diff options
Diffstat (limited to 'bcm2079x-i2c.c')
-rw-r--r-- | bcm2079x-i2c.c | 420 |
1 files changed, 420 insertions, 0 deletions
diff --git a/bcm2079x-i2c.c b/bcm2079x-i2c.c new file mode 100644 index 000000000000..78ba6c9e0a92 --- /dev/null +++ b/bcm2079x-i2c.c @@ -0,0 +1,420 @@ +/* + * 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 <linux/platform_data/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 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 payload is 0, decrement total size (from 4 to 3) */ + if (len == 0) + total--; + /*Otherwise, discount payload length byte*/ + else + len--; + 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 BCMXXC_POWER_CTL: + gpio_set_value(bcm2079x_dev->en_gpio, arg); + break; + case BCMXXC_WAKE_CTL: + gpio_set_value(bcm2079x_dev->wake_gpio, arg); + break; + case BCMXXC_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, "device 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, "xxc_irq"); + if (ret) + return -ENODEV; + ret = gpio_request_one(platform_data->en_gpio, + GPIOF_OUT_INIT_LOW, "xxc_en"); + if (ret) + goto err_en; + ret = gpio_request_one(platform_data->wake_gpio, + GPIOF_OUT_INIT_LOW, "xxc_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("bcm2079x contrller driver"); +MODULE_LICENSE("GPL"); |