_USB_OTG
            /* transfer state from otg engine to isp1301 */
            if (test_and_clear_bit(WORK_UPDATE_ISP, &isp->todo)) {
                  otg_update_isp(isp);
                  put_device(&isp->client.dev);
            }
#endif
            /* transfer state from isp1301 to otg engine */
            if (test_and_clear_bit(WORK_UPDATE_OTG, &isp->todo)) {
                  u8          stat = isp1301_clear_latch(isp);

                  isp_update_otg(isp, stat);
                  put_device(&isp->client.dev);
            }

            if (test_and_clear_bit(WORK_HOST_RESUME, &isp->todo)) {
                  u32   otg_ctrl;

                  /*
                   * skip A_WAIT_VRISE; hc transitions invisibly
                   * skip A_WAIT_BCON; same.
                   */
                  switch (isp->otg.state) {
                  case OTG_STATE_A_WAIT_BCON:
                  case OTG_STATE_A_WAIT_VRISE:
                        isp->otg.state = OTG_STATE_A_HOST;
                        pr_debug("  --> a_host\n");
                        otg_ctrl = OTG_CTRL_REG;
                        otg_ctrl |= OTG_A_BUSREQ;
                        otg_ctrl &= ~(OTG_BUSDROP|OTG_B_BUSREQ)
                                    & OTG_CTRL_MASK;
                        OTG_CTRL_REG = otg_ctrl;
                        break;
                  case OTG_STATE_B_WAIT_ACON:
                        isp->otg.state = OTG_STATE_B_HOST;
                        pr_debug("  --> b_host (acon)\n");
                        break;
                  case OTG_STATE_B_HOST:
                  case OTG_STATE_B_IDLE:
                  case OTG_STATE_A_IDLE:
                        break;
                  default:
                        pr_debug("  host resume in %s\n",
                                    state_name(isp));
                  }
                  host_resume(isp);
                  // mdelay(10);
                  put_device(&isp->client.dev);
            }

            if (test_and_clear_bit(WORK_TIMER, &isp->todo)) {
#ifdef      VERBOSE
                  dump_regs(isp, "timer");
                  if (!stop)
                        mod_timer(&isp->timer, jiffies + TIMER_JIFFIES);
#endif
                  put_device(&isp->client.dev);
            }

            if (isp->todo)
                  dev_vdbg(&isp->client.dev,
                        "work done, todo = 0x%lx\n",
                        isp->todo);
            if (stop) {
                  dev_dbg(&isp->client.dev, "stop\n");
                  break;
            }
      } while (isp->todo);
      isp->working = 0;
}

static irqreturn_t isp1301_irq(int irq, void *isp)
{
      isp1301_defer_work(isp, WORK_UPDATE_OTG);
      return IRQ_HANDLED;
}

static void isp1301_timer(unsigned long _isp)
{
      isp1301_defer_work((void *)_isp, WORK_TIMER);
}

/*-------------------------------------------------------------------------*/

static void isp1301_release(struct device *dev)
{
      struct isp1301    *isp;

      isp = container_of(dev, struct isp1301, client.dev);

      /* ugly -- i2c hijacks our memory hook to wait_for_completion() */
      if (isp->i2c_release)
            isp->i2c_release(dev);
      kfree (isp);
}

static struct isp1301 *the_transceiver;

static int isp1301_detach_client(struct i2c_client *i2c)
{
      struct isp1301    *isp;

      isp = container_of(i2c, struct isp1301, client);

      isp1301_clear_bits(isp, ISP1301_INTERRUPT_FALLING, ~0);
      isp1301_clear_bits(isp, ISP1301_INTERRUPT_RISING, ~0);
      free_irq(isp->irq, isp);
#ifdef      CONFIG_USB_OTG
      otg_unbind(isp);
#endif
      if (machine_is_omap_h2())
            omap_free_gpio(2);

