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i2c_device_id are not supposed to change at runtime. All functions
working with i2c_device_id provided by <linux/i2c.h> work with
const i2c_device_id. So mark the non-const structs as const.
Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Since OF and ACPI case almost the same get rid of code duplication
by moving gpiod_get() calls directly to ->probe().
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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In order to make GPIO ACPI library stricter prepare users of
gpiod_get_index() to correctly behave when there no mapping is
provided by firmware.
Here we add explicit mapping between _CRS GpioIo() resources and
their names used in the driver.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Joe and Bjørn suggested that it'd be nicer to not have the
cast in the fairly common case of doing
*(u8 *)skb_put(skb, 1) = c;
Add skb_put_u8() for this case, and use it across the code,
using the following spatch:
@@
expression SKB, C, S;
typedef u8;
identifier fn = {skb_put};
fresh identifier fn2 = fn ## "_u8";
@@
- *(u8 *)fn(SKB, S) = C;
+ fn2(SKB, C);
Note that due to the "S", the spatch isn't perfect, it should
have checked that S is 1, but there's also places that use a
sizeof expression like sizeof(var) or sizeof(u8) etc. Turns
out that nobody ever did something like
*(u8 *)skb_put(skb, 2) = c;
which would be wrong anyway since the second byte wouldn't be
initialized.
Suggested-by: Joe Perches <joe@perches.com>
Suggested-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.
Make these functions return void * and remove all the casts across
the tree, adding a (u8 *) cast only where the unsigned char pointer
was used directly, all done with the following spatch:
@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)
@@
expression E, SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)
@@
expression SKB, LEN;
identifier fn = { skb_push, __skb_push, skb_push_rcsum };
@@
- fn(SKB, LEN)[0]
+ *(u8 *)fn(SKB, LEN)
Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.
Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:
@@
expression SKB, LEN;
typedef u8;
identifier fn = { skb_put, __skb_put };
@@
- *(fn(SKB, LEN))
+ *(u8 *)fn(SKB, LEN)
@@
expression E, SKB, LEN;
identifier fn = { skb_put, __skb_put };
type T;
@@
- E = ((T *)(fn(SKB, LEN)))
+ E = fn(SKB, LEN)
which actually doesn't cover pskb_put since there are only three
users overall.
A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.
An spatch similar to the one for skb_put_zero() converts many
of the places using it:
@@
identifier p, p2;
expression len, skb, data;
type t, t2;
@@
(
-p = skb_put(skb, len);
+p = skb_put_data(skb, data, len);
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-p = (t)skb_put(skb, len);
+p = skb_put_data(skb, data, len);
)
(
p2 = (t2)p;
-memcpy(p2, data, len);
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-memcpy(p, data, len);
)
@@
type t, t2;
identifier p, p2;
expression skb, data;
@@
t *p;
...
(
-p = skb_put(skb, sizeof(t));
+p = skb_put_data(skb, data, sizeof(t));
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-p = (t *)skb_put(skb, sizeof(t));
+p = skb_put_data(skb, data, sizeof(t));
)
(
p2 = (t2)p;
-memcpy(p2, data, sizeof(*p));
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-memcpy(p, data, sizeof(*p));
)
@@
expression skb, len, data;
@@
-memcpy(skb_put(skb, len), data, len);
+skb_put_data(skb, data, len);
(again, manually post-processed to retain some comments)
Reviewed-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Another place in the code that unveils non-tested at all ACPI case.
Use unified device property API in meaningful way.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Since we got rid of platform data, the driver may use GPIO descriptor
directly.
Looking deeply to the use of the GPIO pin it looks like it should be
a fixed voltage regulator rather than custom GPIO handling. But this
is out of scope of the change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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I2C framework followed by IRQ framework does set interrupt polarity
correctly if it's properly specified in firmware (ACPI or DT).
Get rid of the redundant trick when requesting interrupt.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Legacy platform data must go away. We are on the safe side here since
there are no users of it in the kernel.
If anyone by any odd reason needs it the GPIO lookup tables and
built-in device properties at your service.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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We return -ENODEV if ACPI provides a GPIO resource. Looks really wrong.
If it has even been tested?
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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drivers/nfc/st21nfca/i2c.c does not use any miscdevice, so this patch
remove this unnecessary inclusion.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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When st21nfca_hci_i2c_acpi_request_resources() gets called we
already know that the entries in ->acpi_match_table have matched
ACPI ID of the device.
