mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 18:09:57 +00:00
![Colin Ian King](/assets/img/avatar_default.png)
The return statement is indented incorrectly, add in a missing tab and remove an extraneous space after the return Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net>
1265 lines
32 KiB
C
1265 lines
32 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* --------------------------------------------------------------------
|
|
* Driver for ST NFC Transceiver ST95HF
|
|
* --------------------------------------------------------------------
|
|
* Copyright (C) 2015 STMicroelectronics Pvt. Ltd. All rights reserved.
|
|
*/
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/gpio.h>
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/module.h>
|
|
#include <linux/netdevice.h>
|
|
#include <linux/nfc.h>
|
|
#include <linux/of_gpio.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_irq.h>
|
|
#include <linux/property.h>
|
|
#include <linux/regulator/consumer.h>
|
|
#include <linux/wait.h>
|
|
#include <net/nfc/digital.h>
|
|
#include <net/nfc/nfc.h>
|
|
|
|
#include "spi.h"
|
|
|
|
/* supported protocols */
|
|
#define ST95HF_SUPPORTED_PROT (NFC_PROTO_ISO14443_MASK | \
|
|
NFC_PROTO_ISO14443_B_MASK | \
|
|
NFC_PROTO_ISO15693_MASK)
|
|
/* driver capabilities */
|
|
#define ST95HF_CAPABILITIES NFC_DIGITAL_DRV_CAPS_IN_CRC
|
|
|
|
/* Command Send Interface */
|
|
/* ST95HF_COMMAND_SEND CMD Ids */
|
|
#define ECHO_CMD 0x55
|
|
#define WRITE_REGISTER_CMD 0x9
|
|
#define PROTOCOL_SELECT_CMD 0x2
|
|
#define SEND_RECEIVE_CMD 0x4
|
|
|
|
/* Select protocol codes */
|
|
#define ISO15693_PROTOCOL_CODE 0x1
|
|
#define ISO14443A_PROTOCOL_CODE 0x2
|
|
#define ISO14443B_PROTOCOL_CODE 0x3
|
|
|
|
/*
|
|
* head room len is 3
|
|
* 1 byte for control byte
|
|
* 1 byte for cmd
|
|
* 1 byte for size
|
|
*/
|
|
#define ST95HF_HEADROOM_LEN 3
|
|
|
|
/*
|
|
* tailroom is 1 for ISO14443A
|
|
* and 0 for ISO14443B/ISO15693,
|
|
* hence the max value 1 should be
|
|
* taken.
|
|
*/
|
|
#define ST95HF_TAILROOM_LEN 1
|
|
|
|
/* Command Response interface */
|
|
#define MAX_RESPONSE_BUFFER_SIZE 280
|
|
#define ECHORESPONSE 0x55
|
|
#define ST95HF_ERR_MASK 0xF
|
|
#define ST95HF_TIMEOUT_ERROR 0x87
|
|
#define ST95HF_NFCA_CRC_ERR_MASK 0x20
|
|
#define ST95HF_NFCB_CRC_ERR_MASK 0x01
|
|
|
|
/* ST95HF transmission flag values */
|
|
#define TRFLAG_NFCA_SHORT_FRAME 0x07
|
|
#define TRFLAG_NFCA_STD_FRAME 0x08
|
|
#define TRFLAG_NFCA_STD_FRAME_CRC 0x28
|
|
|
|
/* Misc defs */
|
|
#define HIGH 1
|
|
#define LOW 0
|
|
#define ISO14443A_RATS_REQ 0xE0
|
|
#define RATS_TB1_PRESENT_MASK 0x20
|
|
#define RATS_TA1_PRESENT_MASK 0x10
|
|
#define TB1_FWI_MASK 0xF0
|
|
#define WTX_REQ_FROM_TAG 0xF2
|
|
|
|
#define MAX_CMD_LEN 0x7
|
|
|
|
#define MAX_CMD_PARAMS 4
|
|
struct cmd {
|
|
int cmd_len;
|
|
unsigned char cmd_id;
|
|
unsigned char no_cmd_params;
|
|
unsigned char cmd_params[MAX_CMD_PARAMS];
|
|
enum req_type req;
|
|
};
|
|
|
|
struct param_list {
|
|
int param_offset;
|
|
int new_param_val;
|
|
};
|
|
|
|
/*
|
|
* List of top-level cmds to be used internally by the driver.
|
|
* All these commands are build on top of ST95HF basic commands
|
|
* such as SEND_RECEIVE_CMD, PROTOCOL_SELECT_CMD, etc.
|
|
* These top level cmds are used internally while implementing various ops of
|
|
* digital layer/driver probe or extending the digital framework layer for
|
|
* features that are not yet implemented there, for example, WTX cmd handling.