      isp->timer.data = 0;
      set_bit(WORK_STOP, &isp->todo);
      del_timer_sync(&isp->timer);
      flush_scheduled_work();

      put_device(&i2c->dev);
      the_transceiver = 0;

      return i2c_detach_client(i2c);
}

/*-------------------------------------------------------------------------*/

/* NOTE:  three modes are possible here, only one of which
 * will be standards-conformant on any given system:
 *
 *  - OTG mode (dual-role), required if there's a Mini-AB connector
 *  - HOST mode, for when there's one or more A (host) connectors
 *  - DEVICE mode, for when there's a B/Mini-B (device) connector
 *
 * As a rule, you won't have an isp1301 chip unless it's there to
 * support the OTG mode.  Other modes help testing USB controllers
 * in isolation from (full) OTG support, or maybe so later board
 * revisions can help to support those feature.
 */

#ifdef      CONFIG_USB_OTG

static int isp1301_otg_enable(struct isp1301 *isp)
{
      power_up(isp);
      otg_init(isp);

      /* NOTE:  since we don't change this, this provides
       * a few more interrupts than are strictly needed.
       */
      isp1301_set_bits(isp, ISP1301_INTERRUPT_RISING,
            INTR_VBUS_VLD | INTR_SESS_VLD | INTR_ID_GND);
      isp1301_set_bits(isp, ISP1301_INTERRUPT_FALLING,
            INTR_VBUS_VLD | INTR_SESS_VLD | INTR_ID_GND);

      dev_info(&isp->client.dev, "ready for dual-role USB ...\n");

      return 0;
}

#endif

/* add or disable the host device+driver */
static int
isp1301_set_host(struct otg_transceiver *otg, struct usb_bus *host)
{
      struct isp1301    *isp = container_of(otg, struct isp1301, otg);

      if (!otg || isp != the_transceiver)
            return -ENODEV;

      if (!host) {
            OTG_IRQ_EN_REG = 0;
            power_down(isp);
            isp->otg.host = 0;
            return 0;
      }

#ifdef      CONFIG_USB_OTG
      isp->otg.host = host;
      dev_dbg(&isp->client.dev, "registered host\n");
      host_suspend(isp);
      if (isp->otg.gadget)
            return isp1301_otg_enable(isp);
      return 0;

#elif !defined(CONFIG_USB_GADGET_OMAP)
      // FIXME update its refcount
      isp->otg.host = host;

      power_up(isp);

      if (machine_is_omap_h2())
            isp1301_set_bits(isp, ISP1301_MODE_CONTROL_1, MC1_DAT_SE0);

      dev_info(&isp->client.dev, "A-Host sessions ok\n");
      isp1301_set_bits(isp, ISP1301_INTERRUPT_RISING,
            INTR_ID_GND);
      isp1301_set_bits(isp, ISP1301_INTERRUPT_FALLING,
            INTR_ID_GND);

      /* If this has a Mini-AB connector, this mode is highly
       * nonstandard ... but can be handy for testing, especially with
       * the Mini-A end of an OTG cable.  (Or something nonstandard
       * like MiniB-to-StandardB, maybe built with a gender mender.)
       */
      isp1301_set_bits(isp, ISP1301_OTG_CONTROL_1, OTG1_VBUS_DRV);

      dump_regs(isp, __FUNCTION__);

      return 0;

#else
      dev_dbg(&isp->client.dev, "host sessions not allowed\n");
      return -EINVAL;
#endif

}

static int
isp1301_set_peripheral(struct otg_transceiver *otg, struct usb_gadget *gadget)
{
      struct isp1301    *isp = container_of(otg, struct isp1301, otg);

      if (!otg || isp != the_transceiver)
            return -ENODEV;

      if (!gadget) {
            OTG_IRQ_EN_REG = 0;
            if (!isp->otg.default_a)
                  enable_vbus_draw(isp, 0);
            usb_gadget_vbus_disconnect(isp->otg.gadget);
            isp->otg.gadget = 0;
            power_down(isp);
            return 0;
      }

