>From e213a725a0df02666a741751db5d5cdaebdfdfb5 Mon Sep 17 00:00:00 2001
From: Jeffrey Chu <jeff...@broadcom.com>
Date: Wed, 17 Apr 2013 13:13:33 -0400
Subject: [PATCH] i2c: Add bcm2079x-i2c client driver
bcm2079x-i2c support communicating with bcm2079x NFC Controller using i2c
transport.
Signed-off-by: Sheng-Hui Jeffrey Chu <jeff...@broadcom.com>
---
Documentation/nfc/nfc-bcm2079x-i2c.txt | 42 +++
drivers/nfc/Kconfig | 1 +
drivers/nfc/Makefile | 1 +
drivers/nfc/bcm2079x/Kconfig | 8 +
drivers/nfc/bcm2079x/Makefile | 4 +
drivers/nfc/bcm2079x/bcm2079x-i2c.c | 414 ++++++++++++++++++++++++++++++++
drivers/nfc/bcm2079x/bcm2079x.h | 34 +++
7 files changed, 504 insertions(+)
create mode 100644 Documentation/nfc/nfc-bcm2079x-i2c.txt
create mode 100644 drivers/nfc/bcm2079x/Kconfig
create mode 100644 drivers/nfc/bcm2079x/Makefile
create mode 100755 drivers/nfc/bcm2079x/bcm2079x-i2c.c
create mode 100644 drivers/nfc/bcm2079x/bcm2079x.h
diff --git a/Documentation/nfc/nfc-bcm2079x-i2c.txt
b/Documentation/nfc/nfc-bcm2079x-i2c.txt
new file mode 100644
index 0000000..ced1a0f
--- /dev/null
+++ b/Documentation/nfc/nfc-bcm2079x-i2c.txt
@@ -0,0 +1,42 @@
+Kernel driver for the Broadcom bcm2079x Near Field
+Communication controller
+
+General
+-------
+
+The bcm2079x is an integrated controller for contactless communication.
+
+Host Interfaces: I2C, SPI and UART, this driver supports I2C.
+
+The Driver
+----------
+
+The bcm2079x-i2c driver can be found under drivers/nfc/bcm2079x/bcm2079x-i2c.c
and
+its header file drivers/nfc/bcm2079x/bcm2079x.h.
+
+The userspace application uses /dev/bcm2079x-i2c device to communicate with the
+NFC Controller using NCI command messages. In a typical scenario application
will
+open /dev/bcm2079x-i2c; power up and wake up the controller chip using ioctl().
+write to the controller using write(). poll() the device to check if data is
+available. Use read() to read the data from the controller.
+
+The driver waits for bcm2079x controller interrupt which occurs if there are
some
+data to be read. Then, poll() will indicate that fact to the userspace.
+
+Userspace application may use ioctl() to allow the Controller to enter snooze
or
+sleep mode.
+
+Userspace application may use ioctl() to set the client address the driver use
to
+communicate with the Controller. This allows userspace application to change
the
+device address of the Controller.
+
+Platform Data
+-------------
+
+The following platform data should be set when configuring board.
+
+struct bcm2079x_platform_data {
+ unsigned int irq_gpio;
+ unsigned int en_gpio;
+ unsigned int wake_gpio;
+};
diff --git a/drivers/nfc/Kconfig b/drivers/nfc/Kconfig
index e570349..f9bf203 100644
--- a/drivers/nfc/Kconfig
+++ b/drivers/nfc/Kconfig
@@ -28,5 +28,6 @@ config NFC_WILINK
source "drivers/nfc/pn544/Kconfig"
source "drivers/nfc/microread/Kconfig"
+source "drivers/nfc/bcm2079x/Kconfig"
endmenu
diff --git a/drivers/nfc/Makefile b/drivers/nfc/Makefile
index a189ada0..ee48e07 100644
--- a/drivers/nfc/Makefile
+++ b/drivers/nfc/Makefile
@@ -6,5 +6,6 @@ obj-$(CONFIG_NFC_PN544) += pn544/
obj-$(CONFIG_NFC_MICROREAD) += microread/
obj-$(CONFIG_NFC_PN533) += pn533.o
obj-$(CONFIG_NFC_WILINK) += nfcwilink.o
+obj-$(CONFIG_NFC_BCM2079X_I2C) += bcm2079x/
ccflags-$(CONFIG_NFC_DEBUG) := -DDEBUG
diff --git a/drivers/nfc/bcm2079x/Kconfig b/drivers/nfc/bcm2079x/Kconfig
new file mode 100644
index 0000000..eed3138
--- /dev/null
+++ b/drivers/nfc/bcm2079x/Kconfig
@@ -0,0 +1,8 @@
+config NFC_BCM2079X_I2C
+ tristate "NFC BCM2079x i2c support"
+ depends on I2C
+ ---help---
+ This module adds support for the i2c interface of NFC Controller using
+ Broadcom bcm2079x chip. Select this if your platform is using
+ the i2c bus.
