linux-stable.git/drivers/i2c, branch v3.16.48

i2c: imx: Use correct function to write to register

2017-09-15T17:30:14+00:00

commit 6c782a5ea56a799658e213a78dc1455264938afa upstream.

The i2c-imx driver incorrectly uses readb()/writeb() to read and
write to the appropriate registers when performing a repeated start.
The appropriate imx_i2c_read_reg()/imx_i2c_write_reg() functions
should be used instead. Performing a repeated start results in
a kernel panic. The platform is imx.

Signed-off-by: Michail G Etairidis 
Fixes: ce1a78840ff7 ("i2c: imx: add DMA support for freescale i2c driver")
Fixes: 054b62d9f25c ("i2c: imx: fix the i2c bus hang issue when do repeat restart")
Acked-by: Fugang Duan 
Acked-by: Uwe Kleine-König 
Signed-off-by: Wolfram Sang 
[bwh: Backported to 3.16: drop changes in i2c_imx_dma_read()]
Signed-off-by: Ben Hutchings

i2c: ismt: fix wrong device address when unmap the data buffer

2017-09-15T17:30:11+00:00

commit 17e83549e199d89aace7788a9f11c108671eecf5 upstream.

Fix the following kernel bug:

kernel BUG at drivers/iommu/intel-iommu.c:3260!
invalid opcode: 0000 [#5] PREEMPT SMP
Hardware name: Intel Corp. Harcuvar/Server, BIOS HAVLCRB0.X64.0013.D39.1608311820 08/31/2016
task: ffff880175389950 ti: ffff880176bec000 task.ti: ffff880176bec000
RIP: 0010:[]  [] intel_unmap+0x25b/0x260
RSP: 0018:ffff880176bef5e8  EFLAGS: 00010296
RAX: 0000000000000024 RBX: ffff8800773c7c88 RCX: 000000000000ce04
RDX: 0000000080000000 RSI: 0000000000000000 RDI: 0000000000000009
RBP: ffff880176bef638 R08: 0000000000000010 R09: 0000000000000004
R10: ffff880175389c78 R11: 0000000000000a4f R12: ffff8800773c7868
R13: 00000000ffffac88 R14: ffff8800773c7818 R15: 0000000000000001
FS:  00007fef21258700(0000) GS:ffff88017b5c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000066d6d8 CR3: 000000007118c000 CR4: 00000000003406e0
Stack:
 00000000ffffac88 ffffffff8199867f ffff880176bef5f8 ffff880100000030
 ffff880176bef668 ffff8800773c7c88 ffff880178288098 ffff8800772c0010
 ffff8800773c7818 0000000000000001 ffff880176bef648 ffffffff8150a86e
Call Trace:
 [] ? printk+0x46/0x48
 [] intel_unmap_page+0xe/0x10
 [] ismt_access+0x27b/0x8fa [i2c_ismt]
 [] ? __pm_runtime_suspend+0xa0/0xa0
 [] ? pm_suspend_timer_fn+0x80/0x80
 [] ? __pm_runtime_suspend+0xa0/0xa0
 [] ? pm_suspend_timer_fn+0x80/0x80
 [] ? pci_bus_read_dev_vendor_id+0xf0/0xf0
 [] i2c_smbus_xfer+0xec/0x4b0
 [] ? vprintk_emit+0x345/0x530
 [] i2cdev_ioctl_smbus+0x12b/0x240 [i2c_dev]
 [] ? vprintk_default+0x29/0x40
 [] i2cdev_ioctl+0x63/0x1ec [i2c_dev]
 [] do_vfs_ioctl+0x328/0x5d0
 [] ? vfs_write+0x11c/0x190
 [] ? rt_up_read+0x19/0x20
 [] SyS_ioctl+0x81/0xa0
 [] system_call_fastpath+0x16/0x6e

This happen When run "i2cdetect -y 0" detect SMBus iSMT adapter.

After finished I2C block read/write, when unmap the data buffer,
a wrong device address was pass to dma_unmap_single().

