From 47c84357d95eccd77c1320b4bca74bbec649ef3c Mon Sep 17 00:00:00 2001

From: Benjamin Tissoires <benjamin.tissoires@redhat.com>

Date: Mon, 3 Apr 2017 18:18:21 +0200

Subject: [PATCH] Input: rmi4 - remove the need for artificial IRQ in case of

 HID

The IRQ from rmi4 may interfere with the one we currently use on i2c-hid.

Given that there is already a need for an external API from rmi4 to

forward the attention data, we can, in this particular case rely on a

separate workqueue to prevent cursor jumps.

Reported-by: Cameron Gutman <aicommander@gmail.com>

Reported-by: Thorsten Leemhuis <linux@leemhuis.info>

Reported-by: Jason Ekstrand <jason@jlekstrand.net>

Tested-by: Andrew Duggan <aduggan@synaptics.com>

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

Signed-off-by: Lyude <lyude@redhat.com>

---

 drivers/hid/hid-rmi.c           |  64 ---------------------

 drivers/input/rmi4/rmi_driver.c | 122 ++++++++++++++++++++++++----------------

 include/linux/rmi.h             |   1 +

 3 files changed, 75 insertions(+), 112 deletions(-)

diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c

index 0f43c42..3f38872 100644

--- a/drivers/hid/hid-rmi.c

+++ b/drivers/hid/hid-rmi.c

@@ -316,19 +316,12 @@ static int rmi_input_event(struct hid_device *hdev, u8 *data, int size)

 {

 	struct rmi_data *hdata = hid_get_drvdata(hdev);

 	struct rmi_device *rmi_dev = hdata->xport.rmi_dev;

-	unsigned long flags;

 	if (!(test_bit(RMI_STARTED, &hdata->flags)))

 		return 0;

-	local_irq_save(flags);

-

 	rmi_set_attn_data(rmi_dev, data[1], &data[2], size - 2);

-	generic_handle_irq(hdata->rmi_irq);

-

-	local_irq_restore(flags);

-

 	return 1;

 }

@@ -568,56 +561,6 @@ static const struct rmi_transport_ops hid_rmi_ops = {

 	.reset		= rmi_hid_reset,

 };

-static void rmi_irq_teardown(void *data)

-{

-	struct rmi_data *hdata = data;

-	struct irq_domain *domain = hdata->domain;

-

-	if (!domain)

-		return;

-

-	irq_dispose_mapping(irq_find_mapping(domain, 0));

-

-	irq_domain_remove(domain);

-	hdata->domain = NULL;

-	hdata->rmi_irq = 0;

-}

-

-static int rmi_irq_map(struct irq_domain *h, unsigned int virq,

-		       irq_hw_number_t hw_irq_num)

-{

-	irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq);

-

-	return 0;

-}

-

-static const struct irq_domain_ops rmi_irq_ops = {

-	.map = rmi_irq_map,

-};

-

-static int rmi_setup_irq_domain(struct hid_device *hdev)

-{

-	struct rmi_data *hdata = hid_get_drvdata(hdev);

-	int ret;

-

-	hdata->domain = irq_domain_create_linear(hdev->dev.fwnode, 1,

-						 &rmi_irq_ops, hdata);

-	if (!hdata->domain)

-		return -ENOMEM;

-

-	ret = devm_add_action_or_reset(&hdev->dev, &rmi_irq_teardown, hdata);

-	if (ret)

-		return ret;

-

-	hdata->rmi_irq = irq_create_mapping(hdata->domain, 0);

-	if (hdata->rmi_irq <= 0) {

-		hid_err(hdev, "Can't allocate an IRQ\n");

-		return hdata->rmi_irq < 0 ? hdata->rmi_irq : -ENXIO;

-	}

-

-	return 0;

-}

-

 static int rmi_probe(struct hid_device *hdev, const struct hid_device_id *id)

 {

 	struct rmi_data *data = NULL;

@@ -689,18 +632,11 @@ static int rmi_probe(struct hid_device *hdev, const struct hid_device_id *id)

 	mutex_init(&data->page_mutex);

-	ret = rmi_setup_irq_domain(hdev);

-	if (ret) {

-		hid_err(hdev, "failed to allocate IRQ domain\n");

-		return ret;

