Re: [PATCH v9] staging: fbtft: add tearing signal detect
From: Geert Uytterhoeven <geert@linux-m68k.org>
Date: 2021-01-27 13:48:18
Also in:
dri-devel, lkml
Hi Carlis, On Wed, Jan 27, 2021 at 2:03 PM Carlis [off-list ref] wrote:
From: zhangxuezhi <redacted> For st7789v ic,add tearing signal detect to avoid screen tearing Signed-off-by: zhangxuezhi <redacted> --- v9: change pr_* to dev_*
Thanks for the update!
quoted hunk ↗ jump to hunk
--- 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
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds