diff options
Diffstat (limited to 'drivers/char/shrm_char.c')
| -rw-r--r-- | drivers/char/shrm_char.c | 897 |
1 files changed, 897 insertions, 0 deletions
diff --git a/drivers/char/shrm_char.c b/drivers/char/shrm_char.c new file mode 100644 index 00000000000..e8f350e5da8 --- /dev/null +++ b/drivers/char/shrm_char.c @@ -0,0 +1,897 @@ +/* + * Copyright (C) ST-Ericsson SA 2010 + * + * Author: Biju Das <biju.das@stericsson.com> for ST-Ericsson + * Author: Kumar Sanghavi <kumar.sanghvi@stericsson.com> for ST-Ericsson + * Author: Arun Murthy <arun.murthy@stericsson.com> for ST-Ericsson + * License terms: GNU General Public License (GPL) version 2 + */ + +#include <linux/err.h> +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/poll.h> +#include <linux/slab.h> +#include <linux/mutex.h> +#include <linux/spinlock.h> +#include <linux/sched.h> +#include <linux/modem/shrm/shrm_driver.h> +#include <linux/modem/shrm/shrm_private.h> +#include <linux/modem/shrm/shrm_config.h> +#include <linux/modem/shrm/shrm.h> +#include <asm/atomic.h> + +#include <mach/isa_ioctl.h> + + +#define NAME "IPC_ISA" +/* L2 header for rtc_calibration device is 0xC8 and hence 0xC8 + 1 = 201 */ +#define MAX_L2_HEADERS 201 + +#define SIZE_OF_FIFO (512*1024) + +static u8 message_fifo[ISA_DEVICES][SIZE_OF_FIFO]; + +static u8 wr_rpc_msg[10*1024]; +static u8 wr_sec_msg[10*1024]; +static u8 wr_audio_msg[10*1024]; +static u8 wr_rtc_cal_msg[100]; + +struct map_device { + u8 l2_header; + u8 idx; + char *name; +}; + +static struct map_device map_dev[] = { + {ISI_MESSAGING, 0, "isi"}, + {RPC_MESSAGING, 1, "rpc"}, + {AUDIO_MESSAGING, 2, "modemaudio"}, + {SECURITY_MESSAGING, 3, "sec"}, + {COMMON_LOOPBACK_MESSAGING, 4, "common_loopback"}, + {AUDIO_LOOPBACK_MESSAGING, 5, "audio_loopback"}, + {CIQ_MESSAGING, 6, "ciq"}, + {RTC_CAL_MESSAGING, 7, "rtc_calibration"}, +}; + +/* + * int major:This variable is exported to user as module_param to specify + * major number at load time + */ +static int major; +module_param(major, int, 0); +MODULE_PARM_DESC(major, "Major device number"); +/* global fops mutex */ +static DEFINE_MUTEX(isa_lock); + +/** + * shrm_get_cdev_index() - return the index mapped to l2 header + * @l2_header: L2 header + * + * struct map_device maps the index(count) with the device L2 header. + * This function returns the index for the provided L2 header in case + * of success else -ve value. + */ +int shrm_get_cdev_index(u8 l2_header) +{ + u8 cnt; + for (cnt = 0; cnt < ISA_DEVICES; cnt++) { + if (map_dev[cnt].l2_header == l2_header) + return map_dev[cnt].idx; + } + return -EINVAL; +} + +/** + * shrm_get_cdev_l2header() - return l2_header mapped to the index + * @idx: index + * + * struct map_device maps the index(count) with the device L2 header. + * This function returns the L2 header for the given index in case + * of success else -ve value. + */ +int shrm_get_cdev_l2header(u8 idx) +{ + u8 cnt; + for (cnt = 0; cnt < ISA_DEVICES; cnt++) { + if (map_dev[cnt].idx == idx) + return map_dev[cnt].l2_header; + } + return -EINVAL; +} + +void shrm_char_reset_queues(struct shrm_dev *shrm) +{ + struct isadev_context *isadev; + struct isa_driver_context *isa_context; + struct queue_element *cur_msg = NULL; + struct list_head *cur_msg_ptr = NULL; + struct list_head *msg_ptr; + struct message_queue *q; + int no_dev; + + dev_info(shrm->dev, "%s: Resetting char device queues\n", __func__); + isa_context = shrm->isa_context; + for (no_dev = 0 ; no_dev < ISA_DEVICES ; no_dev++) { + isadev = &isa_context->isadev[no_dev]; + q = &isadev->dl_queue; + + spin_lock_bh(&q->update_lock); + /* empty out the msg queue */ + list_for_each_safe(cur_msg_ptr, msg_ptr, &q->msg_list) { + cur_msg = list_entry(cur_msg_ptr, + struct queue_element, entry); + list_del(cur_msg_ptr); + kfree(cur_msg); + } + + /* reset the msg queue pointers */ + q->size = SIZE_OF_FIFO; + q->readptr = 0; + q->writeptr = 0; + q->no = 0; + + /* wake up the blocking read/select */ + atomic_set(&q->q_rp, 1); + wake_up_interruptible(&q->wq_readable); + + spin_unlock_bh(&q->update_lock); + } +} + +/** + * create_queue() - To create FIFO for Tx and Rx message buffering. + * @q: message queue. + * @devicetype: device type 0-isi,1-rpc,2-audio,3-security, + * 4-common_loopback, 5-audio_loopback. + * @shrm: pointer to the shrm device information structure + * + * This function creates a FIFO buffer of n_bytes size using + * dma_alloc_coherent(). It also initializes all queue handling + * locks, queue management pointers. It also initializes message list + * which occupies this queue. + */ +static int create_queue(struct message_queue *q, u32 devicetype, + struct shrm_dev *shrm) +{ + q->fifo_base = (u8 *)&message_fifo[devicetype]; + q->size = SIZE_OF_FIFO; + q->readptr = 0; + q->writeptr = 0; + q->no = 0; + q->shrm = shrm; + spin_lock_init(&q->update_lock); + INIT_LIST_HEAD(&q->msg_list); + init_waitqueue_head(&q->wq_readable); + atomic_set(&q->q_rp, 0); + + return 0; +} + +static void delete_queue(struct message_queue *q) +{ + q->size = 0; + q->readptr = 0; + q->writeptr = 0; +} + +/** + * add_msg_to_queue() - Add a message inside queue + * @q: message queue + * @size: size in bytes + * + * This function tries to allocate n_bytes of size in FIFO q. + * It returns negative number when no memory can be allocated + * currently. + */ +int add_msg_to_queue(struct message_queue *q, u32 size) +{ + struct queue_element *new_msg = NULL; + struct shrm_dev *shrm = q->shrm; + + dev_dbg(shrm->dev, "%s IN q->writeptr=%d\n", __func__, q->writeptr); + new_msg = kmalloc(sizeof(struct queue_element), GFP_ATOMIC); + if (new_msg == NULL) { + dev_err(shrm->dev, "unable to allocate memory\n"); + return -ENOMEM; + } + new_msg->offset = q->writeptr; + new_msg->size = size; + new_msg->no = q->no++; + + /* check for overflow condition */ + if (q->readptr <= q->writeptr) { + if (((q->writeptr-q->readptr) + size) >= q->size) { + dev_err(shrm->dev, "Buffer overflow !!\n"); + BUG_ON(((q->writeptr-q->readptr) + size) >= q->size); + } + } else { + if ((q->writeptr + size) >= q->readptr) { + dev_err(shrm->dev, "Buffer overflow !!