#ifdef      CONFIG_USB_OTG
      isp->otg.gadget = gadget;
      dev_dbg(&isp->client.dev, "registered gadget\n");
      /* gadget driver may be suspended until vbus_connect () */
      if (isp->otg.host)
            return isp1301_otg_enable(isp);
      return 0;

#elif !defined(CONFIG_USB_OHCI_HCD) && !defined(CONFIG_USB_OHCI_HCD_MODULE)
      isp->otg.gadget = gadget;
      // FIXME update its refcount

      OTG_CTRL_REG = (OTG_CTRL_REG & OTG_CTRL_MASK
                        & ~(OTG_XCEIV_OUTPUTS|OTG_CTRL_BITS))
                  | OTG_ID;
      power_up(isp);
      isp->otg.state = OTG_STATE_B_IDLE;

      if (machine_is_omap_h2())
            isp1301_set_bits(isp, ISP1301_MODE_CONTROL_1, MC1_DAT_SE0);

      isp1301_set_bits(isp, ISP1301_INTERRUPT_RISING,
            INTR_SESS_VLD);
      isp1301_set_bits(isp, ISP1301_INTERRUPT_FALLING,
            INTR_VBUS_VLD);
      dev_info(&isp->client.dev, "B-Peripheral sessions ok\n");
      dump_regs(isp, __FUNCTION__);

      /* If this has a Mini-AB connector, this mode is highly
       * nonstandard ... but can be handy for testing, so long
       * as you don't plug a Mini-A cable into the jack.
       */
      if (isp1301_get_u8(isp, ISP1301_INTERRUPT_SOURCE) & INTR_VBUS_VLD)
            b_peripheral(isp);

      return 0;

#else
      dev_dbg(&isp->client.dev, "peripheral sessions not allowed\n");
      return -EINVAL;
#endif
}


/*-------------------------------------------------------------------------*/

static int
isp1301_set_power(struct otg_transceiver *dev, unsigned mA)
{
      if (!the_transceiver)
            return -ENODEV;
      if (dev->state == OTG_STATE_B_PERIPHERAL)
            enable_vbus_draw(the_transceiver, mA);
      return 0;
}

static int
isp1301_start_srp(struct otg_transceiver *dev)
{
      struct isp1301    *isp = container_of(dev, struct isp1301, otg);
      u32         otg_ctrl;

      if (!dev || isp != the_transceiver
                  || isp->otg.state != OTG_STATE_B_IDLE)
            return -ENODEV;

      otg_ctrl = OTG_CTRL_REG;
      if (!(otg_ctrl & OTG_BSESSEND))
            return -EINVAL;

      otg_ctrl |= OTG_B_BUSREQ;
      otg_ctrl &= ~OTG_A_BUSREQ & OTG_CTRL_MASK;
      OTG_CTRL_REG = otg_ctrl;
      isp->otg.state = OTG_STATE_B_SRP_INIT;

      pr_debug("otg: SRP, %s ... %06x\n", state_name(isp), OTG_CTRL_REG);
#ifdef      CONFIG_USB_OTG
      check_state(isp, __FUNCTION__);
#endif
      return 0;
}

static int
isp1301_start_hnp(struct otg_transceiver *dev)
{
#ifdef      CONFIG_USB_OTG
      struct isp1301    *isp = container_of(dev, struct isp1301, otg);

      if (!dev || isp != the_transceiver)
            return -ENODEV;
      if (isp->otg.default_a && (isp->otg.host == NULL
                  || !isp->otg.host->b_hnp_enable))
            return -ENOTCONN;
      if (!isp->otg.default_a && (isp->otg.gadget == NULL
                  || !isp->otg.gadget->b_hnp_enable))
            return -ENOTCONN;