-	}

-

 	if (data->device_flags & RMI_DEVICE_HAS_PHYS_BUTTONS)

 		rmi_hid_pdata.f30_data.disable = true;

 	data->xport.dev = hdev->dev.parent;

 	data->xport.pdata = rmi_hid_pdata;

-	data->xport.pdata.irq = data->rmi_irq;

 	data->xport.proto_name = "hid";

 	data->xport.ops = &hid_rmi_ops;

diff --git a/drivers/input/rmi4/rmi_driver.c b/drivers/input/rmi4/rmi_driver.c

index 141ea22..15b22db 100644

--- a/drivers/input/rmi4/rmi_driver.c

+++ b/drivers/input/rmi4/rmi_driver.c

@@ -209,34 +209,47 @@ void rmi_set_attn_data(struct rmi_device *rmi_dev, unsigned long irq_status,

 	attn_data.data = fifo_data;

 	kfifo_put(&drvdata->attn_fifo, attn_data);

+

+	schedule_work(&drvdata->attn_work);

 }

 EXPORT_SYMBOL_GPL(rmi_set_attn_data);

-static irqreturn_t rmi_irq_fn(int irq, void *dev_id)

+static void attn_callback(struct work_struct *work)

 {

-	struct rmi_device *rmi_dev = dev_id;

-	struct rmi_driver_data *drvdata = dev_get_drvdata(&rmi_dev->dev);

+	struct rmi_driver_data *drvdata = container_of(work,

+							struct rmi_driver_data,

+							attn_work);

 	struct rmi4_attn_data attn_data = {0};

 	int ret, count;

 	count = kfifo_get(&drvdata->attn_fifo, &attn_data);

-	if (count) {

-		*(drvdata->irq_status) = attn_data.irq_status;

-		drvdata->attn_data = attn_data;

-	}

+	if (!count)

+		return;

-	ret = rmi_process_interrupt_requests(rmi_dev);

+	*(drvdata->irq_status) = attn_data.irq_status;

+	drvdata->attn_data = attn_data;

+

+	ret = rmi_process_interrupt_requests(drvdata->rmi_dev);

 	if (ret)

-		rmi_dbg(RMI_DEBUG_CORE, &rmi_dev->dev,

+		rmi_dbg(RMI_DEBUG_CORE, &drvdata->rmi_dev->dev,

 			"Failed to process interrupt request: %d\n", ret);

-	if (count) {

-		kfree(attn_data.data);

-		attn_data.data = NULL;

-	}

+	kfree(attn_data.data);

+	attn_data.data = NULL;

 	if (!kfifo_is_empty(&drvdata->attn_fifo))

-		return rmi_irq_fn(irq, dev_id);

+		schedule_work(&drvdata->attn_work);

+}

+

+static irqreturn_t rmi_irq_fn(int irq, void *dev_id)

+{

+	struct rmi_device *rmi_dev = dev_id;

+	int ret;

+

+	ret = rmi_process_interrupt_requests(rmi_dev);

+	if (ret)

+		rmi_dbg(RMI_DEBUG_CORE, &rmi_dev->dev,

+			"Failed to process interrupt request: %d\n", ret);

 	return IRQ_HANDLED;

 }

@@ -244,7 +257,6 @@ static irqreturn_t rmi_irq_fn(int irq, void *dev_id)

 static int rmi_irq_init(struct rmi_device *rmi_dev)

 {

 	struct rmi_device_platform_data *pdata = rmi_get_platform_data(rmi_dev);

-	struct rmi_driver_data *data = dev_get_drvdata(&rmi_dev->dev);

 	int irq_flags = irq_get_trigger_type(pdata->irq);

 	int ret;

@@ -262,8 +274,6 @@ static int rmi_irq_init(struct rmi_device *rmi_dev)

 		return ret;

 	}

-	data->enabled = true;

-

 	return 0;

 }

@@ -912,23 +922,27 @@ void rmi_enable_irq(struct rmi_device *rmi_dev, bool clear_wake)

 	if (data->enabled)

 		goto out;

-	enable_irq(irq);

-	data->enabled = true;

-	if (clear_wake && device_may_wakeup(rmi_dev->xport->dev)) {

-		retval = disable_irq_wake(irq);

-		if (retval)

-			dev_warn(&rmi_dev->dev,

-				 "Failed to disable irq for wake: %d\n",

-				 retval);

-	}

+	if (irq) {

+		enable_irq(irq);

+		data->enabled = true;

+		if (clear_wake && device_may_wakeup(rmi_dev->xport->dev)) {

+			retval = disable_irq_wake(irq);

+			if (retval)

+				dev_warn(&rmi_dev->dev,

+					 "Failed to disable irq for wake: %d\n",

+					 retval);

+		}

-	/*

-	 * Call rmi_process_interrupt_requests() after enabling irq,

-	 * otherwise we may lose interrupt on edge-triggered systems.