+ default n
diff --git a/drivers/nfc/bcm2079x/Makefile b/drivers/nfc/bcm2079x/Makefile
new file mode 100644
index 0000000..be64d35
--- /dev/null
+++ b/drivers/nfc/bcm2079x/Makefile
@@ -0,0 +1,4 @@
+#
+# Makefile for bcm2079x NFC driver
+#
+obj-$(CONFIG_NFC_BCM2079X_I2C) += bcm2079x-i2c.o
diff --git a/drivers/nfc/bcm2079x/bcm2079x-i2c.c
b/drivers/nfc/bcm2079x/bcm2079x-i2c.c
new file mode 100755
index 0000000..e632380
--- /dev/null
+++ b/drivers/nfc/bcm2079x/bcm2079x-i2c.c
@@ -0,0 +1,414 @@
+/*
+ * Copyright (C) 2012 Broadcom Corporation.
+ *
+ * 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/module.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/gpio.h>
+#include <linux/miscdevice.h>
+#include <linux/spinlock.h>
+#include <linux/poll.h>
+
+#include "bcm2079x.h"
+
+/* do not change below */
+#define MAX_BUFFER_SIZE 780
+
+/* Read data */
+#define PACKET_HEADER_SIZE_NCI (4)
+#define PACKET_HEADER_SIZE_HCI (3)
+#define PACKET_TYPE_NCI (16)
+#define PACKET_TYPE_HCIEV (4)
+#define MAX_PACKET_SIZE (PACKET_HEADER_SIZE_NCI + 255)
+
+struct bcm2079x_dev {
+ wait_queue_head_t read_wq;
+ struct mutex read_mutex;
+ struct i2c_client *client;
+ struct miscdevice bcm2079x_device;
+ unsigned int wake_gpio;
+ unsigned int en_gpio;
+ unsigned int irq_gpio;
+ bool irq_enabled;
+ spinlock_t irq_enabled_lock;
+ unsigned int count_irq;
+};
+
+static void bcm2079x_init_stat(struct bcm2079x_dev *bcm2079x_dev)
+{
+ bcm2079x_dev->count_irq = 0;
+}
+
+static void bcm2079x_disable_irq(struct bcm2079x_dev *bcm2079x_dev)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&bcm2079x_dev->irq_enabled_lock, flags);
+ if (bcm2079x_dev->irq_enabled) {
+ disable_irq_nosync(bcm2079x_dev->client->irq);
+ bcm2079x_dev->irq_enabled = false;
+ }
+ spin_unlock_irqrestore(&bcm2079x_dev->irq_enabled_lock, flags);
+}
+
+static void bcm2079x_enable_irq(struct bcm2079x_dev *bcm2079x_dev)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&bcm2079x_dev->irq_enabled_lock, flags);
+ if (!bcm2079x_dev->irq_enabled) {
+ bcm2079x_dev->irq_enabled = true;
+ enable_irq(bcm2079x_dev->client->irq);
+ }
+ spin_unlock_irqrestore(&bcm2079x_dev->irq_enabled_lock, flags);
+}
+
+static void set_client_addr(struct bcm2079x_dev *bcm2079x_dev, int addr)
+{
