--- /dev/null
+/*
+ * I2C link layer for the NXP NCI driver
+ *
+ * Copyright (C) 2014 NXP Semiconductors All rights reserved.
+ *
+ * Authors: Clément Perrochaud <clement.perrochaud@nxp.com>
+ *
+ * Derived from PN544 device driver:
+ * Copyright (C) 2012 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * 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/>.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/nfc.h>
+#include <linux/of_gpio.h>
+#include <linux/of_irq.h>
+#include <linux/platform_data/nxp-nci.h>
+#include <linux/unaligned/access_ok.h>
+
+#include <net/nfc/nfc.h>
+
+#include "nxp-nci.h"
+
+#define NXP_NCI_I2C_DRIVER_NAME "nxp-nci_i2c"
+
+#define NXP_NCI_I2C_MAX_PAYLOAD 32
+
+struct nxp_nci_i2c_phy {
+ struct i2c_client *i2c_dev;
+ struct nci_dev *ndev;
+
+ unsigned int gpio_en;
+ unsigned int gpio_fw;
+
+ int hard_fault; /*
+ * < 0 if hardware error occurred (e.g. i2c err)
+ * and prevents normal operation.
+ */
+};
+
+static int nxp_nci_i2c_set_mode(void *phy_id,
+ enum nxp_nci_mode mode)
+{
+ struct nxp_nci_i2c_phy *phy = (struct nxp_nci_i2c_phy *) phy_id;
+
+ gpio_set_value(phy->gpio_fw, (mode == NXP_NCI_MODE_FW) ? 1 : 0);
+ gpio_set_value(phy->gpio_en, (mode != NXP_NCI_MODE_COLD) ? 1 : 0);
+ usleep_range(10000, 15000);
+
+ if (mode == NXP_NCI_MODE_COLD)
+ phy->hard_fault = 0;
+
+ return 0;
+}
+
+static int nxp_nci_i2c_write(void *phy_id, struct sk_buff *skb)
+{
+ int r;
+ struct nxp_nci_i2c_phy *phy = phy_id;
+ struct i2c_client *client = phy->i2c_dev;
+
+ if (phy->hard_fault != 0)
+ return phy->hard_fault;
+
+ r = i2c_master_send(client, skb->data, skb->len);
+ if (r == -EREMOTEIO) {
+ /* Retry, chip was in standby */
+ usleep_range(110000, 120000);
+ r = i2c_master_send(client, skb->data, skb->len);
+ }
+
+ if (r < 0) {
+ nfc_err(&client->dev, "Error %d on I2C send\n", r);
+ } else if (r != skb->len) {
+ nfc_err(&client->dev,
+ "Invalid length sent: %u (expected %u)\n",
+ r, skb->len);
+ r = -EREMOTEIO;
+ } else {
+ /* Success but return 0 and not number of bytes */
+ r = 0;
+ }
+
+ return r;
+}
+
+static struct nxp_nci_phy_ops i2c_phy_ops = {
+ .set_mode = nxp_nci_i2c_set_mode,
+ .write = nxp_nci_i2c_write,
+};
+
+static int nxp_nci_i2c_fw_read(struct nxp_nci_i2c_phy *phy,
+ struct sk_buff **skb)
+{
+ struct i2c_client *client = phy->i2c_dev;
+ u16 header;
+ size_t frame_len;
+ int r;
+
+ r = i2c_master_recv(client, (u8 *) &header, NXP_NCI_FW_HDR_LEN);
+ if (r < 0) {
+ goto fw_read_exit;
+ } else if (r != NXP_NCI_FW_HDR_LEN) {
+ nfc_err(&client->dev, "Incorrect header length: %u\n", r);
+ r = -EBADMSG;
+ goto fw_read_exit;
+ }
+
+ frame_len = (get_unaligned_be16(&header) & NXP_NCI_FW_FRAME_LEN_MASK) +
+ NXP_NCI_FW_CRC_LEN;
+
+ *skb = alloc_skb(NXP_NCI_FW_HDR_LEN + frame_len, GFP_KERNEL);
+ if (*skb == NULL) {
+ r = -ENOMEM;
+ goto fw_read_exit;
+ }
+
+ memcpy(skb_put(*skb, NXP_NCI_FW_HDR_LEN), &header, NXP_NCI_FW_HDR_LEN);
+
+ r = i2c_master_recv(client, skb_put(*skb, frame_len), frame_len);
+ if (r != frame_len) {
+ nfc_err(&client->dev,
