Seems reasonable.
On Sun, Jan 09, 2022 at 11:26:52AM +1300, Paulo Miguel Almeida wrote:
> meta-comments:
> - I'm not entirely sure if -EPERM is the best error code to return here,
> I'm taking suggestions
Better to just return -EINVAL.
> ---
> drivers/staging/pi433/pi433_if.c | 16 +++++++++++++++-
> 1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/staging/pi433/pi433_if.c b/drivers/staging/pi433/pi433_if.c
> index 051c9052aeeb..3e9913f4bc7d 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;
> };
>
> /*-------------------------------------------------------------------------*/
> @@ -823,6 +826,16 @@ pi433_write(struct file *filp, const char __user *buf,
> if (count > MAX_MSG_SIZE)
> 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_dbg(device->dev,
> + "write: failed due to uninitialized tx_cfg");
Use dev_notice_once() or similar. Maybe "unconfigured" instead of
uninitialized?
dev_notice_once(device->dev,
"write: failed due to unconfigured tx_cfg (see PI433_IOC_WR_TX_CFG)");
> + return -EPERM;
> + }
> +
> /*
> * write the following sequence into fifo:
> * - tx_cfg
> @@ -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:
> @@ -950,7 +964,7 @@ static int pi433_open(struct inode *inode, struct file *filp)
> /* setup instance data*/
> instance->device = device;
> instance->tx_cfg.bit_rate = 4711;
This is sort of pointless because it can't work until that gets over
written.
> - // TODO: fill instance->tx_cfg;
> + instance->tx_cfg_initialized = false;
kzalloc() will already set this to false.
regards,
dan carpenter
