/* Resets the state of the passed instance */
static void reset_mailbox(struct labx_mailbox *mailbox) {
/* Disable the instance, and wipe its registers */
disable_mailbox(mailbox);
}
/* Function containing the "meat" of the probe mechanism - this is used by
* the OpenFirmware probe as well as the standard platform device mechanism.
* @param name - Name of the instance
* @param pdev - Platform device structure
* @param addressRange - Resource describing the hardware's I/O range
* @param irq - Resource describing the hardware's IRQ
*/
static int spi_mailbox_probe(const char *name,
struct platform_device *pdev,
struct resource *addressRange,
struct resource *irq) {
struct spi_mailbox *mailbox;
int returnValue;
/* Create and populate a device structure */
mailbox = (struct spi_mailbox*) kmalloc(sizeof(struct spi_mailbox), GFP_KERNEL);
if(!mailbox) return(-ENOMEM);
/* Request and map the device's I/O memory region into uncacheable space */
mailbox->physicalAddress = addressRange->start;
mailbox->addressRangeSize = ((addressRange->end - addressRange->start) + 1);
snprintf(mailbox->name, NAME_MAX_SIZE, "%s", name);
mailbox->name[NAME_MAX_SIZE - 1] = '\0';
if(request_mem_region(mailbox->physicalAddress, mailbox->addressRangeSize,
mailbox->name) == NULL) {
returnValue = -ENOMEM;
goto free;
}
mailbox->virtualAddress =
(void*) ioremap_nocache(mailbox->physicalAddress, mailbox->addressRangeSize);
if(!mailbox->virtualAddress) {
returnValue = -ENOMEM;
goto release;
}
/* Ensure that the mailbox and its interrupts are disabled */
disable_mailbox(mailbox);
XIo_Out32(REGISTER_ADDRESS(mailbox, IRQ_MASK_REG), NO_IRQS);
/* Retain the IRQ and register our handler, if an IRQ resource was supplied. */
if(irq != NULL) {
mailbox->irq = irq->start;
returnValue = request_irq(mailbox->irq, &biamp_spi_mailbox_interrupt, IRQF_DISABLED,
mailbox->name, mailbox);
if (returnValue) {
printk(KERN_ERR "%s : Could not allocate Biamp SPI Mailbox interrupt (%d).\n",
mailbox->name, mailbox->irq);
goto unmap;
}
} else mailbox->irq = NO_IRQ_SUPPLIED;
/* Announce the device */
printk(KERN_INFO "%s: Found Biamp mailbox at 0x%08X, ",
mailbox->name, (uint32_t)mailbox->physicalAddress);
if(mailbox->irq == NO_IRQ_SUPPLIED) {
printk("polled interlocks\n");
} else {
printk("IRQ %d\n", mailbox->irq);
}
/* Initialize other resources */
spin_lock_init(&mailbox->mutex);
mailbox->opened = false;
/* Provide navigation between the device structures */
platform_set_drvdata(pdev, mailbox);
mailbox->pdev = pdev;
/* Reset the state of the mailbox */
reset_mailbox(mailbox);
/* Add as a character device to make the instance available for use */
cdev_init(&mailbox->cdev, &spi_mailbox_fops);
mailbox->cdev.owner = THIS_MODULE;
kobject_set_name(&mailbox->cdev.kobj, "%s%d", mailbox->name, mailbox->instanceNumber);
mailbox->instanceNumber = instanceCount++;
cdev_add(&mailbox->cdev, MKDEV(DRIVER_MAJOR, mailbox->instanceNumber), 1);
/* Initialize the waitqueue used for synchronized writes */
init_waitqueue_head(&(mailbox->messageReadQueue));
/* Now that the device is configured, enable interrupts if they are to be used */
if(mailbox->irq != NO_IRQ_SUPPLIED) {
XIo_Out32(REGISTER_ADDRESS(mailbox, IRQ_FLAGS_REG), ALL_IRQS);
XIo_Out32(REGISTER_ADDRESS(mailbox, IRQ_MASK_REG), IRQ_S2H_MSG_RX);
}
DBG("Mailbox initialized\n");
/* Return success */
return(0);
unmap:
iounmap(mailbox->virtualAddress);
release:
release_mem_region(mailbox->physicalAddress, mailbox->addressRangeSize);
free:
kfree(mailbox);
return(returnValue);
}
/* Function containing the "meat" of the probe mechanism - this is used by
* the OpenFirmware probe as well as the standard platform device mechanism.
