forked from Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
315 lines
7.0 KiB
315 lines
7.0 KiB
// SPDX-License-Identifier: GPL-2.0-only |
|
/* |
|
* SPI Link Layer for ST NCI based Driver |
|
* Copyright (C) 2014-2015 STMicroelectronics SAS. All rights reserved. |
|
*/ |
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
|
|
|
#include <linux/module.h> |
|
#include <linux/spi/spi.h> |
|
#include <linux/gpio/consumer.h> |
|
#include <linux/acpi.h> |
|
#include <linux/interrupt.h> |
|
#include <linux/delay.h> |
|
#include <linux/nfc.h> |
|
#include <linux/of.h> |
|
#include <net/nfc/nci.h> |
|
|
|
#include "st-nci.h" |
|
|
|
#define DRIVER_DESC "NCI NFC driver for ST_NCI" |
|
|
|
/* ndlc header */ |
|
#define ST_NCI_FRAME_HEADROOM 1 |
|
#define ST_NCI_FRAME_TAILROOM 0 |
|
|
|
#define ST_NCI_SPI_MIN_SIZE 4 /* PCB(1) + NCI Packet header(3) */ |
|
#define ST_NCI_SPI_MAX_SIZE 250 /* req 4.2.1 */ |
|
|
|
#define ST_NCI_DRIVER_NAME "st_nci" |
|
#define ST_NCI_SPI_DRIVER_NAME "st_nci_spi" |
|
|
|
struct st_nci_spi_phy { |
|
struct spi_device *spi_dev; |
|
struct llt_ndlc *ndlc; |
|
|
|
bool irq_active; |
|
|
|
struct gpio_desc *gpiod_reset; |
|
|
|
struct st_nci_se_status se_status; |
|
}; |
|
|
|
static int st_nci_spi_enable(void *phy_id) |
|
{ |
|
struct st_nci_spi_phy *phy = phy_id; |
|
|
|
gpiod_set_value(phy->gpiod_reset, 0); |
|
usleep_range(10000, 15000); |
|
gpiod_set_value(phy->gpiod_reset, 1); |
|
usleep_range(80000, 85000); |
|
|
|
if (phy->ndlc->powered == 0 && phy->irq_active == 0) { |
|
enable_irq(phy->spi_dev->irq); |
|
phy->irq_active = true; |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static void st_nci_spi_disable(void *phy_id) |
|
{ |
|
struct st_nci_spi_phy *phy = phy_id; |
|
|
|
disable_irq_nosync(phy->spi_dev->irq); |
|
phy->irq_active = false; |
|
} |
|
|
|
/* |
|
* Writing a frame must not return the number of written bytes. |
|
* It must return either zero for success, or <0 for error. |
|
* In addition, it must not alter the skb |
|
*/ |
|
static int st_nci_spi_write(void *phy_id, struct sk_buff *skb) |
|
{ |
|
int r; |
|
struct st_nci_spi_phy *phy = phy_id; |
|
struct spi_device *dev = phy->spi_dev; |
|
struct sk_buff *skb_rx; |
|
u8 buf[ST_NCI_SPI_MAX_SIZE + NCI_DATA_HDR_SIZE + |
|
ST_NCI_FRAME_HEADROOM + ST_NCI_FRAME_TAILROOM]; |
|
struct spi_transfer spi_xfer = { |
|
.tx_buf = skb->data, |
|
.rx_buf = buf, |
|
.len = skb->len, |
|
}; |
|
|
|
if (phy->ndlc->hard_fault != 0) |
|
return phy->ndlc->hard_fault; |
|
|
|
r = spi_sync_transfer(dev, &spi_xfer, 1); |
|
/* |
|
* We may have received some valuable data on miso line. |
|
* Send them back in the ndlc state machine. |
|
*/ |
|
if (!r) { |
|
skb_rx = alloc_skb(skb->len, GFP_KERNEL); |
|
if (!skb_rx) |
|
return -ENOMEM; |
