Re: [PATCH v2] media: cx18: Remove unused cx18_reset_ir_gpio

[Andy Walls]

On Sun, 2024-10-13 at 00:39 +0100, linux@xxxxxxxxxxx wrote:
> From: "Dr. David Alan Gilbert" <linux@xxxxxxxxxxx>
> 
> cx18_reset_ir_gpio() has been unused in tree since 2009
> commit eefe1010a465 ("V4L/DVB (10759): cx18: Convert GPIO connected
> functions to act as v4l2_subdevices")
> 
> It has a comment saying it's exported for use by 'lirc_pvr150' but I
> don't
> see any sign of it in the lirc git, and I see it removed support
> for lirc_i2c.c 'Flavors of the Hauppage PVR-150...' in 2014.
> 

The IR Tx functionality of lirc_zilog (aka lirc_pvr150) used this when
it decided the Zilog 8051 microcontroller and firmware had wedged
itself.

If lirc_zilog is gone from staging and lirc_zilog/lirc_pvr150 is gone
from out of tree LIRC, then I guess there's no current caller of this
function.

Removing it prevents any current or future module from
bringing the IR chip out of a bad/stuck state via software.  So that's
the trade off for removing this function.

-Andy

> Remove it.
> 
> Signed-off-by: Dr. David Alan Gilbert <linux@xxxxxxxxxxx>
> ---
>  drivers/media/pci/cx18/cx18-gpio.c | 15 ---------------
>  drivers/media/pci/cx18/cx18-gpio.h |  1 -
>  2 files changed, 16 deletions(-)
> 
> diff --git a/drivers/media/pci/cx18/cx18-gpio.c
> b/drivers/media/pci/cx18/cx18-gpio.c
> index c85eb8d25837..485a6cbeb15a 100644
> --- a/drivers/media/pci/cx18/cx18-gpio.c
> +++ b/drivers/media/pci/cx18/cx18-gpio.c
> @@ -305,21 +305,6 @@ int cx18_gpio_register(struct cx18 *cx, u32 hw)
>  	return v4l2_device_register_subdev(&cx->v4l2_dev, sd);
>  }
>  
> -void cx18_reset_ir_gpio(void *data)
> -{
> -	struct cx18 *cx = to_cx18(data);
> -
> -	if (cx->card->gpio_i2c_slave_reset.ir_reset_mask == 0)
> -		return;
> -
> -	CX18_DEBUG_INFO("Resetting IR microcontroller\n");
> -
> -	v4l2_subdev_call(&cx->sd_resetctrl,
> -			 core, reset, CX18_GPIO_RESET_Z8F0811);
> -}
> -EXPORT_SYMBOL(cx18_reset_ir_gpio);
> -/* This symbol is exported for use by lirc_pvr150 for the IR-blaster 
> */
> -
>  /* Xceive tuner reset function */
>  int cx18_reset_tuner_gpio(void *dev, int component, int cmd, int
> value)
>  {
> diff --git a/drivers/media/pci/cx18/cx18-gpio.h
> b/drivers/media/pci/cx18/cx18-gpio.h
> index 0fa4c7ad2286..8d5797dea7f5 100644
> --- a/drivers/media/pci/cx18/cx18-gpio.h
> +++ b/drivers/media/pci/cx18/cx18-gpio.h
> @@ -17,5 +17,4 @@ enum cx18_gpio_reset_type {
>  	CX18_GPIO_RESET_XC2028  = 2,
>  };
>  
> -void cx18_reset_ir_gpio(void *data);
>  int cx18_reset_tuner_gpio(void *dev, int component, int cmd, int
> value);