\n"); + BUG_ON((q->writeptr + size) >= q->readptr); + } + } + q->writeptr = (q->writeptr + size) % q->size; + if (list_empty(&q->msg_list)) { + list_add_tail(&new_msg->entry, &q->msg_list); + /* There can be 2 blocking calls read and another select */ + atomic_set(&q->q_rp, 1); + wake_up_interruptible(&q->wq_readable); + } else + list_add_tail(&new_msg->entry, &q->msg_list); + + dev_dbg(shrm->dev, "%s OUT\n", __func__); + return 0; +} + +/** + * remove_msg_from_queue() - To remove a message from the msg queue. + * @q: message queue + * + * This function delets a message from the message list associated with message + * queue q and also updates read ptr. + * If the message list is empty, then, event is set to block the select and + * read calls of the paricular queue. + * + * The message list is FIFO style and message is always added to tail and + * removed from head. + */ +int remove_msg_from_queue(struct message_queue *q) +{ + struct queue_element *old_msg = NULL; + struct shrm_dev *shrm = q->shrm; + struct list_head *msg_ptr = NULL; + struct list_head *old_msg_ptr = NULL; + + dev_dbg(shrm->dev, "%s IN q->readptr %d\n", __func__, q->readptr); + + list_for_each_safe(old_msg_ptr, msg_ptr, &q->msg_list) { + old_msg = list_entry(old_msg_ptr, struct queue_element, entry); + if (old_msg == NULL) { + dev_err(shrm->dev, "no message found\n"); + return -EFAULT; + } + list_del(old_msg_ptr); + q->readptr = (q->readptr + old_msg->size)%q->size; + kfree(old_msg); + break; + } + if (list_empty(&q->msg_list)) { + dev_dbg(shrm->dev, "List is empty setting RP= 0\n"); + atomic_set(&q->q_rp, 0); + } + + dev_dbg(shrm->dev, "%s OUT\n", __func__); + return 0; +} + +/** + * get_size_of_new_msg() - retrieve new message from message list + * @q: message queue + * + * This function will retrieve most recent message from the corresponding + * queue list. New message is always retrieved from head side. + * It returns new message no, offset if FIFO and size. + */ +int get_size_of_new_msg(struct message_queue *q) +{ + struct queue_element *new_msg = NULL; + struct list_head *msg_list; + struct shrm_dev *shrm = q->shrm; + int size = 0; + + dev_dbg(shrm->dev, "%s IN\n", __func__); + + spin_lock_bh(&q->update_lock); + list_for_each(msg_list, &q->msg_list) { + new_msg = list_entry(msg_list, struct queue_element, entry); + if (new_msg == NULL) { + spin_unlock_bh(&q->update_lock); + dev_err(shrm->dev, "no message found\n"); + return -EFAULT; + } + size = new_msg->size; + break; + } + spin_unlock_bh(&q->update_lock); + + dev_dbg(shrm->dev, "%s OUT\n", __func__); + return size; +} + +/** + * isa_select() - shrm char interface driver select interface + * @filp: file descriptor pointer + * @wait: poll_table_struct pointer + * + * This function is used to perform non-blocking read operations. It allows + * a process to determine whether it can read from one or more open files + * without blocking. These calls can also block a process until any of a + * given set of file descriptors becomes available for reading. + * If a file is ready to read, POLLIN | POLLRDNORM bitmask is returned. + * The driver method is called whenever the user-space program performs a select + * system call involving a file descriptor associated with the driver. + */ +static u32 isa_select(struct file *filp, + struct poll_table_struct *wait) +{ + struct isadev_context *isadev = filp->private_data; + struct shrm_dev *shrm = isadev->dl_queue.shrm; + struct message_queue *q; + u32 mask = 0; + u32 m = iminor(filp->f_path.dentry->d_inode); + u8 