Commit 6be88670 authored by Clément Perrochaud's avatar Clément Perrochaud Committed by Samuel Ortiz

NFC: nxp-nci_i2c: Add I2C support to NXP NCI driver

Add a module to the NXP-NCI driver to support NFC controllers with an
I2C control interface, such as the NPC100.
Signed-off-by: default avatarClément Perrochaud <cleme[email protected]>
Signed-off-by: default avatarSamuel Ortiz <[email protected]>
parent dece4585
* NXP Semiconductors NXP NCI NFC Controllers
Required properties:
- compatible: Should be "nxp,nxp-nci-i2c".
- clock-frequency: I²C work frequency.
- reg: address on the bus
- interrupt-parent: phandle for the interrupt gpio controller
- interrupts: GPIO interrupt to which the chip is connected
- enable-gpios: Output GPIO pin used for enabling/disabling the chip
- firmware-gpios: Output GPIO pin used to enter firmware download mode
Optional SoC Specific Properties:
- pinctrl-names: Contains only one value - "default".
- pintctrl-0: Specifies the pin control groups used for this controller.
Example (for ARM-based BeagleBone with NPC100 NFC controller on I2C2):
&i2c2 {
status = "okay";
npc100: [email protected] {
compatible = "nxp,nxp-nci-i2c";
reg = <0x29>;
clock-frequency = <100000>;
interrupt-parent = <&gpio1>;
interrupts = <29 GPIO_ACTIVE_HIGH>;
enable-gpios = <&gpio0 30 GPIO_ACTIVE_HIGH>;
firmware-gpios = <&gpio0 31 GPIO_ACTIVE_HIGH>;
};
};
......@@ -11,3 +11,15 @@ config NFC_NXP_NCI
To compile this driver as a module, choose m here. The module will
be called nxp_nci.
Say N if unsure.
config NFC_NXP_NCI_I2C
tristate "NXP-NCI I2C support"
depends on NFC_NXP_NCI && I2C
---help---
This module adds support for an I2C interface to the NXP NCI
chips.
Select this if your platform is using the I2C bus.
To compile this driver as a module, choose m here. The module will
be called nxp_nci_i2c.
Say Y if unsure.
......@@ -3,7 +3,9 @@
#
nxp-nci-objs = core.o firmware.o
nxp-nci_i2c-objs = i2c.o
obj-$(CONFIG_NFC_NXP_NCI) += nxp-nci.o
obj-$(CONFIG_NFC_NXP_NCI_I2C) += nxp-nci_i2c.o
ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG
/*
* I2C link layer for the NXP NCI driver
*
* Copyright (C) 2014 NXP Semiconductors All rights reserved.
*
* Authors: Clément Perrochaud <[email protected]>
*
* Derived from PN544 device driver:
* Copyright (C) 2012 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/miscdevice.h>
#include <linux/module.h>
#include <linux/nfc.h>
#include <linux/of_gpio.h>
#include <linux/of_irq.h>
#include <linux/platform_data/nxp-nci.h>
#include <linux/unaligned/access_ok.h>
#include <net/nfc/nfc.h>
#include "nxp-nci.h"
#define NXP_NCI_I2C_DRIVER_NAME "nxp-nci_i2c"
#define NXP_NCI_I2C_MAX_PAYLOAD 32
struct nxp_nci_i2c_phy {
struct i2c_client *i2c_dev;
struct nci_dev *ndev;
unsigned int gpio_en;
unsigned int gpio_fw;
int hard_fault; /*
* < 0 if hardware error occurred (e.g. i2c err)
* and prevents normal operation.