* @param name - Name of the instance
* @param pdev - Platform device structure
* @param addressRange - Resource describing the hardware's I/O range
* @param irq - Resource describing the hardware's IRQ
*/
static int mailbox_probe(const char *name,
struct platform_device *pdev,
struct resource *addressRange,
struct resource *irq) {
struct labx_mailbox *mailbox;
int returnValue;
int i;
/* Create and populate a device structure */
mailbox = (struct labx_mailbox*) kmalloc(sizeof(struct labx_mailbox), GFP_KERNEL);
if(!mailbox) return(-ENOMEM);
/* Request and map the device's I/O memory region into uncacheable space */
mailbox->physicalAddress = addressRange->start;
mailbox->addressRangeSize = ((addressRange->end - addressRange->start) + 1);
snprintf(mailbox->name, NAME_MAX_SIZE, "%s", name);
mailbox->name[NAME_MAX_SIZE - 1] = '\0';
if(request_mem_region(mailbox->physicalAddress, mailbox->addressRangeSize,
mailbox->name) == NULL) {
returnValue = -ENOMEM;
goto free;
}
mailbox->virtualAddress =
(void*) ioremap_nocache(mailbox->physicalAddress, mailbox->addressRangeSize);
if(!mailbox->virtualAddress) {
returnValue = -ENOMEM;
goto release;
}
/* Ensure that the mailbox and its interrupts are disabled */
disable_mailbox(mailbox);
XIo_Out32(REGISTER_ADDRESS(mailbox, SUPRV_IRQ_MASK_REG), NO_IRQS);
/* Clear the message ready flag for the first time */
mailbox->messageReadyFlag = MESSAGE_NOT_READY;
/* Retain the IRQ and register our handler, if an IRQ resource was supplied. */
if(irq != NULL) {
mailbox->irq = irq->start;
returnValue = request_irq(mailbox->irq, &mailbox_interrupt, IRQF_DISABLED,
mailbox->name, mailbox);
if (returnValue) {
printk(KERN_ERR "%s : Could not allocate Mailbox interrupt (%d).\n",
mailbox->name, mailbox->irq);
goto unmap;
}
} else mailbox->irq = NO_IRQ_SUPPLIED;
/* Announce the device */
printk(KERN_INFO "%s: Found mailbox at 0x%08X, ",
mailbox->name, (uint32_t)mailbox->physicalAddress);
if(mailbox->irq == NO_IRQ_SUPPLIED) {
printk("polled interlocks\n");
} else {
printk("IRQ %d\n", mailbox->irq);
}
/* Initialize other resources */
spin_lock_init(&mailbox->mutex);
mailbox->opened = true;
/* Provide navigation between the device structures */
platform_set_drvdata(pdev, mailbox);
mailbox->pdev = pdev;
/* Reset the state of the mailbox */
reset_mailbox(mailbox);
/* Initialize the waitqueue used for synchronized writes */
init_waitqueue_head(&(mailbox->messageReadQueue));
/* Initialize the netlink state and start the thread */
mailbox->netlinkSequence = 0;
mailbox->netlinkTask = kthread_run(netlink_thread, (void*)mailbox, "%s:netlink", mailbox->name);
if (IS_ERR(mailbox->netlinkTask)) {
printk(KERN_ERR "Mailbox netlink task creation failed.\n");
returnValue = -EIO;
goto free;
}
/* Now that the device is configured, enable interrupts if they are to be used */
if(mailbox->irq != NO_IRQ_SUPPLIED) {
XIo_Out32(REGISTER_ADDRESS(mailbox, SUPRV_IRQ_MASK_REG), ALL_IRQS);