+ struct i2c_client *client = bcm2079x_dev->client;
+ dev_info(&client->dev,
+ "Set client device address from 0x%04X flag = "\
+ "%02x, to 0x%04X\n",
+ client->addr, client->flags, addr);
+ client->addr = addr;
+ if (addr < 0x80)
+ client->flags &= ~I2C_CLIENT_TEN;
+ else
+ client->flags |= I2C_CLIENT_TEN;
+}
+
+static irqreturn_t bcm2079x_dev_irq_handler(int irq, void *dev_id)
+{
+ struct bcm2079x_dev *bcm2079x_dev = dev_id;
+ unsigned long flags;
+
+ spin_lock_irqsave(&bcm2079x_dev->irq_enabled_lock, flags);
+ bcm2079x_dev->count_irq++;
+ spin_unlock_irqrestore(&bcm2079x_dev->irq_enabled_lock, flags);
+ wake_up(&bcm2079x_dev->read_wq);
+
+ return IRQ_HANDLED;
+}
+
+static unsigned int bcm2079x_dev_poll(struct file *filp, poll_table *wait)
+{
+ struct bcm2079x_dev *bcm2079x_dev = filp->private_data;
+ unsigned int mask = 0;
+ unsigned long flags;
+
+ poll_wait(filp, &bcm2079x_dev->read_wq, wait);
+
+ spin_lock_irqsave(&bcm2079x_dev->irq_enabled_lock, flags);
+ if (bcm2079x_dev->count_irq > 0) {
+ bcm2079x_dev->count_irq--;
+ mask |= POLLIN | POLLRDNORM;
+ }
+ spin_unlock_irqrestore(&bcm2079x_dev->irq_enabled_lock, flags);
+
+ return mask;
+}
+
+static ssize_t bcm2079x_dev_read(struct file *filp, char __user *buf,
+ size_t count, loff_t *offset)
+{
+ struct bcm2079x_dev *bcm2079x_dev = filp->private_data;
+ unsigned char tmp[MAX_BUFFER_SIZE];
+ int total, len, ret;
+
+ total = 0;
+ len = 0;
+
+ if (count > MAX_BUFFER_SIZE)
+ count = MAX_BUFFER_SIZE;
+
+ mutex_lock(&bcm2079x_dev->read_mutex);
+
+ /** Read the first 4 bytes to include the length of the NCI or HCI
packet.
+ **/
+ ret = i2c_master_recv(bcm2079x_dev->client, tmp, 4);
+ if (ret == 4) {
+ total = ret;
+ /** First byte is the packet type
+ **/
+ switch(tmp[0]) {
+ case PACKET_TYPE_NCI:
+ len = tmp[PACKET_HEADER_SIZE_NCI-1];
+ break;
+
+ case PACKET_TYPE_HCIEV:
+ len = tmp[PACKET_HEADER_SIZE_HCI-1];
+ if (len == 0)
+ total--;/*Since payload is 0, decrement
total size (from 4 to 3) */
+ else
+ len--;/*First byte of payload is in
tmp[3] already */
+ break;
+
+ default:
+ len = 0;/*Unknown packet byte */
+ break;
+ } /* switch*/
+
+ /** make sure full packet fits in the buffer
+ **/
+ if (len > 0 && (len + total) <= count) {
+ /** read the remainder of the packet.
