From patchwork Wed May 1 16:38:07 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Jeffrey (Sheng-Hui) Chu" X-Patchwork-Id: 240788 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 482AD2C009D for ; Thu, 2 May 2013 02:38:21 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756684Ab3EAQiU (ORCPT ); Wed, 1 May 2013 12:38:20 -0400 Received: from mms1.broadcom.com ([216.31.210.17]:2841 "EHLO mms1.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756165Ab3EAQiT convert rfc822-to-8bit (ORCPT ); Wed, 1 May 2013 12:38:19 -0400 Received: from [10.9.208.26] by mms1.broadcom.com with ESMTP (Broadcom SMTP Relay (Email Firewall v6.5)); Wed, 01 May 2013 09:34:37 -0700 X-Server-Uuid: 06151B78-6688-425E-9DE2-57CB27892261 Received: from IRVEXCHMB07.corp.ad.broadcom.com ( [fe80::210e:9528:8c52:eb93]) by IRVEXCHCAS05.corp.ad.broadcom.com ( [::1]) with mapi id 14.01.0438.000; Wed, 1 May 2013 09:38:07 -0700 From: "Jeffrey (Sheng-Hui) Chu" To: "linux-i2c@vger.kernel.org" Subject: [PATCH] i2c: Add bcm2079x-i2c client driver Thread-Topic: [PATCH] i2c: Add bcm2079x-i2c client driver Thread-Index: Ac5Gf/RfcdQlaiX2Tk+vN7O/pRyUIA== Date: Wed, 1 May 2013 16:38:07 +0000 Message-ID: <90AC93A0CCA054488FFC508D6F62B6F40FE26890@IRVEXCHMB07.corp.ad.broadcom.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.9.208.64] MIME-Version: 1.0 X-WSS-ID: 7D9F9B9731W13720004-01-01 Sender: linux-i2c-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org From e213a725a0df02666a741751db5d5cdaebdfdfb5 Mon Sep 17 00:00:00 2001 From: Jeffrey Chu 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 --- 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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