*/
};
static int nxp_nci_i2c_set_mode(void *phy_id,
enum nxp_nci_mode mode)
{
struct nxp_nci_i2c_phy *phy = (struct nxp_nci_i2c_phy *) phy_id;
gpio_set_value(phy->gpio_fw, (mode == NXP_NCI_MODE_FW) ? 1 : 0);
gpio_set_value(phy->gpio_en, (mode != NXP_NCI_MODE_COLD) ? 1 : 0);
usleep_range(10000, 15000);
if (mode == NXP_NCI_MODE_COLD)
phy->hard_fault = 0;
return 0;
}
static int nxp_nci_i2c_write(void *phy_id, struct sk_buff *skb)
{
int r;
struct nxp_nci_i2c_phy *phy = phy_id;
struct i2c_client *client = phy->i2c_dev;
if (phy->hard_fault != 0)
return phy->hard_fault;
r = i2c_master_send(client, skb->data, skb->len);
if (r == -EREMOTEIO) {
/* Retry, chip was in standby */
usleep_range(110000, 120000);
r = i2c_master_send(client, skb->data, skb->len);
}
if (r < 0) {
nfc_err(&client->dev, "Error %d on I2C send\n", r);
} else if (r != skb->len) {
nfc_err(&client->dev,
"Invalid length sent: %u (expected %u)\n",
r, skb->len);
r = -EREMOTEIO;
} else {
/* Success but return 0 and not number of bytes */
r = 0;
}
return r;
}
static struct nxp_nci_phy_ops i2c_phy_ops = {
.set_mode = nxp_nci_i2c_set_mode,
.write = nxp_nci_i2c_write,
};
static int nxp_nci_i2c_fw_read(struct nxp_nci_i2c_phy *phy,
struct sk_buff **skb)
{
struct i2c_client *client = phy->i2c_dev;
u16 header;
size_t frame_len;
int r;
r = i2c_master_recv(client, (u8 *) &header, NXP_NCI_FW_HDR_LEN);
if (r < 0) {
goto fw_read_exit;
} else if (r != NXP_NCI_FW_HDR_LEN) {
nfc_err(&client->dev, "Incorrect header length: %u\n", r);
r = -EBADMSG;
goto fw_read_exit;
}
frame_len = (get_unaligned_be16(&header) & NXP_NCI_FW_FRAME_LEN_MASK) +
NXP_NCI_FW_CRC_LEN;
*skb = alloc_skb(NXP_NCI_FW_HDR_LEN + frame_len, GFP_KERNEL);
if (*skb == NULL) {
r = -ENOMEM;
goto fw_read_exit;
}
memcpy(skb_put(*skb, NXP_NCI_FW_HDR_LEN), &header, NXP_NCI_FW_HDR_LEN);
r = i2c_master_recv(client, skb_put(*skb, frame_len), frame_len);
if (r != frame_len) {
nfc_err(&client->dev,
"Invalid frame length: %u (expected %zu)\n",
r, frame_len);
r = -EBADMSG;
goto fw_read_exit_free_skb;
}
return 0;
fw_read_exit_free_skb:
kfree_skb(*skb);
fw_read_exit:
return r;
}
static int nxp_nci_i2c_nci_read(struct nxp_nci_i2c_phy *phy,
struct sk_buff **skb)
{
struct nci_ctrl_hdr header; /* May actually be a data header */
struct i2c_client *client = phy->i2c_dev;
int r;
r = i2c_master_recv(client, (u8 *) &header, NCI_CTRL_HDR_SIZE);
if (r < 0) {
goto nci_read_exit;
} else if (r != NCI_CTRL_HDR_SIZE) {
nfc_err(&client->dev, "Incorrect header length: %u\n", r);
r = -EBADMSG;
goto nci_read_exit;
}
*skb = alloc_skb(NCI_CTRL_HDR_SIZE + header.plen, GFP_KERNEL);
if (*skb == NULL) {
r = -ENOMEM;
goto nci_read_exit;
}
memcpy(skb_put(*skb, NCI_CTRL_HDR_SIZE), (void *) &header,
NCI_CTRL_HDR_SIZE);
r = i2c_master_recv(client, skb_put(*skb, header.plen), header.plen);
if (r != header.plen) {
nfc_err(&client->dev,
"Invalid frame payload length: %u (expected %u)\n",
r, header.plen);
r = -EBADMSG;
goto nci_read_exit_free_skb;
}
return 0;
nci_read_exit_free_skb:
kfree_skb(*skb);
nci_read_exit:
return r;
}
static irqreturn_t nxp_nci_i2c_irq_thread_fn(int irq, void *phy_id)
{
struct nxp_nci_i2c_phy *phy = phy_id;
struct i2c_client *client;
struct nxp_nci_info *info;
struct sk_buff *skb = NULL;
int r = 0;
if (!phy || !phy->ndev)
goto exit_irq_none;
client = phy->i2c_dev;
if (!client || irq != client->irq)
goto exit_irq_none;
info = nci_get_drvdata(phy->ndev);
if (!info)
goto exit_irq_none;
mutex_lock(&info->info_lock);
if (phy->hard_fault != 0)
goto exit_irq_handled;
switch (info->mode) {
case NXP_NCI_MODE_NCI:
r = nxp_nci_i2c_nci_read(phy, &skb);
break;
case NXP_NCI_MODE_FW:
r = nxp_nci_i2c_fw_read(phy, &skb);
break;
case NXP_NCI_MODE_COLD:
r = -EREMOTEIO;
break;
}
if (r == -EREMOTEIO) {
phy->hard_fault = r;