+ **/
+ ret = i2c_master_recv(bcm2079x_dev->client, tmp+total,
len);
+ if (ret == len)
+ total += len;
+ } /* if */
+ } /* if */
+
+ mutex_unlock(&bcm2079x_dev->read_mutex);
+
+ if (total > count || copy_to_user(buf, tmp, total)) {
+ dev_err(&bcm2079x_dev->client->dev,
+ "failed to copy to user space, total = %d\n", total);
+ total = -EFAULT;
+ }
+
+ return total;
+}
+
+static ssize_t bcm2079x_dev_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *offset)
+{
+ struct bcm2079x_dev *bcm2079x_dev = filp->private_data;
+ char tmp[MAX_BUFFER_SIZE];
+ int ret;
+
+ if (count > MAX_BUFFER_SIZE) {
+ dev_err(&bcm2079x_dev->client->dev, "out of memory\n");
+ return -ENOMEM;
+ }
+
+ if (copy_from_user(tmp, buf, count)) {
+ dev_err(&bcm2079x_dev->client->dev,
+ "failed to copy from user space\n");
+ return -EFAULT;
+ }
+
+ mutex_lock(&bcm2079x_dev->read_mutex);
+ /* Write data */
+
+ ret = i2c_master_send(bcm2079x_dev->client, tmp, count);
+ if (ret != count) {
+ dev_err(&bcm2079x_dev->client->dev,
+ "failed to write %d\n", ret);
+ ret = -EIO;
+ }
+ mutex_unlock(&bcm2079x_dev->read_mutex);
+
+ return ret;
+}
+
+static int bcm2079x_dev_open(struct inode *inode, struct file *filp)
+{
+ int ret = 0;
+
+ struct bcm2079x_dev *bcm2079x_dev = container_of(filp->private_data,
+ struct bcm2079x_dev,
+ bcm2079x_device);
+ filp->private_data = bcm2079x_dev;
+ bcm2079x_init_stat(bcm2079x_dev);
+ bcm2079x_enable_irq(bcm2079x_dev);
+ dev_info(&bcm2079x_dev->client->dev,
+ "%d,%d\n", imajor(inode), iminor(inode));
+
+ return ret;
+}
+
+static long bcm2079x_dev_unlocked_ioctl(struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ struct bcm2079x_dev *bcm2079x_dev = filp->private_data;
+
+ switch (cmd) {
+ case BCMNFC_POWER_CTL:
+ gpio_set_value(bcm2079x_dev->en_gpio, arg);
+ break;
+ case BCMNFC_WAKE_CTL:
+ gpio_set_value(bcm2079x_dev->wake_gpio, arg);
+ break;
+ case BCMNFC_SET_ADDR:
+ set_client_addr(bcm2079x_dev, arg);
+ break;
+ default:
+ dev_err(&bcm2079x_dev->client->dev,
+ "%s, unknown cmd (%x, %lx)\n", __func__, cmd, arg);
+ return -ENOSYS;
+ }
+
+ return 0;
+}
+
+static const struct file_operations bcm2079x_dev_fops = {
+ .owner = THIS_MODULE,
+ .llseek = no_llseek,
+ .poll = bcm2079x_dev_poll,
+ .read = bcm2079x_dev_read,
+ .write = bcm2079x_dev_write,
+ .open = bcm2079x_dev_open,
+ .unlocked_ioctl = bcm2079x_dev_unlocked_ioctl
+};
+
+static int bcm2079x_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct bcm2079x_platform_data *platform_data;
+ struct bcm2079x_dev *bcm2079x_dev;
+
+ platform_data = client->dev.platform_data;
+
+ dev_info(&client->dev, "%s, probing bcm2079x driver flags = %x\n",
__func__, client->flags);
+ if (platform_data == NULL) {
+ dev_err(&client->dev, "nfc probe fail\n");
+ return -ENODEV;
+ }
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ dev_err(&client->dev, "need I2C_FUNC_I2C\n");
+ return -ENODEV;
+ }
+
+ ret = gpio_request_one(platform_data->irq_gpio, GPIOF_IN, "nfc_irq");
+ if (ret)
+ return -ENODEV;
+ ret = gpio_request_one(platform_data->en_gpio, GPIOF_OUT_INIT_LOW,
"nfc_en");
+ if (ret)
+ goto err_en;
+ ret = gpio_request_one(platform_data->wake_gpio,
GPIOF_OUT_INIT_LOW,"nfc_wake");
+ if (ret)
+ goto err_wake;
+
+ gpio_set_value(platform_data->en_gpio, 0);
+ gpio_set_value(platform_data->wake_gpio, 0);
+
+ bcm2079x_dev = kzalloc(sizeof(*bcm2079x_dev), GFP_KERNEL);
+ if (bcm2079x_dev == NULL) {
+ dev_err(&client->dev,
+ "failed to allocate memory for module data\n");
+ ret = -ENOMEM;
+ goto err_exit;
+ }
+
+ bcm2079x_dev->wake_gpio = platform_data->wake_gpio;
+ bcm2079x_dev->irq_gpio = platform_data->irq_gpio;
+ bcm2079x_dev->en_gpio = platform_data->en_gpio;
+ bcm2079x_dev->client = client;
+
+ /* init mutex and queues */
+ init_waitqueue_head(&bcm2079x_dev->read_wq);
+ mutex_init(&bcm2079x_dev->read_mutex);
+ spin_lock_init(&bcm2079x_dev->irq_enabled_lock);
+
+ bcm2079x_dev->bcm2079x_device.minor = MISC_DYNAMIC_MINOR;
+ bcm2079x_dev->bcm2079x_device.name = "bcm2079x-i2c";
+ bcm2079x_dev->bcm2079x_device.fops = &bcm2079x_dev_fops;
+
+ ret = misc_register(&bcm2079x_dev->bcm2079x_device);
+ if (ret) {
+ dev_err(&client->dev, "misc_register failed\n");
+ 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.