      /* We want hardware to manage most HNP protocol timings.
       * So do this part as early as possible...
       */
      switch (isp->otg.state) {
      case OTG_STATE_B_HOST:
            isp->otg.state = OTG_STATE_B_PERIPHERAL;
            /* caller will suspend next */
            break;
      case OTG_STATE_A_HOST:
#if 0
            /* autoconnect mode avoids irq latency bugs */
            isp1301_set_bits(isp, ISP1301_MODE_CONTROL_1,
                        MC1_BDIS_ACON_EN);
#endif
            /* caller must suspend then clear A_BUSREQ */
            usb_gadget_vbus_connect(isp->otg.gadget);
            OTG_CTRL_REG |= OTG_A_SETB_HNPEN;

            break;
      case OTG_STATE_A_PERIPHERAL:
            /* initiated by B-Host suspend */
            break;
      default:
            return -EILSEQ;
      }
      pr_debug("otg: HNP %s, %06x ...\n",
            state_name(isp), OTG_CTRL_REG);
      check_state(isp, __FUNCTION__);
      return 0;
#else
      /* srp-only */
      return -EINVAL;
#endif
}

/*-------------------------------------------------------------------------*/

/* no error returns, they'd just make bus scanning stop */
static int isp1301_probe(struct i2c_adapter *bus, int address, int kind)
{
      int               status;
      struct isp1301          *isp;
      struct i2c_client *i2c;

      if (the_transceiver)
            return 0;

      isp = kzalloc(sizeof *isp, GFP_KERNEL);
      if (!isp)
            return 0;

      INIT_WORK(&isp->work, isp1301_work);
      init_timer(&isp->timer);
      isp->timer.function = isp1301_timer;
      isp->timer.data = (unsigned long) isp;

      isp->irq = -1;
      isp->client.addr = address;
      i2c_set_clientdata(&isp->client, isp);
      isp->client.adapter = bus;
      isp->client.driver = &isp1301_driver;
      strlcpy(isp->client.name, DRIVER_NAME, I2C_NAME_SIZE);
      i2c = &isp->client;

      /* if this is a true probe, verify the chip ... */
      if (kind < 0) {
            status = isp1301_get_u16(isp, ISP1301_VENDOR_ID);
            if (status != I2C_VENDOR_ID_PHILIPS) {
                  dev_dbg(&bus->dev, "addr %d not philips id: %d\n",
                        address, status);
                  goto fail1;
            }
            status = isp1301_get_u16(isp, ISP1301_PRODUCT_ID);
            if (status != I2C_PRODUCT_ID_PHILIPS_1301) {
                  dev_dbg(&bus->dev, "%d not isp1301, %d\n",
                        address, status);
                  goto fail1;
            }
      }

      status = i2c_attach_client(i2c);
      if (status < 0) {
            dev_dbg(&bus->dev, "can't attach %s to device %d, err %d\n",
                        DRIVER_NAME, address, status);
fail1:
            kfree(isp);
            return 0;
      }
      isp->i2c_release = i2c->dev.release;
      i2c->dev.release = isp1301_release;

      /* initial development used chiprev 2.00 */
      status = i2c_smbus_read_word_data(i2c, ISP1301_BCD_DEVICE);
      dev_info(&i2c->dev, "chiprev %x.%02x, driver " DRIVER_VERSION "\n",
            status >> 8, status & 0xff);

      /* make like power-on reset */
      isp1301_clear_bits(isp, ISP1301_MODE_CONTROL_1, MC1_MASK);

      isp1301_set_bits(isp, ISP1301_MODE_CONTROL_2, MC2_BI_DI);
      isp1301_clear_bits(isp, ISP1301_MODE_CONTROL_2, ~MC2_BI_DI);

      isp1301_set_bits(isp, ISP1301_OTG_CONTROL_1,
                        OTG1_DM_PULLDOWN | OTG1_DP_PULLDOWN);
      isp1301_clear_bits(isp, ISP1301_OTG_CONTROL_1,
                        ~(OTG1_DM_PULLDOWN | OTG1_DP_PULLDOWN));

      isp1301_clear_bits(isp, ISP1301_INTERRUPT_LATCH, ~0);
      isp1301_clear_bits(isp, ISP1301_INTERRUPT_FALLING, ~0);
      isp1301_clear_bits(isp, ISP1301_INTERRUPT_RISING, ~0);