|
|
*/
|
|
enum st95hf_cmd_list {
|
|
CMD_ECHO,
|
|
CMD_ISO14443A_CONFIG,
|
|
CMD_ISO14443A_DEMOGAIN,
|
|
CMD_ISO14443B_DEMOGAIN,
|
|
CMD_ISO14443A_PROTOCOL_SELECT,
|
|
CMD_ISO14443B_PROTOCOL_SELECT,
|
|
CMD_WTX_RESPONSE,
|
|
CMD_FIELD_OFF,
|
|
CMD_ISO15693_PROTOCOL_SELECT,
|
|
};
|
|
|
|
static const struct cmd cmd_array[] = {
|
|
[CMD_ECHO] = {
|
|
.cmd_len = 0x2,
|
|
.cmd_id = ECHO_CMD,
|
|
.no_cmd_params = 0,
|
|
.req = SYNC,
|
|
},
|
|
[CMD_ISO14443A_CONFIG] = {
|
|
.cmd_len = 0x7,
|
|
.cmd_id = WRITE_REGISTER_CMD,
|
|
.no_cmd_params = 0x4,
|
|
.cmd_params = {0x3A, 0x00, 0x5A, 0x04},
|
|
.req = SYNC,
|
|
},
|
|
[CMD_ISO14443A_DEMOGAIN] = {
|
|
.cmd_len = 0x7,
|
|
.cmd_id = WRITE_REGISTER_CMD,
|
|
.no_cmd_params = 0x4,
|
|
.cmd_params = {0x68, 0x01, 0x01, 0xDF},
|
|
.req = SYNC,
|
|
},
|
|
[CMD_ISO14443B_DEMOGAIN] = {
|
|
.cmd_len = 0x7,
|
|
.cmd_id = WRITE_REGISTER_CMD,
|
|
.no_cmd_params = 0x4,
|
|
.cmd_params = {0x68, 0x01, 0x01, 0x51},
|
|
.req = SYNC,
|
|
},
|
|
[CMD_ISO14443A_PROTOCOL_SELECT] = {
|
|
.cmd_len = 0x7,
|
|
.cmd_id = PROTOCOL_SELECT_CMD,
|
|
.no_cmd_params = 0x4,
|
|
.cmd_params = {ISO14443A_PROTOCOL_CODE, 0x00, 0x01, 0xA0},
|
|
.req = SYNC,
|
|
},
|
|
[CMD_ISO14443B_PROTOCOL_SELECT] = {
|
|
.cmd_len = 0x7,
|
|
.cmd_id = PROTOCOL_SELECT_CMD,
|
|
.no_cmd_params = 0x4,
|
|
.cmd_params = {ISO14443B_PROTOCOL_CODE, 0x01, 0x03, 0xFF},
|
|
.req = SYNC,
|
|
},
|
|
[CMD_WTX_RESPONSE] = {
|
|
.cmd_len = 0x6,
|
|
.cmd_id = SEND_RECEIVE_CMD,
|
|
.no_cmd_params = 0x3,
|
|
.cmd_params = {0xF2, 0x00, TRFLAG_NFCA_STD_FRAME_CRC},
|
|
.req = ASYNC,
|
|
},
|
|
[CMD_FIELD_OFF] = {
|
|
.cmd_len = 0x5,
|
|
.cmd_id = PROTOCOL_SELECT_CMD,
|
|
.no_cmd_params = 0x2,
|
|
.cmd_params = {0x0, 0x0},
|
|
.req = SYNC,
|
|
},
|
|
[CMD_ISO15693_PROTOCOL_SELECT] = {
|
|
.cmd_len = 0x5,
|
|
.cmd_id = PROTOCOL_SELECT_CMD,
|
|
.no_cmd_params = 0x2,
|
|
.cmd_params = {ISO15693_PROTOCOL_CODE, 0x0D},
|
|
.req = SYNC,
|
|
},
|
|
};
|
|
|
|
/* st95_digital_cmd_complete_arg stores client context */
|
|
struct st95_digital_cmd_complete_arg {
|
|
struct sk_buff *skb_resp;
|
|
nfc_digital_cmd_complete_t complete_cb;
|
|
void *cb_usrarg;
|
|
bool rats;
|
|
};
|
|
|
|
/*
|
|
* structure containing ST95HF driver specific data.
|
|
* @spicontext: structure containing information required
|
|
* for spi communication between st95hf and host.
|
|
* @ddev: nfc digital device object.
|
|
* @nfcdev: nfc device object.
|
|
* @enable_gpio: gpio used to enable st95hf transceiver.
|
|
* @complete_cb_arg: structure to store various context information
|
|
* that is passed from nfc requesting thread to the threaded ISR.
|
|
* @st95hf_supply: regulator "consumer" for NFC device.
|
|
* @sendrcv_trflag: last byte of frame send by sendrecv command
|
|
* of st95hf. This byte contains transmission flag info.
|
|
* @exchange_lock: semaphore used for signaling the st95hf_remove
|
|
* function that the last outstanding async nfc request is finished.
|
|
* @rm_lock: mutex for ensuring safe access of nfc digital object
|
|
* from threaded ISR. Usage of this mutex avoids any race between
|
|
* deletion of the object from st95hf_remove() and its access from
|
|
* the threaded ISR.
|
|
* @nfcdev_free: flag to have the state of nfc device object.
|
|
* [alive | died]
|
|
* @current_protocol: current nfc protocol.
|
|
* @current_rf_tech: current rf technology.
|
|
* @fwi: frame waiting index, received in reply of RATS according to
|
|
* digital protocol.
|
|
*/
|
|
struct st95hf_context {
|
|
struct st95hf_spi_context spicontext;
|
|
struct nfc_digital_dev *ddev;
|
|
struct nfc_dev *nfcdev;
|
|
unsigned int enable_gpio;
|
|
struct st95_digital_cmd_complete_arg complete_cb_arg;
|
|
struct regulator *st95hf_supply;
|
|
unsigned char sendrcv_trflag;
|
|
struct semaphore exchange_lock;
|
|
struct mutex rm_lock;
|
|
bool nfcdev_free;
|
|
u8 current_protocol;
|
|
u8 current_rf_tech;
|
|
int fwi;
|
|
};
|
|
|
|
/*
|
|
* st95hf_send_recv_cmd() is for sending commands to ST95HF
|
|
* that are described in the cmd_array[]. It can optionally
|
|
* receive the response if the cmd request is of type
|
|
* SYNC. For that to happen caller must pass true to recv_res.
|
|
* For ASYNC request, recv_res is ignored and the
|
|
* function will never try to receive the response on behalf
|
|
* of the caller.
