diff options
Diffstat (limited to 'drivers/hsi/clients/hsi_char.c')
| -rw-r--r-- | drivers/hsi/clients/hsi_char.c | 802 |
1 files changed, 802 insertions, 0 deletions
diff --git a/drivers/hsi/clients/hsi_char.c b/drivers/hsi/clients/hsi_char.c new file mode 100644 index 000000000000..88a050df2389 --- /dev/null +++ b/drivers/hsi/clients/hsi_char.c @@ -0,0 +1,802 @@ +/* + * HSI character device driver, implements the character device + * interface. + * + * Copyright (C) 2010 Nokia Corporation. All rights reserved. + * + * Contact: Andras Domokos <andras.domokos@nokia.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms 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, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/atomic.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/kmemleak.h> +#include <linux/ioctl.h> +#include <linux/wait.h> +#include <linux/fs.h> +#include <linux/sched.h> +#include <linux/device.h> +#include <linux/cdev.h> +#include <linux/uaccess.h> +#include <linux/scatterlist.h> +#include <linux/stat.h> +#include <linux/hsi/hsi.h> +#include <linux/hsi/hsi_char.h> + +#define HSC_DEVS 16 /* Num of channels */ +#define HSC_MSGS 4 + +#define HSC_RXBREAK 0 + +#define HSC_ID_BITS 6 +#define HSC_PORT_ID_BITS 4 +#define HSC_ID_MASK 3 +#define HSC_PORT_ID_MASK 3 +#define HSC_CH_MASK 0xf + +/* + * We support up to 4 controllers that can have up to 4 + * ports, which should currently be more than enough. + */ +#define HSC_BASEMINOR(id, port_id) \ + ((((id) & HSC_ID_MASK) << HSC_ID_BITS) | \ + (((port_id) & HSC_PORT_ID_MASK) << HSC_PORT_ID_BITS)) + +enum { + HSC_CH_OPEN, + HSC_CH_READ, + HSC_CH_WRITE, + HSC_CH_WLINE, +}; + +enum { + HSC_RX, + HSC_TX, +}; + +struct hsc_client_data; +/** + * struct hsc_channel - hsi_char internal channel data + * @ch: channel number + * @flags: Keeps state of the channel (open/close, reading, writing) + * @free_msgs_list: List of free HSI messages/requests + * @rx_msgs_queue: List of pending RX requests + * @tx_msgs_queue: List of pending TX requests + * @lock: Serialize access to the lists + * @cl: reference to the associated hsi_client + * @cl_data: reference to the client data that this channels belongs to + * @rx_wait: RX requests wait queue + * @tx_wait: TX requests wait queue + */ +struct hsc_channel { + unsigned int ch; + unsigned long flags; + struct list_head free_msgs_list; + struct list_head rx_msgs_queue; + struct list_head tx_msgs_queue; + spinlock_t lock; + struct hsi_client *cl; + struct hsc_client_data *cl_data; + wait_queue_head_t rx_wait; + wait_queue_head_t tx_wait; +}; + +/** + * struct hsc_client_data - hsi_char internal client data + * @cdev: Characther device associated to the hsi_client + * @lock: Lock to serialize open/close access + * @flags: Keeps track of port state (rx hwbreak armed) + * @usecnt: Use count for claiming the HSI port (mutex protected) + * @cl: Referece to the HSI client + * @channels: Array of channels accessible by the client + */ +struct hsc_client_data { + struct cdev cdev; + struct mutex lock; + unsigned long flags; + unsigned int usecnt; + struct hsi_client *cl; + struct hsc_channel channels[HSC_DEVS]; +}; + +/* Stores the major number dynamically allocated for hsi_char */ +static unsigned int hsc_major; +/* Maximum buffer size that hsi_char will accept from userspace */ +static unsigned int