From db88172eac3d336d043a113efab917720a62af55 Mon Sep 17 00:00:00 2001
From: Tobias Poganiuch <tobias.poganiuch@seco.com>
Date: Mon, 21 Aug 2023 15:19:58 +0200
Subject: [PATCH] driver:ucb1400: Added reader/poll mode
Added a new mode, that polls the touchscreen periodically instead of using
the IRQ to trigger a read.
BCS 746-001452
---
drivers/input/touchscreen/ucb1400_ts.c | 151 +++++++++++++++++--------
drivers/mfd/ucb1400_core.c | 4 +-
include/linux/ucb1400.h | 5 +
3 files changed, 111 insertions(+), 49 deletions(-)
diff --git a/drivers/input/touchscreen/ucb1400_ts.c b/drivers/input/touchscreen/ucb1400_ts.c
index d0c3b11640626..32da555741439 100644
--- a/drivers/input/touchscreen/ucb1400_ts.c
+++ b/drivers/input/touchscreen/ucb1400_ts.c
@@ -202,27 +202,13 @@ static void ucb1400_clear_pending_irq(struct ucb1400_ts *ucb)
"ucb1400: unexpected IE_STATUS = %#x\n", isr);
}
-/*
- * A restriction with interrupts exists when using the ucb1400, as
- * the codec read/write routines may sleep while waiting for codec
- * access completion and uses semaphores for access control to the
- * AC97 bus. Therefore the driver is forced to use threaded interrupt
- * handler.
- */
-static irqreturn_t ucb1400_irq(int irqnr, void *devid)
+static void ucb1400_poll_touch(struct ucb1400_ts *ucb, struct touch_data *data)
{
- struct ucb1400_ts *ucb = devid;
bool penup, discard;
- struct touch_data data = {0};
int ret;
int hys_down = SECO_INF_DOWN_HYSTERESIS;
- if (unlikely(irqnr != ucb->irq))
- return IRQ_NONE;
-
- ucb1400_clear_pending_irq(ucb);
-
/* Start with a small delay before checking pendown state */
msleep(UCB1400_TS_POLL_PERIOD);
@@ -235,14 +221,14 @@ static irqreturn_t ucb1400_irq(int irqnr, void *devid)
if (!penup) {
ucb1400_adc_enable(ucb->ac97);
- data.x = ucb1400_ts_read_xpos(ucb);
- data.y = ucb1400_ts_read_ypos(ucb);
- data.p = ucb1400_ts_read_pressure(ucb);
+ data->x = ucb1400_ts_read_xpos(ucb);
+ data->y = ucb1400_ts_read_ypos(ucb);
+ data->p = ucb1400_ts_read_pressure(ucb);
ucb1400_adc_disable(ucb->ac97);
- if ((SECO_INVALID_VALUE == data.x) ||
- (SECO_INVALID_VALUE == data.y) ||
- (SECO_INVALID_VALUE == data.p)) {
+ if ((SECO_INVALID_VALUE == data->x) ||
+ (SECO_INVALID_VALUE == data->y) ||
+ (SECO_INVALID_VALUE == data->p)) {
discard = true;
}
@@ -254,7 +240,7 @@ static irqreturn_t ucb1400_irq(int irqnr, void *devid)
* needs major rework, but this work improves touch
* performance already very much.
*/
- if (data.p < (UCB1400_FILTER_MAX_ADC_VALUE / 3))
+ if (data->p < (UCB1400_FILTER_MAX_ADC_VALUE / 3))
discard = true;
}
@@ -277,10 +263,10 @@ static irqreturn_t ucb1400_irq(int irqnr, void *devid)
ucb->filter_data.pen_up_start = jiffies_to_msecs(jiffies);
if (ucb->use_median_filter)
- seco_median_filter(&ucb->ts_idev->dev, &ucb->filter_data, &data);
+ seco_median_filter(&ucb->ts_idev->dev, &ucb->filter_data, data);
if (ucb->use_low_pass_filter)
- seco_low_pass_filter(&ucb->ts_idev->dev, &ucb->filter_data, &data);
+ seco_low_pass_filter(&ucb->ts_idev->dev, &ucb->filter_data, data);
if (hys_down) {
hys_down--;
@@ -289,7 +275,7 @@ static irqreturn_t ucb1400_irq(int irqnr, void *devid)
continue;
}
- ucb1400_ts_report_event(ucb->ts_idev, &data);
+ ucb1400_ts_report_event(ucb->ts_idev, data);
wait_event_timeout(ucb->ts_wait, ucb->stopped,
msecs_to_jiffies(UCB1400_TS_POLL_PERIOD));
@@ -304,6 +290,25 @@ static irqreturn_t ucb1400_irq(int irqnr, void *devid)
* later on.
