Re: [PATCH v12] staging: fbtft: add tearing signal detect

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Jan 28, 2021 at 08:53:55PM +0800, Carlis wrote:
> From: zhangxuezhi <zhangxuezhi1@yulong.com>
> 
> For st7789v ic,when we need continuous full screen refresh, it is best to
> wait for the TE signal arrive to avoid screen tearing
> 
> Signed-off-by: zhangxuezhi <zhangxuezhi1@yulong.com>
> ---
> v12: change dev_err to dev_err_probe and add space in comments start, and
>      delete te_mutex, change te wait logic
> v11: remove devm_gpio_put and change a dev_err to dev_info
> v10: additional notes
> v9: change pr_* to dev_*
> v8: delete a log line
> v7: return error value when request fail
> v6: add te gpio request fail deal logic
> v5: fix log print
> v4: modify some code style and change te irq set function name
> v3: modify author and signed-off-by name
> v2: add release te gpio after irq request fail
> ---
>  drivers/staging/fbtft/fb_st7789v.c | 116 +++++++++++++++++++++++++++++++++++++
>  drivers/staging/fbtft/fbtft.h      |   1 +
>  2 files changed, 117 insertions(+)
> 
> diff --git a/drivers/staging/fbtft/fb_st7789v.c b/drivers/staging/fbtft/fb_st7789v.c
> index 3a280cc..f08e9da 100644
> --- a/drivers/staging/fbtft/fb_st7789v.c
> +++ b/drivers/staging/fbtft/fb_st7789v.c
> @@ -9,7 +9,11 @@
>  #include <linux/delay.h>
>  #include <linux/init.h>
>  #include <linux/kernel.h>
> +#include <linux/interrupt.h>
> +#include <linux/completion.h>
>  #include <linux/module.h>
> +#include <linux/gpio/consumer.h>
> +
>  #include <video/mipi_display.h>
>  
>  #include "fbtft.h"
> @@ -66,6 +70,15 @@ enum st7789v_command {
>  #define MADCTL_MX BIT(6) /* bitmask for column address order */
>  #define MADCTL_MY BIT(7) /* bitmask for page address order */
>  
> +#define SPI_PANEL_TE_TIMEOUT	400 /* msecs */
> +static struct completion spi_panel_te;

Doesn't this structure have to be per-device?  How can it be global for
all devices in the system controlled by this driver?

thanks,

greg k-h