max_data_size = 0x1000; +module_param(max_data_size, uint, S_IRUSR | S_IWUSR); +MODULE_PARM_DESC(max_data_size, "max read/write data size [4,8..65536] (^2)"); + +static void hsc_add_tail(struct hsc_channel *channel, struct hsi_msg *msg, + struct list_head *queue) +{ + unsigned long flags; + + spin_lock_irqsave(&channel->lock, flags); + list_add_tail(&msg->link, queue); + spin_unlock_irqrestore(&channel->lock, flags); +} + +static struct hsi_msg *hsc_get_first_msg(struct hsc_channel *channel, + struct list_head *queue) +{ + struct hsi_msg *msg = NULL; + unsigned long flags; + + spin_lock_irqsave(&channel->lock, flags); + + if (list_empty(queue)) + goto out; + + msg = list_first_entry(queue, struct hsi_msg, link); + list_del(&msg->link); +out: + spin_unlock_irqrestore(&channel->lock, flags); + + return msg; +} + +static inline void hsc_msg_free(struct hsi_msg *msg) +{ + kfree(sg_virt(msg->sgt.sgl)); + hsi_free_msg(msg); +} + +static void hsc_free_list(struct list_head *list) +{ + struct hsi_msg *msg, *tmp; + + list_for_each_entry_safe(msg, tmp, list, link) { + list_del(&msg->link); + hsc_msg_free(msg); + } +} + +static void hsc_reset_list(struct hsc_channel *channel, struct list_head *l) +{ + unsigned long flags; + LIST_HEAD(list); + + spin_lock_irqsave(&channel->lock, flags); + list_splice_init(l, &list); + spin_unlock_irqrestore(&channel->lock, flags); + + hsc_free_list(&list); +} + +static inline struct hsi_msg *hsc_msg_alloc(unsigned int alloc_size) +{ + struct hsi_msg *msg; + void *buf; + + msg = hsi_alloc_msg(1, GFP_KERNEL); + if (!msg) + goto out; + buf = kmalloc(alloc_size, GFP_KERNEL); + if (!buf) { + hsi_free_msg(msg); + goto out; + } + sg_init_one(msg->sgt.sgl, buf, alloc_size); + /* Ignore false positive, due to sg pointer handling */ + kmemleak_ignore(buf); + + return msg; +out: + return NULL; +} + +static inline int hsc_msgs_alloc(struct hsc_channel *channel) +{ + struct hsi_msg *msg; + int i; + + for (i = 0; i < HSC_MSGS; i++) { + msg = hsc_msg_alloc(max_data_size); + if (!msg) + goto out; + msg->channel = channel->ch; + list_add_tail(&msg->link, &channel->free_msgs_list); + } + + return 0; +out: + hsc_free_list(&channel->free_msgs_list); + + return -ENOMEM; +} + +static inline unsigned int hsc_msg_len_get(struct hsi_msg *msg) +{ + return msg->sgt.sgl->length; +} + +static inline void hsc_msg_len_set(struct hsi_msg *msg, unsigned int len) +{ + msg->sgt.sgl->length = len; +} + +static void hsc_rx_completed(struct hsi_msg *msg) +{ + struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl); + struct hsc_channel *channel = cl_data->channels + msg->channel; + + if (test_bit(HSC_CH_READ, &channel->flags)) { + hsc_add_tail(channel, msg, &channel->rx_msgs_queue); + wake_up(&channel->rx_wait); + } else { + hsc_add_tail(channel, msg, &channel->free_msgs_list); + } +} + +static void hsc_rx_msg_destructor(struct hsi_msg *msg) +{ + msg->status = HSI_STATUS_ERROR; + hsc_msg_len_set(msg, 0); + hsc_rx_completed(msg); +} + +static void hsc_tx_completed(struct hsi_msg *msg) +{ + struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl); + struct hsc_channel *channel = cl_data->channels + msg->channel; + + if (test_bit(HSC_CH_WRITE, &channel->flags)) { + hsc_add_tail(channel, msg, &channel->tx_msgs_queue); + wake_up(&channel->tx_wait); + } else { + hsc_add_tail(channel, msg, &channel->free_msgs_list); + } +} + +static