Commit graph

11 commits

Author SHA1 Message Date
Christophe Ricard c44cb2edd0 NFC: dts: st21nfca: Add device-tree (Open Firmware) support to st21nfca
Add functions to recover hardware resources from the device-tree
when not provided by the platform data.

Based on pn544 devicetree implementation

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-05-20 00:47:43 +02:00
Christophe Ricard 0c942b007b NFC: st21nfca: Free buffer when a bad frame is detected
When a bad frame is detected for a bad crc.
We were reallocating and loosing the previous frame pointer.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-05-05 01:04:10 +02:00
Christophe Ricard a3c5d8fb7f NFC: st21nfca: Synchronize i2c Tx and Rx path
Stabilize communication by using a mutex.
This avoids running a write transaction during a read retry or a read
transaction during a write retry.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-05-05 01:01:23 +02:00
Christophe Ricard c97ffdbf51 NFC: st21nfca: Improved i2c Rx data correctness check
A frame starts with ST21NFCA_SOF_EOF(0x7e) + 0x00.
A frame ends with ST21NFCA_SOF_EOF(0x7e).
It is possible that the i2c macrocell is stopped for other
communication interfaces with highest priority(RF or SWP).
This can be seen with some 0xFF data at the end of a received shdlc buffer.
If this happen we need to discard the frame because the CLF will repeat it.

In order to push accurate data to hci layer, we add the following fix:
- Instead of looking for the first 0x7e in the frame, check that the last
received byte is 0x7e.
- Check that the first frame reception block start with start of
frame(0x7e 0x00). If not, clear the buffer.
- Check that the next frame reception block do not start with start of
frame(0x7e). If so, clear the buffer.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-05-05 01:00:34 +02:00
Christophe Ricard e1fb97b925 NFC: st21nfca: Fix st21nfca_hci_remove_len_crc tail room handling
There is no byte stuffing when data are stored in skb.
TAILROOM is 2 byte crc + 1 byte eof.

st21nfca_hci_remove_len_crc was doing an incorrect operation on
the TAILROOM data.
If shdlc timer T2 is triggered, it will request to send the same data.
Before every hci data was lost after st21nfca_hci_remove_len_crc.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-05-05 00:15:26 +02:00
Christophe Ricard 3096e25a3e NFC: st21nfca: Fix incorrect byte stuffing revocation
Byte stuffing was not correctly removed after a i2c read operation.
This was causing improper crc calculation when byte stuffing was
applied to more than 1 byte.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-05-05 00:06:27 +02:00
Christophe Ricard 18d2c624f9 NFC: st21nfca: Improve st21nfca initialization by handling reboot properly
Change in st21nfca_hci_platform_init in order to handle in a better way the
internal reboot command.
Once the reboot is completed, the driver expect to receive a 0x7e filled
buffer.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-04-22 00:37:30 +02:00
Christophe Ricard fcb45e6ab3 NFC: st21nfca: Reworked st21nfca_request_resources
Remove struct st21nfca_i2c_phy* as this parameter can be retrieve
through i2c_get_clientdata(client)

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-04-22 00:37:30 +02:00
Christophe Ricard 9bac75d0ec NFC: st21nfca: st21nfca_hci_i2c_probe returns st21nfca_hci_probe result.
st21nfca_hci_probe return 0 in case of successful call and a different
value in any other cases.

There is no need to check for st21nfca_hci_probe return as this will be
checked after st21nfca_hci_i2c_probe is completed.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-04-22 00:37:30 +02:00
Christophe Ricard c5b0c370fc NFC: st21nfca: Remove sporadic wait_tab variable from functions.
wait_tab variable is already global and may create conflicts.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-04-22 00:37:29 +02:00
Christophe Ricard 68957303f4 NFC: ST21NFCA: Add driver for STMicroelectronics ST21NFCA NFC Chip
Add driver for STMicroelectronics ST21NFCA NFC controller.
ST21NFCA is using HCI protocol, shdlc as LLC layer & I2C as
communication protocol.

Adding support for Reader/Writer mode with Tag type 1/2/3/4 A & B.
It is using proprietary gate 15 for ISO14443-3 such as type 1 &
type 2 tags. It is using proprietary gate 14 for type F tags.
ST21NFCA_DEVICE_MGNT_GATE gives access to proprietary CLF configuration.
Standard gate for ISO14443-4 A (13) & B (11) are also used.

ST21NFCA specific mecanism:

One particular point to notice for the data handling is that frame
does not contain any length value. Therefore the i2c part of this driver
is managing the reception with a read length sequence until the end of
frame (0x7e) is reached.

In order to avoid conflict between sof & eof a mecanism
called byte stuffing concist of an escape byte (0x7d) insertion before
special byte (0x7e, 0x7d). The special byte is then xored with 0x20.

In this driver, When data are available in the CLF, the interrupt
gpio is driven to active state and triggered an interrupt.
Once the i2c_master_recv start, the interrupt gpio is driven to idle
state until its complete. If the frame is incomplete or data are still
available, interrupts will be triggered again.

Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2014-04-22 00:37:25 +02:00