In addition I2C client pointer cannot be NULL in any case
(otherwise I2C core would not call ->probe() for the driver in
the first place).
Drop the two useless checks from the driver.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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When they're present, set is_ese_present and set is_uicc_present
to the value describe in their package description.
So far is_ese_present and is_uicc_present was set to true if their
property was present.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Since
commit 10cf4899f8af ("gpiolib: tighten up ACPI legacy gpio lookups")
If _DSD properties are available in an ACPI node, we are not
allowed to fallback to _CRS data to retrieve gpio properties.
This was causing us to fail if uicc-present and/or ese-present
are defined.
To be consistent with devicetree change ST_NCI_GPIO_NAME_RESET
content to reset so that acpi_find_gpio in drivers/gpio/gpiolib.c
will look for reset-gpios. In the mean time the ACPI table needs
to be fixed as follow:
Device (NFC1)
{
Name (_ADR, Zero) // _ADR: Address
Name (_HID, "SMO2100") // _HID: Hardware ID
Name (_CID, "SMO2100") // _CID: Compatible ID
Name (_DDN, "SMO NFC") // _DDN: DOS Device Name
Name (_UID, One) // _UID: Unique ID
Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings
{
Name (SBUF, ResourceTemplate ()
{
I2cSerialBus (0x0008, ControllerInitiated, 400000,
AddressingMode7Bit, "\\_SB.I2C7",
0x00, ResourceConsumer, ,)
GpioInt (Edge, ActiveHigh, ExclusiveAndWake, PullNone, 0x0000,
"\\_SB.GPO2", 0x00, ResourceConsumer, ,)
{ // Pin list
0x0001
}
GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, IoRestrictionOutputOnly,
"\\_SB.GPO2", 0x00, ResourceConsumer, ,)
{ // Pin list
0x0002,
}
})
Name (_DSD, Package (0x02)
{
ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301") /* Device Properties for _DSD */,
Package (0x03)
{
Package (0x02) { "uicc-present", 1 },
Package (0x02) { "ese-present", 1 },
Package (0x02) { "enable-gpios", Package(0x04) { ^NFC1, 1, 0, 0} },
}
})
Return (SBUF) /* \_SB_.I2C7.NFC1._CRS.SBUF */
}
Method (_STA, 0, NotSerialized) // _STA: Status
{
Return (0x0F)
}
}
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Fix static checker warning:
drivers/nfc/st21nfca/i2c.c:530 st21nfca_hci_i2c_acpi_request_resources()
error: 'gpiod_ena' dereferencing possible ERR_PTR()
Fix so that if no enable gpio can be retrieved an -ENODEV is returned.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: dfa8070d7f64 ("nfc: st21nfca: Add support for acpi probing for i2c device.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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i2c_driver does not need to set an owner because i2c_register_driver()
will set it.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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A few code cleanups, mostly empty lines removal.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Add support for acpi probing.
SMO2100 is used for st21nfca
It has been tested with the following acpi node on Minnowboard Max:
Note: Remove uicc-present or ese-present Package if one them is not
supported.
Device (NFC1)
{
Name (_ADR, Zero) // _ADR: Address
Name (_HID, "SMO2100") // _HID: Hardware ID
Name (_CID, "SMO2100") // _CID: Compatible ID
Name (_DDN, "SMO NFC") // _DDN: DOS Device Name
Name (_UID, One) // _UID: Unique ID
Name (_DSD, Package (0x02)
{
/* Device Properties for _DSD */
ToUUID ("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"),
Package (0x02)
{
Package (0x02) { "uicc-present", 1 },
Package (0x02) { "ese-present", 1 }
}
})
Method (_CRS, 0, NotSerialized) // _CRS: Current Resource Settings
{
Name (SBUF, ResourceTemplate ()
{
I2cSerialBus (0x0001, ControllerInitiated, 400000,
AddressingMode7Bit, "\\_SB.I2C7",
0x00, ResourceConsumer, ,)
GpioInt (Edge, ActiveHigh, ExclusiveAndWake, PullNone, 0x0000,
"\\_SB.GPO2", 0x00, ResourceConsumer, ,)
{ // Pin list
0x0001
}
GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, IoRestrictionOutputOnly,
"\\_SB.GPO2", 0x00, ResourceConsumer, ,)
{ // Pin list
0x0002,
}
})
Return (SBUF) /* \_SB_.I2C7.NFC1._CRS.SBUF */
}
Method (_STA, 0, NotSerialized) // _STA: Status
{
Return (0x0F)
}
}
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Add macro definition for each gpio string for an easier code
maintenance.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Group device table at the same place in order to make the code
easier to read and parse.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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DT headers already define NOOP routines when CONFIG_OF is not
defined.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Add a minor code style fixes
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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st21nfca has 1 physical SWP line and can support up to 2 secure elements
(UICC & eSE) thanks to an external switch managed with a gpio.