+ */
+ dev_info(&client->dev, "requesting IRQ %d\n", client->irq);
+ bcm2079x_dev->irq_enabled = true;
+ ret = request_irq(client->irq, bcm2079x_dev_irq_handler,
+ IRQF_TRIGGER_RISING, client->name, bcm2079x_dev);
+ if (ret) {
+ dev_err(&client->dev, "request_irq failed\n");
+ goto err_request_irq_failed;
+ }
+ bcm2079x_disable_irq(bcm2079x_dev);
+ i2c_set_clientdata(client, bcm2079x_dev);
+ dev_info(&client->dev,
+ "%s, probing bcm2079x driver exited successfully\n",
+ __func__);
+ return 0;
+
+err_request_irq_failed:
+ misc_deregister(&bcm2079x_dev->bcm2079x_device);
+err_misc_register:
+ mutex_destroy(&bcm2079x_dev->read_mutex);
+ kfree(bcm2079x_dev);
+err_exit:
+ gpio_free(platform_data->wake_gpio);
+err_wake:
+ gpio_free(platform_data->en_gpio);
+err_en:
+ gpio_free(platform_data->irq_gpio);
+ return ret;
+}
+
+static int bcm2079x_remove(struct i2c_client *client)
+{
+ struct bcm2079x_dev *bcm2079x_dev;
+
+ bcm2079x_dev = i2c_get_clientdata(client);
+ free_irq(client->irq, bcm2079x_dev);
+ misc_deregister(&bcm2079x_dev->bcm2079x_device);
+ mutex_destroy(&bcm2079x_dev->read_mutex);
+ gpio_free(bcm2079x_dev->irq_gpio);
+ gpio_free(bcm2079x_dev->en_gpio);
+ gpio_free(bcm2079x_dev->wake_gpio);
+ kfree(bcm2079x_dev);
+
+ return 0;
+}
+
+static const struct i2c_device_id bcm2079x_id[] = {
+ {"bcm2079x-i2c", 0},
+ {}
+};
+
+static struct i2c_driver bcm2079x_driver = {
+ .id_table = bcm2079x_id,
+ .probe = bcm2079x_probe,
+ .remove = bcm2079x_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "bcm2079x-i2c",
+ },
+};
+
+/*
+ * module load/unload record keeping
+ */
+
+static int __init bcm2079x_dev_init(void)
+{
+ return i2c_add_driver(&bcm2079x_driver);
+}
+module_init(bcm2079x_dev_init);
+
+static void __exit bcm2079x_dev_exit(void)
+{
+ i2c_del_driver(&bcm2079x_driver);
+}
+module_exit(bcm2079x_dev_exit);
+
+MODULE_AUTHOR("Broadcom");
+MODULE_DESCRIPTION("NFC bcm2079x driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/nfc/bcm2079x/bcm2079x.h b/drivers/nfc/bcm2079x/bcm2079x.h
new file mode 100644
index 0000000..4f1bf7f
--- /dev/null
+++ b/drivers/nfc/bcm2079x/bcm2079x.h
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2012 Broadcom Corporation.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _BCM2079X_H
+#define _BCM2079X_H
+
+#define BCMNFC_MAGIC 0xFA
+
+#define BCMNFC_POWER_CTL _IO(BCMNFC_MAGIC, 0x01)
+#define BCMNFC_WAKE_CTL _IO(BCMNFC_MAGIC, 0x05)
+#define BCMNFC_SET_ADDR _IO(BCMNFC_MAGIC, 0x07)
+
+struct bcm2079x_platform_data {
+ unsigned int irq_gpio;
+ unsigned int en_gpio;
+ unsigned int wake_gpio;
+};
+
+#endif
--
1.7.10.4
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