iio: adc: exynos_adc: Drop touchscreen support

With last user of touchscreen via ADC (S3C24xx SoC) gone, drop the
remaining code from Samsung SoC ADC driver.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://patch.msgid.link/20250830-s3c-cleanup-adc-v2-2-4f8299343d32@linaro.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

1 files changed, 1 insertions, 195 deletions

diff --git a/drivers/iio/adc/exynos_adc.c b/drivers/iio/adc/exynos_adc.c
index 6b35ea17c72c..dd4b9921a8b5 100644
--- a/drivers/iio/adc/exynos_adc.c
+++ b/drivers/iio/adc/exynos_adc.c
@@ -19,11 +19,9 @@
 #include <linux/clk.h>
 #include <linux/completion.h>
 #include <linux/of.h>
-#include <linux/of_irq.h>
 #include <linux/regulator/consumer.h>
 #include <linux/of_platform.h>
 #include <linux/err.h>
-#include <linux/input.h>
 
 #include <linux/iio/iio.h>
 #include <linux/iio/machine.h>
@@ -35,14 +33,12 @@
 
 /* S3C/EXYNOS4412/5250 ADC_V1 registers definitions */
 #define ADC_V1_CON(x)		((x) + 0x00)
-#define ADC_V1_TSC(x)		((x) + 0x04)
 #define ADC_V1_DLY(x)		((x) + 0x08)
 #define ADC_V1_DATX(x)		((x) + 0x0C)
 #define ADC_V1_DATY(x)		((x) + 0x10)
 #define ADC_V1_UPDN(x)		((x) + 0x14)
 #define ADC_V1_INTCLR(x)	((x) + 0x18)
 #define ADC_V1_MUX(x)		((x) + 0x1c)
-#define ADC_V1_CLRINTPNDNUP(x)	((x) + 0x20)
 
 /* Future ADC_V2 registers definitions */
 #define ADC_V2_CON1(x)		((x) + 0x00)
@@ -61,17 +57,12 @@
 /* Bit definitions for S3C2410 / S3C6410 ADC */
 #define ADC_S3C2410_CON_SELMUX(x) (((x) & 7) << 3)
 
-/* touch screen always uses channel 0 */
-#define ADC_S3C2410_MUX_TS	0
-
 /* ADCTSC Register Bits */
 #define ADC_S3C2443_TSC_UD_SEN		(1u << 8)
 #define ADC_S3C2410_TSC_YM_SEN		(1u << 7)
 #define ADC_S3C2410_TSC_YP_SEN		(1u << 6)
 #define ADC_S3C2410_TSC_XM_SEN		(1u << 5)
 #define ADC_S3C2410_TSC_XP_SEN		(1u << 4)
-#define ADC_S3C2410_TSC_PULL_UP_DISABLE	(1u << 3)
-#define ADC_S3C2410_TSC_AUTO_PST	(1u << 2)
 #define ADC_S3C2410_TSC_XY_PST(x)	(((x) & 0x3) << 0)
 
 #define ADC_TSC_WAIT4INT (ADC_S3C2410_TSC_YM_SEN | \
@@ -79,12 +70,6 @@
 			 ADC_S3C2410_TSC_XP_SEN | \
 			 ADC_S3C2410_TSC_XY_PST(3))
 
-#define ADC_TSC_AUTOPST	(ADC_S3C2410_TSC_YM_SEN | \
-			 ADC_S3C2410_TSC_YP_SEN | \
-			 ADC_S3C2410_TSC_XP_SEN | \
-			 ADC_S3C2410_TSC_AUTO_PST | \
-			 ADC_S3C2410_TSC_XY_PST(0))
-
 /* Bit definitions for ADC_V2 */
 #define ADC_V2_CON1_SOFT_RESET	(1u << 2)
 
@@ -116,13 +101,11 @@
 struct exynos_adc {
 	struct exynos_adc_data	*data;
 	struct device		*dev;
-	struct input_dev	*input;
 	void __iomem		*regs;
 	struct regmap		*pmu_map;
 	struct clk		*clk;
 	struct clk		*sclk;
 	unsigned int		irq;
-	unsigned int		tsirq;
 	unsigned int		delay;
 	struct regulator	*vdd;
 