void hsc_tx_msg_destructor(struct hsi_msg *msg) +{ + msg->status = HSI_STATUS_ERROR; + hsc_msg_len_set(msg, 0); + hsc_tx_completed(msg); +} + +static void hsc_break_req_destructor(struct hsi_msg *msg) +{ + struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl); + + hsi_free_msg(msg); + clear_bit(HSC_RXBREAK, &cl_data->flags); +} + +static void hsc_break_received(struct hsi_msg *msg) +{ + struct hsc_client_data *cl_data = hsi_client_drvdata(msg->cl); + struct hsc_channel *channel = cl_data->channels; + int i, ret; + + /* Broadcast HWBREAK on all channels */ + for (i = 0; i < HSC_DEVS; i++, channel++) { + struct hsi_msg *msg2; + + if (!test_bit(HSC_CH_READ, &channel->flags)) + continue; + msg2 = hsc_get_first_msg(channel, &channel->free_msgs_list); + if (!msg2) + continue; + clear_bit(HSC_CH_READ, &channel->flags); + hsc_msg_len_set(msg2, 0); + msg2->status = HSI_STATUS_COMPLETED; + hsc_add_tail(channel, msg2, &channel->rx_msgs_queue); + wake_up(&channel->rx_wait); + } + hsi_flush(msg->cl); + ret = hsi_async_read(msg->cl, msg); + if (ret < 0) + hsc_break_req_destructor(msg); +} + +static int hsc_break_request(struct hsi_client *cl) +{ + struct hsc_client_data *cl_data = hsi_client_drvdata(cl); + struct hsi_msg *msg; + int ret; + + if (test_and_set_bit(HSC_RXBREAK, &cl_data->flags)) + return -EBUSY; + + msg = hsi_alloc_msg(0, GFP_KERNEL); + if (!msg) { + clear_bit(HSC_RXBREAK, &cl_data->flags); + return -ENOMEM; + } + msg->break_frame = 1; + msg->complete = hsc_break_received; + msg->destructor = hsc_break_req_destructor; + ret = hsi_async_read(cl, msg); + if (ret < 0) + hsc_break_req_destructor(msg); + + return ret; +} + +static int hsc_break_send(struct hsi_client *cl) +{ + struct hsi_msg *msg; + int ret; + + msg = hsi_alloc_msg(0, GFP_ATOMIC); + if (!msg) + return -ENOMEM; + msg->break_frame = 1; + msg->complete = hsi_free_msg; + msg->destructor = hsi_free_msg; + ret = hsi_async_write(cl, msg); + if (ret < 0) + hsi_free_msg(msg); + + return ret; +} + +static int hsc_rx_set(struct hsi_client *cl, struct hsc_rx_config *rxc) +{ + struct hsi_config tmp; + int ret; + + if ((rxc->mode != HSI_MODE_STREAM) && (rxc->mode != HSI_MODE_FRAME)) + return -EINVAL; + if ((rxc->channels == 0) || (rxc->channels > HSC_DEVS)) + return -EINVAL; + if (rxc->channels & (rxc->channels - 1)) + return -EINVAL; + if ((rxc->flow != HSI_FLOW_SYNC) && (rxc->flow != HSI_FLOW_PIPE)) + return -EINVAL; + tmp = cl->rx_cfg; + cl->rx_cfg.mode = rxc->mode; + cl->rx_cfg.channels = rxc->channels; + cl->rx_cfg.flow = rxc->flow; + ret = hsi_setup(cl); + if (ret < 0) { + cl->rx_cfg = tmp; + return ret; + } + if (rxc->mode == HSI_MODE_FRAME) + hsc_break_request(cl); + + return ret; +} + +static inline void hsc_rx_get(struct hsi_client *cl, struct hsc_rx_config *rxc) +{ + rxc->mode = cl->rx_cfg.mode; + rxc->channels = cl->rx_cfg.channels; + rxc->flow = cl->rx_cfg.flow; +} + +static int hsc_tx_set(struct hsi_client *cl, struct hsc_tx_config *txc) +{ + struct hsi_config tmp; + int ret; + + if ((txc->mode != HSI_MODE_STREAM) && (txc->mode != HSI_MODE_FRAME)) + return -EINVAL; + if ((txc->channels == 0) || (txc->channels > HSC_DEVS)) + return -EINVAL; + if (txc->channels & (txc->channels - 1)) + return -EINVAL; + if ((txc->arb_mode != HSI_ARB_RR) && (txc->arb_mode != HSI_ARB_PRIO)) + return -EINVAL; + tmp = cl->tx_cfg; + cl->tx_cfg.mode = txc->mode; + cl->tx_cfg.channels = txc->channels; + cl->tx_cfg.speed = txc->speed; + cl->tx_cfg.arb_mode = txc->arb_mode; + ret = hsi_setup(cl); + if (ret < 0) { + cl->tx_cfg = tmp; + return ret; + } + + return ret; +} + +static inline void hsc_tx_get(struct hsi_client *cl, struct hsc_tx_config *txc) +{ + txc->mode = cl->tx_cfg.mode; + txc->channels = cl->tx_cfg.channels; + txc->speed = cl->tx_cfg.speed; + txc->arb_mode = cl->tx_cfg.arb_mode; +} + +static ssize_t hsc_read(struct file *file, char __user *buf, size_t len, + loff_t *ppos __maybe_unused) +{ + struct hsc_channel *channel = file->private_data; + struct hsi_msg *msg; + ssize_t ret; + + if (len == 0) + return 0; + if (!IS_ALIGNED(len, sizeof(u32))) + return -EINVAL; + if (len > max_data_size) + len = max_data_size; + if (channel->ch >= channel->cl->rx_cfg.channels) + return -ECHRNG; + if (test_and_set_bit(HSC_CH_READ, &channel->flags)) + return -EBUSY; + msg = hsc_get_first_msg(channel, &channel->free_msgs_list); + if (!msg) { + ret = -ENOSPC; + goto out; + } + hsc_msg_len_set(msg, len); + msg->complete = hsc_rx_completed; + msg->destructor = hsc_rx_msg_destructor; + ret = hsi_async_read(channel->cl, msg); + if (ret < 0) { + hsc_add_tail(channel, msg, &channel->free_msgs_list); + goto out; + } + + ret = wait_event_interruptible(channel->rx_wait, + !list_empty(&channel->rx_msgs_queue)); + if (ret < 0) { + clear_bit(HSC_CH_READ, &channel->flags); + hsi_flush(channel->cl); + return -EINTR; + } + + msg = hsc_get_first_msg(channel, &channel->rx_msgs_queue); + if (msg) { + if (msg->status != HSI_STATUS_ERROR) { + ret = copy_to_user((void __user *)buf, + sg_virt(msg->sgt.sgl), hsc_msg_len_get(msg)); + if (ret) + ret = -EFAULT; + else + ret = hsc_msg_len_get(msg); + } else { + ret = -EIO; + } + hsc_add_tail(channel, msg, &channel->free_msgs_list); + } +out: + clear_bit(HSC_CH_READ, &channel->flags); + + return ret; +} + +static ssize_t hsc_write(struct file *file, const char __user *buf, size_t len, + loff_t *ppos __maybe_unused) +{ + struct hsc_channel *channel = file->private_data; + struct hsi_msg *msg; + ssize_t ret; + + if ((len == 0) || !IS_ALIGNED(len, sizeof(u32))) + return -EINVAL; + if (len > max_data_size) + len = max_data_size; + if (channel->ch >= channel->cl->tx_cfg.channels) + return -ECHRNG; + if (test_and_set_bit(HSC_CH_WRITE, &channel->flags)) + return -EBUSY; + msg = hsc_get_first_msg(channel, &channel->free_msgs_list); + if (!msg) { + clear_bit(HSC_CH_WRITE, &channel->flags); + return -ENOSPC; + } + if (copy_from_user(sg_virt(msg->sgt.sgl), (void __user *)buf, len)) { + ret = -EFAULT; + goto out; + } + hsc_msg_len_set(msg, len); + msg->complete = hsc_tx_completed; + msg->destructor = hsc_tx_msg_destructor; + ret = hsi_async_write(channel->cl, msg); + if (ret < 0) + goto out; + + ret = wait_event_interruptible(channel->tx_wait, + !list_empty(&channel->tx_msgs_queue)); + if (ret < 0) { + clear_bit(HSC_CH_WRITE, &channel->flags); + hsi_flush(channel->cl); + return -EINTR; + } + + msg = hsc_get_first_msg(channel, &channel->tx_msgs_queue); + if (msg) { + if (msg->status == HSI_STATUS_ERROR) + ret = -EIO; + else + ret = hsc_msg_len_get(msg); + + hsc_add_tail(channel, msg, &channel->free_msgs_list); + } +out: + clear_bit(HSC_CH_WRITE, &channel->flags); + + return ret; +} + +static