|
|
*/
|
|
static int st95hf_send_recv_cmd(struct st95hf_context *st95context,
|
|
enum st95hf_cmd_list cmd,
|
|
int no_modif,
|
|
struct param_list *list_array,
|
|
bool recv_res)
|
|
{
|
|
unsigned char spi_cmd_buffer[MAX_CMD_LEN];
|
|
int i, ret;
|
|
struct device *dev = &st95context->spicontext.spidev->dev;
|
|
|
|
if (cmd_array[cmd].cmd_len > MAX_CMD_LEN)
|
|
return -EINVAL;
|
|
if (cmd_array[cmd].no_cmd_params < no_modif)
|
|
return -EINVAL;
|
|
if (no_modif && !list_array)
|
|
return -EINVAL;
|
|
|
|
spi_cmd_buffer[0] = ST95HF_COMMAND_SEND;
|
|
spi_cmd_buffer[1] = cmd_array[cmd].cmd_id;
|
|
spi_cmd_buffer[2] = cmd_array[cmd].no_cmd_params;
|
|
|
|
memcpy(&spi_cmd_buffer[3], cmd_array[cmd].cmd_params,
|
|
spi_cmd_buffer[2]);
|
|
|
|
for (i = 0; i < no_modif; i++) {
|
|
if (list_array[i].param_offset >= cmd_array[cmd].no_cmd_params)
|
|
return -EINVAL;
|
|
spi_cmd_buffer[3 + list_array[i].param_offset] =
|
|
list_array[i].new_param_val;
|
|
}
|
|
|
|
ret = st95hf_spi_send(&st95context->spicontext,
|
|
spi_cmd_buffer,
|
|
cmd_array[cmd].cmd_len,
|
|
cmd_array[cmd].req);
|
|
if (ret) {
|
|
dev_err(dev, "st95hf_spi_send failed with error %d\n", ret);
|
|
return ret;
|
|
}
|
|
|
|
if (cmd_array[cmd].req == SYNC && recv_res) {
|
|
unsigned char st95hf_response_arr[2];
|
|
|
|
ret = st95hf_spi_recv_response(&st95context->spicontext,
|
|
st95hf_response_arr);
|
|
if (ret < 0) {
|
|
dev_err(dev, "spi error from st95hf_spi_recv_response(), err = 0x%x\n",
|
|
ret);
|
|
return ret;
|
|
}
|
|
|
|
if (st95hf_response_arr[0]) {
|
|
dev_err(dev, "st95hf error from st95hf_spi_recv_response(), err = 0x%x\n",
|
|
st95hf_response_arr[0]);
|
|
return -EIO;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int st95hf_echo_command(struct st95hf_context *st95context)
|
|
{
|
|
int result = 0;
|
|
unsigned char echo_response;
|
|
|
|
result = st95hf_send_recv_cmd(st95context, CMD_ECHO, 0, NULL, false);
|
|
if (result)
|
|
return result;
|
|
|
|
/* If control reached here, response can be taken */
|
|
result = st95hf_spi_recv_echo_res(&st95context->spicontext,
|
|
&echo_response);
|
|
if (result) {
|
|
dev_err(&st95context->spicontext.spidev->dev,
|
|
"err: echo response receive error = 0x%x\n", result);
|
|
return result;
|
|
}
|
|
|
|
if (echo_response == ECHORESPONSE)
|
|
return 0;
|
|
|
|
dev_err(&st95context->spicontext.spidev->dev, "err: echo res is 0x%x\n",
|
|
echo_response);
|
|
|
|
return -EIO;
|
|
}
|
|
|
|
static int secondary_configuration_type4a(struct st95hf_context *stcontext)
|
|
{
|
|
int result = 0;
|
|
struct device *dev = &stcontext->nfcdev->dev;
|
|
|
|
/* 14443A config setting after select protocol */
|
|
result = st95hf_send_recv_cmd(stcontext,
|
|
CMD_ISO14443A_CONFIG,
|
|
0,
|
|
NULL,
|
|
true);
|
|
if (result) {
|
|
dev_err(dev, "type a config cmd, err = 0x%x\n", result);
|
|
return result;
|
|
}
|
|
|
|
/* 14443A demo gain setting */
|
|
result = st95hf_send_recv_cmd(stcontext,
|
|
CMD_ISO14443A_DEMOGAIN,
|
|
0,
|
|
NULL,
|
|
true);
|
|
if (result)
|
|
dev_err(dev, "type a demogain cmd, err = 0x%x\n", result);
|
|
|
|
return result;
|
|
}
|
|
|
|
static int secondary_configuration_type4b(struct st95hf_context *stcontext)
|
|
{
|
|
int result = 0;
|
|
struct device *dev = &stcontext->nfcdev->dev;
|
|
|
|
result = st95hf_send_recv_cmd(stcontext,
|
|
CMD_ISO14443B_DEMOGAIN,
|
|
0,
|
|
NULL,
|
|
true);
|
|
if (result)
|
|
dev_err(dev, "type b demogain cmd, err = 0x%x\n", result);
|
|
|
|
return result;
|
|
}
|
|
|
|
static int st95hf_select_protocol(struct st95hf_context *stcontext, int type)
|
|
{
|
|
int result = 0;
|
|
struct device *dev;
|
|
|
|
dev = &stcontext->nfcdev->dev;
|
|
|
|
switch (type) {
|
|
case NFC_DIGITAL_RF_TECH_106A:
|
|
stcontext->current_rf_tech = NFC_DIGITAL_RF_TECH_106A;
|
|
result = st95hf_send_recv_cmd(stcontext,
|
|
CMD_ISO14443A_PROTOCOL_SELECT,
|
|
0,
|
|
NULL,
|
|
true);
|
|
if (result) {
|
|
dev_err(dev, "protocol sel, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
|
|
/* secondary config. for 14443Type 4A after protocol select */
|
|
result = secondary_configuration_type4a(stcontext);
|
|
if (result) {
|
|
dev_err(dev, "type a secondary config, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
break;
|
|
case NFC_DIGITAL_RF_TECH_106B:
|
|
stcontext->current_rf_tech = NFC_DIGITAL_RF_TECH_106B;
|
|
result = st95hf_send_recv_cmd(stcontext,
|
|
CMD_ISO14443B_PROTOCOL_SELECT,
|
|
0,
|
|
NULL,
|
|
true);
|
|
if (result) {
|
|
dev_err(dev, "protocol sel send, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* delay of 5-6 ms is required after select protocol
|
|
* command in case of ISO14443 Type B
|
|
*/
|
|
usleep_range(50000, 60000);
|
|
|
|
/* secondary config. for 14443Type 4B after protocol select */
|
|
result = secondary_configuration_type4b(stcontext);
|
|
if (result) {
|
|
dev_err(dev, "type b secondary config, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
break;
|
|
case NFC_DIGITAL_RF_TECH_ISO15693:
|
|
