As per the SAF1761 data sheet[0], the DcChipID register represents
the hardware version number (0001h) and the chip ID (1582h) for the
Peripheral Controller.

However as per the ISP1761 data sheet[1], the DcChipID register
represents the hardware version number (0015h) and the chip ID (8210h)
for the Peripheral Controller.

This patch adds support for both the chip ID values.

[0] http://www.nxp.com/documents/data_sheet/SAF1761.pdf
[1] http://pdf.datasheetcatalog.com/datasheets2/74/742102_1.pdfAcked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The IRQF_DISABLED is a NOOP and scheduled to be removed.  According to
commit e58aa3d2 ("genirq: Run irq handlers with interrupts
disabled") running IRQ handlers with interrupts enabled can cause stack
overflows when the interrupt line of the issuing device is still active.

This patch removes using this deprecated flag and additionally removes
redundantly setting IRQF_SHARED for isp1760_udc_register().
Signed-off-by: NValentin Rothberg <Valentin.Rothberg@lip6.fr>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Use spin_{un,}lock_irq{save,restore} in isp1760_udc_{start,stop} to
prevent following potentially deadlock scenario between
isp1760_udc_{start,stop} and isp1760_udc_irq :

=================================
[ INFO: inconsistent lock state ]
4.0.0-rc2-00004-gf7bb2ef60173 #51 Not tainted
---------------------------------
inconsistent {HARDIRQ-ON-W} -> {IN-HARDIRQ-W} usage.
in:imklog/2118 [HC1[1]:SC0[0]:HE0:SE1] takes:
 (&(&udc->lock)->rlock){?.+...}, at: [<c0397a93>] isp1760_udc_irq+0x367/0x9dc
{HARDIRQ-ON-W} state was registered at:
  [<c05135b3>] _raw_spin_lock+0x23/0x30
  [<c0396b87>] isp1760_udc_start+0x23/0xf8
  [<c039dc21>] udc_bind_to_driver+0x71/0xb0
  [<c039de4f>] usb_gadget_probe_driver+0x53/0x9c
  [<bf80d0df>] usb_composite_probe+0x8a/0xa4 [libcomposite]
  [<bf8311a7>] 0xbf8311a7
  [<c00088c5>] do_one_initcall+0x8d/0x17c
  [<c050b92d>] do_init_module+0x49/0x148
  [<c0087323>] load_module+0xb7f/0xbc4
  [<c0087471>] SyS_finit_module+0x51/0x74
  [<c000d8c1>] ret_fast_syscall+0x1/0x68
irq event stamp: 4966
hardirqs last  enabled at (4965): [<c05137df>] _raw_spin_unlock_irq+0x1f/0x24
hardirqs last disabled at (4966): [<c00110b3>] __irq_svc+0x33/0x64
softirqs last  enabled at (4458): [<c0023475>] __do_softirq+0x23d/0x2d0
softirqs last disabled at (4389): [<c002380b>] irq_exit+0xef/0x15c

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&(&udc->lock)->rlock);
  <Interrupt>
    lock(&(&udc->lock)->rlock);

 *** DEADLOCK ***

1 lock held by in:imklog/2118:
 #0:  (&f->f_pos_lock){+.+.+.}, at: [<c010a101>] __fdget_pos+0x31/0x34
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The isp1760 driver registration function returns an error if USB is
disabled. This made sense when the driver only supported host
controllers, but now that it supports peripheral controllers host
support isn't mandatory anymore.

Fix this by returning an error only when both the HCD and UDC functions
are disabled, either through the kernel configuration or at runtime.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

Now that this is DRD, it doesn't make sense to keep it under
drivers/usb/host.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>

The ISP1761 is a dual-mode host and device controller backward
compatible on the host side with the ISP1760. Add support for the device
controller.
Signed-off-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NFelipe Balbi <balbi@ti.com>