*/
seco_init_filter(&ucb->ts_idev->dev, &ucb->filter_data);
+}
+
+/*
+ * A restriction with interrupts exists when using the ucb1400, as
+ * the codec read/write routines may sleep while waiting for codec
+ * access completion and uses semaphores for access control to the
+ * AC97 bus. Therefore the driver is forced to use threaded interrupt
+ * handler.
+ */
+static irqreturn_t ucb1400_irq(int irqnr, void *devid)
+{
+ struct ucb1400_ts *ucb = devid;
+ struct touch_data data = {0};
+
+ if (unlikely(irqnr != ucb->irq))
+ return IRQ_NONE;
+
+ ucb1400_clear_pending_irq(ucb);
+ ucb1400_poll_touch(ucb, &data);
if (!ucb->stopped) {
/* Switch back to interrupt mode. */
@@ -314,15 +319,38 @@ static irqreturn_t ucb1400_irq(int irqnr, void *devid)
return IRQ_HANDLED;
}
+static void ucb1400_ts_reader(struct work_struct *work)
+{
+ struct ucb1400_ts *ucb = container_of(work, struct ucb1400_ts, ts_reader.work);
+ struct touch_data data = {0};
+
+ ucb1400_poll_touch(ucb, &data);
+
+ if (!ucb->stopped) {
+ /* Enable pen-down detection */
+ ucb1400_ts_mode_int(ucb);
+ queue_delayed_work(ucb->ts_workq, &ucb->ts_reader,
+ UCB1400_READER_INTERVAL);
+ }
+}
+
static void ucb1400_ts_stop(struct ucb1400_ts *ucb)
{
/* Signal IRQ thread to stop polling and disable the handler. */
ucb->stopped = true;
mb();
- wake_up(&ucb->ts_wait);
- disable_irq(ucb->irq);
- ucb1400_ts_irq_disable(ucb);
+ if (ucb->irq) {
+ wake_up(&ucb->ts_wait);
+ disable_irq(ucb->irq);
+ ucb1400_ts_irq_disable(ucb);
+ } else {
+ cancel_delayed_work_sync(&ucb->ts_reader);
+ destroy_workqueue(ucb->ts_workq);
+
+ dev_dbg(&ucb->ts_idev->dev, "Disabled ts_reader");
+ }
+
ucb1400_reg_write(ucb->ac97, UCB_TS_CR, 0);
}
@@ -333,10 +361,30 @@ static void ucb1400_ts_start(struct ucb1400_ts *ucb)
ucb->stopped = false;
mb();
+ /*
+ * The ucb1400_ts_mode_int function
+ * enables the pen-down detection,
+ * which is needed for both operation
+ * modes.
