diff options
Diffstat (limited to 'drivers/staging/pi433/pi433_if.c')
| -rw-r--r-- | drivers/staging/pi433/pi433_if.c | 39 |
1 files changed, 26 insertions, 13 deletions
diff --git a/drivers/staging/pi433/pi433_if.c b/drivers/staging/pi433/pi433_if.c index d1e0ddbc79ce..b061f77dda41 100644 --- a/drivers/staging/pi433/pi433_if.c +++ b/drivers/staging/pi433/pi433_if.c @@ -87,7 +87,7 @@ struct pi433_device { /* tx related values */ STRUCT_KFIFO_REC_1(MSG_FIFO_SIZE) tx_fifo; - struct mutex tx_fifo_lock; // TODO: check, whether necessary or obsolete + struct mutex tx_fifo_lock; /* serialize userspace writers */ struct task_struct *tx_task_struct; wait_queue_head_t tx_wait_queue; u8 free_in_fifo; @@ -589,19 +589,19 @@ pi433_tx_thread(void *data) * - size of message * - message */ - mutex_lock(&device->tx_fifo_lock); - retval = kfifo_out(&device->tx_fifo, &tx_cfg, sizeof(tx_cfg)); if (retval != sizeof(tx_cfg)) { - dev_dbg(device->dev, "reading tx_cfg from fifo failed: got %d byte(s), expected %d", retval, (unsigned int)sizeof(tx_cfg)); - mutex_unlock(&device->tx_fifo_lock); + dev_dbg(device->dev, + "reading tx_cfg from fifo failed: got %d byte(s), expected %d", + retval, (unsigned int)sizeof(tx_cfg)); continue; } retval = kfifo_out(&device->tx_fifo, &size, sizeof(size_t)); if (retval != sizeof(size_t)) { - dev_dbg(device->dev, "reading msg size from fifo failed: got %d, expected %d", retval, (unsigned int)sizeof(size_t)); - mutex_unlock(&device->tx_fifo_lock); + dev_dbg(device->dev, + "reading msg size from fifo failed: got %d, expected %d", + retval, (unsigned int)sizeof(size_t)); continue; } @@ -623,7 +623,11 @@ pi433_tx_thread(void *data) /* add length byte, if requested */ if (tx_cfg.enable_length_byte == OPTION_ON) - device->buffer[position++] = size - 1; /* according to spec length byte itself must be excluded from the length calculation */ + /* + * according to spec, length byte itself must be + * excluded from the length calculation + */ + device->buffer[position++] = size - 1; /* add adr byte, if requested */ if (tx_cfg.enable_address_byte == OPTION_ON) @@ -634,7 +638,6 @@ pi433_tx_thread(void *data) sizeof(device->buffer) - position); dev_dbg(device->dev, "read %d message byte(s) from fifo queue.", retval); - mutex_unlock(&device->tx_fifo_lock); /* if rx is active, we need to interrupt the waiting for * incoming telegrams, to be able to send something. @@ -818,7 +821,7 @@ pi433_write(struct file *filp, const char __user *buf, struct pi433_instance *instance; struct pi433_device *device; int retval; - unsigned int copied; + unsigned int required, available, copied; instance = filp->private_data; device = instance->device; @@ -833,6 +836,16 @@ pi433_write(struct file *filp, const char __user *buf, * - message */ mutex_lock(&device->tx_fifo_lock); + + required = sizeof(instance->tx_cfg) + sizeof(size_t) + count; + available = kfifo_avail(&device->tx_fifo); + if (required > available) { + dev_dbg(device->dev, "write to fifo failed: %d bytes required but %d available", + required, available); + mutex_unlock(&device->tx_fifo_lock); + return -EAGAIN; + } + retval = kfifo_in(&device->tx_fifo, &instance->tx_cfg, sizeof(instance->tx_cfg)); if (retval != sizeof(instance->tx_cfg)) @@ -855,8 +868,8 @@ pi433_write(struct file *filp, const char __user *buf, return copied; abort: - dev_dbg(device->dev, "write to fifo failed: 0x%x", retval); - kfifo_reset(&device->tx_fifo); // TODO: maybe find a solution, not to discard already stored, valid entries + dev_warn(device->dev, + "write to fifo failed, non recoverable: 0x%x", retval); mutex_unlock(&device->tx_fifo_lock); return -EAGAIN; } @@ -1042,7 +1055,7 @@ static int setup_gpio(struct pi433_device *device) /* configure irq */ device->irq_num[i] = gpiod_to_irq(device->gpiod[i]); if (device->irq_num[i] < 0) { - device->gpiod[i] = ERR_PTR(-EINVAL);//(struct gpio_desc *)device->irq_num[i]; + device->gpiod[i] = ERR_PTR(-EINVAL); return device->irq_num[i]; } retval = request_irq(device->irq_num[i], |