|
|
|
skb_put(skb_rx, skb->len); |
|
memcpy(skb_rx->data, buf, skb->len); |
|
ndlc_recv(phy->ndlc, skb_rx); |
|
} |
|
|
|
return r; |
|
} |
|
|
|
/* |
|
* Reads an ndlc frame and returns it in a newly allocated sk_buff. |
|
* returns: |
|
* 0 : if received frame is complete |
|
* -EREMOTEIO : i2c read error (fatal) |
|
* -EBADMSG : frame was incorrect and discarded |
|
* -ENOMEM : cannot allocate skb, frame dropped |
|
*/ |
|
static int st_nci_spi_read(struct st_nci_spi_phy *phy, |
|
struct sk_buff **skb) |
|
{ |
|
int r; |
|
u8 len; |
|
u8 buf[ST_NCI_SPI_MAX_SIZE]; |
|
struct spi_device *dev = phy->spi_dev; |
|
struct spi_transfer spi_xfer = { |
|
.rx_buf = buf, |
|
.len = ST_NCI_SPI_MIN_SIZE, |
|
}; |
|
|
|
r = spi_sync_transfer(dev, &spi_xfer, 1); |
|
if (r < 0) |
|
return -EREMOTEIO; |
|
|
|
len = be16_to_cpu(*(__be16 *) (buf + 2)); |
|
if (len > ST_NCI_SPI_MAX_SIZE) { |
|
nfc_err(&dev->dev, "invalid frame len\n"); |
|
phy->ndlc->hard_fault = 1; |
|
return -EBADMSG; |
|
} |
|
|
|
*skb = alloc_skb(ST_NCI_SPI_MIN_SIZE + len, GFP_KERNEL); |
|
if (*skb == NULL) |
|
return -ENOMEM; |
|
|
|
skb_reserve(*skb, ST_NCI_SPI_MIN_SIZE); |
|
skb_put(*skb, ST_NCI_SPI_MIN_SIZE); |
|
memcpy((*skb)->data, buf, ST_NCI_SPI_MIN_SIZE); |
|
|
|
if (!len) |
|
return 0; |
|
|
|
spi_xfer.len = len; |
|
r = spi_sync_transfer(dev, &spi_xfer, 1); |
|
if (r < 0) { |
|
kfree_skb(*skb); |
|
return -EREMOTEIO; |
|
} |
|
|
|
skb_put(*skb, len); |
|
memcpy((*skb)->data + ST_NCI_SPI_MIN_SIZE, buf, len); |
|
|
|
return 0; |
|
} |
|
|
|
/* |
|
* Reads an ndlc frame from the chip. |
|
* |
|
* On ST21NFCB, IRQ goes in idle state when read starts. |
|
*/ |
|
static irqreturn_t st_nci_irq_thread_fn(int irq, void *phy_id) |
|
{ |
|
struct st_nci_spi_phy *phy = phy_id; |
|
struct spi_device *dev; |
|
struct sk_buff *skb = NULL; |
|
int r; |
|
|
|
if (!phy || !phy->ndlc || irq != phy->spi_dev->irq) { |
|
WARN_ON_ONCE(1); |
|
return IRQ_NONE; |
|
} |
|
|
|
dev = phy->spi_dev; |
|
dev_dbg(&dev->dev, "IRQ\n"); |
|
|
|
if (phy->ndlc->hard_fault) |
|
return IRQ_HANDLED; |
|
|
|
if (!phy->ndlc->powered) { |
|
st_nci_spi_disable(phy); |
|
return IRQ_HANDLED; |
|
} |
|
|
|
r = st_nci_spi_read(phy, &skb); |
|
if (r == -EREMOTEIO || r == -ENOMEM || r == -EBADMSG) |
|
return IRQ_HANDLED; |
|
|
|
ndlc_recv(phy->ndlc, skb); |
|
|
|
return IRQ_HANDLED; |
|
} |
|
|
|
static struct nfc_phy_ops spi_phy_ops = { |
|
.write = st_nci_spi_write, |
|
.enable = st_nci_spi_enable, |
|
.disable = st_nci_spi_disable, |
|
}; |
|
|
|
static const struct acpi_gpio_params reset_gpios = { 1, 0, false }; |
|
|
|
static const struct acpi_gpio_mapping acpi_st_nci_gpios[] = { |
|
{ "reset-gpios", &reset_gpios, 1 }, |
|
{}, |
|
}; |
|
|
|
static int st_nci_spi_probe(struct spi_device *dev) |