To fix this, give dma_unmap_single() the "dev" parameter, just like
what dma_map_single() does, then unmap can find the right devices.

Fixes: 13f35ac14cd0 ("i2c: Adding support for Intel iSMT SMBus 2.0 host controller")
Signed-off-by: Liwei Song 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Wolfram Sang 
Signed-off-by: Ben Hutchings

i2c: i2c-tiny-usb: fix buffer not being DMA capable

2017-09-15T17:29:48+00:00

commit 5165da5923d6c7df6f2927b0113b2e4d9288661e upstream.

Since v4.9 i2c-tiny-usb generates the below call trace
and longer works, since it can't communicate with the
USB device. The reason is, that since v4.9 the USB
stack checks, that the buffer it should transfer is DMA
capable. This was a requirement since v2.2 days, but it
usually worked nevertheless.

[   17.504959] ------------[ cut here ]------------
[   17.505488] WARNING: CPU: 0 PID: 93 at drivers/usb/core/hcd.c:1587 usb_hcd_map_urb_for_dma+0x37c/0x570
[   17.506545] transfer buffer not dma capable
[   17.507022] Modules linked in:
[   17.507370] CPU: 0 PID: 93 Comm: i2cdetect Not tainted 4.11.0-rc8+ #10
[   17.508103] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
[   17.509039] Call Trace:
[   17.509320]  ? dump_stack+0x5c/0x78
[   17.509714]  ? __warn+0xbe/0xe0
[   17.510073]  ? warn_slowpath_fmt+0x5a/0x80
[   17.510532]  ? nommu_map_sg+0xb0/0xb0
[   17.510949]  ? usb_hcd_map_urb_for_dma+0x37c/0x570
[   17.511482]  ? usb_hcd_submit_urb+0x336/0xab0
[   17.511976]  ? wait_for_completion_timeout+0x12f/0x1a0
[   17.512549]  ? wait_for_completion_timeout+0x65/0x1a0
[   17.513125]  ? usb_start_wait_urb+0x65/0x160
[   17.513604]  ? usb_control_msg+0xdc/0x130
[   17.514061]  ? usb_xfer+0xa4/0x2a0
[   17.514445]  ? __i2c_transfer+0x108/0x3c0
[   17.514899]  ? i2c_transfer+0x57/0xb0
[   17.515310]  ? i2c_smbus_xfer_emulated+0x12f/0x590
[   17.515851]  ? _raw_spin_unlock_irqrestore+0x11/0x20
[   17.516408]  ? i2c_smbus_xfer+0x125/0x330
[   17.516876]  ? i2c_smbus_xfer+0x125/0x330
[   17.517329]  ? i2cdev_ioctl_smbus+0x1c1/0x2b0
[   17.517824]  ? i2cdev_ioctl+0x75/0x1c0
[   17.518248]  ? do_vfs_ioctl+0x9f/0x600
[   17.518671]  ? vfs_write+0x144/0x190
[   17.519078]  ? SyS_ioctl+0x74/0x80
[   17.519463]  ? entry_SYSCALL_64_fastpath+0x1e/0xad
[   17.519959] ---[ end trace d047c04982f5ac50 ]---

Signed-off-by: Sebastian Reichel 
Reviewed-by: Greg Kroah-Hartman 
Acked-by: Till Harbaum 
Signed-off-by: Wolfram Sang 
Signed-off-by: Ben Hutchings

i2c: riic: correctly finish transfers

2017-06-05T20:17:06+00:00

commit 71ccea095ea1d4efd004dab971be6d599e06fc3f upstream.

This fixes the condition where the controller has not fully completed its
final transfer and leaves the bus and controller in a undesirable state.

At the end of the last transmitted byte, the existing driver would just
signal for a STOP condition to be transmitted then immediately signal
completion. However, the full STOP procedure might not have fully taken
place by the time the runtime PM shuts off the peripheral clock, leaving
the bus in a suspended state.

