2021-01-27 23:59:18

by Xuezhi Zhang

[permalink] [raw]
Subject: [PATCH v9] staging: fbtft: add tearing signal detect

From: zhangxuezhi <[email protected]>

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

Signed-off-by: zhangxuezhi <[email protected]>
---
v9: change pr_* to dev_*
---
drivers/staging/fbtft/fb_st7789v.c | 132 ++++++++++++++++++++++++++++++++++++-
drivers/staging/fbtft/fbtft.h | 1 +
2 files changed, 132 insertions(+), 1 deletion(-)

diff --git a/drivers/staging/fbtft/fb_st7789v.c b/drivers/staging/fbtft/fb_st7789v.c
index 3a280cc..9aa2f36 100644
--- 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);
+ 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);
+ return rc;
+ }
+
+ disable_irq_nosync(gpiod_to_irq(par->gpio.te));
+ } else {
+ dev_info(par->info->device, "%s:%d, TE gpio not specified\n",
+ __func__, __LINE__);
+ }
/* turn off sleep mode */
write_reg(par, MIPI_DCS_EXIT_SLEEP_MODE);
mdelay(120);
@@ -137,6 +193,9 @@ static int init_display(struct fbtft_par *par)
*/
write_reg(par, PWCTRL1, 0xA4, 0xA1);

+ /*Tearing Effect Line On*/
+ if (par->gpio.te)
+ write_reg(par, 0x35, 0x00);
write_reg(par, MIPI_DCS_SET_DISPLAY_ON);

if (HSD20_IPS)
@@ -145,6 +204,76 @@ static int init_display(struct fbtft_par *par)
return 0;
}

+/*****************************************************************************
+ *
+ * int (*write_vmem)(struct fbtft_par *par);
+ *
+ *****************************************************************************/
+
+/* 16 bit pixel over 8-bit databus */
+static int st7789v_write_vmem16_bus8(struct fbtft_par *par, size_t offset, size_t len)
+{
+ u16 *vmem16;
+ __be16 *txbuf16 = par->txbuf.buf;
+ size_t remain;
+ size_t to_copy;
+ size_t tx_array_size;
+ int i;
+ int ret = 0;
+ size_t startbyte_size = 0;
+
+ fbtft_par_dbg(DEBUG_WRITE_VMEM, par, "st7789v ---%s(offset=%zu, len=%zu)\n",
+ __func__, offset, len);
+
+ remain = len / 2;
+ vmem16 = (u16 *)(par->info->screen_buffer + offset);
+
+ if (par->gpio.dc)
+ gpiod_set_value(par->gpio.dc, 1);
+
+ /* non buffered write */
+ if (!par->txbuf.buf)
+ return par->fbtftops.write(par, vmem16, len);
+
+ /* buffered write */
+ tx_array_size = par->txbuf.len / 2;
+
+ if (par->startbyte) {
+ txbuf16 = par->txbuf.buf + 1;
+ tx_array_size -= 2;
+ *(u8 *)(par->txbuf.buf) = par->startbyte | 0x2;
+ startbyte_size = 1;
+ }
+
+ while (remain) {
+ to_copy = min(tx_array_size, remain);
+ dev_dbg(par->info->device, " to_copy=%zu, remain=%zu\n",
+ to_copy, remain - to_copy);
+
+ for (i = 0; i < to_copy; i++)
+ txbuf16[i] = cpu_to_be16(vmem16[i]);
+
+ vmem16 = vmem16 + to_copy;
+ if (par->gpio.te) {
+ set_spi_panel_te_irq_status(par, true);
+ reinit_completion(&spi_panel_te);
+ ret = wait_for_completion_timeout(&spi_panel_te,
+ msecs_to_jiffies(SPI_PANEL_TE_TIMEOUT));
+ if (ret == 0)
+ dev_err(par->info->device, "wait panel TE time out\n");
+ }
+ ret = par->fbtftops.write(par, par->txbuf.buf,
+ startbyte_size + to_copy * 2);
+ if (par->gpio.te)
+ set_spi_panel_te_irq_status(par, false);
+ if (ret < 0)
+ return ret;
+ remain -= to_copy;
+ }
+
+ return ret;
+}
+
/**
* set_var() - apply LCD properties like rotation and BGR mode
*
@@ -259,6 +388,7 @@ static int blank(struct fbtft_par *par, bool on)
.gamma = HSD20_IPS_GAMMA,
.fbtftops = {
.init_display = init_display,
+ .write_vmem = st7789v_write_vmem16_bus8,
.set_var = set_var,
.set_gamma = set_gamma,
.blank = blank,
diff --git a/drivers/staging/fbtft/fbtft.h b/drivers/staging/fbtft/fbtft.h
index 76f8c09..93bac05 100644
--- a/drivers/staging/fbtft/fbtft.h
+++ b/drivers/staging/fbtft/fbtft.h
@@ -212,6 +212,7 @@ struct fbtft_par {
struct gpio_desc *wr;
struct gpio_desc *latch;
struct gpio_desc *cs;
+ struct gpio_desc *te;
struct gpio_desc *db[16];
struct gpio_desc *led[16];
struct gpio_desc *aux[16];
--
1.9.1


2021-01-27 23:59:48

by Xuezhi Zhang

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

On Wed, 27 Jan 2021 14:47:04 +0100
Geert Uytterhoeven <[email protected]> wrote:

> Hi Carlis,
>
> On Wed, Jan 27, 2021 at 2:03 PM Carlis <[email protected]> wrote:
> > From: zhangxuezhi <[email protected]>
> >
> > For st7789v ic,add tearing signal detect to avoid screen tearing
> >
> > Signed-off-by: zhangxuezhi <[email protected]>
> > ---
> > 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


2021-01-28 00:00:18

by Geert Uytterhoeven

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

Hi Carlis,

On Wed, Jan 27, 2021 at 2:03 PM Carlis <[email protected]> wrote:
> From: zhangxuezhi <[email protected]>
>
> For st7789v ic,add tearing signal detect to avoid screen tearing
>
> Signed-off-by: zhangxuezhi <[email protected]>
> ---
> 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

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

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