stcontext->current_rf_tech = NFC_DIGITAL_RF_TECH_ISO15693;
|
|
result = st95hf_send_recv_cmd(stcontext,
|
|
CMD_ISO15693_PROTOCOL_SELECT,
|
|
0,
|
|
NULL,
|
|
true);
|
|
if (result) {
|
|
dev_err(dev, "protocol sel send, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void st95hf_send_st95enable_negativepulse(struct st95hf_context *st95con)
|
|
{
|
|
/* First make irq_in pin high */
|
|
gpio_set_value(st95con->enable_gpio, HIGH);
|
|
|
|
/* wait for 1 milisecond */
|
|
usleep_range(1000, 2000);
|
|
|
|
/* Make irq_in pin low */
|
|
gpio_set_value(st95con->enable_gpio, LOW);
|
|
|
|
/* wait for minimum interrupt pulse to make st95 active */
|
|
usleep_range(1000, 2000);
|
|
|
|
/* At end make it high */
|
|
gpio_set_value(st95con->enable_gpio, HIGH);
|
|
}
|
|
|
|
/*
|
|
* Send a reset sequence over SPI bus (Reset command + wait 3ms +
|
|
* negative pulse on st95hf enable gpio
|
|
*/
|
|
static int st95hf_send_spi_reset_sequence(struct st95hf_context *st95context)
|
|
{
|
|
int result = 0;
|
|
unsigned char reset_cmd = ST95HF_COMMAND_RESET;
|
|
|
|
result = st95hf_spi_send(&st95context->spicontext,
|
|
&reset_cmd,
|
|
ST95HF_RESET_CMD_LEN,
|
|
ASYNC);
|
|
if (result) {
|
|
dev_err(&st95context->spicontext.spidev->dev,
|
|
"spi reset sequence cmd error = %d", result);
|
|
return result;
|
|
}
|
|
|
|
/* wait for 3 milisecond to complete the controller reset process */
|
|
usleep_range(3000, 4000);
|
|
|
|
/* send negative pulse to make st95hf active */
|
|
st95hf_send_st95enable_negativepulse(st95context);
|
|
|
|
/* wait for 10 milisecond : HFO setup time */
|
|
usleep_range(10000, 20000);
|
|
|
|
return result;
|
|
}
|
|
|
|
static int st95hf_por_sequence(struct st95hf_context *st95context)
|
|
{
|
|
int nth_attempt = 1;
|
|
int result;
|
|
|
|
st95hf_send_st95enable_negativepulse(st95context);
|
|
|
|
usleep_range(5000, 6000);
|
|
do {
|
|
/* send an ECHO command and checks ST95HF response */
|
|
result = st95hf_echo_command(st95context);
|
|
|
|
dev_dbg(&st95context->spicontext.spidev->dev,
|
|
"response from echo function = 0x%x, attempt = %d\n",
|
|
result, nth_attempt);
|
|
|
|
if (!result)
|
|
return 0;
|
|
|
|
/* send an pulse on IRQ in case of the chip is on sleep state */
|
|
if (nth_attempt == 2)
|
|
st95hf_send_st95enable_negativepulse(st95context);
|
|
else
|
|
st95hf_send_spi_reset_sequence(st95context);
|
|
|
|
/* delay of 50 milisecond */
|
|
usleep_range(50000, 51000);
|
|
} while (nth_attempt++ < 3);
|
|
|
|
return -ETIMEDOUT;
|
|
}
|
|
|
|
static int iso14443_config_fdt(struct st95hf_context *st95context, int wtxm)
|
|
{
|
|
int result = 0;
|
|
struct device *dev = &st95context->spicontext.spidev->dev;
|
|
struct nfc_digital_dev *nfcddev = st95context->ddev;
|
|
unsigned char pp_typeb;
|
|
struct param_list new_params[2];
|
|
|
|
pp_typeb = cmd_array[CMD_ISO14443B_PROTOCOL_SELECT].cmd_params[2];
|
|
|
|
if (nfcddev->curr_protocol == NFC_PROTO_ISO14443 &&
|
|
st95context->fwi < 4)
|
|
st95context->fwi = 4;
|
|
|
|
new_params[0].param_offset = 2;
|
|
if (nfcddev->curr_protocol == NFC_PROTO_ISO14443)
|
|
new_params[0].new_param_val = st95context->fwi;
|
|
else if (nfcddev->curr_protocol == NFC_PROTO_ISO14443_B)
|
|
new_params[0].new_param_val = pp_typeb;
|
|
|
|
new_params[1].param_offset = 3;
|
|
new_params[1].new_param_val = wtxm;
|
|
|
|
switch (nfcddev->curr_protocol) {
|
|
case NFC_PROTO_ISO14443:
|
|
result = st95hf_send_recv_cmd(st95context,
|
|
CMD_ISO14443A_PROTOCOL_SELECT,
|
|
2,
|
|
new_params,
|
|
true);
|
|
if (result) {
|
|
dev_err(dev, "WTX type a sel proto, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
|
|
/* secondary config. for 14443Type 4A after protocol select */
|
|
result = secondary_configuration_type4a(st95context);
|
|
if (result) {
|
|
dev_err(dev, "WTX type a second. config, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
break;
|
|
case NFC_PROTO_ISO14443_B:
|
|
result = st95hf_send_recv_cmd(st95context,
|
|
CMD_ISO14443B_PROTOCOL_SELECT,
|
|
2,
|
|
new_params,
|
|
true);
|
|
if (result) {
|
|
dev_err(dev, "WTX type b sel proto, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
|
|
/* secondary config. for 14443Type 4B after protocol select */
|
|
result = secondary_configuration_type4b(st95context);
|
|
if (result) {
|
|
dev_err(dev, "WTX type b second. config, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int st95hf_handle_wtx(struct st95hf_context *stcontext,
|
|
bool new_wtx,
|
|
int wtx_val)
|
|
{
|
|
int result = 0;
|
|
unsigned char val_mm = 0;
|
|
struct param_list new_params[1];
|
|
struct nfc_digital_dev *nfcddev = stcontext->ddev;
|
|
struct device *dev = &stcontext->nfcdev->dev;
|
|
|
|
if (new_wtx) {
|
|
result = iso14443_config_fdt(stcontext, wtx_val & 0x3f);
|
|
if (result) {
|
|
dev_err(dev, "Config. setting error on WTX req, err = 0x%x\n",
|
|
result);
|
|
return result;
|
|
}
|
|
|
|
/* Send response of wtx with ASYNC as no response expected */
|
|
new_params[0].param_offset = 1;
|
|
new_params[0].new_param_val = wtx_val;
|
|
|
|