-	 */

-	irq_flags = irq_get_trigger_type(pdata->irq);

-	if (irq_flags & IRQ_TYPE_EDGE_BOTH)

-		rmi_process_interrupt_requests(rmi_dev);

+		/*

+		 * Call rmi_process_interrupt_requests() after enabling irq,

+		 * otherwise we may lose interrupt on edge-triggered systems.

+		 */

+		irq_flags = irq_get_trigger_type(pdata->irq);

+		if (irq_flags & IRQ_TYPE_EDGE_BOTH)

+			rmi_process_interrupt_requests(rmi_dev);

+	} else {

+		data->enabled = true;

+	}

 out:

 	mutex_unlock(&data->enabled_mutex);

@@ -948,20 +962,22 @@ void rmi_disable_irq(struct rmi_device *rmi_dev, bool enable_wake)

 		goto out;

 	data->enabled = false;

-	disable_irq(irq);

-	if (enable_wake && device_may_wakeup(rmi_dev->xport->dev)) {

-		retval = enable_irq_wake(irq);

-		if (retval)

-			dev_warn(&rmi_dev->dev,

-				 "Failed to enable irq for wake: %d\n",

-				 retval);

-	}

-

-	/* make sure the fifo is clean */

-	while (!kfifo_is_empty(&data->attn_fifo)) {

-		count = kfifo_get(&data->attn_fifo, &attn_data);

-		if (count)

-			kfree(attn_data.data);

+	if (irq) {

+		disable_irq(irq);

+		if (enable_wake && device_may_wakeup(rmi_dev->xport->dev)) {

+			retval = enable_irq_wake(irq);

+			if (retval)

+				dev_warn(&rmi_dev->dev,

+					 "Failed to enable irq for wake: %d\n",

+					 retval);

+		}

+	} else {

+		/* make sure the fifo is clean */

+		while (!kfifo_is_empty(&data->attn_fifo)) {

+			count = kfifo_get(&data->attn_fifo, &attn_data);

+			if (count)

+				kfree(attn_data.data);

+		}

 	}

 out:

@@ -1000,9 +1016,12 @@ EXPORT_SYMBOL_GPL(rmi_driver_resume);

 static int rmi_driver_remove(struct device *dev)

 {

 	struct rmi_device *rmi_dev = to_rmi_device(dev);

+	struct rmi_driver_data *data = dev_get_drvdata(&rmi_dev->dev);

 	rmi_disable_irq(rmi_dev, false);

+	cancel_work_sync(&data->attn_work);

+

 	rmi_f34_remove_sysfs(rmi_dev);

 	rmi_free_function_list(rmi_dev);

@@ -1232,9 +1251,15 @@ static int rmi_driver_probe(struct device *dev)

 		}

 	}

-	retval = rmi_irq_init(rmi_dev);

-	if (retval < 0)

-		goto err_destroy_functions;

+	if (pdata->irq) {

+		retval = rmi_irq_init(rmi_dev);

+		if (retval < 0)

+			goto err_destroy_functions;

+	}

+

+	data->enabled = true;

+

+	INIT_WORK(&data->attn_work, attn_callback);

 	if (data->f01_container->dev.driver) {

 		/* Driver already bound, so enable ATTN now. */

diff --git a/include/linux/rmi.h b/include/linux/rmi.h

index 6412544..dc90178 100644

--- a/include/linux/rmi.h

+++ b/include/linux/rmi.h

@@ -364,6 +364,7 @@ struct rmi_driver_data {

 	struct rmi4_attn_data attn_data;

 	DECLARE_KFIFO(attn_fifo, struct rmi4_attn_data, 16);

+	struct work_struct attn_work;

 };

 int rmi_register_transport_device(struct rmi_transport_dev *xport);