drivers/nfc/nfcmrvl/i2c.c - linux - Git at Google

 /**
  * 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");
	/**
	* 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");