result = st95hf_send_recv_cmd(stcontext,
|
|
CMD_WTX_RESPONSE,
|
|
1,
|
|
new_params,
|
|
false);
|
|
if (result)
|
|
dev_err(dev, "WTX response send, err = 0x%x\n", result);
|
|
return result;
|
|
}
|
|
|
|
/* if no new wtx, cofigure with default values */
|
|
if (nfcddev->curr_protocol == NFC_PROTO_ISO14443)
|
|
val_mm = cmd_array[CMD_ISO14443A_PROTOCOL_SELECT].cmd_params[3];
|
|
else if (nfcddev->curr_protocol == NFC_PROTO_ISO14443_B)
|
|
val_mm = cmd_array[CMD_ISO14443B_PROTOCOL_SELECT].cmd_params[3];
|
|
|
|
result = iso14443_config_fdt(stcontext, val_mm);
|
|
if (result)
|
|
dev_err(dev, "Default config. setting error after WTX processing, err = 0x%x\n",
|
|
result);
|
|
|
|
return result;
|
|
}
|
|
|
|
static int st95hf_error_handling(struct st95hf_context *stcontext,
|
|
struct sk_buff *skb_resp,
|
|
int res_len)
|
|
{
|
|
int result = 0;
|
|
unsigned char error_byte;
|
|
struct device *dev = &stcontext->nfcdev->dev;
|
|
|
|
/* First check ST95HF specific error */
|
|
if (skb_resp->data[0] & ST95HF_ERR_MASK) {
|
|
if (skb_resp->data[0] == ST95HF_TIMEOUT_ERROR)
|
|
result = -ETIMEDOUT;
|
|
else
|
|
result = -EIO;
|
|
return result;
|
|
}
|
|
|
|
/* Check for CRC err only if CRC is present in the tag response */
|
|
switch (stcontext->current_rf_tech) {
|
|
case NFC_DIGITAL_RF_TECH_106A:
|
|
if (stcontext->sendrcv_trflag == TRFLAG_NFCA_STD_FRAME_CRC) {
|
|
error_byte = skb_resp->data[res_len - 3];
|
|
if (error_byte & ST95HF_NFCA_CRC_ERR_MASK) {
|
|
/* CRC error occurred */
|
|
dev_err(dev, "CRC error, byte received = 0x%x\n",
|
|
error_byte);
|
|
result = -EIO;
|
|
}
|
|
}
|
|
break;
|
|
case NFC_DIGITAL_RF_TECH_106B:
|
|
case NFC_DIGITAL_RF_TECH_ISO15693:
|
|
error_byte = skb_resp->data[res_len - 1];
|
|
if (error_byte & ST95HF_NFCB_CRC_ERR_MASK) {
|
|
/* CRC error occurred */
|
|
dev_err(dev, "CRC error, byte received = 0x%x\n",
|
|
error_byte);
|
|
result = -EIO;
|
|
}
|
|
break;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
static int st95hf_response_handler(struct st95hf_context *stcontext,
|
|
struct sk_buff *skb_resp,
|
|
int res_len)
|
|
{
|
|
int result = 0;
|
|
int skb_len;
|
|
unsigned char val_mm;
|
|
struct nfc_digital_dev *nfcddev = stcontext->ddev;
|
|
struct device *dev = &stcontext->nfcdev->dev;
|
|
struct st95_digital_cmd_complete_arg *cb_arg;
|
|
|
|
cb_arg = &stcontext->complete_cb_arg;
|
|
|
|
/* Process the response */
|
|
skb_put(skb_resp, res_len);
|
|
|
|
/* Remove st95 header */
|
|
skb_pull(skb_resp, 2);
|
|
|
|
skb_len = skb_resp->len;
|
|
|
|
/* check if it is case of RATS request reply & FWI is present */
|
|
if (nfcddev->curr_protocol == NFC_PROTO_ISO14443 && cb_arg->rats &&
|
|
(skb_resp->data[1] & RATS_TB1_PRESENT_MASK)) {
|
|
if (skb_resp->data[1] & RATS_TA1_PRESENT_MASK)
|
|
stcontext->fwi =
|
|
(skb_resp->data[3] & TB1_FWI_MASK) >> 4;
|
|
else
|
|
stcontext->fwi =
|
|
(skb_resp->data[2] & TB1_FWI_MASK) >> 4;
|
|
|
|
val_mm = cmd_array[CMD_ISO14443A_PROTOCOL_SELECT].cmd_params[3];
|
|
|
|
result = iso14443_config_fdt(stcontext, val_mm);
|
|
if (result) {
|
|
dev_err(dev, "error in config_fdt to handle fwi of ATS, error=%d\n",
|
|
result);
|
|
return result;
|
|
}
|
|
}
|
|
cb_arg->rats = false;
|
|
|
|
/* Remove CRC bytes only if received frames data has an eod (CRC) */
|
|
switch (stcontext->current_rf_tech) {
|
|
case NFC_DIGITAL_RF_TECH_106A:
|
|
if (stcontext->sendrcv_trflag == TRFLAG_NFCA_STD_FRAME_CRC)
|
|
skb_trim(skb_resp, (skb_len - 5));
|
|
else
|
|
skb_trim(skb_resp, (skb_len - 3));
|
|
break;
|
|
case NFC_DIGITAL_RF_TECH_106B:
|
|
case NFC_DIGITAL_RF_TECH_ISO15693:
|
|
skb_trim(skb_resp, (skb_len - 3));
|
|
break;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
static irqreturn_t st95hf_irq_handler(int irq, void *st95hfcontext)
|
|
{
|
|
struct st95hf_context *stcontext =
|
|
(struct st95hf_context *)st95hfcontext;
|
|
|
|
if (stcontext->spicontext.req_issync) {
|
|
complete(&stcontext->spicontext.done);
|
|
stcontext->spicontext.req_issync = false;
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
return IRQ_WAKE_THREAD;
|
|
}
|
|
|
|
static irqreturn_t st95hf_irq_thread_handler(int irq, void *st95hfcontext)
|
|
{
|
|
int result = 0;
|
|
int res_len;
|
|
static bool wtx;
|
|
struct device *spidevice;
|
|
struct sk_buff *skb_resp;
|
|
struct st95hf_context *stcontext =
|
|
(struct st95hf_context *)st95hfcontext;
|
|
struct st95_digital_cmd_complete_arg *cb_arg;
|
|
|
|
spidevice = &stcontext->spicontext.spidev->dev;
|
|
|
|
/*
|
|
* check semaphore, if not down() already, then we don't
|
|
* know in which context the ISR is called and surely it
|
|
* will be a bug. Note that down() of the semaphore is done
|
|
* in the corresponding st95hf_in_send_cmd() and then
|
|
* only this ISR should be called. ISR will up() the
|
|
* semaphore before leaving. Hence when the ISR is called
|
|
* the correct behaviour is down_trylock() should always
|
|
* return 1 (indicating semaphore cant be taken and hence no
|
|
* change in semaphore count).