|
{ |
|
struct st_nci_spi_phy *phy; |
|
int r; |
|
|
|
dev_dbg(&dev->dev, "%s\n", __func__); |
|
dev_dbg(&dev->dev, "IRQ: %d\n", dev->irq); |
|
|
|
/* Check SPI platform functionnalities */ |
|
if (!dev) { |
|
pr_debug("%s: dev is NULL. Device is not accessible.\n", |
|
__func__); |
|
return -ENODEV; |
|
} |
|
|
|
phy = devm_kzalloc(&dev->dev, sizeof(struct st_nci_spi_phy), |
|
GFP_KERNEL); |
|
if (!phy) |
|
return -ENOMEM; |
|
|
|
phy->spi_dev = dev; |
|
|
|
spi_set_drvdata(dev, phy); |
|
|
|
r = devm_acpi_dev_add_driver_gpios(&dev->dev, acpi_st_nci_gpios); |
|
if (r) |
|
dev_dbg(&dev->dev, "Unable to add GPIO mapping table\n"); |
|
|
|
/* Get RESET GPIO */ |
|
phy->gpiod_reset = devm_gpiod_get(&dev->dev, "reset", GPIOD_OUT_HIGH); |
|
if (IS_ERR(phy->gpiod_reset)) { |
|
nfc_err(&dev->dev, "Unable to get RESET GPIO\n"); |
|
return PTR_ERR(phy->gpiod_reset); |
|
} |
|
|
|
phy->se_status.is_ese_present = |
|
device_property_read_bool(&dev->dev, "ese-present"); |
|
phy->se_status.is_uicc_present = |
|
device_property_read_bool(&dev->dev, "uicc-present"); |
|
|
|
r = ndlc_probe(phy, &spi_phy_ops, &dev->dev, |
|
ST_NCI_FRAME_HEADROOM, ST_NCI_FRAME_TAILROOM, |
|
&phy->ndlc, &phy->se_status); |
|
if (r < 0) { |
|
nfc_err(&dev->dev, "Unable to register ndlc layer\n"); |
|
return r; |
|
} |
|
|
|
phy->irq_active = true; |
|
r = devm_request_threaded_irq(&dev->dev, dev->irq, NULL, |
|
st_nci_irq_thread_fn, |
|
IRQF_ONESHOT, |
|
ST_NCI_SPI_DRIVER_NAME, phy); |
|
if (r < 0) |
|
nfc_err(&dev->dev, "Unable to register IRQ handler\n"); |
|
|
|
return r; |
|
} |
|
|
|
static int st_nci_spi_remove(struct spi_device *dev) |
|
{ |
|
struct st_nci_spi_phy *phy = spi_get_drvdata(dev); |
|
|
|
dev_dbg(&dev->dev, "%s\n", __func__); |
|
|
|
ndlc_remove(phy->ndlc); |
|
|
|
return 0; |
|
} |
|
|
|
static struct spi_device_id st_nci_spi_id_table[] = { |
|
{ST_NCI_SPI_DRIVER_NAME, 0}, |
|
{} |
|
}; |
|
MODULE_DEVICE_TABLE(spi, st_nci_spi_id_table); |
|
|
|
static const struct acpi_device_id st_nci_spi_acpi_match[] = { |
|
{"SMO2101", 0}, |
|
{} |
|
}; |
|
MODULE_DEVICE_TABLE(acpi, st_nci_spi_acpi_match); |
|
|
|
static const struct of_device_id of_st_nci_spi_match[] = { |
|
{ .compatible = "st,st21nfcb-spi", }, |
|
{} |
|
}; |
|
MODULE_DEVICE_TABLE(of, of_st_nci_spi_match); |
|
|
|
static struct spi_driver st_nci_spi_driver = { |
|
.driver = { |
|
.name = ST_NCI_SPI_DRIVER_NAME, |
|
.of_match_table = of_match_ptr(of_st_nci_spi_match), |
|
.acpi_match_table = ACPI_PTR(st_nci_spi_acpi_match), |
|
}, |
|
.probe = st_nci_spi_probe, |
|
.id_table = st_nci_spi_id_table, |
|
.remove = st_nci_spi_remove, |
|
}; |
|
module_spi_driver(st_nci_spi_driver); |
|
|
|
MODULE_LICENSE("GPL"); |
|
MODULE_DESCRIPTION(DRIVER_DESC);
|
|
|