| /* |
| * 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"); |