|
|
* If not, then we up() the semaphore and crash on
|
|
* a BUG() !
|
|
*/
|
|
if (!down_trylock(&stcontext->exchange_lock)) {
|
|
up(&stcontext->exchange_lock);
|
|
WARN(1, "unknown context in ST95HF ISR");
|
|
return IRQ_NONE;
|
|
}
|
|
|
|
cb_arg = &stcontext->complete_cb_arg;
|
|
skb_resp = cb_arg->skb_resp;
|
|
|
|
mutex_lock(&stcontext->rm_lock);
|
|
res_len = st95hf_spi_recv_response(&stcontext->spicontext,
|
|
skb_resp->data);
|
|
if (res_len < 0) {
|
|
dev_err(spidevice, "TISR spi response err = 0x%x\n", res_len);
|
|
result = res_len;
|
|
goto end;
|
|
}
|
|
|
|
/* if stcontext->nfcdev_free is true, it means remove already ran */
|
|
if (stcontext->nfcdev_free) {
|
|
result = -ENODEV;
|
|
goto end;
|
|
}
|
|
|
|
if (skb_resp->data[2] == WTX_REQ_FROM_TAG) {
|
|
/* Request for new FWT from tag */
|
|
result = st95hf_handle_wtx(stcontext, true, skb_resp->data[3]);
|
|
if (result)
|
|
goto end;
|
|
|
|
wtx = true;
|
|
mutex_unlock(&stcontext->rm_lock);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
result = st95hf_error_handling(stcontext, skb_resp, res_len);
|
|
if (result)
|
|
goto end;
|
|
|
|
result = st95hf_response_handler(stcontext, skb_resp, res_len);
|
|
if (result)
|
|
goto end;
|
|
|
|
/*
|
|
* If select protocol is done on wtx req. do select protocol
|
|
* again with default values
|
|
*/
|
|
if (wtx) {
|
|
wtx = false;
|
|
result = st95hf_handle_wtx(stcontext, false, 0);
|
|
if (result)
|
|
goto end;
|
|
}
|
|
|
|
/* call digital layer callback */
|
|
cb_arg->complete_cb(stcontext->ddev, cb_arg->cb_usrarg, skb_resp);
|
|
|
|
/* up the semaphore before returning */
|
|
up(&stcontext->exchange_lock);
|
|
mutex_unlock(&stcontext->rm_lock);
|
|
|
|
return IRQ_HANDLED;
|
|
|
|
end:
|
|
kfree_skb(skb_resp);
|
|
wtx = false;
|
|
cb_arg->rats = false;
|
|
skb_resp = ERR_PTR(result);
|
|
/* call of callback with error */
|
|
cb_arg->complete_cb(stcontext->ddev, cb_arg->cb_usrarg, skb_resp);
|
|
/* up the semaphore before returning */
|
|
up(&stcontext->exchange_lock);
|
|
mutex_unlock(&stcontext->rm_lock);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/* NFC ops functions definition */
|
|
static int st95hf_in_configure_hw(struct nfc_digital_dev *ddev,
|
|
int type,
|
|
int param)
|
|
{
|
|
struct st95hf_context *stcontext = nfc_digital_get_drvdata(ddev);
|
|
|
|
if (type == NFC_DIGITAL_CONFIG_RF_TECH)
|
|
return st95hf_select_protocol(stcontext, param);
|
|
|
|
if (type == NFC_DIGITAL_CONFIG_FRAMING) {
|
|
switch (param) {
|
|
case NFC_DIGITAL_FRAMING_NFCA_SHORT:
|
|
stcontext->sendrcv_trflag = TRFLAG_NFCA_SHORT_FRAME;
|
|
break;
|
|
case NFC_DIGITAL_FRAMING_NFCA_STANDARD:
|
|
stcontext->sendrcv_trflag = TRFLAG_NFCA_STD_FRAME;
|
|
break;
|
|
case NFC_DIGITAL_FRAMING_NFCA_T4T:
|
|
case NFC_DIGITAL_FRAMING_NFCA_NFC_DEP:
|
|
case NFC_DIGITAL_FRAMING_NFCA_STANDARD_WITH_CRC_A:
|
|
stcontext->sendrcv_trflag = TRFLAG_NFCA_STD_FRAME_CRC;
|
|
break;
|
|
case NFC_DIGITAL_FRAMING_NFCB:
|
|
case NFC_DIGITAL_FRAMING_ISO15693_INVENTORY:
|
|
case NFC_DIGITAL_FRAMING_ISO15693_T5T:
|
|
break;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int rf_off(struct st95hf_context *stcontext)
|
|
{
|
|
int rc;
|
|
struct device *dev;
|
|
|
|
dev = &stcontext->nfcdev->dev;
|
|
|
|
rc = st95hf_send_recv_cmd(stcontext, CMD_FIELD_OFF, 0, NULL, true);
|
|
if (rc)
|
|
dev_err(dev, "protocol sel send field off, err = 0x%x\n", rc);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int st95hf_in_send_cmd(struct nfc_digital_dev *ddev,
|
|
struct sk_buff *skb,
|
|
u16 timeout,
|
|
nfc_digital_cmd_complete_t cb,
|
|
void *arg)
|
|
{
|
|
struct st95hf_context *stcontext = nfc_digital_get_drvdata(ddev);
|
|
int rc;
|
|
struct sk_buff *skb_resp;
|
|
int len_data_to_tag = 0;
|
|
|
|
skb_resp = nfc_alloc_recv_skb(MAX_RESPONSE_BUFFER_SIZE, GFP_KERNEL);
|
|
if (!skb_resp) {
|
|
rc = -ENOMEM;
|
|
goto error;
|
|
}
|
|
|
|
switch (stcontext->current_rf_tech) {
|
|
case NFC_DIGITAL_RF_TECH_106A:
|
|
len_data_to_tag = skb->len + 1;
|
|
skb_put_u8(skb, stcontext->sendrcv_trflag);
|
|
break;
|
|
case NFC_DIGITAL_RF_TECH_106B:
|
|
case NFC_DIGITAL_RF_TECH_ISO15693:
|
|
len_data_to_tag = skb->len;
|
|
break;
|
|
default:
|
|
rc = -EINVAL;
|
|
goto free_skb_resp;
|
|
}
|
|
|
|
skb_push(skb, 3);
|
|
skb->data[0] = ST95HF_COMMAND_SEND;
|
|
skb->data[1] = SEND_RECEIVE_CMD;
|
|
skb->data[2] = len_data_to_tag;
|
|
|
|
stcontext->complete_cb_arg.skb_resp = skb_resp;
|
|
stcontext->complete_cb_arg.cb_usrarg = arg;
|
|
stcontext->complete_cb_arg.complete_cb = cb;
|
|
|
|
if ((skb->data[3] == ISO14443A_RATS_REQ) &&
|
|
ddev->curr_protocol == NFC_PROTO_ISO14443)
|
|
stcontext->complete_cb_arg.rats = true;
|
|
|
|
/*
|
|
* down the semaphore to indicate to remove func that an
|
|
* ISR is pending, note that it will not block here in any case.
