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Message-ID: <20210126204316.00004cff@gmail.com>
Date: Tue, 26 Jan 2021 20:43:16 +0800
From: carlis <zhangxuezhi3@...il.com>
To: Dan Carpenter <dan.carpenter@...cle.com>
Cc: gregkh@...uxfoundation.org, devel@...verdev.osuosl.org,
linux-fbdev@...r.kernel.org, mh12gx2825@...il.com,
oliver.graute@...oconnector.com, linux-kernel@...r.kernel.org,
dri-devel@...ts.freedesktop.org, sbrivio@...hat.com,
colin.king@...onical.com, zhangxuezhi1@...ong.com
Subject: Re: [PATCH] fbtft: add tearing signal detect
On Tue, 26 Jan 2021 10:54:41 +0300
Dan Carpenter <dan.carpenter@...cle.com> wrote:
> On Sun, Jan 24, 2021 at 11:35:37PM +0800, Carlis wrote:
> > +static irqreturn_t spi_panel_te_handler(int irq, void *data)
> > +{
> > + complete(&spi_panel_te);
> > + return IRQ_HANDLED;
> > +}
> > +
> > +static void enable_spi_panel_te_irq(struct fbtft_par *par, bool
> > enable)
>
> It quite confused me that enable actually disables. I always feel
> like it's clearer to write these as two separate functions.
>
> > +{
> > + static int te_irq_count;
> > +
> > + if (!par->gpio.te) {
>
> This is always checked in the caller. And it's when it's NULL that
> means it's deliberate so don't print a message.
>
> > + pr_err("%s:%d,SPI panel TE GPIO not configured\n",
> > + __func__, __LINE__);
> > + return;
> > + }
> > +
> > + 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 +117,28 @@ 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 (par->gpio.te) {
>
> devm_gpiod_get_index_optional() can return NULL or error pointers. If
> it returns NULL then don't print an error message. NULL reports are
> deliberate.
>
> par->gpio.te = devm_gpiod_get_index_optional(dev, "te", 0,
> GPIOD_IN); if (IS_ERR(par->gpio.te)) {
> pr_err("%s:%d, TE gpio not specified\n", __func__,
> __LINE__); return PTR_ERR(par->gpio.te);
> }
>
> 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) {
> > + pr_err("TE request_irq failed.\n");
> > + par->gpio.te = NULL;
> > + } else {
> > +
> > disable_irq_nosync(gpiod_to_irq(par->gpio.te));
> > + pr_err("TE request_irq completion.\n");
>
> Why is this printing an error message if devm_request_irq() succeeds?
>
> > + }
> > + } else {
> > + pr_err("%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 +194,9 @@ 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 +205,76 @@ static int init_display(struct fbtft_par *par)
> > return 0;
> > }
> >
> > +/*****************************************************************************
> > + *
> > + * int (*write_vmem)(struct fbtft_par *par);
> > + *
> > +
> > *****************************************************************************/
> > + +/* 16 bit pixel over 8-bit databus */
> > +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 rc, ret = 0;
>
> Delete one of these "rc" or "rec" variables.
>
> > + 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) {
> > + enable_spi_panel_te_irq(par, true);
> > + reinit_completion(&spi_panel_te);
> > + rc =
> > wait_for_completion_timeout(&spi_panel_te,
> > +
> > msecs_to_jiffies(SPI_PANEL_TE_TIMEOUT));
> > + if (rc == 0)
> > + pr_err("wait panel TE time out\n");
> > + }
> > + ret = par->fbtftops.write(par, par->txbuf.buf,
> > +
> > startbyte_size + to_copy * 2);
>
> Line break is whacky.
>
> > + if (par->gpio.te)
> > + enable_spi_panel_te_irq(par, false);
> > + if (ret < 0)
> > + return ret;
> > + remain -= to_copy;
> > + }
> > +
> > + return ret;
>
> Shouldn't this be "return len;" or something?
>
> > +}
> > +
>
> regards,
> dan carpenter
>
OK,i will fix in patch v4
regards,
zhangxuezhi
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