XIo_Out32(REGISTER_ADDRESS(mailbox, SUPRV_IRQ_FLAGS_REG), ALL_IRQS);
}
// Add the mailbox instance to the list of current devices
for(i=0;i<MAX_MAILBOX_DEVICES;i++) {
if(NULL == labx_mailboxes[i]) {
labx_mailboxes[i] = mailbox;
printk("Adding mailbox: %s\n", labx_mailboxes[i]->name);
break;
}
}
DBG("Mailbox initialized\n");
/* Return success */
return(0);
unmap:
iounmap(mailbox->virtualAddress);
release:
release_mem_region(mailbox->physicalAddress, mailbox->addressRangeSize);
free:
kfree(mailbox);
return(returnValue);
}
/* I/O control operations for the driver */
static int spi_mailbox_ioctl(struct inode *inode, struct file *flip,
unsigned int command, unsigned long arg)
{
// Switch on the request
int returnValue = 0;
struct spi_mailbox *mailbox = (struct spi_mailbox*)flip->private_data;
switch(command) {
case IOC_START_MBOX:
enable_mailbox(mailbox);
break;
case IOC_STOP_MBOX:
disable_mailbox(mailbox);
break;
case IOC_READ_MBOX:
{
MessageData userMessage;
MessageData localMessage;
/* Copy into our local descriptor, then obtain buffer pointer from userland */
if(copy_from_user(&userMessage, (void __user*)arg, sizeof(userMessage)) != 0) {
return(-EFAULT);
}
returnValue = await_message_ready(mailbox);
if(returnValue < 0) {
return(returnValue);
}
localMessage.length = read_mailbox_message(mailbox, messageBuffer);
if(copy_to_user((void __user*)userMessage.messageContent, messageBuffer,
(min(userMessage.length, localMessage.length))) != 0) {
return(-EFAULT);
}
if(copy_to_user((void __user*)arg, &localMessage.length, sizeof(localMessage.length)) != 0 ) {
return(-EFAULT);
}
}
break;
case IOC_WRITE_RESP:
{
MessageData userMessage;
/* Copy into our local descriptor, then obtain buffer pointer from userland */
if(copy_from_user(&userMessage, (void __user*)arg, sizeof(userMessage)) != 0) {
return(-EFAULT);
}
if(userMessage.length > MAX_MESSAGE_DATA) {
return(-EINVAL);
}
if(copy_from_user(messageBuffer, (void __user*)userMessage.messageContent,
userMessage.length) != 0) {
return(-EFAULT);
}
userMessage.messageContent = messageBuffer;
send_message_response(mailbox, &userMessage);
}
break;
case IOC_SET_SPI_IRQ_FLAGS:
{
set_spi_irq_flags(mailbox, ((uint8_t)arg));
}
break;
case IOC_CLEAR_SPI_IRQ_FLAGS:
{
clear_spi_irq_flags(mailbox, ((uint8_t)arg));
}
case IOC_READ_SPI_IRQ_FLAGS:
{
uint32_t returnValue = read_spi_irq_flags(mailbox);
if(copy_to_user((void __user*)arg, &returnValue, sizeof(returnValue)) != 0 ) {
return(-EFAULT);
}
}
case IOC_SET_SPI_IRQ_MASK:
{
set_spi_irq_mask(mailbox, ((uint8_t)arg));
}
case IOC_READ_SPI_IRQ_MASK:
{
uint32_t returnValue = read_spi_irq_mask(mailbox);
if(copy_to_user((void __user*)arg, &returnValue, sizeof(returnValue)) != 0 ) {
return(-EFAULT);
}
}
default:
/* We don't recognize this command.
*/
returnValue = -EINVAL;
}
/* Return an error code appropriate to the command */
return(returnValue);
}