long hsc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +{ + struct hsc_channel *channel = file->private_data; + unsigned int state; + struct hsc_rx_config rxc; + struct hsc_tx_config txc; + long ret = 0; + + switch (cmd) { + case HSC_RESET: + hsi_flush(channel->cl); + break; + case HSC_SET_PM: + if (copy_from_user(&state, (void __user *)arg, sizeof(state))) + return -EFAULT; + if (state == HSC_PM_DISABLE) { + if (test_and_set_bit(HSC_CH_WLINE, &channel->flags)) + return -EINVAL; + ret = hsi_start_tx(channel->cl); + } else if (state == HSC_PM_ENABLE) { + if (!test_and_clear_bit(HSC_CH_WLINE, &channel->flags)) + return -EINVAL; + ret = hsi_stop_tx(channel->cl); + } else { + ret = -EINVAL; + } + break; + case HSC_SEND_BREAK: + return hsc_break_send(channel->cl); + case HSC_SET_RX: + if (copy_from_user(&rxc, (void __user *)arg, sizeof(rxc))) + return -EFAULT; + return hsc_rx_set(channel->cl, &rxc); + case HSC_GET_RX: + hsc_rx_get(channel->cl, &rxc); + if (copy_to_user((void __user *)arg, &rxc, sizeof(rxc))) + return -EFAULT; + break; + case HSC_SET_TX: + if (copy_from_user(&txc, (void __user *)arg, sizeof(txc))) + return -EFAULT; + return hsc_tx_set(channel->cl, &txc); + case HSC_GET_TX: + hsc_tx_get(channel->cl, &txc); + if (copy_to_user((void __user *)arg, &txc, sizeof(txc))) + return -EFAULT; + break; + default: + return -ENOIOCTLCMD; + } + + return ret; +} + +static inline void __hsc_port_release(struct hsc_client_data *cl_data) +{ + BUG_ON(cl_data->usecnt == 0); + + if (--cl_data->usecnt == 0) { + hsi_flush(cl_data->cl); + hsi_release_port(cl_data->cl); + } +} + +static int hsc_open(struct inode *inode, struct file *file) +{ + struct hsc_client_data *cl_data; + struct hsc_channel *channel; + int ret = 0; + + pr_debug("open, minor = %d\n", iminor(inode)); + + cl_data = container_of(inode->i_cdev, struct hsc_client_data, cdev); + mutex_lock(&cl_data->lock); + channel = cl_data->channels + (iminor(inode) & HSC_CH_MASK); + + if (test_and_set_bit(HSC_CH_OPEN, &channel->flags)) { + ret = -EBUSY; + goto out; + } + /* + * Check if we have already claimed the port associated to the HSI + * client. If not then try to claim it, else increase its refcount + */ + if (cl_data->usecnt == 0) { + ret = hsi_claim_port(cl_data->cl, 0); + if (ret < 0) + goto out; + hsi_setup(cl_data->cl); + } + cl_data->usecnt++; + + ret = hsc_msgs_alloc(channel); + if (ret < 0) { + __hsc_port_release(cl_data); + goto out; + } + + file->private_data = channel; + mutex_unlock(&cl_data->lock); + + return ret; +out: + mutex_unlock(&cl_data->lock); + + return ret; +} + +static int hsc_release(struct inode *inode __maybe_unused, struct file *file) +{ + struct hsc_channel *channel = file->private_data; + struct hsc_client_data *cl_data = channel->cl_data; + + mutex_lock(&cl_data->lock); + file->private_data = NULL; + if (test_and_clear_bit(HSC_CH_WLINE, &channel->flags)) + hsi_stop_tx(channel->cl); + __hsc_port_release(cl_data); + hsc_reset_list(channel, &channel->rx_msgs_queue); + hsc_reset_list(channel, &channel->tx_msgs_queue); + hsc_reset_list(channel, &channel->free_msgs_list); + clear_bit(HSC_CH_READ, &channel->flags); + clear_bit(HSC_CH_WRITE, &channel->flags); + clear_bit(HSC_CH_OPEN, &channel->flags); + wake_up(&channel->rx_wait); + wake_up(&channel->tx_wait); + mutex_unlock(&cl_data->lock); + + return 