The platform integrator needs to specify thanks to 2 initialization
properties, uicc-present and ese-present, if it is suppose to have uicc
and/or ese. Of course if the platform does not have an external switch,
only one kind of secure element can be supported. Those parameters are
under platform integrator responsibilities.
During initialization, the white_list will be set according to those
parameters.
The discovery_se function will assume a secure element is physically
present according to uicc-present and ese-present values and will add it
to the secure element list. On ese activation, the atr is retrieved to
calculate a command exchange timeout based on the first atr(TB) value.
The se_io will allow to transfer data over SWP. 2 kind of events may appear
after a data is sent over:
- ST21NFCA_EVT_TRANSMIT_DATA when receiving an apdu answer
- ST21NFCA_EVT_WTX_REQUEST when the secure element needs more time than
expected to compute a command. If this timeout expired, a first recovery
tentative consist to send a simple software reset proprietary command.
If this tentative still fail, a second recovery tentative consist to send
a hardware reset proprietary command.
This function is only relevant for eSE like secure element.
This patch also change the way a pipe is referenced. There can be
different pipe connected to the same gate with different host destination
(ex: CONNECTIVITY). In order to keep host information every pipe are
reference with a tuple (gate, host). In order to reduce changes, we are
keeping unchanged the way a gate is addressed on the Terminal Host.
However, this is working because we consider the apdu reader gate is only
present on the eSE slot also the connectivity gate cannot give a reliable
value; it will give the latest stored pipe value.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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memory' message
Remove unnecessary memory allocation message already shown by devm_kzalloc.
This remove a warning when running scripts/checkpatch.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Other drivers are following the following compatible string format for dts:
s/_/-/
Because some devices may still use the previous string, the new corrected
string is added to the of_device_id table.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Report error returned by devm_gpio_request_one or
st21nfca_hci_platform_init instead of -ENODEV.
Reported-by: Dmitry Torokhov <dtor@chromium.org>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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- phy->gpio_irq is never done out of the request resources.
- irq_of_parse_and_map is already done in the i2c core so client->irq is
already set when entering in st21nfca_hci_i2c_of_request_resources
- In case of static platform configuration client->irq can be set directly
- It simplifies the code a bit.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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When CONFIG_OF is define add of_st21nfca_i2c_match to
MODULE_DEVICE_TABLE.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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This is a specific implementation, <asm/unaligned.h> is the
multiplexer that has the arch-specific knowledge of which
of the implementations needs to be used, so include that.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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Remove a useless new line in nfc_err call.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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after declarations"
Fixing scripts/checkpatch.pl warning "Missing a blank line after declarations" in:
- st21nfca.c:
- check_presence after fwi variable declaration.
- get_frame_size after len variable declaration.
- st21nfca_hci_i2c_repack after "i, j, r, size" variable declaration.
- st21nfca_dep.c st21nfca_tx_work after skb pointer declaration.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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This simplifies the code a bit.
Acked-by: Christophe RICARD <christophe-h.ricard@st.com>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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The .owner member of struct device_driver is assigned THIS_MODULE twice.
Introduced by:
commit c44cb2edd01ca31471d9385f0895891b006ab904
("NFC: dts: st21nfca: Add device-tree (Open Firmware) support to st21nfca")
Acked-by: Christophe RICARD <christophe-h.ricard@st.com>
Signed-off-by: Emil Goode <emilgoode@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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A DEP_RES with a SUPERVISOR PDU can be up to 16 bytes long.
In order to avoid useless read during p2p, extend first read
sequence to 16 and reduce third sequence to 12 to keep same
total on the full sequence.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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A start of frame is 7E 00 not only 7E. Make sure the first read sequence is
starting with 7E 00.
For example: 7E FF FF FF FF is as a correct crc but it is a bad frame.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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In case no data are retrieve through i2c or one specific case is not handled.
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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Arvind Yadav
Andy Shevchenko
Johannes Berg
Corentin Labbe
Christophe Ricard
Krzysztof Kozlowski
Axel Lin
Emil Goode