drivers/input/touchscreen/wm9712.c

Source file repositories/reference/linux-study-clean/drivers/input/touchscreen/wm9712.c

File Facts

System
Linux kernel
Corpus path
drivers/input/touchscreen/wm9712.c
Extension
.c
Size
12002 bytes
Lines
468
Domain
Driver Families
Bucket
drivers/input
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (pil) {
			dev_warn(wm->dev, "pressure measurement is not "
				 "supported in 5-wire mode\n");
			pil = 0;
		}
	}

	/* touchpanel pressure current*/
	if (pil == 2) {
		dig2 |= WM9712_PIL;
		dev_dbg(wm->dev,
			"setting pressure measurement current to 400uA.\n");
	} else if (pil)
		dev_dbg(wm->dev,
			"setting pressure measurement current to 200uA.\n");
	if (!pil)
		pressure = 0;

	/* polling mode sample settling delay */
	if (delay < 0 || delay > 15) {
		dev_dbg(wm->dev, "supplied delay out of range.\n");
		delay = 4;
	}
	dig1 &= 0xff0f;
	dig1 |= WM97XX_DELAY(delay);
	dev_dbg(wm->dev, "setting adc sample delay to %d u Secs.\n",
		delay_table[delay]);

	/* mask */
	dig2 |= ((mask & 0x3) << 6);
	if (mask) {
		u16 reg;
		/* Set GPIO4 as Mask Pin*/
		reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
		wm97xx_reg_write(wm, AC97_MISC_AFE, reg | WM97XX_GPIO_4);
		reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
		wm97xx_reg_write(wm, AC97_GPIO_CFG, reg | WM97XX_GPIO_4);
	}

	/* wait - coord mode */
	if (coord)
		dig2 |= WM9712_WAIT;

	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, dig1);
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, dig2);
}

static void wm9712_dig_enable(struct wm97xx *wm, int enable)
{
	u16 dig2 = wm->dig[2];

	if (enable) {
		wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
				 dig2 | WM97XX_PRP_DET_DIG);
		wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD); /* dummy read */
	} else
		wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2,
				 dig2 & ~WM97XX_PRP_DET_DIG);
}

static void wm9712_aux_prepare(struct wm97xx *wm)
{
	memcpy(wm->dig_save, wm->dig, sizeof(wm->dig));
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, 0);
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, WM97XX_PRP_DET_DIG);
}

static void wm9712_dig_restore(struct wm97xx *wm)
{
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER1, wm->dig_save[1]);
	wm97xx_reg_write(wm, AC97_WM97XX_DIGITISER2, wm->dig_save[2]);
}

static inline int is_pden(struct wm97xx *wm)
{
	return wm->dig[2] & WM9712_PDEN;
}

/*
 * Read a sample from the WM9712 adc in polling mode.
 */
static int wm9712_poll_sample(struct wm97xx *wm, int adcsel, int *sample)
{
	int timeout = 5 * delay;
	bool wants_pen = adcsel & WM97XX_PEN_DOWN;

	if (wants_pen && !wm->pen_probably_down) {
		u16 data = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD);
		if (!(data & WM97XX_PEN_DOWN))
			return RC_PENUP;

Annotation

Implementation Notes