Re: [PATCH v9] staging: fbtft: add tearing signal detect

On Wed, 27 Jan 2021 14:47:04 +0100 Geert Uytterhoeven geert@linux-m68k.org wrote:

Hi Carlis,

On Wed, Jan 27, 2021 at 2:03 PM Carlis zhangxuezhi3@gmail.com wrote:

...

From: zhangxuezhi zhangxuezhi1@yulong.com

For st7789v ic,add tearing signal detect to avoid screen tearing

Signed-off-by: zhangxuezhi zhangxuezhi1@yulong.com

v9: change pr_* to dev_*

Thanks for the update!

...

--- a/drivers/staging/fbtft/fb_st7789v.c +++ b/drivers/staging/fbtft/fb_st7789v.c @@ -9,9 +9,12 @@ #include <linux/delay.h> #include <linux/init.h> #include <linux/kernel.h> +#include <linux/mutex.h> +#include <linux/interrupt.h> +#include <linux/completion.h> #include <linux/module.h> #include <video/mipi_display.h>

+#include <linux/gpio/consumer.h> #include "fbtft.h"

#define DRVNAME "fb_st7789v" @@ -66,6 +69,32 @@ 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 +static struct mutex te_mutex;/*mutex for tearing line*/ +static struct completion spi_panel_te;

+static irqreturn_t spi_panel_te_handler(int irq, void *data) +{

•   complete(&spi_panel_te);
  

•   return IRQ_HANDLED;
  

+}

+static void set_spi_panel_te_irq_status(struct fbtft_par *par, bool enable) +{

•   static int te_irq_count;
  

•   mutex_lock(&te_mutex);
  

•   if (enable) {
  

•           if (++te_irq_count == 1)
  

•                   enable_irq(gpiod_to_irq(par->gpio.te));
  

•   } else {
  

•           if (--te_irq_count == 0)
  

•                   disable_irq(gpiod_to_irq(par->gpio.te));
  

•   }
  

•   mutex_unlock(&te_mutex);
  

+}

/**

• init_display() - initialize the display controller

@@ -82,6 +111,33 @@ enum st7789v_command { */ static int init_display(struct fbtft_par *par) {

•   int rc;
  

•   struct device *dev = par->info->device;
  

•   par->gpio.te = devm_gpiod_get_index_optional(dev, "te", 0,
  

GPIOD_IN);

•   if (IS_ERR(par->gpio.te)) {
  

•           rc = PTR_ERR(par->gpio.te);
  

•           dev_err(par->info->device, "Failed to request te
  

gpio: %d\n", rc);

This also prints an error in case of -EPROBE_DEFER. dev_err_probe()?

...

•           return rc;
  

•   }
  

•   if (par->gpio.te) {
  

•           init_completion(&spi_panel_te);
  

•           mutex_init(&te_mutex);
  

•           rc = devm_request_irq(dev,
  

•                                 gpiod_to_irq(par->gpio.te),
  

•                                spi_panel_te_handler,
  

IRQF_TRIGGER_RISING,

•                                "TE_GPIO", par);
  

•           if (rc) {
  

•                   dev_err(par->info->device, "TE request_irq
  

failed.\n");

•                   devm_gpiod_put(dev, par->gpio.te);  
  

No need to call devm_gpiod_put() here, as it's managed automatically.

Gr{oetje,eeting}s,

                    Geert

hi,i will fix in patch v11 regards zhangxuezhi1