+ */
ucb1400_ts_mode_int(ucb);
- ucb1400_ts_irq_enable(ucb);
- enable_irq(ucb->irq);
+ if (ucb->irq) {
+ ucb1400_ts_irq_enable(ucb);
+ enable_irq(ucb->irq);
+ } else {
+ dev_dbg(&ucb->ts_idev->dev, "Init ts_reader");
+
+ ucb->ts_workq = alloc_ordered_workqueue("kucb1400", 0);
+ if (ucb->ts_workq) {
+ INIT_DELAYED_WORK(&ucb->ts_reader, ucb1400_ts_reader);
+ queue_delayed_work(ucb->ts_workq, &ucb->ts_reader,
+ UCB1400_READER_INTERVAL);
+ } else {
+ dev_err(&ucb->ts_idev->dev,
+ "Failed to create workqueue");
+ }
+ }
}
static int ucb1400_ts_open(struct input_dev *idev)
@@ -461,24 +509,28 @@ static int ucb1400_ts_probe(struct platform_device *pdev)
input_set_abs_params(ucb->ts_idev, ABS_Y, 0, y_res, 0, 0);
input_set_abs_params(ucb->ts_idev, ABS_PRESSURE, 0, UCB1400_FILTER_MAX_ADC_VALUE, 0, 0);
- ucb1400_ts_stop(ucb);
+ if (ucb->irq) {
+ ucb1400_ts_stop(ucb);
- error = request_threaded_irq(ucb->irq, NULL, ucb1400_irq,
- IRQF_TRIGGER_RISING | IRQF_ONESHOT,
- "UCB1400", ucb);
- if (error) {
- dev_err(&pdev->dev,
- "unable to grab irq%d: %d\n", ucb->irq, error);
- goto err_free_devs;
- }
+ error = request_threaded_irq(ucb->irq, NULL, ucb1400_irq,
+ IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+ "UCB1400", ucb);
+ if (error) {
+ dev_err(&pdev->dev,
+ "unable to grab irq%d: %d\n", ucb->irq, error);
+ goto err_free_devs;
+ }
- /*
- * request_threaded_irq() also enables the IRQ. We disable it again
- * immediately to balance enable/disable calls.
- * Note: We already called ucb1400_ts_stop() just before, which has
- * taken care of IRQ disabling in the UCB1400 itself.
- */
- disable_irq(ucb->irq);
+ /*
+ * request_threaded_irq() also enables the IRQ. We disable it again
+ * immediately to balance enable/disable calls.
+ * Note: We already called ucb1400_ts_stop() just before, which has
+ * taken care of IRQ disabling in the UCB1400 itself.
+ */
+ disable_irq(ucb->irq);
+ } else {
+ dev_info(&pdev->dev, "No IRQ configured");
+ }
error = input_register_device(ucb->ts_idev);
if (error)
@@ -487,7 +539,8 @@ static int ucb1400_ts_probe(struct platform_device *pdev)
return 0;
err_free_irq:
- free_irq(ucb->irq, ucb);
+ if (ucb->irq)
+ free_irq(ucb->irq, ucb);
err_free_devs:
input_free_device(ucb->ts_idev);
err:
@@ -498,7 +551,9 @@ static int ucb1400_ts_remove(struct platform_device *pdev)
{
struct ucb1400_ts *ucb = dev_get_platdata(&pdev->dev);
- free_irq(ucb->irq, ucb);
+ if (ucb->irq)
+ free_irq(ucb->irq, ucb);
+
input_unregister_device(ucb->ts_idev);
return 0;
diff --git a/drivers/mfd/ucb1400_core.c b/drivers/mfd/ucb1400_core.c
index 0894831937fc1..a8ae575389010 100644
--- a/drivers/mfd/ucb1400_core.c
+++ b/drivers/mfd/ucb1400_core.c
@@ -135,8 +135,10 @@ static int ucb1400_core_probe(struct device *dev)
if( ucb_ts.irq < 0 && pdata != NULL && pdata->irq >= 0)
ucb_ts.irq = pdata->irq;
- if( ucb_ts.irq < 0 )
+ if( ucb_ts.irq < 0 ) {
dev_warn(dev, "Failed to get irq: %d", ucb_ts.irq);
+ ucb_ts.irq = 0;
+ }
if (of_find_property(dev->of_node, "seco,use-infinite-mode", NULL))
ucb_ts.use_infinite_mode = true;
diff --git a/include/linux/ucb1400.h b/include/linux/ucb1400.h
index 32ca9e935fb5d..71b3d60ed0f8a 100644
--- a/include/linux/ucb1400.h
+++ b/include/linux/ucb1400.h
@@ -86,6 +86,9 @@
#define UCB1400_FILTER_MAX_ADC_VALUE 0x03FF
+/* Interval ts_reader in ms */
+#define UCB1400_READER_INTERVAL 10
+
struct ucb1400_gpio {
struct gpio_chip gc;
struct snd_ac97 *ac97;
@@ -106,6 +109,8 @@ struct ucb1400_ts {
bool use_low_pass_filter;
unsigned pen_up_debounce;
struct seco_filter_data filter_data;
+ struct delayed_work ts_reader;
+ struct workqueue_struct *ts_workq;
};
struct ucb1400 {
--
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