diff options
Diffstat (limited to 'drivers/mailbox/mailbox-test.c')
| -rw-r--r-- | drivers/mailbox/mailbox-test.c | 92 |
1 files changed, 82 insertions, 10 deletions
diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c index 9ca96e9db6bf..9c79f8019d2a 100644 --- a/drivers/mailbox/mailbox-test.c +++ b/drivers/mailbox/mailbox-test.c @@ -11,12 +11,14 @@ #include <linux/debugfs.h> #include <linux/err.h> +#include <linux/fs.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/mailbox_client.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> +#include <linux/poll.h> #include <linux/slab.h> #include <linux/uaccess.h> @@ -39,6 +41,8 @@ struct mbox_test_device { char *signal; char *message; spinlock_t lock; + wait_queue_head_t waitq; + struct fasync_struct *async_queue; }; static ssize_t mbox_test_signal_write(struct file *filp, @@ -81,6 +85,13 @@ static const struct file_operations mbox_test_signal_ops = { .llseek = generic_file_llseek, }; +static int mbox_test_message_fasync(int fd, struct file *filp, int on) +{ + struct mbox_test_device *tdev = filp->private_data; + + return fasync_helper(fd, filp, on, &tdev->async_queue); +} + static ssize_t mbox_test_message_write(struct file *filp, const char __user *userbuf, size_t count, loff_t *ppos) @@ -138,6 +149,20 @@ out: return ret < 0 ? ret : count; } +static bool mbox_test_message_data_ready(struct mbox_test_device *tdev) +{ + unsigned char data; + unsigned long flags; + + spin_lock_irqsave(&tdev->lock, flags); + data = tdev->rx_buffer[0]; + spin_unlock_irqrestore(&tdev->lock, flags); + + if (data != '\0') + return true; + return false; +} + static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf, size_t count, loff_t *ppos) { @@ -147,6 +172,8 @@ static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf, int l = 0; int ret; + DECLARE_WAITQUEUE(wait, current); + touser = kzalloc(MBOX_HEXDUMP_MAX_LEN + 1, GFP_KERNEL); if (!touser) return -ENOMEM; @@ -155,15 +182,29 @@ static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf, ret = snprintf(touser, 20, "<NO RX CAPABILITY>\n"); ret = simple_read_from_buffer(userbuf, count, ppos, touser, ret); - goto out; + goto kfree_err; } - if (tdev->rx_buffer[0] == '\0') { - ret = snprintf(touser, 9, "<EMPTY>\n"); - ret = simple_read_from_buffer(userbuf, count, ppos, - touser, ret); - goto out; - } + add_wait_queue(&tdev->waitq, &wait); + + do { + __set_current_state(TASK_INTERRUPTIBLE); + + if (mbox_test_message_data_ready(tdev)) + break; + + if (filp->f_flags & O_NONBLOCK) { + ret = -EAGAIN; + goto waitq_err; + } + + if (signal_pending(current)) { + ret = -ERESTARTSYS; + goto waitq_err; + } + schedule(); + + } while (1); spin_lock_irqsave(&tdev->lock, flags); @@ -185,14 +226,31 @@ static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf, spin_unlock_irqrestore(&tdev->lock, flags); ret = simple_read_from_buffer(userbuf, count, ppos, touser, MBOX_HEXDUMP_MAX_LEN); -out: +waitq_err: + __set_current_state(TASK_RUNNING); + remove_wait_queue(&tdev->waitq, &wait); +kfree_err: kfree(touser); return ret; } +static unsigned int +mbox_test_message_poll(struct file *filp, struct poll_table_struct *wait) +{ + struct mbox_test_device *tdev = filp->private_data; + + poll_wait(filp, &tdev->waitq, wait); + + if (mbox_test_message_data_ready(tdev)) + return POLLIN | POLLRDNORM; + return 0; +} + static const struct file_operations mbox_test_message_ops = { .write = mbox_test_message_write, .read = mbox_test_message_read, + .fasync = mbox_test_message_fasync, + .poll = mbox_test_message_poll, .open = simple_open, .llseek = generic_file_llseek, }; @@ -234,6 +292,10 @@ static void mbox_test_receive_message(struct mbox_client *client, void *message) memcpy(tdev->rx_buffer, message, MBOX_MAX_MSG_LEN); } spin_unlock_irqrestore(&tdev->lock, flags); + + wake_up_interruptible(&tdev->waitq); + + kill_fasync(&tdev->async_queue, SIGIO, POLL_IN); } static void mbox_test_prepare_message(struct mbox_client *client, void *message) @@ -290,6 +352,7 @@ static int mbox_test_probe(struct platform_device *pdev) { struct mbox_test_device *tdev; struct resource *res; + resource_size_t size; int ret; tdev = devm_kzalloc(&pdev->dev, sizeof(*tdev), GFP_KERNEL); @@ -298,14 +361,21 @@ static int mbox_test_probe(struct platform_device *pdev) /* It's okay for MMIO to be NULL */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + size = resource_size(res); tdev->tx_mmio = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(tdev->tx_mmio)) + if (PTR_ERR(tdev->tx_mmio) == -EBUSY) + /* if reserved area in SRAM, try just ioremap */ + tdev->tx_mmio = devm_ioremap(&pdev->dev, res->start, size); + else if (IS_ERR(tdev->tx_mmio)) tdev->tx_mmio = NULL; /* If specified, second reg entry is Rx MMIO */ res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + size = resource_size(res); tdev->rx_mmio = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(tdev->rx_mmio)) + if (PTR_ERR(tdev->rx_mmio) == -EBUSY) + tdev->rx_mmio = devm_ioremap(&pdev->dev, res->start, size); + else if (IS_ERR(tdev->rx_mmio)) tdev->rx_mmio = tdev->tx_mmio; tdev->tx_channel = mbox_test_request_channel(pdev, "tx"); @@ -334,6 +404,7 @@ static int mbox_test_probe(struct platform_device *pdev) if (ret) return ret; + init_waitqueue_head(&tdev->waitq); dev_info(&pdev->dev, "Successfully registered\n"); return 0; @@ -357,6 +428,7 @@ static const struct of_device_id mbox_test_match[] = { { .compatible = "mailbox-test" }, {}, }; +MODULE_DEVICE_TABLE(of, mbox_test_match); static struct platform_driver mbox_test_driver = { .driver = { |