src/kernel/linux/v4.14/drivers/nfc/pn533/i2c.c - T103 - Gitiles

 /*
  * Driver for NXP PN533 NFC Chip - I2C transport layer
  *
  * Copyright (C) 2011 Instituto Nokia de Tecnologia
  * Copyright (C) 2012-2013 Tieto Poland
  * Copyright (C) 2016 HALE electronic
  *
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
  * 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/>.
  */

 #include <linux/device.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/i2c.h>
 #include <linux/nfc.h>
 #include <linux/netdevice.h>
 #include <linux/interrupt.h>
 #include <net/nfc/nfc.h>
 #include "pn533.h"

 #define VERSION "0.1"

 #define PN533_I2C_DRIVER_NAME "pn533_i2c"

 struct pn533_i2c_phy {
 	struct i2c_client *i2c_dev;
 	struct pn533 *priv;

 	bool aborted;

 	int hard_fault;		/*
 				 * < 0 if hardware error occurred (e.g. i2c err)
 				 * and prevents normal operation.
 				 */
 };

 static int pn533_i2c_send_ack(struct pn533 *dev, gfp_t flags)
 {
 	struct pn533_i2c_phy *phy = dev->phy;
 	struct i2c_client *client = phy->i2c_dev;
 	static const u8 ack[6] = {0x00, 0x00, 0xff, 0x00, 0xff, 0x00};
 	/* spec 6.2.1.3:  Preamble, SoPC (2), ACK Code (2), Postamble */
 	int rc;

 	rc = i2c_master_send(client, ack, 6);

 	return rc;
 }

 static int pn533_i2c_send_frame(struct pn533 *dev,
 				struct sk_buff *out)
 {
 	struct pn533_i2c_phy *phy = dev->phy;
 	struct i2c_client *client = phy->i2c_dev;
 	int rc;

 	if (phy->hard_fault != 0)
 		return phy->hard_fault;

 	if (phy->priv == NULL)
 		phy->priv = dev;

 	phy->aborted = false;

 	print_hex_dump_debug("PN533_i2c TX: ", DUMP_PREFIX_NONE, 16, 1,
 			     out->data, out->len, false);

 	rc = i2c_master_send(client, out->data, out->len);

 	if (rc == -EREMOTEIO) { /* Retry, chip was in power down */
 		usleep_range(6000, 10000);
 		rc = i2c_master_send(client, out->data, out->len);
 	}

 	if (rc >= 0) {
 		if (rc != out->len)
 			rc = -EREMOTEIO;
 		else
 			rc = 0;
 	}

 	return rc;
 }

 static void pn533_i2c_abort_cmd(struct pn533 *dev, gfp_t flags)
 {
 	struct pn533_i2c_phy *phy = dev->phy;

 	phy->aborted = true;

 	/* An ack will cancel the last issued command */
 	pn533_i2c_send_ack(dev, flags);

 	/* schedule cmd_complete_work to finish current command execution */
 	pn533_recv_frame(phy->priv, NULL, -ENOENT);
 }

 static int pn533_i2c_read(struct pn533_i2c_phy *phy, struct sk_buff **skb)
 {
 	struct i2c_client *client = phy->i2c_dev;
 	int len = PN533_EXT_FRAME_HEADER_LEN +
 		  PN533_STD_FRAME_MAX_PAYLOAD_LEN +
 		  PN533_STD_FRAME_TAIL_LEN + 1;
 	int r;

 	*skb = alloc_skb(len, GFP_KERNEL);
 	if (*skb == NULL)
 		return -ENOMEM;

 	r = i2c_master_recv(client, skb_put(*skb, len), len);
 	if (r != len) {
 		nfc_err(&client->dev, "cannot read. r=%d len=%d\n", r, len);
 		kfree_skb(*skb);
 		return -EREMOTEIO;
 	}

 	if (!((*skb)->data[0] & 0x01)) {
 		nfc_err(&client->dev, "READY flag not set");
 		kfree_skb(*skb);
 		return -EBUSY;
 	}

