1 files changed, 400 insertions, 0 deletions

diff --git a/drivers/nfc/pn544.c b/drivers/nfc/pn544.c
new file mode 100644
index 00000000000..91216e465e1
--- /dev/null
+++ b/drivers/nfc/pn544.c
@@ -0,0 +1,400 @@
+/*
+ * Copyright (C) 2010 Trusted Logic S.A.
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/i2c.h>
+#include <linux/irq.h>
+#include <linux/jiffies.h>
+#include <linux/uaccess.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/miscdevice.h>
+#include <linux/spinlock.h>
+#include <linux/nfc/pn544.h>
+
+#define MAX_BUFFER_SIZE 512
+
+struct pn544_dev        {
+        wait_queue_head_t       read_wq;
+        struct mutex            read_mutex;
+        struct i2c_client       *client;
+        struct miscdevice       pn544_device;
+        unsigned int            ven_gpio;
+        unsigned int            firm_gpio;
+        unsigned int            irq_gpio;
+        bool                    irq_enabled;
+        spinlock_t              irq_enabled_lock;
+};
+
+static void pn544_disable_irq(struct pn544_dev *pn544_dev)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&pn544_dev->irq_enabled_lock, flags);
+        if (pn544_dev->irq_enabled) {
+                disable_irq_nosync(pn544_dev->client->irq);
+                pn544_dev->irq_enabled = false;
+        }
+        spin_unlock_irqrestore(&pn544_dev->irq_enabled_lock, flags);
+}
+
+static irqreturn_t pn544_dev_irq_handler(int irq, void *dev_id)
+{
+        struct pn544_dev *pn544_dev = dev_id;
+
+        pn544_disable_irq(pn544_dev);
+
+        /* Wake up waiting readers */
+        wake_up(&pn544_dev->read_wq);
+
+        return IRQ_HANDLED;
+}
+
+static ssize_t pn544_dev_read(struct file *filp, char __user *buf,
+                size_t count, loff_t *offset)
+{
+        struct pn544_dev *pn544_dev = filp->private_data;
+        char tmp[MAX_BUFFER_SIZE];
+        int ret;
+
+        if (count > MAX_BUFFER_SIZE)
+                count = MAX_BUFFER_SIZE;
+
+        pr_debug("%s : reading %zu bytes.\n", __func__, count);
+
+        mutex_lock(&pn544_dev->read_mutex);
+
+        if (!gpio_get_value(pn544_dev->irq_gpio)) {
+                if (filp->f_flags & O_NONBLOCK) {
+                        ret = -EAGAIN;
+                        goto fail;
+                }
+
+                pn544_dev->irq_enabled = true;
+                enable_irq(pn544_dev->client->irq);
+                ret = wait_event_interruptible(pn544_dev->read_wq,
+                                gpio_get_value(pn544_dev->irq_gpio));
+
+                pn544_disable_irq(pn544_dev);
+
+                if (ret)
+                        goto fail;
+
+        }
+
+        /* Read data */
+        ret = i2c_master_recv(pn544_dev->client, tmp, count);
+
+        mutex_unlock(&pn544_dev->read_mutex);
+
+        /* pn544 seems to be slow in handling I2C read requests
+         * so add 1ms delay after recv operation */
+        udelay(1000);
+
+        if (ret < 0) {
+                pr_err("%s: i2c_master_recv returned %d\n", __func__, ret);
+                return ret;
+        }
+        if (ret > count) {
+                pr_err("%s: received too many bytes from i2c (%d)\n",
+                        __func__, ret);
+                return -EIO;
+        }
+        if (copy_to_user(buf, tmp, ret)) {
+                pr_warning("%s : failed to copy to user space\n", __func__);
+                return -EFAULT;
+        }
+        return ret;
+
+fail:
+        mutex_unlock(&pn544_dev->read_mutex);
+        return ret;
+}
+
+static ssize_t pn544_dev_write(struct file *filp, const char __user *buf,
+                size_t count, loff_t *offset)
+{
+        struct pn544_dev  *pn544_dev;
+        char tmp[MAX_BUFFER_SIZE];
+        int ret;
+
+        pn544_dev = filp->private_data;
+
+        if (count > MAX_BUFFER_SIZE)
+                count = MAX_BUFFER_SIZE;
+
+        if (copy_from_user(tmp, buf, count)) {
+                pr_err("%s : failed to copy from user space\n", __func__);
+                return -EFAULT;
+        }
+
+        pr_debug("%s : writing %zu bytes.\n", __func__, count);
+        /* Write data */
+        ret = i2c_master_send(pn544_dev->client, tmp, count);
+        if (ret != count) {
+                pr_err("%s : i2c_master_send returned %d\n", __func__, ret);
+                ret = -EIO;
+        }
+
+        /* pn544 seems to be slow in handling I2C write requests
+         * so add 1ms delay after I2C send oparation */
+        udelay(1000);
+
+        return ret;
+}
+
+static int pn544_dev_open(struct inode *inode, struct file *filp)
+{
+        struct pn544_dev *pn544_dev = container_of(filp->private_data,
+                                                struct pn544_dev,
+                                                pn544_device);
+
+        filp->private_data = pn544_dev;
+
+        pr_debug("%s : %d,%d\n", __func__, imajor(inode), iminor(inode));
+
+        return 0;
+}
+
+static long  pn544_dev_ioctl(struct file *filp, unsigned int cmd,
+                                unsigned long arg)
+{
+        struct pn544_dev *pn544_dev = filp->private_data;
+
+        switch (cmd) {
+        case PN544_SET_PWR:
+                if (arg == 2) {
+                        /* power on with firmware download (requires hw reset)
+                         */
+                        pr_info("%s power on with firmware\n", __func__);
+                        gpio_set_value(pn544_dev->ven_gpio, 1);
+                        msleep(20);
+                        if (pn544_dev->firm_gpio)
+                                gpio_set_value(pn544_dev->firm_gpio, 1);
+                        msleep(20);
+                        gpio_set_value(pn544_dev->ven_gpio, 0);
+                        msleep(100);
+                        gpio_set_value(pn544_dev->ven_gpio, 1);
+                        msleep(20);
+                } else if (arg == 1) {
+                        /* power on */
+                        pr_info("%s power on\n", __func__);
+                        if (pn544_dev->firm_gpio)
+                                gpio_set_value(pn544_dev->firm_gpio, 0);
+                        gpio_set_value(pn544_dev->ven_gpio, 1);
+                        msleep(100);
+                } else  if (arg == 0) {
+                        /* power off */
+                        pr_info("%s power off\n", __func__);
+                        if (pn544_dev->firm_gpio)
+                                gpio_set_value(pn544_dev->firm_gpio, 0);
+                        gpio_set_value(pn544_dev->ven_gpio, 0);
+                        msleep(100);
+                } else {
+                        pr_err("%s bad arg %lu\n", __func__, arg);
+                        return -EINVAL;
+                }
+                break;
+        default:
+                pr_err("%s bad ioctl %u\n", __func__, cmd);
+                return -EINVAL;
+        }
+
+        return 0;
+}
+
+static const struct file_operations pn544_dev_fops = {
+        .owner  = THIS_MODULE,
+        .llseek = no_llseek,
+        .read   = pn544_dev_read,
+        .write  = pn544_dev_write,
+        .open   = pn544_dev_open,
+        .unlocked_ioctl  = pn544_dev_ioctl,
+};
+
+static int pn544_probe(struct i2c_client *client,
+                const struct i2c_device_id *id)
+{
+        int ret;
+        struct pn544_i2c_platform_data *platform_data;
+        struct pn544_dev *pn544_dev;
+
+        platform_data = client->dev.platform_data;
+
+        if (platform_data == NULL) {
+                pr_err("%s : nfc probe fail\n", __func__);
+                return  -ENODEV;
+        }
+
+        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+                pr_err("%s : need I2C_FUNC_I2C\n", __func__);
+                return  -ENODEV;
+        }
+
+        ret = gpio_request(platform_data->irq_gpio, "nfc_int");
+        if (ret)
+                return  -ENODEV;
+        ret = gpio_request(platform_data->ven_gpio, "nfc_ven");
+        if (ret)
+                goto err_ven;
+        if (platform_data->firm_gpio) {
+                ret = gpio_request(platform_data->firm_gpio, "nfc_firm");
+                if (ret)
+                        goto err_firm;
+        }
+
+        pn544_dev = kzalloc(sizeof(*pn544_dev), GFP_KERNEL);
+        if (pn544_dev == NULL) {