idx = shrm_get_cdev_index(m); + + dev_dbg(shrm->dev, "%s IN\n", __func__); + + if (shrm->msr_flag) + return -ENODEV; + + if (isadev->device_id != idx) + return -1; + + q = &isadev->dl_queue; + poll_wait(filp, &q->wq_readable, wait); + if (atomic_read(&q->q_rp) == 1) + mask = POLLIN | POLLRDNORM; + + dev_dbg(shrm->dev, "%s OUT\n", __func__); + return mask; +} + +/** + * isa_read() - Read from device + * @filp: file descriptor + * @buf: user buffer pointer + * @len: size of requested data transfer + * @ppos: not used + * + * It reads a oldest message from queue and copies it into user buffer and + * returns its size. + * If there is no message present in queue, then it blocks until new data is + * available. + */ +ssize_t isa_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos) +{ + u32 size = 0; + int ret; + char *psrc; + struct isadev_context *isadev = (struct isadev_context *) + filp->private_data; + struct shrm_dev *shrm = isadev->dl_queue.shrm; + struct message_queue *q; + u32 msgsize; + + dev_dbg(shrm->dev, "%s IN\n", __func__); + + if (len <= 0) + return -EFAULT; + + q = &isadev->dl_queue; + + if (shrm->msr_flag) { + atomic_set(&q->q_rp, 0); + return -ENODEV; + } + + spin_lock_bh(&q->update_lock); + if (list_empty(&q->msg_list)) { + spin_unlock_bh(&q->update_lock); + dev_dbg(shrm->dev, "Waiting for Data\n"); + if (wait_event_interruptible(q->wq_readable, + atomic_read(&q->q_rp) == 1)) + return -ERESTARTSYS; + } else + spin_unlock_bh(&q->update_lock); + + if (shrm->msr_flag) { + atomic_set(&q->q_rp, 0); + return -ENODEV; + } + + msgsize = get_size_of_new_msg(q); + + if (len < msgsize) + return -EINVAL; + + if ((q->readptr+msgsize) >= q->size) { + dev_dbg(shrm->dev, "Inside Loop Back\n"); + psrc = (char *)buf; + size = (q->size-q->readptr); + /* Copy First Part of msg */ + if (copy_to_user(psrc, + (u8 *)(q->fifo_base+q->readptr), + size)) { + dev_err(shrm->dev, "copy_to_user failed\n"); + return -EFAULT; + } + psrc += size; + /* Copy Second Part of msg at the top of fifo */ + if (copy_to_user(psrc, + (u8 *)(q->fifo_base), + (msgsize-size))) { + dev_err(shrm->dev, "copy_to_user failed\n"); + return -EFAULT; + } + } else { + if (copy_to_user(buf, + (u8 *)(q->fifo_base + q->readptr), + msgsize)) { + dev_err(shrm->dev, "copy_to_user failed\n"); + return -EFAULT; + } + } + spin_lock_bh(&q->update_lock); + ret = remove_msg_from_queue(q); + if (ret < 0) { + dev_err(shrm->dev, + "Remove msg from message queue failed\n"); + msgsize = ret; + } + spin_unlock_bh(&q->update_lock); + dev_dbg(shrm->dev, "%s OUT\n", __func__); + return msgsize; +} + +/** + * isa_write() - Write to shrm char device + * @filp: file descriptor + * @buf: user buffer pointer + * @len: size of requested data transfer + * @ppos: not used + * + * It checks if there is space available in queue, and copies the message + * inside queue. If there is no space, it blocks until space becomes available. + * It also schedules transfer thread to transmit the newly added message. + */ +ssize_t isa_write(struct file *filp, const char __user *buf, + size_t len, loff_t *ppos) +{ + struct isadev_context *isadev = filp->private_data; + struct shrm_dev *shrm = isadev->dl_queue.shrm; + struct