/**
* Marvell NFC-over-SPI driver: SPI 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/pm_runtime.h>
#include <linux/nfc.h>
#include <linux/gpio.h>
#include <linux/of_irq.h>
#include <linux/of_gpio.h>
#include <net/nfc/nci.h>
#include <net/nfc/nci_core.h>
#include <linux/spi/spi.h>
#include "nfcmrvl.h"
#define SPI_WAIT_HANDSHAKE 1
struct nfcmrvl_spi_drv_data {
unsigned long flags;
struct spi_device *spi;
struct nci_spi *nci_spi;
struct completion handshake_completion;
struct nfcmrvl_private *priv;
};
static irqreturn_t nfcmrvl_spi_int_irq_thread_fn(int irq, void *drv_data_ptr)
{
struct nfcmrvl_spi_drv_data *drv_data = drv_data_ptr;
struct sk_buff *skb;
/*
* Special case where we are waiting for SPI_INT deassertion to start a
* transfer.
*/
if (test_and_clear_bit(SPI_WAIT_HANDSHAKE, &drv_data->flags)) {
complete(&drv_data->handshake_completion);
return IRQ_HANDLED;
}
/* Normal case, SPI_INT deasserted by slave to trigger a master read */
skb = nci_spi_read(drv_data->nci_spi);
if (!skb) {
nfc_err(&drv_data->spi->dev, "failed to read spi packet");
return IRQ_HANDLED;
}
if (nfcmrvl_nci_recv_frame(drv_data->priv, skb) < 0)
nfc_err(&drv_data->spi->dev, "corrupted RX packet");
return IRQ_HANDLED;
}
static int nfcmrvl_spi_nci_open(struct nfcmrvl_private *priv)
{
return 0;
}
static int nfcmrvl_spi_nci_close(struct nfcmrvl_private *priv)
{
return 0;
}
static int nfcmrvl_spi_nci_send(struct nfcmrvl_private *priv,
struct sk_buff *skb)
{
struct nfcmrvl_spi_drv_data *drv_data = priv->drv_data;
int err;
/* Reinit completion for slave handshake */
reinit_completion(&drv_data->handshake_completion);
set_bit(SPI_WAIT_HANDSHAKE, &drv_data->flags);
/*
* Append a dummy byte at the end of SPI frame. This is due to a
* specific DMA implementation in the controller
*/
skb_put(skb, 1);
/* Send the SPI packet */
err = nci_spi_send(drv_data->nci_spi, &drv_data->handshake_completion,
skb);
if (err)
nfc_err(priv->dev, "spi_send failed %d", err);
return err;
}
static void nfcmrvl_spi_nci_update_config(struct nfcmrvl_private *priv,
const void *param)
{
struct nfcmrvl_spi_drv_data *drv_data = priv->drv_data;
const struct nfcmrvl_fw_spi_config *config = param;
drv_data->nci_spi->xfer_speed_hz = config->clk;
}
static struct nfcmrvl_if_ops spi_ops = {
.nci_open = nfcmrvl_spi_nci_open,
.nci_close = nfcmrvl_spi_nci_close,
.nci_send = nfcmrvl_spi_nci_send,
.nci_update_config = nfcmrvl_spi_nci_update_config,
};
static int nfcmrvl_spi_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;
}
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_spi_probe(struct spi_device *spi)
{
struct nfcmrvl_platform_data *pdata;
struct nfcmrvl_platform_data config;
struct nfcmrvl_spi_drv_data *drv_data;
int ret = 0;
drv_data = devm_kzalloc(&spi->dev, sizeof(*drv_data), GFP_KERNEL);
if (!drv_data)
return -ENOMEM;
drv_data->spi = spi;
drv_data->priv = NULL;
spi_set_drvdata(spi, drv_data);
pdata = spi->dev.platform_data;
if (!pdata && spi->dev.of_node)
if (nfcmrvl_spi_parse_dt(spi->dev.of_node, &config) == 0)
pdata = &config;
if (!pdata)
return -EINVAL;
ret = devm_request_threaded_irq(&drv_data->spi->dev, pdata->irq,
NULL, nfcmrvl_spi_int_irq_thread_fn,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
"nfcmrvl_spi_int", drv_data);
if (ret < 0) {
nfc_err(&drv_data->spi->dev, "Unable to register IRQ handler");
return -ENODEV;
}
drv_data->priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_SPI,
drv_data, &spi_ops,
&drv_data->spi->dev,
pdata);
if (IS_ERR(drv_data->priv))
return PTR_ERR(drv_data->priv);
drv_data->priv->support_fw_dnld = true;
drv_data->nci_spi = nci_spi_allocate_spi(drv_data->spi, 0, 10,
drv_data->priv->ndev);
/* Init completion for slave handshake */
init_completion(&drv_data->handshake_completion);
return 0;
}
static int nfcmrvl_spi_remove(struct spi_device *spi)
{
struct nfcmrvl_spi_drv_data *drv_data = spi_get_drvdata(spi);
nfcmrvl_nci_unregister_dev(drv_data->priv);
return 0;
}
static const struct of_device_id of_nfcmrvl_spi_match[] = {
{ .compatible = "marvell,nfc-spi", },
{},
};
MODULE_DEVICE_TABLE(of, of_nfcmrvl_spi_match);
static const struct spi_device_id nfcmrvl_spi_id_table[] = {
{ "nfcmrvl_spi", 0 },
{ }
};
MODULE_DEVICE_TABLE(spi, nfcmrvl_spi_id_table);
static struct spi_driver nfcmrvl_spi_driver = {
.probe = nfcmrvl_spi_probe,
.remove = nfcmrvl_spi_remove,
.id_table = nfcmrvl_spi_id_table,
.driver = {
.name = "nfcmrvl_spi",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(of_nfcmrvl_spi_match),
},
};
module_spi_driver(nfcmrvl_spi_driver);
MODULE_AUTHOR("Marvell International Ltd.");
MODULE_DESCRIPTION("Marvell NFC-over-SPI driver");
MODULE_LICENSE("GPL v2");