+ "Invalid frame length: %u (expected %zu)\n",
+ r, frame_len);
+ r = -EBADMSG;
+ goto fw_read_exit_free_skb;
+ }
+
+ return 0;
+
+fw_read_exit_free_skb:
+ kfree_skb(*skb);
+fw_read_exit:
+ return r;
+}
+
+static int nxp_nci_i2c_nci_read(struct nxp_nci_i2c_phy *phy,
+ struct sk_buff **skb)
+{
+ struct nci_ctrl_hdr header; /* May actually be a data header */
+ struct i2c_client *client = phy->i2c_dev;
+ int r;
+
+ r = i2c_master_recv(client, (u8 *) &header, NCI_CTRL_HDR_SIZE);
+ if (r < 0) {
+ goto nci_read_exit;
+ } else if (r != NCI_CTRL_HDR_SIZE) {
+ nfc_err(&client->dev, "Incorrect header length: %u\n", r);
+ r = -EBADMSG;
+ goto nci_read_exit;
+ }
+
+ *skb = alloc_skb(NCI_CTRL_HDR_SIZE + header.plen, GFP_KERNEL);
+ if (*skb == NULL) {
+ r = -ENOMEM;
+ goto nci_read_exit;
+ }
+
+ memcpy(skb_put(*skb, NCI_CTRL_HDR_SIZE), (void *) &header,
+ NCI_CTRL_HDR_SIZE);
+
+ r = i2c_master_recv(client, skb_put(*skb, header.plen), header.plen);
+ if (r != header.plen) {
+ nfc_err(&client->dev,
+ "Invalid frame payload length: %u (expected %u)\n",
+ r, header.plen);
+ r = -EBADMSG;
+ goto nci_read_exit_free_skb;
+ }
+
+ return 0;
+
+nci_read_exit_free_skb:
+ kfree_skb(*skb);
+nci_read_exit:
+ return r;
+}
+
+static irqreturn_t nxp_nci_i2c_irq_thread_fn(int irq, void *phy_id)
+{
+ struct nxp_nci_i2c_phy *phy = phy_id;
+ struct i2c_client *client;
+ struct nxp_nci_info *info;
+
+ struct sk_buff *skb = NULL;
+ int r = 0;
+
+ if (!phy || !phy->ndev)
+ goto exit_irq_none;
+
+ client = phy->i2c_dev;
+
+ if (!client || irq != client->irq)
+ goto exit_irq_none;
+
+ info = nci_get_drvdata(phy->ndev);
+
+ if (!info)
+ goto exit_irq_none;
+
+ mutex_lock(&info->info_lock);
+
+ if (phy->hard_fault != 0)
+ goto exit_irq_handled;
+
+ switch (info->mode) {
+ case NXP_NCI_MODE_NCI:
+ r = nxp_nci_i2c_nci_read(phy, &skb);
+ break;
+ case NXP_NCI_MODE_FW:
+ r = nxp_nci_i2c_fw_read(phy, &skb);
+ break;
+ case NXP_NCI_MODE_COLD:
+ r = -EREMOTEIO;
+ break;
+ }
+
+ if (r == -EREMOTEIO) {
+ phy->hard_fault = r;
+ skb = NULL;
+ } else if (r < 0) {
+ nfc_err(&client->dev, "Read failed with error %d\n", r);
+ goto exit_irq_handled;
+ }
+
+ switch (info->mode) {
+ case NXP_NCI_MODE_NCI:
+ nci_recv_frame(phy->ndev, skb);
+ break;
+ case NXP_NCI_MODE_FW:
+ nxp_nci_fw_recv_frame(phy->ndev, skb);
+ break;
+ case NXP_NCI_MODE_COLD:
+ break;
+ }
+
+exit_irq_handled:
+ mutex_unlock(&info->info_lock);
+ return IRQ_HANDLED;
+exit_irq_none:
+ WARN_ON_ONCE(1);
+ return IRQ_NONE;
+}
+
+#ifdef CONFIG_OF
+
+static int nxp_nci_i2c_parse_devtree(struct i2c_client *client)
+{
+ struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client);
+ struct device_node *pp;
+ int r;
+
+ pp = client->dev.of_node;
+ if (!pp)
+ return -ENODEV;
+
+ r = of_get_named_gpio(pp, "enable-gpios", 0);
+ if (r == -EPROBE_DEFER)
+ r = of_get_named_gpio(pp, "enable-gpios", 0);
+ if (r < 0) {
+ nfc_err(&client->dev, "Failed to get EN gpio, error: %d\n", r);
+ return r;
+ }
+ phy->gpio_en = r;
+
+ r = of_get_named_gpio(pp, "firmware-gpios", 0);
+ if (r == -EPROBE_DEFER)