|
|
* If found blocked, it is a BUG!
|
|
*/
|
|
rc = down_killable(&stcontext->exchange_lock);
|
|
if (rc) {
|
|
WARN(1, "Semaphore is not found up in st95hf_in_send_cmd\n");
|
|
return rc;
|
|
}
|
|
|
|
rc = st95hf_spi_send(&stcontext->spicontext, skb->data,
|
|
skb->len,
|
|
ASYNC);
|
|
if (rc) {
|
|
dev_err(&stcontext->nfcdev->dev,
|
|
"Error %d trying to perform data_exchange", rc);
|
|
/* up the semaphore since ISR will never come in this case */
|
|
up(&stcontext->exchange_lock);
|
|
goto free_skb_resp;
|
|
}
|
|
|
|
kfree_skb(skb);
|
|
|
|
return rc;
|
|
|
|
free_skb_resp:
|
|
kfree_skb(skb_resp);
|
|
error:
|
|
return rc;
|
|
}
|
|
|
|
/* p2p will be supported in a later release ! */
|
|
static int st95hf_tg_configure_hw(struct nfc_digital_dev *ddev,
|
|
int type,
|
|
int param)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int st95hf_tg_send_cmd(struct nfc_digital_dev *ddev,
|
|
struct sk_buff *skb,
|
|
u16 timeout,
|
|
nfc_digital_cmd_complete_t cb,
|
|
void *arg)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int st95hf_tg_listen(struct nfc_digital_dev *ddev,
|
|
u16 timeout,
|
|
nfc_digital_cmd_complete_t cb,
|
|
void *arg)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int st95hf_tg_get_rf_tech(struct nfc_digital_dev *ddev, u8 *rf_tech)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static int st95hf_switch_rf(struct nfc_digital_dev *ddev, bool on)
|
|
{
|
|
u8 rf_tech;
|
|
struct st95hf_context *stcontext = nfc_digital_get_drvdata(ddev);
|
|
|
|
rf_tech = ddev->curr_rf_tech;
|
|
|
|
if (on)
|
|
/* switch on RF field */
|
|
return st95hf_select_protocol(stcontext, rf_tech);
|
|
|
|
/* switch OFF RF field */
|
|
return rf_off(stcontext);
|
|
}
|
|
|
|
/* TODO st95hf_abort_cmd */
|
|
static void st95hf_abort_cmd(struct nfc_digital_dev *ddev)
|
|
{
|
|
}
|
|
|
|
static struct nfc_digital_ops st95hf_nfc_digital_ops = {
|
|
.in_configure_hw = st95hf_in_configure_hw,
|
|
.in_send_cmd = st95hf_in_send_cmd,
|
|
|
|
.tg_listen = st95hf_tg_listen,
|
|
.tg_configure_hw = st95hf_tg_configure_hw,
|
|
.tg_send_cmd = st95hf_tg_send_cmd,
|
|
.tg_get_rf_tech = st95hf_tg_get_rf_tech,
|
|
|
|
.switch_rf = st95hf_switch_rf,
|
|
.abort_cmd = st95hf_abort_cmd,
|
|
};
|
|
|
|
static const struct spi_device_id st95hf_id[] = {
|
|
{ "st95hf", 0 },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(spi, st95hf_id);
|
|
|
|
static const struct of_device_id st95hf_spi_of_match[] = {
|
|
{ .compatible = "st,st95hf" },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(of, st95hf_spi_of_match);
|
|
|
|
static int st95hf_probe(struct spi_device *nfc_spi_dev)
|
|
{
|
|
int ret;
|
|
|
|
struct st95hf_context *st95context;
|
|
struct st95hf_spi_context *spicontext;
|
|
|
|
nfc_info(&nfc_spi_dev->dev, "ST95HF driver probe called.\n");
|
|
|
|
st95context = devm_kzalloc(&nfc_spi_dev->dev,
|
|
sizeof(struct st95hf_context),
|
|
GFP_KERNEL);
|
|
if (!st95context)
|
|
return -ENOMEM;
|
|
|
|
spicontext = &st95context->spicontext;
|
|
|
|
spicontext->spidev = nfc_spi_dev;
|
|
|
|
st95context->fwi =
|
|
cmd_array[CMD_ISO14443A_PROTOCOL_SELECT].cmd_params[2];
|
|
|
|
if (device_property_present(&nfc_spi_dev->dev, "st95hfvin")) {
|
|
st95context->st95hf_supply =
|
|
devm_regulator_get(&nfc_spi_dev->dev,
|
|
"st95hfvin");
|
|
if (IS_ERR(st95context->st95hf_supply)) {
|
|
dev_err(&nfc_spi_dev->dev, "failed to acquire regulator\n");
|
|
return PTR_ERR(st95context->st95hf_supply);
|
|
}
|
|
|
|
ret = regulator_enable(st95context->st95hf_supply);
|
|
if (ret) {
|
|
dev_err(&nfc_spi_dev->dev, "failed to enable regulator\n");
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
init_completion(&spicontext->done);
|
|
mutex_init(&spicontext->spi_lock);
|
|
|
|
/*
|
|
* Store spicontext in spi device object for using it in
|
|
* remove function
|
|
*/
|
|
dev_set_drvdata(&nfc_spi_dev->dev, spicontext);
|
|
|
|
st95context->enable_gpio =
|
|
of_get_named_gpio(nfc_spi_dev->dev.of_node,
|
|
"enable-gpio",
|
|
0);
|
|
if (!gpio_is_valid(st95context->enable_gpio)) {
|
|
dev_err(&nfc_spi_dev->dev, "No valid enable gpio\n");
|
|
ret = st95context->enable_gpio;
|
|
goto err_disable_regulator;
|
|
}
|
|
|
|
ret = devm_gpio_request_one(&nfc_spi_dev->dev, st95context->enable_gpio,
|
|
GPIOF_DIR_OUT | GPIOF_INIT_HIGH,
|
|
"enable_gpio");
|
|
if (ret)
|
|
goto err_disable_regulator;
|
|
|
|
if (nfc_spi_dev->irq > 0) {
|
|
if (devm_request_threaded_irq(&nfc_spi_dev->dev,
|
|
nfc_spi_dev->irq,
|
|
st95hf_irq_handler,
|
|
st95hf_irq_thread_handler,
|
|
IRQF_TRIGGER_FALLING,
|
|
"st95hf",
|
|
(void *)st95context) < 0) {
|
|
dev_err(&nfc_spi_dev->dev, "err: irq request for st95hf is failed\n");
|
|
ret = -EINVAL;
|
|
goto err_disable_regulator;
|
|
}
|
|
} else {
|
|
dev_err(&nfc_spi_dev->dev, "not a valid IRQ associated with ST95HF\n");
|
|
ret = -EINVAL;
|
|
goto err_disable_regulator;
|
|
}
|
|
|
|
/*
|
|
* First reset SPI to handle warm reset of the system.