message_queue *q; + void *addr = 0; + int err, l2_header; + int ret = 0; + + dev_dbg(shrm->dev, "%s IN\n", __func__); + + if (len <= 0 || buf == NULL) + return -EFAULT; + q = &isadev->dl_queue; + l2_header = shrm_get_cdev_l2header(isadev->device_id); + if (l2_header < 0) { + dev_err(shrm->dev, "failed to get L2 header\n"); + return l2_header; + } + + switch (l2_header) { + case RPC_MESSAGING: + dev_dbg(shrm->dev, "RPC\n"); + addr = (void *)wr_rpc_msg; + break; + case AUDIO_MESSAGING: + dev_dbg(shrm->dev, "Audio\n"); + addr = (void *)wr_audio_msg; + break; + case SECURITY_MESSAGING: + dev_dbg(shrm->dev, "Security\n"); + addr = (void *)wr_sec_msg; + break; + case COMMON_LOOPBACK_MESSAGING: + dev_dbg(shrm->dev, "Common loopback\n"); + addr = isadev->addr; + break; + case AUDIO_LOOPBACK_MESSAGING: + dev_dbg(shrm->dev, "Audio loopback\n"); + addr = isadev->addr; + break; + case CIQ_MESSAGING: + dev_dbg(shrm->dev, "CIQ\n"); + addr = isadev->addr; + break; + case RTC_CAL_MESSAGING: + dev_dbg(shrm->dev, "isa_write(): RTC Calibration\n"); + addr = (void *)wr_rtc_cal_msg; + break; + default: + dev_dbg(shrm->dev, "Wrong device\n"); + return -EFAULT; + } + + if (copy_from_user(addr, buf, len)) { + dev_err(shrm->dev, "copy_from_user failed\n"); + return -EFAULT; + } + /* Write msg to Fifo */ + if ((l2_header == AUDIO_MESSAGING) || + (l2_header == AUDIO_LOOPBACK_MESSAGING)) { + mutex_lock(&shrm->isa_context->tx_audio_mutex); + err = shm_write_msg(shrm, l2_header, addr, len); + if (!err) + ret = len; + else + ret = err; + mutex_unlock(&shrm->isa_context->tx_audio_mutex); + } else { + spin_lock_bh(&shrm->isa_context->common_tx); + err = shm_write_msg(shrm, l2_header, addr, len); + if (!err) + ret = len; + else + ret = err; + spin_unlock_bh(&shrm->isa_context->common_tx); + } + dev_dbg(shrm->dev, "%s OUT\n", __func__); + return ret; +} + +/** + * isa_ioctl() - To handle different ioctl commands supported by driver. + * @inode: structure is used by the kernel internally to represent files + * @filp: file descriptor pointer + * @cmd: ioctl command + * @arg: input param + * + * Following ioctls are supported by this driver. + * DLP_IOCTL_ALLOCATE_BUFFER - To allocate buffer for new uplink message. + * This ioctl is called with required message size. It returns offset for + * the allocates space in the queue. DLP_IOCTL_PUT_MESSAGE - To indicate + * new uplink message available in queuq for transmission. Message is copied + * from offset location returned by previous ioctl before calling this ioctl. + * DLP_IOCTL_GET_MESSAGE - To check if any downlink message is available in + * queue. It returns offset for new message inside queue. + * DLP_IOCTL_DEALLOCATE_BUFFER - To deallocate any buffer allocate for + * downlink message once the message is copied. Message is copied from offset + * location returned by previous ioctl before calling this ioctl. + */ +static long isa_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) +{ + long err = 0; + struct isadev_context *isadev = filp->private_data; + struct shrm_dev *shrm = isadev->dl_queue.shrm; + u32 m = iminor(filp->f_path.dentry->d_inode); + + isadev = (struct isadev_context *)filp->private_data; + + if (isadev->device_id != m) + return -EINVAL; + + switch (cmd) { + case DLP_IOC_ALLOCATE_BUFFER: + dev_dbg(shrm->dev, "DLP_IOC_ALLOCATE_BUFFER\n"); + break; + case DLP_IOC_PUT_MESSAGE: + dev_dbg(shrm->dev, "DLP_IOC_PUT_MESSAGE\n"); + break; + case DLP_IOC_GET_MESSAGE: + dev_dbg(shrm->dev, "DLP_IOC_GET_MESSAGE\n"); + break; + case DLP_IOC_DEALLOCATE_BUFFER: + dev_dbg(shrm->dev, "DLP_IOC_DEALLOCATE_BUFFER\n"); + break; + default: + dev_dbg(shrm->dev, "Unknown IOCTL\n"); + err = -EFAULT; + break; + } + return err; +} +/** + * isa_mmap() - Maps kernel queue memory to user space. + * @filp: file descriptor pointer + * @vma: virtual area memory structure. + * + * This function maps kernel FIFO into user space. This function + * shall be called twice to map both uplink and downlink buffers. + */ +static int isa_mmap(struct file *filp, struct vm_area_struct *vma) +{ + struct isadev_context *isadev = filp->private_data; + struct shrm_dev *shrm = isadev->dl_queue.shrm; + + u32 m = iminor(filp->f_path.dentry->d_inode); + dev_dbg(shrm->dev, "%s %d\n", __func__, m); + + return 0; +} + +/** + * isa_close() - Close device file + * @inode: structure is used by the kernel internally to represent files + * @filp: device file descriptor + * + * This function deletes structues associated with this file, deletes + * queues, flushes and destroys workqueus and closes this file. + * It also unregisters itself from l2mux driver. + */ +static int isa_close(struct inode *inode, struct file *filp) +{ + struct isadev_context *isadev = filp->private_data; + struct shrm_dev *shrm = isadev->dl_queue.shrm; + struct isa_driver_context *isa_context = shrm->isa_context; + u8 m; + int idx; + + mutex_lock(&isa_lock); + m = iminor(filp->f_path.dentry->d_inode); + idx = shrm_get_cdev_index(m); + if (idx < 0) { + dev_err(shrm->dev, "failed to get index\n"); + mutex_unlock(&isa_lock); + return idx; + } + dev_dbg(shrm->dev, "isa_close %d", m); + + if (atomic_dec_and_test(&isa_context->is_open[idx])) { + atomic_inc(&isa_context->is_open[idx]); + dev_err(shrm->dev, "Device not opened yet\n"); + mutex_unlock(&isa_lock); + return -ENODEV; + } + atomic_set(&isa_context->is_open[idx], 1); + + switch (m) { + case RPC_MESSAGING: + dev_info(shrm->dev, "Close RPC_MESSAGING Device\n"); + break; + case AUDIO_MESSAGING: + dev_info(shrm->dev, "Close AUDIO_MESSAGING Device\n"); + break; + case SECURITY_MESSAGING: + dev_info(shrm->dev, "CLose SECURITY_MESSAGING Device\n"); + break; + case COMMON_LOOPBACK_MESSAGING: + kfree(isadev->addr); + dev_info(shrm->dev, "Close COMMON_LOOPBACK_MESSAGING Device\n"); + break; + case AUDIO_LOOPBACK_MESSAGING: + kfree(isadev->addr); + dev_info(shrm->dev, "Close AUDIO_LOOPBACK_MESSAGING Device\n"); + break; + case CIQ_MESSAGING: + kfree(isadev->addr); + dev_info(shrm->dev, "Close CIQ_MESSAGING Device\n"); + break; + case RTC_CAL_MESSAGING: + dev_info(shrm->dev, "Close RTC_CAL_MESSAGING Device\n"); + break; + default: + dev_info(shrm->dev, "No such device present\n"); + mutex_unlock(&isa_lock); + return -ENODEV; + }; + mutex_unlock(&isa_lock); + return 0; +} +/** + * isa_open() - Open device file + * @inode: structure is used by the kernel internally to represent files + * @filp: device file descriptor + * + * This function performs initialization tasks needed to open SHM channel. + * Following tasks are performed. + * -return if device is already opened + * -create uplink FIFO + * -create downlink FIFO + * -init delayed workqueue thread + * -register to l2mux driver + */ +static int isa_open(struct inode *inode, struct file *filp) +{ + int err = 0; + u8 m; + int idx; + struct isadev_context *isadev; + struct isa_driver_context *isa_context = container_of( + inode->i_cdev, + struct isa_driver_context, + cdev); + struct shrm_dev *shrm = isa_context->isadev->dl_queue.shrm; + + dev_dbg(shrm->dev, "%s IN\n", __func__); + + if (get_boot_state() != BOOT_DONE) { + dev_err(shrm->dev, "Boot is not done\n"); + return -EBUSY; + } + mutex_lock(&isa_lock); + m = iminor(inode); + + if ((m != RPC_MESSAGING) && + (m != AUDIO_LOOPBACK_MESSAGING) && + (m != COMMON_LOOPBACK_MESSAGING) && + (m != AUDIO_MESSAGING) && + (m != SECURITY_MESSAGING) && + (m != CIQ_MESSAGING) && + (m != RTC_CAL_MESSAGING)) { + dev_err(shrm->dev, "No such device present\n"); + mutex_unlock(&isa_lock); + return -ENODEV; + } + idx = shrm_get_cdev_index(m); + if (idx < 0) { + dev_err(shrm->dev, "failed to get index\n"); + mutex_unlock(&isa_lock); + return idx; + } + if (!atomic_dec_and_test(&isa_context->is_open[idx])) { + atomic_inc(&isa_context->is_open[idx]); + dev_err(shrm->dev, "Device already opened\n"); + mutex_unlock(&isa_lock); + return -EBUSY; + } + isadev = &isa_context->isadev[idx]; + if (filp != NULL) + filp->private_data = isadev; + + switch (m) { + case RPC_MESSAGING: + dev_info(shrm->dev, "Open RPC_MESSAGING Device\n"); + break; + case AUDIO_MESSAGING: + dev_info(shrm->dev, "Open AUDIO_MESSAGING Device\n"); + break; + case SECURITY_MESSAGING: + dev_info(shrm->dev, "Open SECURITY_MESSAGING Device\n"); + break; + case COMMON_LOOPBACK_MESSAGING: + isadev->addr = kzalloc(10 * 1024, GFP_KERNEL); + if (!isadev->addr) { + mutex_unlock(&isa_lock); + return -ENOMEM; + } + dev_info(shrm->dev, "Open COMMON_LOOPBACK_MESSAGING Device\n"); + break; + case AUDIO_LOOPBACK_MESSAGING: + isadev->addr = kzalloc(10 * 1024, GFP_KERNEL); + if (!isadev->addr) { + mutex_unlock(&isa_lock); + return -ENOMEM; + } + dev_info(shrm->dev, "Open AUDIO_LOOPBACK_MESSAGING Device\n"); + break; + case CIQ_MESSAGING: + isadev->addr = kzalloc(10 * 1024, GFP_KERNEL); + if (!isadev->addr) { + mutex_unlock(&isa_lock); + return -ENOMEM; + } + dev_info(shrm->dev, "Open CIQ_MESSAGING Device\n"); + break; + case RTC_CAL_MESSAGING: + dev_info(shrm->dev, "Open RTC_CAL_MESSAGING Device\n"); + break; + }; + + mutex_unlock(&isa_lock); + dev_dbg(shrm->dev, "%s OUT\n", __func__); + return err; +} + +const struct file_operations isa_fops = { + .owner = THIS_MODULE, + .open = isa_open, + .release = isa_close, + .unlocked_ioctl = isa_ioctl, + .mmap = isa_mmap, + .read = isa_read, + .write = isa_write, + .poll = isa_select, +}; + +/** + * isa_init() - module insertion function + * @shrm: pointer to the shrm device information structure + * + * This function registers module as a character driver using + * register_chrdev_region() or alloc_chrdev_region. It adds this + * driver to system using cdev_add() call. Major number is dynamically + * allocated using alloc_chrdev_region() by default or left to user to specify + * it during load time. For this variable major is used as module_param + * Nodes to be created using + * mknod /dev/isi c $major 0 + * mknod /dev/rpc c $major 1 + * mknod /dev/audio c $major 2 + * mknod /dev/sec c $major 3 + */ +int isa_init(struct shrm_dev *shrm) +{ + dev_t dev_id; + int retval, no_dev; + struct isadev_context *isadev; + struct isa_driver_context *isa_context; + + isa_context = kzalloc(sizeof(struct isa_driver_context), + GFP_KERNEL); + if (isa_context == NULL) { + dev_err(shrm->dev, "Failed to alloc memory\n"); + return -ENOMEM; + } + shrm->isa_context = isa_context; + if (major) { + dev_id = MKDEV(major, MAX_L2_HEADERS); + retval = register_chrdev_region(dev_id, ISA_DEVICES, NAME); + } else { + /* + * L2 header of loopback device is 192(0xc0). As per the shrm + * protocol the minor id of the deivce is mapped to the + * L2 header. + */ + retval = alloc_chrdev_region(&dev_id, 0, MAX_L2_HEADERS, NAME); + major = MAJOR(dev_id); + } + dev_dbg(shrm->dev, " major %d\n", major); + + cdev_init(&isa_context->cdev, &isa_fops); + isa_context->cdev.owner = THIS_MODULE; + retval = cdev_add(&isa_context->cdev, dev_id, MAX_L2_HEADERS); + if (retval) { + dev_err(shrm->dev, "Failed to add char device\n"); + return retval; + } + /* create class and device */ + isa_context->shm_class = class_create(THIS_MODULE, NAME); + if (IS_ERR(isa_context->shm_class)) { + dev_err(shrm->dev, "Error creating shrm class\n"); + cdev_del(&isa_context->cdev); + retval = PTR_ERR(isa_context->shm_class); + kfree(isa_context); + return retval; + } + + for (no_dev = 0; no_dev < ISA_DEVICES; no_dev++) { + atomic_set(&isa_context->is_open[no_dev], 1); + device_create(isa_context->shm_class, NULL, + MKDEV(MAJOR(dev_id), + map_dev[no_dev].l2_header), NULL, + map_dev[no_dev].name); + } + + isa_context->isadev = kzalloc(sizeof + (struct isadev_context)*ISA_DEVICES, + GFP_KERNEL); + if (isa_context->isadev == NULL) { + dev_err(shrm->dev, "Failed to alloc memory\n"); + return -ENOMEM; + } + for (no_dev = 0 ; no_dev < ISA_DEVICES ; no_dev++) { + isadev = &isa_context->isadev[no_dev]; + isadev->device_id = no_dev; + retval = create_queue(&isadev->dl_queue, + isadev->device_id, shrm); + + if (retval < 0) { + dev_err(shrm->dev, "create dl_queue failed\n"); + delete_queue(&isadev->dl_queue); + kfree(isadev); + return retval; + } + } + mutex_init(&isa_context->tx_audio_mutex); + spin_lock_init(&isa_context->common_tx); + dev_dbg(shrm->dev, " SHM Char Driver added\n"); + return retval; +} + +void isa_exit(struct shrm_dev *shrm) +{ + int no_dev; + struct isadev_context *isadev; + struct isa_driver_context *isa_context = shrm->isa_context; + dev_t dev_id = MKDEV(major, 0); + + for (no_dev = 0 ; no_dev < ISA_DEVICES ; no_dev++) { + device_destroy(isa_context->shm_class, + MKDEV(MAJOR(dev_id), + map_dev[no_dev].l2_header)); + isadev = &isa_context->isadev[no_dev]; + delete_queue(&isadev->dl_queue); + kfree(isadev); + } + class_destroy(isa_context->shm_class); + cdev_del(&isa_context->cdev); + unregister_chrdev_region(dev_id, ISA_DEVICES); + kfree(isa_context); + dev_dbg(shrm->dev, " SHM Char Driver removed\n"); +} |