 	/* remove READY byte */
 	skb_pull(*skb, 1);
 	/* trim to frame size */
 	skb_trim(*skb, phy->priv->ops->rx_frame_size((*skb)->data));

 	return 0;
 }

 static irqreturn_t pn533_i2c_irq_thread_fn(int irq, void *data)
 {
 	struct pn533_i2c_phy *phy = data;
 	struct i2c_client *client;
 	struct sk_buff *skb = NULL;
 	int r;

 	if (!phy || irq != phy->i2c_dev->irq) {
 		WARN_ON_ONCE(1);
 		return IRQ_NONE;
 	}

 	client = phy->i2c_dev;
 	dev_dbg(&client->dev, "IRQ\n");

 	if (phy->hard_fault != 0)
 		return IRQ_HANDLED;

 	r = pn533_i2c_read(phy, &skb);
 	if (r == -EREMOTEIO) {
 		phy->hard_fault = r;

 		pn533_recv_frame(phy->priv, NULL, -EREMOTEIO);

 		return IRQ_HANDLED;
 	} else if ((r == -ENOMEM) || (r == -EBADMSG) || (r == -EBUSY)) {
 		return IRQ_HANDLED;
 	}

 	if (!phy->aborted)
 		pn533_recv_frame(phy->priv, skb, 0);

 	return IRQ_HANDLED;
 }

 static struct pn533_phy_ops i2c_phy_ops = {
 	.send_frame = pn533_i2c_send_frame,
 	.send_ack = pn533_i2c_send_ack,
 	.abort_cmd = pn533_i2c_abort_cmd,
 };


 static int pn533_i2c_probe(struct i2c_client *client,
 			       const struct i2c_device_id *id)
 {
 	struct pn533_i2c_phy *phy;
 	struct pn533 *priv;
 	int r = 0;

 	dev_dbg(&client->dev, "%s\n", __func__);
 	dev_dbg(&client->dev, "IRQ: %d\n", client->irq);

 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 		nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
 		return -ENODEV;
 	}

 	phy = devm_kzalloc(&client->dev, sizeof(struct pn533_i2c_phy),
 			   GFP_KERNEL);
 	if (!phy)
 		return -ENOMEM;

 	phy->i2c_dev = client;
 	i2c_set_clientdata(client, phy);

 	priv = pn533_register_device(PN533_DEVICE_PN532,
 				     PN533_NO_TYPE_B_PROTOCOLS,
 				     PN533_PROTO_REQ_ACK_RESP,
 				     phy, &i2c_phy_ops, NULL,
 				     &phy->i2c_dev->dev,
 				     &client->dev);

 	if (IS_ERR(priv)) {
 		r = PTR_ERR(priv);
 		return r;
 	}

 	phy->priv = priv;

 	r = request_threaded_irq(client->irq, NULL, pn533_i2c_irq_thread_fn,
 				IRQF_TRIGGER_FALLING |
 				IRQF_SHARED | IRQF_ONESHOT,
 				PN533_I2C_DRIVER_NAME, phy);
 	if (r < 0) {
 		nfc_err(&client->dev, "Unable to register IRQ handler\n");
 		goto irq_rqst_err;
 	}

 	r = pn533_finalize_setup(priv);
 	if (r)
 		goto fn_setup_err;

 	return 0;

 fn_setup_err:
 	free_irq(client->irq, phy);

 irq_rqst_err:
 	pn533_unregister_device(phy->priv);

 	return r;
 }

 static int pn533_i2c_remove(struct i2c_client *client)
 {
 	struct pn533_i2c_phy *phy = i2c_get_clientdata(client);

 	dev_dbg(&client->dev, "%s\n", __func__);

 	free_irq(client->irq, phy);

 	pn533_unregister_device(phy->priv);

 	return 0;
 }

 static const struct of_device_id of_pn533_i2c_match[] = {
 	{ .compatible = "nxp,pn533-i2c", },
 	{ .compatible = "nxp,pn532-i2c", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, of_pn533_i2c_match);

 static struct i2c_device_id pn533_i2c_id_table[] = {
 	{ PN533_I2C_DRIVER_NAME, 0 },
 	{}
 };
 MODULE_DEVICE_TABLE(i2c, pn533_i2c_id_table);

 static struct i2c_driver pn533_i2c_driver = {
 	.driver = {
 		   .name = PN533_I2C_DRIVER_NAME,
 		   .owner = THIS_MODULE,
 		   .of_match_table = of_match_ptr(of_pn533_i2c_match),
 		  },
 	.probe = pn533_i2c_probe,
 	.id_table = pn533_i2c_id_table,
 	.remove = pn533_i2c_remove,
 };

 module_i2c_driver(pn533_i2c_driver);

