cp2112 supports single I2C read/write transactions. It can't combine I2C
transactions.
Add master_xfer, using similar code flow as for smbus_xfer.
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
CP2112 does not offer an atomic method to set both gpio
direction and value.
Also it does not permit to set gpio value before putting
gpio in output. In fact, accordingly to Silicon Labs
AN495, Rev. 0.2, cpt. 4.4, the HID report to set gpio
values "does not affect any pins that are not configured
as outputs".
This is confirmed on evaluation board CP2112-EK.
With current driver, after execute:
echo in > /sys/class/gpio/gpio248/direction
echo low > /sys/class/gpio/gpio248/direction
gpio output is still high. Only after a following
echo low > /sys/class/gpio/gpio248/direction
gpio output gets low.
Fix driver by changing order of operations; first set
direction then set value.
The drawback of this new sequence is that we can have
a pulse on gpio pin when direction is changed from
input to output-low, but this cannot be avoided on
current CP2112.
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
tests have shown that output reports use hid_hw_output_report().
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
hid_out_raw_report is going to be obsoleted as it is not part of the
unified HID low level transport documentation
(Documentation/hid/hid-transport.txt)
hid_output_raw_report(hdev, buf, sizeof(buf), HID_FEATURE_REPORT);
is strictly equivalent to:
hid_hw_raw_request(hdev, buf[0], buf, sizeof(buf),
HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
Then replace buf[0] by the appropriate define.
So use the new api.
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Both cp2112_read_req() and cp2112_write_req() are returning negative
value in cases of error, but cp2112_xfer() is storing the return
value into unsigned size_t-typed 'count'.
Fix this by making 'count' signed type.
Reported-by: fengguang.wu@intel.com
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Commit cafebc0 ("HID: remove hid_get_raw_report in struct hid_device")
obsoletes the use of hdev->hid_get_raw_report(), as calling
hid_hw_raw_request() is functionally equivalent.
Convert cp2112 to use this notation.
Reported-by: fengguang.wu@intel.com
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This patch adds support for the Silicon Labs CP2112 "Single-Chip HID USB to
SMBus Master Bridge."
This is a HID device driver which registers as an i2c adapter and gpiochip to
expose these functions of the CP2112. The customizable USB descriptor fields
are exposed as sysfs attributes. The SMBus byte-read, byte-data-read/write,
and word-data-read transfer modes have been tested by talking to an i2c
sensor. The GPIO functions and USB descriptor field programming have also
been tested.
Signed-off-by: David Barksdale <dbarksdale@uplogix.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
