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| author | Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@gmail.com> | 2022-01-15 01:16:43 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-01-26 15:01:48 +0300 |
| commit | ce514dadc61a53ea7a2f5bbd67d31c52654e19b8 (patch) | |
| tree | 96bc06208627e94e970a746474551b00220be9c7 /drivers/staging/pi433 | |
| parent | 39ddef5681839dc9949fd280ea65869a21fca23f (diff) | |
| download | linux-ce514dadc61a53ea7a2f5bbd67d31c52654e19b8.tar.xz | |
staging: pi433: enforce tx_cfg to be set before any message can be sent
this driver relies on exposing a char device to userspace to tx
messages. Every message can be sent using different trasmitter settings
such so the tx_cfg must be written before sending any messages.
Failing to do so will cause the message to fail silently depending on
printk/dynamic_debug settings which makes it hard to troubleshoot.
This patch add a control variable that will get initialized once tx_cfg
is set for the fd used when interacting with the char device.
Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@gmail.com>
Link: https://lore.kernel.org/r/20220114221643.GA7843@mail.google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/pi433')
| -rw-r--r-- | drivers/staging/pi433/pi433_if.c | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/drivers/staging/pi433/pi433_if.c b/drivers/staging/pi433/pi433_if.c index 523a1bca0c58..17ff51f6a9da 100644 --- a/drivers/staging/pi433/pi433_if.c +++ b/drivers/staging/pi433/pi433_if.c @@ -108,6 +108,9 @@ struct pi433_device { struct pi433_instance { struct pi433_device *device; struct pi433_tx_cfg tx_cfg; + + /* control flags */ + bool tx_cfg_initialized; }; /*-------------------------------------------------------------------------*/ @@ -824,6 +827,16 @@ pi433_write(struct file *filp, const char __user *buf, return -EMSGSIZE; /* + * check if tx_cfg has been initialized otherwise we won't be able to + * config the RF trasmitter correctly due to invalid settings + */ + if (!instance->tx_cfg_initialized) { + dev_notice_once(device->dev, + "write: failed due to unconfigured tx_cfg (see PI433_IOC_WR_TX_CFG)"); + return -EINVAL; + } + + /* * write the following sequence into fifo: * - tx_cfg * - size of message @@ -897,6 +910,7 @@ pi433_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) return -EFAULT; mutex_lock(&device->tx_fifo_lock); memcpy(&instance->tx_cfg, &tx_cfg, sizeof(struct pi433_tx_cfg)); + instance->tx_cfg_initialized = true; mutex_unlock(&device->tx_fifo_lock); break; case PI433_IOC_RD_RX_CFG: @@ -949,8 +963,6 @@ static int pi433_open(struct inode *inode, struct file *filp) /* setup instance data*/ instance->device = device; - instance->tx_cfg.bit_rate = 4711; - // TODO: fill instance->tx_cfg; /* instance data as context */ filp->private_data = instance; |