skb = NULL;
} else if (r < 0) {
nfc_err(&client->dev, "Read failed with error %d\n", r);
goto exit_irq_handled;
}
switch (info->mode) {
case NXP_NCI_MODE_NCI:
nci_recv_frame(phy->ndev, skb);
break;
case NXP_NCI_MODE_FW:
nxp_nci_fw_recv_frame(phy->ndev, skb);
break;
case NXP_NCI_MODE_COLD:
break;
}
exit_irq_handled:
mutex_unlock(&info->info_lock);
return IRQ_HANDLED;
exit_irq_none:
WARN_ON_ONCE(1);
return IRQ_NONE;
}
#ifdef CONFIG_OF
static int nxp_nci_i2c_parse_devtree(struct i2c_client *client)
{
struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client);
struct device_node *pp;
int r;
pp = client->dev.of_node;
if (!pp)
return -ENODEV;
r = of_get_named_gpio(pp, "enable-gpios", 0);
if (r == -EPROBE_DEFER)
r = of_get_named_gpio(pp, "enable-gpios", 0);
if (r < 0) {
nfc_err(&client->dev, "Failed to get EN gpio, error: %d\n", r);
return r;
}
phy->gpio_en = r;
r = of_get_named_gpio(pp, "firmware-gpios", 0);
if (r == -EPROBE_DEFER)
r = of_get_named_gpio(pp, "firmware-gpios", 0);
if (r < 0) {
nfc_err(&client->dev, "Failed to get FW gpio, error: %d\n", r);
return r;
}
phy->gpio_fw = r;
r = irq_of_parse_and_map(pp, 0);
if (r < 0) {
nfc_err(&client->dev, "Unable to get irq, error: %d\n", r);
return r;
}
client->irq = r;
return 0;
}
#else
static int nxp_nci_i2c_parse_devtree(struct i2c_client *client)
{
return -ENODEV;
}
#endif
static int nxp_nci_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct nxp_nci_i2c_phy *phy;
struct nxp_nci_nfc_platform_data *pdata;
int r;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
r = -ENODEV;
goto probe_exit;
}
phy = devm_kzalloc(&client->dev, sizeof(struct nxp_nci_i2c_phy),
GFP_KERNEL);
if (!phy) {
r = -ENOMEM;
goto probe_exit;
}
phy->i2c_dev = client;
i2c_set_clientdata(client, phy);
pdata = client->dev.platform_data;
if (!pdata && client->dev.of_node) {
r = nxp_nci_i2c_parse_devtree(client);
if (r < 0) {
nfc_err(&client->dev, "Failed to get DT data\n");
goto probe_exit;
}
} else if (pdata) {
phy->gpio_en = pdata->gpio_en;
phy->gpio_fw = pdata->gpio_fw;
client->irq = pdata->irq;
} else {
nfc_err(&client->dev, "No platform data\n");
r = -EINVAL;
goto probe_exit;
}
r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_en,
GPIOF_OUT_INIT_LOW, "nxp_nci_en");
if (r < 0)
goto probe_exit;
r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_fw,
GPIOF_OUT_INIT_LOW, "nxp_nci_fw");
if (r < 0)
goto probe_exit;
r = nxp_nci_probe(phy, &client->dev, &i2c_phy_ops,
NXP_NCI_I2C_MAX_PAYLOAD, &phy->ndev);
if (r < 0)
goto probe_exit;
r = request_threaded_irq(client->irq, NULL,
nxp_nci_i2c_irq_thread_fn,
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
NXP_NCI_I2C_DRIVER_NAME, phy);
if (r < 0)
nfc_err(&client->dev, "Unable to register IRQ handler\n");
probe_exit:
return r;
}
static int nxp_nci_i2c_remove(struct i2c_client *client)
{
struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client);
nxp_nci_remove(phy->ndev);
free_irq(client->irq, phy);
return 0;
}
static struct i2c_device_id nxp_nci_i2c_id_table[] = {
{"nxp-nci_i2c", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, nxp_nci_i2c_id_table);
static const struct of_device_id of_nxp_nci_i2c_match[] = {
{ .compatible = "nxp,nxp-nci-i2c", },
{},
};
MODULE_DEVICE_TABLE(of, of_nxp_nci_i2c_match);
static struct i2c_driver nxp_nci_i2c_driver = {
.driver = {
.name = NXP_NCI_I2C_DRIVER_NAME,
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(of_nxp_nci_i2c_match),
},
.probe = nxp_nci_i2c_probe,
.id_table = nxp_nci_i2c_id_table,
.remove = nxp_nci_i2c_remove,
};
module_i2c_driver(nxp_nci_i2c_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("I2C driver for NXP NCI NFC controllers");
MODULE_AUTHOR("Clément Perrochaud <[email protected]>");
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