i2c.c
/**
* Marvell NFC-over-I2C driver: I2C interface related functions
*
* Copyright (C) 2015, Marvell International Ltd.
*
* This software file (the "File") is distributed by Marvell International
* Ltd. under the terms of the GNU General Public License Version 2, June 1991
* (the "License"). You may use, redistribute and/or modify this File in
* accordance with the terms and conditions of the License, a copy of which
* is available on the worldwide web at
* http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
*
* THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
* IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
* ARE EXPRESSLY DISCLAIMED. The License provides additional details about
* this warranty disclaimer.
**/
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
#include <linux/pm_runtime.h>
#include <linux/nfc.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/of_irq.h>
#include <linux/of_gpio.h>
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
#include "nfcmrvl.h"
struct nfcmrvl_i2c_drv_data {
unsigned long flags;
struct device *dev;
struct i2c_client *i2c;
struct nfcmrvl_private *priv;
};
static int nfcmrvl_i2c_read(struct nfcmrvl_i2c_drv_data *drv_data,
struct sk_buff **skb)
{
int ret;
struct nci_ctrl_hdr nci_hdr;
/* Read NCI header to know the payload size */
ret = i2c_master_recv(drv_data->i2c, (u8 *)&nci_hdr, NCI_CTRL_HDR_SIZE);
if (ret != NCI_CTRL_HDR_SIZE) {
nfc_err(&drv_data->i2c->dev, "cannot read NCI header\n");
return -EBADMSG;
}
if (nci_hdr.plen > NCI_MAX_PAYLOAD_SIZE) {
nfc_err(&drv_data->i2c->dev, "invalid packet payload size\n");
return -EBADMSG;
}
*skb = nci_skb_alloc(drv_data->priv->ndev,
nci_hdr.plen + NCI_CTRL_HDR_SIZE, GFP_KERNEL);
if (!*skb)
return -ENOMEM;
/* Copy NCI header into the SKB */
skb_put_data(*skb, &nci_hdr, NCI_CTRL_HDR_SIZE);
if (nci_hdr.plen) {
/* Read the NCI payload */
ret = i2c_master_recv(drv_data->i2c,
skb_put(*skb, nci_hdr.plen),
nci_hdr.plen);
if (ret != nci_hdr.plen) {
nfc_err(&drv_data->i2c->dev,
"Invalid frame payload length: %u (expected %u)\n",
ret, nci_hdr.plen);
kfree_skb(*skb);
return -EBADMSG;
}
}
return 0;
}
static irqreturn_t nfcmrvl_i2c_int_irq_thread_fn(int irq, void *drv_data_ptr)
{
struct nfcmrvl_i2c_drv_data *drv_data = drv_data_ptr;
struct sk_buff *skb = NULL;
int ret;
if (!drv_data->priv)
return IRQ_HANDLED;
if (test_bit(NFCMRVL_PHY_ERROR, &drv_data->priv->flags))
return IRQ_HANDLED;
ret = nfcmrvl_i2c_read(drv_data, &skb);
switch (ret) {
case -EREMOTEIO:
set_bit(NFCMRVL_PHY_ERROR, &drv_data->priv->flags);
break;
case -ENOMEM:
case -EBADMSG:
nfc_err(&drv_data->i2c->dev, "read failed %d\n", ret);
break;
default:
if (nfcmrvl_nci_recv_frame(drv_data->priv, skb) < 0)
nfc_err(&drv_data->i2c->dev, "corrupted RX packet\n");
break;
}
return IRQ_HANDLED;
}
static int nfcmrvl_i2c_nci_open(struct nfcmrvl_private *priv)
{
struct nfcmrvl_i2c_drv_data *drv_data = priv->drv_data;
if (!drv_data)
return -ENODEV;
return 0;
}
static int nfcmrvl_i2c_nci_close(struct nfcmrvl_private *priv)
{
return 0;
}
static int nfcmrvl_i2c_nci_send(struct nfcmrvl_private *priv,
struct sk_buff *skb)
{
struct nfcmrvl_i2c_drv_data *drv_data = priv->drv_data;
int ret;
if (test_bit(NFCMRVL_PHY_ERROR, &priv->flags))
return -EREMOTEIO;