 MODULE_AUTHOR("Michael Thalmeier <michael.thalmeier@hale.at>");
 MODULE_DESCRIPTION("PN533 I2C driver ver " VERSION);
 MODULE_VERSION(VERSION);
 MODULE_LICENSE("GPL");
	/*
	* Driver for NXP PN533 NFC Chip - I2C transport layer
	*
	* Copyright (C) 2011 Instituto Nokia de Tecnologia
	* Copyright (C) 2012-2013 Tieto Poland
	* Copyright (C) 2016 HALE electronic
	*
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* 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/>.
	*/

	#include <linux/device.h>
	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/slab.h>
	#include <linux/i2c.h>
	#include <linux/nfc.h>
	#include <linux/netdevice.h>
	#include <linux/interrupt.h>
	#include <net/nfc/nfc.h>
	#include "pn533.h"

	#define VERSION "0.1"

	#define PN533_I2C_DRIVER_NAME "pn533_i2c"

	struct pn533_i2c_phy {
	struct i2c_client *i2c_dev;
	struct pn533 *priv;

	bool aborted;

	int hard_fault; /*
	* < 0 if hardware error occurred (e.g. i2c err)
	* and prevents normal operation.
	*/
	};

	static int pn533_i2c_send_ack(struct pn533 *dev, gfp_t flags)
	{
	struct pn533_i2c_phy *phy = dev->phy;
	struct i2c_client *client = phy->i2c_dev;
	static const u8 ack[6] = {0x00, 0x00, 0xff, 0x00, 0xff, 0x00};
	/* spec 6.2.1.3: Preamble, SoPC (2), ACK Code (2), Postamble */
	int rc;

	rc = i2c_master_send(client, ack, 6);

	return rc;
	}

	static int pn533_i2c_send_frame(struct pn533 *dev,
	struct sk_buff *out)
	{
	struct pn533_i2c_phy *phy = dev->phy;
	struct i2c_client *client = phy->i2c_dev;
	int rc;

	if (phy->hard_fault != 0)
	return phy->hard_fault;

	if (phy->priv == NULL)
	phy->priv = dev;

	phy->aborted = false;

	print_hex_dump_debug("PN533_i2c TX: ", DUMP_PREFIX_NONE, 16, 1,
	out->data, out->len, false);

	rc = i2c_master_send(client, out->data, out->len);

	if (rc == -EREMOTEIO) { /* Retry, chip was in power down */
	usleep_range(6000, 10000);
	rc = i2c_master_send(client, out->data, out->len);
	}

	if (rc >= 0) {
	if (rc != out->len)
	rc = -EREMOTEIO;
	else
	rc = 0;
	}

	return rc;
	}

	static void pn533_i2c_abort_cmd(struct pn533 *dev, gfp_t flags)
	{
	struct pn533_i2c_phy *phy = dev->phy;

	phy->aborted = true;

	/* An ack will cancel the last issued command */
	pn533_i2c_send_ack(dev, flags);

	/* schedule cmd_complete_work to finish current command execution */
	pn533_recv_frame(phy->priv, NULL, -ENOENT);
	}

	static int pn533_i2c_read(struct pn533_i2c_phy phy, struct sk_buff *skb)
	{
	struct i2c_client *client = phy->i2c_dev;
	int len = PN533_EXT_FRAME_HEADER_LEN +
	PN533_STD_FRAME_MAX_PAYLOAD_LEN +
	PN533_STD_FRAME_TAIL_LEN + 1;
	int r;

	*skb = alloc_skb(len, GFP_KERNEL);
	if (*skb == NULL)
	return -ENOMEM;

	r = i2c_master_recv(client, skb_put(*skb, len), len);
	if (r != len) {
	nfc_err(&client->dev, "cannot read. r=%d len=%d\n", r, len);
	kfree_skb(*skb);
	return -EREMOTEIO;
	}

	if (!((*skb)->data[0] & 0x01)) {
	nfc_err(&client->dev, "READY flag not set");
	kfree_skb(*skb);
	return -EBUSY;
	}