0; +} + +static const struct file_operations hsc_fops = { + .owner = THIS_MODULE, + .read = hsc_read, + .write = hsc_write, + .unlocked_ioctl = hsc_ioctl, + .open = hsc_open, + .release = hsc_release, +}; + +static void __devinit hsc_channel_init(struct hsc_channel *channel) +{ + init_waitqueue_head(&channel->rx_wait); + init_waitqueue_head(&channel->tx_wait); + spin_lock_init(&channel->lock); + INIT_LIST_HEAD(&channel->free_msgs_list); + INIT_LIST_HEAD(&channel->rx_msgs_queue); + INIT_LIST_HEAD(&channel->tx_msgs_queue); +} + +static int __devinit hsc_probe(struct device *dev) +{ + const char devname[] = "hsi_char"; + struct hsc_client_data *cl_data; + struct hsc_channel *channel; + struct hsi_client *cl = to_hsi_client(dev); + unsigned int hsc_baseminor; + dev_t hsc_dev; + int ret; + int i; + + cl_data = kzalloc(sizeof(*cl_data), GFP_KERNEL); + if (!cl_data) { + dev_err(dev, "Could not allocate hsc_client_data\n"); + return -ENOMEM; + } + hsc_baseminor = HSC_BASEMINOR(hsi_id(cl), hsi_port_id(cl)); + if (!hsc_major) { + ret = alloc_chrdev_region(&hsc_dev, hsc_baseminor, + HSC_DEVS, devname); + if (ret > 0) + hsc_major = MAJOR(hsc_dev); + } else { + hsc_dev = MKDEV(hsc_major, hsc_baseminor); + ret = register_chrdev_region(hsc_dev, HSC_DEVS, devname); + } + if (ret < 0) { + dev_err(dev, "Device %s allocation failed %d\n", + hsc_major ? "minor" : "major", ret); + goto out1; + } + mutex_init(&cl_data->lock); + hsi_client_set_drvdata(cl, cl_data); + cdev_init(&cl_data->cdev, &hsc_fops); + cl_data->cdev.owner = THIS_MODULE; + cl_data->cl = cl; + for (i = 0, channel = cl_data->channels; i < HSC_DEVS; i++, channel++) { + hsc_channel_init(channel); + channel->ch = i; + channel->cl = cl; + channel->cl_data = cl_data; + } + + /* 1 hsi client -> N char devices (one for each channel) */ + ret = cdev_add(&cl_data->cdev, hsc_dev, HSC_DEVS); + if (ret) { + dev_err(dev, "Could not add char device %d\n", ret); + goto out2; + } + + return 0; +out2: + unregister_chrdev_region(hsc_dev, HSC_DEVS); +out1: + kfree(cl_data); + + return ret; +} + +static int __devexit hsc_remove(struct device *dev) +{ + struct hsi_client *cl = to_hsi_client(dev); + struct hsc_client_data *cl_data = hsi_client_drvdata(cl); + dev_t hsc_dev = cl_data->cdev.dev; + + cdev_del(&cl_data->cdev); + unregister_chrdev_region(hsc_dev, HSC_DEVS); + hsi_client_set_drvdata(cl, NULL); + kfree(cl_data); + + return 0; +} + +static struct hsi_client_driver hsc_driver = { + .driver = { + .name = "hsi_char", + .owner = THIS_MODULE, + .probe = hsc_probe, + .remove = __devexit_p(hsc_remove), + }, +}; + +static int __init hsc_init(void) +{ + int ret; + + if ((max_data_size < 4) || (max_data_size > 0x10000) || + (max_data_size & (max_data_size - 1))) { + pr_err("Invalid max read/write data size"); + return -EINVAL; + } + + ret = hsi_register_client_driver(&hsc_driver); + if (ret) { + pr_err("Error while registering HSI/SSI driver %d", ret); + return ret; + } + + pr_info("HSI/SSI char device loaded\n"); + + return 0; +} +module_init(hsc_init); + +static void __exit hsc_exit(void) +{ + hsi_unregister_client_driver(&hsc_driver); + pr_info("HSI char device removed\n"); +} +module_exit(hsc_exit); + +MODULE_AUTHOR("Andras Domokos <andras.domokos@nokia.com>"); +MODULE_ALIAS("hsi:hsi_char"); +MODULE_DESCRIPTION("HSI character device"); +MODULE_LICENSE("GPL v2"); |