|
|
* It will put the ST95HF device in Power ON state
|
|
* which make the state of device identical to state
|
|
* at the time of cold reset of the system.
|
|
*/
|
|
ret = st95hf_send_spi_reset_sequence(st95context);
|
|
if (ret) {
|
|
dev_err(&nfc_spi_dev->dev, "err: spi_reset_sequence failed\n");
|
|
goto err_disable_regulator;
|
|
}
|
|
|
|
/* call PowerOnReset sequence of ST95hf to activate it */
|
|
ret = st95hf_por_sequence(st95context);
|
|
if (ret) {
|
|
dev_err(&nfc_spi_dev->dev, "err: por seq failed for st95hf\n");
|
|
goto err_disable_regulator;
|
|
}
|
|
|
|
/* create NFC dev object and register with NFC Subsystem */
|
|
st95context->ddev = nfc_digital_allocate_device(&st95hf_nfc_digital_ops,
|
|
ST95HF_SUPPORTED_PROT,
|
|
ST95HF_CAPABILITIES,
|
|
ST95HF_HEADROOM_LEN,
|
|
ST95HF_TAILROOM_LEN);
|
|
if (!st95context->ddev) {
|
|
ret = -ENOMEM;
|
|
goto err_disable_regulator;
|
|
}
|
|
|
|
st95context->nfcdev = st95context->ddev->nfc_dev;
|
|
nfc_digital_set_parent_dev(st95context->ddev, &nfc_spi_dev->dev);
|
|
|
|
ret = nfc_digital_register_device(st95context->ddev);
|
|
if (ret) {
|
|
dev_err(&st95context->nfcdev->dev, "st95hf registration failed\n");
|
|
goto err_free_digital_device;
|
|
}
|
|
|
|
/* store st95context in nfc device object */
|
|
nfc_digital_set_drvdata(st95context->ddev, st95context);
|
|
|
|
sema_init(&st95context->exchange_lock, 1);
|
|
mutex_init(&st95context->rm_lock);
|
|
|
|
return ret;
|
|
|
|
err_free_digital_device:
|
|
nfc_digital_free_device(st95context->ddev);
|
|
err_disable_regulator:
|
|
if (st95context->st95hf_supply)
|
|
regulator_disable(st95context->st95hf_supply);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int st95hf_remove(struct spi_device *nfc_spi_dev)
|
|
{
|
|
int result = 0;
|
|
unsigned char reset_cmd = ST95HF_COMMAND_RESET;
|
|
struct st95hf_spi_context *spictx = dev_get_drvdata(&nfc_spi_dev->dev);
|
|
|
|
struct st95hf_context *stcontext = container_of(spictx,
|
|
struct st95hf_context,
|
|
spicontext);
|
|
|
|
mutex_lock(&stcontext->rm_lock);
|
|
|
|
nfc_digital_unregister_device(stcontext->ddev);
|
|
nfc_digital_free_device(stcontext->ddev);
|
|
stcontext->nfcdev_free = true;
|
|
|
|
mutex_unlock(&stcontext->rm_lock);
|
|
|
|
/* if last in_send_cmd's ISR is pending, wait for it to finish */
|
|
result = down_killable(&stcontext->exchange_lock);
|
|
if (result == -EINTR)
|
|
dev_err(&spictx->spidev->dev, "sleep for semaphore interrupted by signal\n");
|
|
|
|
/* next reset the ST95HF controller */
|
|
result = st95hf_spi_send(&stcontext->spicontext,
|
|
&reset_cmd,
|
|
ST95HF_RESET_CMD_LEN,
|
|
ASYNC);
|
|
if (result) {
|
|
dev_err(&spictx->spidev->dev,
|
|
"ST95HF reset failed in remove() err = %d\n", result);
|
|
return result;
|
|
}
|
|
|
|
/* wait for 3 ms to complete the controller reset process */
|
|
usleep_range(3000, 4000);
|
|
|
|
/* disable regulator */
|
|
if (stcontext->st95hf_supply)
|
|
regulator_disable(stcontext->st95hf_supply);
|
|
|
|
return result;
|
|
}
|
|
|
|
/* Register as SPI protocol driver */
|
|
static struct spi_driver st95hf_driver = {
|
|
.driver = {
|
|
.name = "st95hf",
|
|
.owner = THIS_MODULE,
|
|
.of_match_table = of_match_ptr(st95hf_spi_of_match),
|
|
},
|
|
.id_table = st95hf_id,
|
|
.probe = st95hf_probe,
|
|
.remove = st95hf_remove,
|
|
};
|
|
|
|
module_spi_driver(st95hf_driver);
|
|
|
|
MODULE_AUTHOR("Shikha Singh <shikha.singh@st.com>");
|
|
MODULE_DESCRIPTION("ST NFC Transceiver ST95HF driver");
|
|
MODULE_LICENSE("GPL v2");
|