	/* remove READY byte */
	skb_pull(*skb, 1);
	/* trim to frame size */
	skb_trim(skb, phy->priv->ops->rx_frame_size((skb)->data));

	return 0;
	}

	static irqreturn_t pn533_i2c_irq_thread_fn(int irq, void *data)
	{
	struct pn533_i2c_phy *phy = data;
	struct i2c_client *client;
	struct sk_buff *skb = NULL;
	int r;

	if (!phy \|\| irq != phy->i2c_dev->irq) {
	WARN_ON_ONCE(1);
	return IRQ_NONE;
	}

	client = phy->i2c_dev;
	dev_dbg(&client->dev, "IRQ\n");

	if (phy->hard_fault != 0)
	return IRQ_HANDLED;

	r = pn533_i2c_read(phy, &skb);
	if (r == -EREMOTEIO) {
	phy->hard_fault = r;

	pn533_recv_frame(phy->priv, NULL, -EREMOTEIO);

	return IRQ_HANDLED;
	} else if ((r == -ENOMEM) \|\| (r == -EBADMSG) \|\| (r == -EBUSY)) {
	return IRQ_HANDLED;
	}

	if (!phy->aborted)
	pn533_recv_frame(phy->priv, skb, 0);

	return IRQ_HANDLED;
	}

	static struct pn533_phy_ops i2c_phy_ops = {
	.send_frame = pn533_i2c_send_frame,
	.send_ack = pn533_i2c_send_ack,
	.abort_cmd = pn533_i2c_abort_cmd,
	};


	static int pn533_i2c_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct pn533_i2c_phy *phy;
	struct pn533 *priv;
	int r = 0;

	dev_dbg(&client->dev, "%s\n", __func__);
	dev_dbg(&client->dev, "IRQ: %d\n", client->irq);

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
	nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
	return -ENODEV;
	}

	phy = devm_kzalloc(&client->dev, sizeof(struct pn533_i2c_phy),
	GFP_KERNEL);
	if (!phy)
	return -ENOMEM;

	phy->i2c_dev = client;
	i2c_set_clientdata(client, phy);

	priv = pn533_register_device(PN533_DEVICE_PN532,
	PN533_NO_TYPE_B_PROTOCOLS,
	PN533_PROTO_REQ_ACK_RESP,
	phy, &i2c_phy_ops, NULL,
	&phy->i2c_dev->dev,
	&client->dev);

	if (IS_ERR(priv)) {
	r = PTR_ERR(priv);
	return r;
	}

	phy->priv = priv;

	r = request_threaded_irq(client->irq, NULL, pn533_i2c_irq_thread_fn,
	IRQF_TRIGGER_FALLING \|
	IRQF_SHARED \| IRQF_ONESHOT,
	PN533_I2C_DRIVER_NAME, phy);
	if (r < 0) {
	nfc_err(&client->dev, "Unable to register IRQ handler\n");
	goto irq_rqst_err;
	}

	r = pn533_finalize_setup(priv);
	if (r)
	goto fn_setup_err;

	return 0;

	fn_setup_err:
	free_irq(client->irq, phy);

	irq_rqst_err:
	pn533_unregister_device(phy->priv);

	return r;
	}

	static int pn533_i2c_remove(struct i2c_client *client)
	{
	struct pn533_i2c_phy *phy = i2c_get_clientdata(client);

	dev_dbg(&client->dev, "%s\n", __func__);

	free_irq(client->irq, phy);

	pn533_unregister_device(phy->priv);

	return 0;
	}

	static const struct of_device_id of_pn533_i2c_match[] = {
	{ .compatible = "nxp,pn533-i2c", },
	{ .compatible = "nxp,pn532-i2c", },
	{},
	};
	MODULE_DEVICE_TABLE(of, of_pn533_i2c_match);

	static struct i2c_device_id pn533_i2c_id_table[] = {
	{ PN533_I2C_DRIVER_NAME, 0 },
	{}
	};
	MODULE_DEVICE_TABLE(i2c, pn533_i2c_id_table);

	static struct i2c_driver pn533_i2c_driver = {
	.driver = {
	.name = PN533_I2C_DRIVER_NAME,
	.owner = THIS_MODULE,
	.of_match_table = of_match_ptr(of_pn533_i2c_match),
	},
	.probe = pn533_i2c_probe,
	.id_table = pn533_i2c_id_table,
	.remove = pn533_i2c_remove,
	};

	module_i2c_driver(pn533_i2c_driver);

	MODULE_AUTHOR("Michael Thalmeier <michael.thalmeier@hale.at>");
	MODULE_DESCRIPTION("PN533 I2C driver ver " VERSION);
	MODULE_VERSION(VERSION);
	MODULE_LICENSE("GPL");