+ r = of_get_named_gpio(pp, "firmware-gpios", 0);
+ if (r < 0) {
+ nfc_err(&client->dev, "Failed to get FW gpio, error: %d\n", r);
+ return r;
+ }
+ phy->gpio_fw = r;
+
+ r = irq_of_parse_and_map(pp, 0);
+ if (r < 0) {
+ nfc_err(&client->dev, "Unable to get irq, error: %d\n", r);
+ return r;
+ }
+ client->irq = r;
+
+ return 0;
+}
+
+#else
+
+static int nxp_nci_i2c_parse_devtree(struct i2c_client *client)
+{
+ return -ENODEV;
+}
+
+#endif
+
+static int nxp_nci_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct nxp_nci_i2c_phy *phy;
+ struct nxp_nci_nfc_platform_data *pdata;
+ int r;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ nfc_err(&client->dev, "Need I2C_FUNC_I2C\n");
+ r = -ENODEV;
+ goto probe_exit;
+ }
+
+ phy = devm_kzalloc(&client->dev, sizeof(struct nxp_nci_i2c_phy),
+ GFP_KERNEL);
+ if (!phy) {
+ r = -ENOMEM;
+ goto probe_exit;
+ }
+
+ phy->i2c_dev = client;
+ i2c_set_clientdata(client, phy);
+
+ pdata = client->dev.platform_data;
+
+ if (!pdata && client->dev.of_node) {
+ r = nxp_nci_i2c_parse_devtree(client);
+ if (r < 0) {
+ nfc_err(&client->dev, "Failed to get DT data\n");
+ goto probe_exit;
+ }
+ } else if (pdata) {
+ phy->gpio_en = pdata->gpio_en;
+ phy->gpio_fw = pdata->gpio_fw;
+ client->irq = pdata->irq;
+ } else {
+ nfc_err(&client->dev, "No platform data\n");
+ r = -EINVAL;
+ goto probe_exit;
+ }
+
+ r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_en,
+ GPIOF_OUT_INIT_LOW, "nxp_nci_en");
+ if (r < 0)
+ goto probe_exit;
+
+ r = devm_gpio_request_one(&phy->i2c_dev->dev, phy->gpio_fw,
+ GPIOF_OUT_INIT_LOW, "nxp_nci_fw");
+ if (r < 0)
+ goto probe_exit;
+
+ r = nxp_nci_probe(phy, &client->dev, &i2c_phy_ops,
+ NXP_NCI_I2C_MAX_PAYLOAD, &phy->ndev);
+ if (r < 0)
+ goto probe_exit;
+
+ r = request_threaded_irq(client->irq, NULL,
+ nxp_nci_i2c_irq_thread_fn,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ NXP_NCI_I2C_DRIVER_NAME, phy);
+ if (r < 0)
+ nfc_err(&client->dev, "Unable to register IRQ handler\n");
+
+probe_exit:
+ return r;
+}
+
+static int nxp_nci_i2c_remove(struct i2c_client *client)
+{
+ struct nxp_nci_i2c_phy *phy = i2c_get_clientdata(client);
+
+ nxp_nci_remove(phy->ndev);
+ free_irq(client->irq, phy);
+
+ return 0;
+}
+
+static struct i2c_device_id nxp_nci_i2c_id_table[] = {
+ {"nxp-nci_i2c", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, nxp_nci_i2c_id_table);
+
+static const struct of_device_id of_nxp_nci_i2c_match[] = {
+ { .compatible = "nxp,nxp-nci-i2c", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, of_nxp_nci_i2c_match);
+
+static struct i2c_driver nxp_nci_i2c_driver = {
+ .driver = {
+ .name = NXP_NCI_I2C_DRIVER_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(of_nxp_nci_i2c_match),
+ },
+ .probe = nxp_nci_i2c_probe,
+ .id_table = nxp_nci_i2c_id_table,
+ .remove = nxp_nci_i2c_remove,
+};
+
+module_i2c_driver(nxp_nci_i2c_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("I2C driver for NXP NCI NFC controllers");
+MODULE_AUTHOR("Clément Perrochaud <clement.perrochaud@nxp.com>");
projects / openwrt / staging / blogic.git / commitdiff