#ifdef      CONFIG_USB_OTG
      status = otg_bind(isp);
      if (status < 0) {
            dev_dbg(&i2c->dev, "can't bind OTG\n");
            goto fail2;
      }
#endif

      if (machine_is_omap_h2()) {
            /* full speed signaling by default */
            isp1301_set_bits(isp, ISP1301_MODE_CONTROL_1,
                  MC1_SPEED_REG);
            isp1301_set_bits(isp, ISP1301_MODE_CONTROL_2,
                  MC2_SPD_SUSP_CTRL);

            /* IRQ wired at M14 */
            omap_cfg_reg(M14_1510_GPIO2);
            isp->irq = OMAP_GPIO_IRQ(2);
            if (gpio_request(2, "isp1301") == 0)
                  gpio_direction_input(2);
            isp->irq_type = IRQF_TRIGGER_FALLING;
      }

      isp->irq_type |= IRQF_SAMPLE_RANDOM;
      status = request_irq(isp->irq, isp1301_irq,
                  isp->irq_type, DRIVER_NAME, isp);
      if (status < 0) {
            dev_dbg(&i2c->dev, "can't get IRQ %d, err %d\n",
                        isp->irq, status);
#ifdef      CONFIG_USB_OTG
fail2:
#endif
            i2c_detach_client(i2c);
            goto fail1;
      }

      isp->otg.dev = &isp->client.dev;
      isp->otg.label = DRIVER_NAME;

      isp->otg.set_host = isp1301_set_host,
      isp->otg.set_peripheral = isp1301_set_peripheral,
      isp->otg.set_power = isp1301_set_power,
      isp->otg.start_srp = isp1301_start_srp,
      isp->otg.start_hnp = isp1301_start_hnp,

      enable_vbus_draw(isp, 0);
      power_down(isp);
      the_transceiver = isp;

#ifdef      CONFIG_USB_OTG
      update_otg1(isp, isp1301_get_u8(isp, ISP1301_INTERRUPT_SOURCE));
      update_otg2(isp, isp1301_get_u8(isp, ISP1301_OTG_STATUS));
#endif

      dump_regs(isp, __FUNCTION__);

#ifdef      VERBOSE
      mod_timer(&isp->timer, jiffies + TIMER_JIFFIES);
      dev_dbg(&i2c->dev, "scheduled timer, %d min\n", TIMER_MINUTES);
#endif

      status = otg_set_transceiver(&isp->otg);
      if (status < 0)
            dev_err(&i2c->dev, "can't register transceiver, %d\n",
                  status);

      return 0;
}

static int isp1301_scan_bus(struct i2c_adapter *bus)
{
      if (!i2c_check_functionality(bus, I2C_FUNC_SMBUS_BYTE_DATA
                  | I2C_FUNC_SMBUS_READ_WORD_DATA))
            return -EINVAL;
      return i2c_probe(bus, &addr_data, isp1301_probe);
}

static struct i2c_driver isp1301_driver = {
      .driver = {
            .name = "isp1301_omap",
      },
      .attach_adapter   = isp1301_scan_bus,
      .detach_client    = isp1301_detach_client,
};

/*-------------------------------------------------------------------------*/

static int __init isp_init(void)
{
      return i2c_add_driver(&isp1301_driver);
}
module_init(isp_init);

static void __exit isp_exit(void)
{
      if (the_transceiver)
            otg_set_transceiver(0);
      i2c_del_driver(&isp1301_driver);
}
module_exit(isp_exit);


Generated by  Doxygen 1.6.0   Back to index