@@ -131,12 +114,6 @@ struct exynos_adc {
 	u32			value;
 	unsigned int            version;
 
-	bool			ts_enabled;
-
-	bool			read_ts;
-	u32			ts_x;
-	u32			ts_y;
-
 	/*
 	 * Lock to protect from potential concurrent access to the
 	 * completion callback during a manual conversion. For this driver
@@ -507,55 +484,13 @@ static int exynos_read_raw(struct iio_dev *indio_dev,
 	return ret;
 }
 
-static int exynos_read_s3c64xx_ts(struct iio_dev *indio_dev, int *x, int *y)
-{
-	struct exynos_adc *info = iio_priv(indio_dev);
-	unsigned long time_left;
-	int ret;
-
-	mutex_lock(&info->lock);
-	info->read_ts = true;
-
-	reinit_completion(&info->completion);
-
-	writel(ADC_S3C2410_TSC_PULL_UP_DISABLE | ADC_TSC_AUTOPST,
-	       ADC_V1_TSC(info->regs));
-
-	/* Select the ts channel to be used and Trigger conversion */
-	info->data->start_conv(info, ADC_S3C2410_MUX_TS);
-
-	time_left = wait_for_completion_timeout(&info->completion,
-						EXYNOS_ADC_TIMEOUT);
-	if (time_left == 0) {
-		dev_warn(&indio_dev->dev, "Conversion timed out! Resetting\n");
-		if (info->data->init_hw)
-			info->data->init_hw(info);
-		ret = -ETIMEDOUT;
-	} else {
-		*x = info->ts_x;
-		*y = info->ts_y;
-		ret = 0;
-	}
-
-	info->read_ts = false;
-	mutex_unlock(&info->lock);
-
-	return ret;
-}
-
 static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
 {
 	struct exynos_adc *info = dev_id;
 	u32 mask = info->data->mask;
 
 	/* Read value */
-	if (info->read_ts) {
-		info->ts_x = readl(ADC_V1_DATX(info->regs));
-		info->ts_y = readl(ADC_V1_DATY(info->regs));
-		writel(ADC_TSC_WAIT4INT | ADC_S3C2443_TSC_UD_SEN, ADC_V1_TSC(info->regs));
-	} else {
-		info->value = readl(ADC_V1_DATX(info->regs)) & mask;
-	}
+	info->value = readl(ADC_V1_DATX(info->regs)) & mask;
 
 	/* clear irq */
 	if (info->data->clear_irq)
@@ -566,46 +501,6 @@ static irqreturn_t exynos_adc_isr(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-/*
- * Here we (ab)use a threaded interrupt handler to stay running
- * for as long as the touchscreen remains pressed, we report
- * a new event with the latest data and then sleep until the
- * next timer tick. This mirrors the behavior of the old
- * driver, with much less code.
- */
-static irqreturn_t exynos_ts_isr(int irq, void *dev_id)
-{
-	struct exynos_adc *info = dev_id;
-	struct iio_dev *dev = dev_get_drvdata(info->dev);
-	u32 x, y;
-	bool pressed;
-	int ret;
-
-	while (READ_ONCE(info->ts_enabled)) {
-		ret = exynos_read_s3c64xx_ts(dev, &x, &y);
-		if (ret == -ETIMEDOUT)
-			break;
-
-		pressed = x & y & ADC_DATX_PRESSED;
-		if (!pressed) {
-			input_report_key(info->input, BTN_TOUCH, 0);
-			input_sync(info->input);
-			break;
-		}
-
-		input_report_abs(info->input, ABS_X, x & ADC_DATX_MASK);
-		input_report_abs(info->input, ABS_Y, y & ADC_DATY_MASK);
-		input_report_key(info->input, BTN_TOUCH, 1);
-		input_sync(info->input);
-
-		usleep_range(1000, 1100);
-	}
-
-	writel(0, ADC_V1_CLRINTPNDNUP(info->regs));
-
-	return IRQ_HANDLED;
-}
-
 static int exynos_adc_reg_access(struct iio_dev *indio_dev,
 			      unsigned reg, unsigned writeval,
 			      unsigned *readval)
@@ -657,70 +552,12 @@ static int exynos_adc_remove_devices(struct device *dev, void *c)
 	return 0;
 }
 
