HID: i2c-hid: Add support for ACPI GPIO interrupts

The HID over I2C specification allows to have the interrupt for a HID
device to be GPIO instead of directly connected to the IO-APIC.

Add support for this so that when the driver does not find proper interrupt
number from the I2C client structure we check if it has ACPI GpioInt()
resource listed in _CRS. If it is found we convert it to an interrupt
number and use it instead.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 50 insertions, 18 deletions

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 36053f33d6d9..ab4dd952b6ba 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -37,6 +37,7 @@
 #include <linux/mutex.h>
 #include <linux/acpi.h>
 #include <linux/of.h>
+#include <linux/gpio/consumer.h>
 
 #include <linux/i2c/i2c-hid.h>
 
@@ -144,6 +145,8 @@ struct i2c_hid {
         unsigned long           flags;          /* device flags */
 
         wait_queue_head_t       wait;           /* For waiting the interrupt */
+        struct gpio_desc        *desc;
+        int                     irq;
 
         struct i2c_hid_platform_data pdata;
 };
@@ -785,16 +788,16 @@ static int i2c_hid_init_irq(struct i2c_client *client)
         struct i2c_hid *ihid = i2c_get_clientdata(client);
         int ret;
 
-        dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
+        dev_dbg(&client->dev, "Requesting IRQ: %d\n", ihid->irq);
 
-        ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
+        ret = request_threaded_irq(ihid->irq, NULL, i2c_hid_irq,
                         IRQF_TRIGGER_LOW | IRQF_ONESHOT,
                         client->name, ihid);
         if (ret < 0) {
                 dev_warn(&client->dev,
                         "Could not register for %s interrupt, irq = %d,"
                         " ret = %d\n",
-                        client->name, client->irq, ret);
+                        client->name, ihid->irq, ret);
 
                 return ret;
         }
@@ -841,6 +844,14 @@ static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
 }
 
 #ifdef CONFIG_ACPI
+
+/* Default GPIO mapping */
+static const struct acpi_gpio_params i2c_hid_irq_gpio = { 0, 0, true };
+static const struct acpi_gpio_mapping i2c_hid_acpi_gpios[] = {
+        { "gpios", &i2c_hid_irq_gpio, 1 },
+        { },
+};
+
 static int i2c_hid_acpi_pdata(struct i2c_client *client,
                 struct i2c_hid_platform_data *pdata)
 {
@@ -866,7 +877,7 @@ static int i2c_hid_acpi_pdata(struct i2c_client *client,
         pdata->hid_descriptor_address = obj->integer.value;
         ACPI_FREE(obj);
 
-        return 0;
+        return acpi_dev_add_driver_gpios(adev, i2c_hid_acpi_gpios);
 }
 
 static const struct acpi_device_id i2c_hid_acpi_match[] = {
@@ -930,12 +941,6 @@ static int i2c_hid_probe(struct i2c_client *client,
 
         dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
 
-        if (!client->irq) {
-                dev_err(&client->dev,
-                        "HID over i2c has not been provided an Int IRQ\n");
-                return -EINVAL;
-        }
-
         ihid = kzalloc(sizeof(struct i2c_hid), GFP_KERNEL);
         if (!ihid)
                 return -ENOMEM;
@@ -955,6 +960,23 @@ static int i2c_hid_probe(struct i2c_client *client,
                 ihid->pdata = *platform_data;
         }
 
+        if (client->irq > 0) {
+                ihid->irq = client->irq;
+        } else if (ACPI_COMPANION(&client->dev)) {
+                ihid->desc = gpiod_get(&client->dev, NULL, GPIOD_IN);
+                if (IS_ERR(ihid->desc)) {
+                        dev_err(&client->dev, "Failed to get GPIO interrupt\n");
+                        return PTR_ERR(ihid->desc);
+                }
+
+                ihid->irq = gpiod_to_irq(ihid->desc);
+                if (ihid->irq < 0) {
+                        gpiod_put(ihid->desc);
+                        dev_err(&client->dev, "Failed to convert GPIO to IRQ\n");
+                        return ihid->irq;
+                }
+        }
+
         i2c_set_clientdata(client, ihid);
 
         ihid->client = client;
@@ -1017,13 +1039,16 @@ err_mem_free:
         hid_destroy_device(hid);
 
 err_irq:
-        free_irq(client->irq, ihid);
+        free_irq(ihid->irq, ihid);
 
 err_pm:
         pm_runtime_put_noidle(&client->dev);
         pm_runtime_disable(&client->dev);
 
 err:
+        if (ihid->desc)
+                gpiod_put(ihid->desc);
+
         i2c_hid_free_buffers(ihid);
         kfree(ihid);
         return ret;
@@ -1042,13 +1067,18 @@ static int i2c_hid_remove(struct i2c_client *client)
         hid = ihid->hid;
         hid_destroy_device(hid);
 
-        free_irq(client->irq, ihid);
+        free_irq(ihid->irq, ihid);
 
         if (ihid->bufsize)
                 i2c_hid_free_buffers(ihid);
 
+        if (ihid->desc)
+                gpiod_put(ihid->desc);
+
         kfree(ihid);
 
+        acpi_dev_remove_driver_gpios(ACPI_COMPANION(&client->dev));
+
         return 0;
 }
 
@@ -1060,9 +1090,9 @@ static int i2c_hid_suspend(struct device *dev)
         struct hid_device *hid = ihid->hid;
         int ret = 0;
 
-        disable_irq(client->irq);
+        disable_irq(ihid->irq);
         if (device_may_wakeup(&client->dev))
-                enable_irq_wake(client->irq);
+                enable_irq_wake(ihid->irq);
 
         if (hid->driver && hid->driver->suspend)
                 ret = hid->driver->suspend(hid, PMSG_SUSPEND);
@@ -1080,13 +1110,13 @@ static int i2c_hid_resume(struct device *dev)
         struct i2c_hid *ihid = i2c_get_clientdata(client);
         struct hid_device *hid = ihid->hid;
 
-        enable_irq(client->irq);
+        enable_irq(ihid->irq);
         ret = i2c_hid_hwreset(client);
         if (ret)
                 return ret;
 
         if (device_may_wakeup(&client->dev))
-                disable_irq_wake(client->irq);
+                disable_irq_wake(ihid->irq);
 
         if (hid->driver && hid->driver->reset_resume) {
                 ret = hid->driver->reset_resume(hid);
@@ -1101,17 +1131,19 @@ static int i2c_hid_resume(struct device *dev)
 static int i2c_hid_runtime_suspend(struct device *dev)
 {
         struct i2c_client *client = to_i2c_client(dev);
+        struct i2c_hid *ihid = i2c_get_clientdata(client);
 
         i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
-        disable_irq(client->irq);
+        disable_irq(ihid->irq);
         return 0;
 }
 
 static int i2c_hid_runtime_resume(struct device *dev)
 {
         struct i2c_client *client = to_i2c_client(dev);
+        struct i2c_hid *ihid = i2c_get_clientdata(client);
 
-        enable_irq(client->irq);
+        enable_irq(ihid->irq);
         i2c_hid_set_power(client, I2C_HID_PWR_ON);
         return 0;
 }