+                dev_err(&client->dev,
+                                "failed to allocate memory for module data\n");
+                ret = -ENOMEM;
+                goto err_exit;
+        }
+
+        pn544_dev->irq_gpio = platform_data->irq_gpio;
+        pn544_dev->ven_gpio  = platform_data->ven_gpio;
+        pn544_dev->firm_gpio  = platform_data->firm_gpio;
+        pn544_dev->client   = client;
+
+        ret = gpio_direction_input(pn544_dev->irq_gpio);
+        if (ret < 0) {
+                pr_err("%s :not able to set irq_gpio as input\n", __func__);
+                goto err_ven;
+        }
+        ret = gpio_direction_output(pn544_dev->ven_gpio, 0);
+        if (ret < 0) {
+                pr_err("%s : not able to set ven_gpio as output\n", __func__);
+                goto err_firm;
+        }
+        if (platform_data->firm_gpio) {
+                ret = gpio_direction_output(pn544_dev->firm_gpio, 0);
+                if (ret < 0) {
+                        pr_err("%s : not able to set firm_gpio as output\n",
+                                 __func__);
+                        goto err_exit;
+                }
+        }
+
+        /* init mutex and queues */
+        init_waitqueue_head(&pn544_dev->read_wq);
+        mutex_init(&pn544_dev->read_mutex);
+        spin_lock_init(&pn544_dev->irq_enabled_lock);
+
+        pn544_dev->pn544_device.minor = MISC_DYNAMIC_MINOR;
+        pn544_dev->pn544_device.name = "pn544";
+        pn544_dev->pn544_device.fops = &pn544_dev_fops;
+
+        ret = misc_register(&pn544_dev->pn544_device);
+        if (ret) {
+                pr_err("%s : misc_register failed\n", __FILE__);
+                goto err_misc_register;
+        }
+
+        /* request irq.  the irq is set whenever the chip has data available
+         * for reading.  it is cleared when all data has been read.
+         */
+        pr_info("%s : requesting IRQ %d\n", __func__, client->irq);
+        pn544_dev->irq_enabled = true;
+        ret = request_irq(client->irq, pn544_dev_irq_handler,
+                          IRQF_TRIGGER_HIGH, client->name, pn544_dev);
+        if (ret) {
+                dev_err(&client->dev, "request_irq failed\n");
+                goto err_request_irq_failed;
+        }
+        pn544_disable_irq(pn544_dev);
+        i2c_set_clientdata(client, pn544_dev);
+
+        return 0;
+
+err_request_irq_failed:
+        misc_deregister(&pn544_dev->pn544_device);
+err_misc_register:
+        mutex_destroy(&pn544_dev->read_mutex);
+        kfree(pn544_dev);
+err_exit:
+        if (pn544_dev->firm_gpio)
+                gpio_free(platform_data->firm_gpio);
+err_firm:
+        gpio_free(platform_data->ven_gpio);
+err_ven:
+        gpio_free(platform_data->irq_gpio);
+        return ret;
+}
+
+static int pn544_remove(struct i2c_client *client)
+{
+        struct pn544_dev *pn544_dev;
+
+        pn544_dev = i2c_get_clientdata(client);
+        free_irq(client->irq, pn544_dev);
+        misc_deregister(&pn544_dev->pn544_device);
+        mutex_destroy(&pn544_dev->read_mutex);
+        gpio_free(pn544_dev->irq_gpio);
+        gpio_free(pn544_dev->ven_gpio);
+        if (pn544_dev->firm_gpio)
+                gpio_free(pn544_dev->firm_gpio);
+        kfree(pn544_dev);
+
+        return 0;
+}
+
+static const struct i2c_device_id pn544_id[] = {
+        { "pn544", 0 },
+        { }
+};
+
+static struct i2c_driver pn544_driver = {
+        .id_table       = pn544_id,
+        .probe          = pn544_probe,
+        .remove         = pn544_remove,
+        .driver         = {
+                .owner  = THIS_MODULE,
+                .name   = "pn544",
+        },
+};
+
+/*
+ * module load/unload record keeping
+ */
+
+static int __init pn544_dev_init(void)
+{
+        pr_info("Loading pn544 driver\n");
+        return i2c_add_driver(&pn544_driver);
+}
+module_init(pn544_dev_init);
+
+static void __exit pn544_dev_exit(void)
+{
+        pr_info("Unloading pn544 driver\n");
+        i2c_del_driver(&pn544_driver);
+}
+module_exit(pn544_dev_exit);
+
+MODULE_AUTHOR("Sylvain Fonteneau");
+MODULE_DESCRIPTION("NFC PN544 driver");
+MODULE_LICENSE("GPL");