ret = i2c_master_send(drv_data->i2c, skb->data, skb->len);
/* Retry if chip was in standby */
if (ret == -EREMOTEIO) {
nfc_info(drv_data->dev, "chip may sleep, retry\n");
usleep_range(6000, 10000);
ret = i2c_master_send(drv_data->i2c, skb->data, skb->len);
}
if (ret >= 0) {
if (ret != skb->len) {
nfc_err(drv_data->dev,
"Invalid length sent: %u (expected %u)\n",
ret, skb->len);
ret = -EREMOTEIO;
} else
ret = 0;
kfree_skb(skb);
}
return ret;
}
static void nfcmrvl_i2c_nci_update_config(struct nfcmrvl_private *priv,
const void *param)
{
}
static struct nfcmrvl_if_ops i2c_ops = {
.nci_open = nfcmrvl_i2c_nci_open,
.nci_close = nfcmrvl_i2c_nci_close,
.nci_send = nfcmrvl_i2c_nci_send,
.nci_update_config = nfcmrvl_i2c_nci_update_config,
};
static int nfcmrvl_i2c_parse_dt(struct device_node *node,
struct nfcmrvl_platform_data *pdata)
{
int ret;
ret = nfcmrvl_parse_dt(node, pdata);
if (ret < 0) {
pr_err("Failed to get generic entries\n");
return ret;
}
if (of_find_property(node, "i2c-int-falling", NULL))
pdata->irq_polarity = IRQF_TRIGGER_FALLING;
else
pdata->irq_polarity = IRQF_TRIGGER_RISING;
ret = irq_of_parse_and_map(node, 0);
if (ret < 0) {
pr_err("Unable to get irq, error: %d\n", ret);
return ret;
}
pdata->irq = ret;
return 0;
}
static int nfcmrvl_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct nfcmrvl_i2c_drv_data *drv_data;
struct nfcmrvl_platform_data *pdata;
struct nfcmrvl_platform_data config;
int ret;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
return -ENODEV;
}
drv_data = devm_kzalloc(&client->dev, sizeof(*drv_data), GFP_KERNEL);
if (!drv_data)
return -ENOMEM;
drv_data->i2c = client;
drv_data->dev = &client->dev;
drv_data->priv = NULL;
i2c_set_clientdata(client, drv_data);
pdata = client->dev.platform_data;
if (!pdata && client->dev.of_node)
if (nfcmrvl_i2c_parse_dt(client->dev.of_node, &config) == 0)
pdata = &config;
if (!pdata)
return -EINVAL;
/* Request the read IRQ */
ret = devm_request_threaded_irq(&drv_data->i2c->dev, pdata->irq,
NULL, nfcmrvl_i2c_int_irq_thread_fn,
pdata->irq_polarity | IRQF_ONESHOT,
"nfcmrvl_i2c_int", drv_data);
if (ret < 0) {
nfc_err(&drv_data->i2c->dev,
"Unable to register IRQ handler\n");
return ret;
}
drv_data->priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_I2C,
drv_data, &i2c_ops,
&drv_data->i2c->dev, pdata);
if (IS_ERR(drv_data->priv))
return PTR_ERR(drv_data->priv);
drv_data->priv->support_fw_dnld = true;
return 0;
}
static int nfcmrvl_i2c_remove(struct i2c_client *client)
{
struct nfcmrvl_i2c_drv_data *drv_data = i2c_get_clientdata(client);
nfcmrvl_nci_unregister_dev(drv_data->priv);
return 0;
}
static const struct of_device_id of_nfcmrvl_i2c_match[] = {
{ .compatible = "marvell,nfc-i2c", },
{},
};
MODULE_DEVICE_TABLE(of, of_nfcmrvl_i2c_match);
static const struct i2c_device_id nfcmrvl_i2c_id_table[] = {
{ "nfcmrvl_i2c", 0 },
{}
};
MODULE_DEVICE_TABLE(i2c, nfcmrvl_i2c_id_table);
static struct i2c_driver nfcmrvl_i2c_driver = {
.probe = nfcmrvl_i2c_probe,
.id_table = nfcmrvl_i2c_id_table,
.remove = nfcmrvl_i2c_remove,
.driver = {
.name = "nfcmrvl_i2c",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(of_nfcmrvl_i2c_match),
},
};
module_i2c_driver(nfcmrvl_i2c_driver);
MODULE_AUTHOR("Marvell International Ltd.");
MODULE_DESCRIPTION("Marvell NFC-over-I2C driver");
MODULE_LICENSE("GPL v2");