Alternatively, the STOP condition on the bus may have completed, but when
the next transaction is requested by the upper layer, not all the
necessary register cleanup was finished from the last transfer which made
the driver return BUS BUSY when it really wasn't.

This patch now makes all transmit and receive transactions wait for the
STOP condition to fully complete before signaling a completed transaction.
With this new method, runtime PM no longer seems to be an issue.

Fixes: 310c18a41450 ("i2c: riic: add driver")
Signed-off-by: Chris Brandt 
Reviewed-by: Wolfram Sang 
Signed-off-by: Wolfram Sang 
Signed-off-by: Ben Hutchings

i2c: fix kernel memory disclosure in dev interface

2017-03-16T02:26:58+00:00

commit 30f939feaeee23e21391cfc7b484f012eb189c3c upstream.

i2c_smbus_xfer() does not always fill an entire block, allowing
kernel stack memory disclosure through the temp variable. Clear
it before it's read to.

Signed-off-by: Vlad Tsyrklevich 
Signed-off-by: Wolfram Sang 
Signed-off-by: Ben Hutchings

i2c: mux: pca954x: fix i2c mux selection caching

2017-03-16T02:26:38+00:00

commit 7f638c1cb0a1112dbe0b682a42db30521646686b upstream.

smbus functions return -ve on error, 0 on success.  However,
__i2c_transfer() have a different return signature - -ve on error, or
number of buffers transferred (which may be zero or greater.)

The upshot of this is that the sense of the test is reversed when using
the mux on a bus supporting the master_xfer method: we cache the value
and never retry if we fail to transfer any buffers, but if we succeed,
we clear the cached value.

Fix this by making pca954x_reg_write() return a negative error code for
all failure cases.

Fixes: 463e8f845cbf ("i2c: mux: pca954x: retry updating the mux selection on failure")
Acked-by: Peter Rosin 
Signed-off-by: Russell King 
Signed-off-by: Wolfram Sang 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

i2c: core: fix NULL pointer dereference under race condition

2017-02-23T03:54:29+00:00

commit 147b36d5b70c083cc76770c47d60b347e8eaf231 upstream.

Race condition between registering an I2C device driver and
deregistering an I2C adapter device which is assumed to manage that
I2C device may lead to a NULL pointer dereference due to the
uninitialized list head of driver clients.

The root cause of the issue is that the I2C bus may know about the
registered device driver and thus it is matched by bus_for_each_drv(),
but the list of clients is not initialized and commonly it is NULL,
because I2C device drivers define struct i2c_driver as static and
clients field is expected to be initialized by I2C core:

  i2c_register_driver()             i2c_del_adapter()
    driver_register()                 ...
      bus_add_driver()                ...
        ...                           bus_for_each_drv(..., __process_removed_adapter)
      ...                               i2c_do_del_adapter()
    ...                                   list_for_each_entry_safe(..., &driver->clients, ...)
    INIT_LIST_HEAD(&driver->clients);

To solve the problem it is sufficient to do clients list head
initialization before calling driver_register().

The problem was found while using an I2C device driver with a sluggish
registration routine on a bus provided by a physically detachable I2C
master controller, but practically the oops may be reproduced under
the race between arbitraty I2C device driver registration and managing
I2C bus device removal e.g. by unbinding the latter over sysfs:

% echo 21a4000.i2c > /sys/bus/platform/drivers/imx-i2c/unbind
  Unable to handle kernel NULL pointer dereference at virtual address 00000000
  Internal error: Oops: 17 [#1] SMP ARM
  CPU: 2 PID: 533 Comm: sh Not tainted 4.9.0-rc3+ #61
  Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
  task: e5ada400 task.stack: e4936000
  PC is at i2c_do_del_adapter+0x20/0xcc
  LR is at __process_removed_adapter+0x14/0x1c
  Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
  Control: 10c5387d  Table: 35bd004a  DAC: 00000051
  Process sh (pid: 533, stack limit = 0xe4936210)
  Stack: (0xe4937d28 to 0xe4938000)
  Backtrace:
  [] (i2c_do_del_adapter) from [] (__process_removed_adapter+0x14/0x1c)
  [] (__process_removed_adapter) from [] (bus_for_each_drv+0x6c/0xa0)
  [] (bus_for_each_drv) from [] (i2c_del_adapter+0xbc/0x284)
  [] (i2c_del_adapter) from [] (i2c_imx_remove+0x44/0x164 [i2c_imx])
  [] (i2c_imx_remove [i2c_imx]) from [] (platform_drv_remove+0x2c/0x44)
  [] (platform_drv_remove) from [] (__device_release_driver+0x90/0x12c)
  [] (__device_release_driver) from [] (device_release_driver+0x28/0x34)
  [] (device_release_driver) from [] (unbind_store+0x80/0x104)
  [] (unbind_store) from [] (drv_attr_store+0x28/0x34)
  [] (drv_attr_store) from [] (sysfs_kf_write+0x50/0x54)
  [] (sysfs_kf_write) from [] (kernfs_fop_write+0x100/0x214)
  [] (kernfs_fop_write) from [] (__vfs_write+0x34/0x120)
  [] (__vfs_write) from [] (vfs_write+0xa8/0x170)
  [] (vfs_write) from [] (SyS_write+0x4c/0xa8)
  [] (SyS_write) from [] (ret_fast_syscall+0x0/0x1c)

Signed-off-by: Vladimir Zapolskiy 
Signed-off-by: Wolfram Sang 
Signed-off-by: Ben Hutchings

i2c: qup: skip qup_i2c_suspend if the device is already runtime suspended

2016-11-20T01:17:34+00:00

commit 331dcf421c34d227784d07943eb01e4023a42b0a upstream.

If the i2c device is already runtime suspended, if qup_i2c_suspend is
executed during suspend-to-idle or suspend-to-ram it will result in the
following splat:

WARNING: CPU: 3 PID: 1593 at drivers/clk/clk.c:476 clk_core_unprepare+0x80/0x90
Modules linked in:

CPU: 3 PID: 1593 Comm: bash Tainted: G        W       4.8.0-rc3 #14
Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
PC is at clk_core_unprepare+0x80/0x90
LR is at clk_unprepare+0x28/0x40
pc : [] lr : [] pstate: 60000145
Call trace:
 clk_core_unprepare+0x80/0x90
 qup_i2c_disable_clocks+0x2c/0x68
 qup_i2c_suspend+0x10/0x20
 platform_pm_suspend+0x24/0x68
 ...

This patch fixes the issue by executing qup_i2c_pm_suspend_runtime
conditionally in qup_i2c_suspend.

Signed-off-by: Sudeep Holla 
Reviewed-by: Andy Gross 
Signed-off-by: Wolfram Sang 
Signed-off-by: Ben Hutchings

i2c: mux: pca954x: retry updating the mux selection on failure

2016-11-20T01:17:34+00:00

commit 463e8f845cbf1c01e4cc8aeef1703212991d8e1e upstream.

The cached value of the last selected channel prevents retries on the
next call, even on failure to update the selected channel. Fix that.

Signed-off-by: Peter Rosin 
Signed-off-by: Wolfram Sang 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

i2c-eg20t: fix race between i2c init and interrupt enable

2016-11-20T01:17:33+00:00

commit 371a015344b6e270e7e3632107d9554ec6d27a6b upstream.

the eg20t driver call request_irq() function before the pch_base_address,
base address of i2c controller's register, is assigned an effective value.

there is one possible scenario that an interrupt which isn't inside eg20t
arrives immediately after request_irq() is executed when i2c controller
shares an interrupt number with others. since the interrupt handler
pch_i2c_handler() has already active as shared action, it will be called
and read its own register to determine if this interrupt is from itself.

At that moment, since base address of i2c registers is not remapped
in kernel space yet,so the INT handler will access an illegal address
and then a error occurs.

Signed-off-by: Yadi.hu 
Signed-off-by: Wolfram Sang 
Signed-off-by: Ben Hutchings