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6 commits

Author SHA1 Message Date
Michael Zaidman
db8d3a2127 HID: ft260: fix device removal due to USB disconnect
This commit fixes a functional regression introduced by the commit 82f09a637d
("HID: ft260: improve error handling of ft260_hid_feature_report_get()")
when upon USB disconnect, the FTDI FT260 i2c device is still available within
the /dev folder.

In my company's product, where the host USB to FT260 USB connection is
hard-wired in the PCB, the issue is not reproducible. To reproduce it, I used
the VirtualBox Ubuntu 20.04 VM and the UMFT260EV1A development module for the
FTDI FT260 chip:

Plug the UMFT260EV1A module into a USB port and attach it to VM.

The VM shows 2 i2c devices under the /dev:
    michael@michael-VirtualBox:~$ ls /dev/i2c-*
    /dev/i2c-0  /dev/i2c-1

The i2c-0 is not related to the FTDI FT260:
    michael@michael-VirtualBox:~$ cat /sys/bus/i2c/devices/i2c-0/name
    SMBus PIIX4 adapter at 4100

The i2c-1 is created by hid-ft260.ko:
    michael@michael-VirtualBox:~$ cat /sys/bus/i2c/devices/i2c-1/name
    FT260 usb-i2c bridge on hidraw1

Now, detach the FTDI FT260 USB device from VM. We expect the /dev/i2c-1
to disappear, but it's still here:
    michael@michael-VirtualBox:~$ ls /dev/i2c-*
    /dev/i2c-0  /dev/i2c-1

And the kernel log shows:
    [  +0.001202] usb 2-2: USB disconnect, device number 3
    [  +0.000109] ft260 0003:0403:6030.0002: failed to retrieve system status
    [  +0.000316] ft260 0003:0403:6030.0003: failed to retrieve system status

It happens because the commit 82f09a637d changed the ft260_get_system_config()
return logic. This caused the ft260_is_interface_enabled() to exit with error
upon the FT260 device USB disconnect, which in turn, aborted the ft260_remove()
before deleting the FT260 i2c device and cleaning its sysfs stuff.

This commit restores the FT260 USB removal functionality and improves the
ft260_is_interface_enabled() code to handle correctly all chip modes defined
by the device interface configuration pins DCNF0 and DCNF1.

Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Acked-by: Aaron Jones (FTDI-UK) <aaron.jones@ftdichip.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2021-07-29 12:38:32 +02:00
Michael Zaidman
9f59efcd51 HID: ft260: fix format type warning in ft260_word_show()
Fixes: 6a82582d9f ("HID: ft260: add usb hid to i2c host bridge driver")

Fix warning reported by static analysis when built with W=1 for arm64 by
clang version 13.0.0

>> drivers/hid/hid-ft260.c:794:44: warning: format specifies type 'short' but
   the argument has type 'int' [-Wformat]
           return scnprintf(buf, PAGE_SIZE, "%hi\n", le16_to_cpu(*field));
                                             ~~~     ^~~~~~~~~~~~~~~~~~~
                                             %i
   include/linux/byteorder/generic.h:91:21: note: expanded from
                                            macro 'le16_to_cpu'
   #define le16_to_cpu __le16_to_cpu
                       ^
   include/uapi/linux/byteorder/big_endian.h:36:26: note: expanded from
                                                    macro '__le16_to_cpu'
   #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x))
                            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/uapi/linux/swab.h:105:2: note: expanded from macro '__swab16'
           (__builtin_constant_p((__u16)(x)) ?     \
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Any sprintf style use of %h or %hi for a sub-int sized value isn't useful
since integer promotion is done on the value anyway. So, use %d instead.

https://lore.kernel.org/lkml/CAHk-=wgoxnmsj8GEVFJSvTwdnWm8wVJthefNk2n6+4TC=20e0Q@mail.gmail.com/

Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Suggested-by: Joe Perches <joe@perches.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2021-07-27 12:22:16 +02:00
Michael Zaidman
82f09a637d HID: ft260: improve error handling of ft260_hid_feature_report_get()
The ft260_hid_feature_report_get() checks if the return size matches the
requested size. But the function can also fail with at least -ENOMEM.  Add the
< 0 checks.

In ft260_hid_feature_report_get(), do not do the memcpy to the caller's buffer
if there is an error.

Fixes: 6a82582d9f ("HID: ft260: add usb hid to i2c host bridge driver")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2021-05-27 15:40:34 +02:00
Michael Zaidman
b45ef5db7b HID: ft260: check data size in ft260_smbus_write()
The SMbus block transaction limits the number of bytes transferred to 32,
but nothing prevents a user from specifying via ioctl a larger data size
than the ft260 can handle in a single transfer.

i2cdev_ioctl_smbus()
   --> i2c_smbus_xfer
       --> __i2c_smbus_xfer
           --> ft260_smbus_xfer
               --> ft260_smbus_write

This patch adds data size checking in the ft260_smbus_write().

Fixes: 98189a0adfa0 ("HID: ft260: add usb hid to i2c host bridge driver")
Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2021-05-05 14:32:46 +02:00
Dan Carpenter
2076b7bdc5 HID: ft260: fix an error message in ft260_i2c_write_read()
The "len" variable is uninitialize.

Fixes: 6a82582d9f ("HID: ft260: add usb hid to i2c host bridge driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2021-03-19 14:26:16 +01:00
Michael Zaidman
6a82582d9f HID: ft260: add usb hid to i2c host bridge driver
The FTDI FT260 chip implements USB to I2C/UART bridges through two
USB HID class interfaces. The first - for I2C, and the second for UART.
Each interface is independent, and the kernel detects it as a separate
USB hidraw device.

This commit adds I2C host adapter support.

Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Tested-by: Aaron Jones (FTDI-UK) <aaron.jones@ftdichip.com
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2021-03-16 08:22:54 +01:00