-static int exynos_adc_ts_open(struct input_dev *dev)
-{
-	struct exynos_adc *info = input_get_drvdata(dev);
-
-	WRITE_ONCE(info->ts_enabled, true);
-	enable_irq(info->tsirq);
-
-	return 0;
-}
-
-static void exynos_adc_ts_close(struct input_dev *dev)
-{
-	struct exynos_adc *info = input_get_drvdata(dev);
-
-	WRITE_ONCE(info->ts_enabled, false);
-	disable_irq(info->tsirq);
-}
-
-static int exynos_adc_ts_init(struct exynos_adc *info)
-{
-	int ret;
-
-	if (info->tsirq <= 0)
-		return -ENODEV;
-
-	info->input = input_allocate_device();
-	if (!info->input)
-		return -ENOMEM;
-
-	info->input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
-	info->input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
-
-	input_set_abs_params(info->input, ABS_X, 0, 0x3FF, 0, 0);
-	input_set_abs_params(info->input, ABS_Y, 0, 0x3FF, 0, 0);
-
-	info->input->name = "S3C24xx TouchScreen";
-	info->input->id.bustype = BUS_HOST;
-	info->input->open = exynos_adc_ts_open;
-	info->input->close = exynos_adc_ts_close;
-
-	input_set_drvdata(info->input, info);
-
-	ret = input_register_device(info->input);
-	if (ret) {
-		input_free_device(info->input);
-		return ret;
-	}
-
-	ret = request_threaded_irq(info->tsirq, NULL, exynos_ts_isr,
-				   IRQF_ONESHOT | IRQF_NO_AUTOEN,
-				   "touchscreen", info);
-	if (ret)
-		input_unregister_device(info->input);
-
-	return ret;
-}
-
 static int exynos_adc_probe(struct platform_device *pdev)
 {
 	struct exynos_adc *info = NULL;
 	struct device_node *np = pdev->dev.of_node;
 	struct s3c2410_ts_mach_info *pdata = dev_get_platdata(&pdev->dev);
 	struct iio_dev *indio_dev = NULL;
-	bool has_ts = false;
 	int ret;
 	int irq;
 
@@ -751,27 +588,10 @@ static int exynos_adc_probe(struct platform_device *pdev)
 		}
 	}
 
-	/* leave out any TS related code if unreachable */
-	if (IS_REACHABLE(CONFIG_INPUT)) {
-		has_ts = of_property_read_bool(pdev->dev.of_node,
-					       "has-touchscreen") || pdata;
-	}
-
 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0)
 		return irq;
 	info->irq = irq;
-
-	if (has_ts) {
-		irq = platform_get_irq(pdev, 1);
-		if (irq == -EPROBE_DEFER)
-			return irq;
-
-		info->tsirq = irq;
-	} else {
-		info->tsirq = -1;
-	}
-
 	info->dev = &pdev->dev;
 
 	init_completion(&info->completion);
@@ -840,11 +660,6 @@ static int exynos_adc_probe(struct platform_device *pdev)
 	else
 		info->delay = 10000;
 
-	if (has_ts)
-		ret = exynos_adc_ts_init(info);
-	if (ret)
-		goto err_iio;
-
 	ret = of_platform_populate(np, exynos_adc_match, NULL, &indio_dev->dev);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "failed adding child nodes\n");
@@ -856,11 +671,6 @@ static int exynos_adc_probe(struct platform_device *pdev)
 err_of_populate:
 	device_for_each_child(&indio_dev->dev, NULL,
 				exynos_adc_remove_devices);
-	if (has_ts) {
-		input_unregister_device(info->input);
-		free_irq(info->tsirq, info);
-	}
-err_iio:
 	iio_device_unregister(indio_dev);
 err_irq:
 	free_irq(info->irq, info);
@@ -880,10 +690,6 @@ static void exynos_adc_remove(struct platform_device *pdev)
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct exynos_adc *info = iio_priv(indio_dev);
 
-	if (IS_REACHABLE(CONFIG_INPUT) && info->input) {
-		free_irq(info->tsirq, info);
-		input_unregister_device(info->input);
-	}
 	device_for_each_child(&indio_dev->dev, NULL,
 				exynos_adc_remove_devices);
 	iio_device_unregister(indio_dev);