diff mbox series

[v2,02/13] HID: playstation: use DualSense MAC address as unique identifier.

Message ID 20210102223109.996781-3-roderick@gaikai.com (mailing list archive)
State Superseded
Delegated to: Jiri Kosina
Headers show
Series HID: new driver for PS5 'DualSense' controller | expand

Commit Message

Roderick Colenbrander Jan. 2, 2021, 10:30 p.m. UTC
From: Roderick Colenbrander <roderick.colenbrander@sony.com>

Use the DualSense MAC address as a unique identifier for the HID device.

Signed-off-by: Roderick Colenbrander <roderick.colenbrander@sony.com>
---
 drivers/hid/hid-playstation.c | 40 +++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

Comments

Barnabás Pőcze Jan. 7, 2021, 5:22 p.m. UTC | #1
Hi


2021. január 2., szombat 23:30 keltezéssel, Roderick Colenbrander írta:

> From: Roderick Colenbrander roderick.colenbrander@sony.com
>
> Use the DualSense MAC address as a unique identifier for the HID device.
>
> Signed-off-by: Roderick Colenbrander roderick.colenbrander@sony.com
>
> [...]
>  /* Button masks for DualSense input report. */
>  #define DS_BUTTONS0_HAT_SWITCH	GENMASK(3, 0)
>  #define DS_BUTTONS0_SQUARE	BIT(4)
> @@ -132,6 +136,7 @@  static struct input_dev *ps_allocate_input_dev(struct hid_device *hdev, const ch
>  	return input_dev;
>  }
>
> +

I think this extra empty line is not necessary here.


>  static struct input_dev *ps_gamepad_create(struct hid_device *hdev)
>  {
>  	struct input_dev *gamepad;
> @@ -162,6 +167,34 @@  static struct input_dev *ps_gamepad_create(struct hid_device *hdev)
>  	return gamepad;
>  }
>
> +static int dualsense_get_mac_address(struct dualsense *ds)
> +{
> +	uint8_t *buf;
> +	int ret = 0;
> +
> +	buf = kzalloc(DS_FEATURE_REPORT_PAIRING_INFO_SIZE, GFP_KERNEL);
> +	if (!buf)
> +		return -ENOMEM;
> +
> +	ret = hid_hw_raw_request(ds->base.hdev, DS_FEATURE_REPORT_PAIRING_INFO, buf,
> +			DS_FEATURE_REPORT_PAIRING_INFO_SIZE, HID_FEATURE_REPORT,
> +			HID_REQ_GET_REPORT);
> +	if (ret < 0)
> +		goto err_free;
> +	else if (ret != DS_FEATURE_REPORT_PAIRING_INFO_SIZE) {

As per coding style[1], please either use {} for all branches, or just drop the
`else` and maybe add a new line:

```
if (ret < 0)
  goto ...

if (ret != ...) {
  ...
}
```

> +		hid_err(ds->base.hdev, "failed to retrieve DualSense pairing info\n");

I think this message could be improved to better pinpoint the actual problem
that triggers it.


> +		ret = -EINVAL;
> +		goto err_free;
> +	}
> +
> +	/* Note MAC address is stored in little endian order. */

Maybe this comment would be better placed in `struct ps_device`?


> +	memcpy(ds->base.mac_address, &buf[1], sizeof(ds->base.mac_address));
> +
> +err_free:
> +	kfree(buf);
> +	return ret;
> +}
> [...]


[1]: https://www.kernel.org/doc/html/latest/process/coding-style.html#placing-braces-and-spaces


Regards,
Barnabás Pőcze
diff mbox series

Patch

diff --git a/drivers/hid/hid-playstation.c b/drivers/hid/hid-playstation.c
index 3d5fe9069c26..af4a635997bb 100644
--- a/drivers/hid/hid-playstation.c
+++ b/drivers/hid/hid-playstation.c
@@ -21,12 +21,16 @@ 
 /* Base class for playstation devices. */
 struct ps_device {
 	struct hid_device *hdev;
+	uint8_t mac_address[6];
 
 	int (*parse_report)(struct ps_device *dev, struct hid_report *report, u8 *data, int size);
 };
 
 #define DS_INPUT_REPORT_USB			0x01
 
+#define DS_FEATURE_REPORT_PAIRING_INFO		9
+#define DS_FEATURE_REPORT_PAIRING_INFO_SIZE	19
+
 /* Button masks for DualSense input report. */
 #define DS_BUTTONS0_HAT_SWITCH	GENMASK(3, 0)
 #define DS_BUTTONS0_SQUARE	BIT(4)
@@ -132,6 +136,7 @@  static struct input_dev *ps_allocate_input_dev(struct hid_device *hdev, const ch
 	return input_dev;
 }
 
+
 static struct input_dev *ps_gamepad_create(struct hid_device *hdev)
 {
 	struct input_dev *gamepad;
@@ -162,6 +167,34 @@  static struct input_dev *ps_gamepad_create(struct hid_device *hdev)
 	return gamepad;
 }
 
+static int dualsense_get_mac_address(struct dualsense *ds)
+{
+	uint8_t *buf;
+	int ret = 0;
+
+	buf = kzalloc(DS_FEATURE_REPORT_PAIRING_INFO_SIZE, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = hid_hw_raw_request(ds->base.hdev, DS_FEATURE_REPORT_PAIRING_INFO, buf,
+			DS_FEATURE_REPORT_PAIRING_INFO_SIZE, HID_FEATURE_REPORT,
+			HID_REQ_GET_REPORT);
+	if (ret < 0)
+		goto err_free;
+	else if (ret != DS_FEATURE_REPORT_PAIRING_INFO_SIZE) {
+		hid_err(ds->base.hdev, "failed to retrieve DualSense pairing info\n");
+		ret = -EINVAL;
+		goto err_free;
+	}
+
+	/* Note MAC address is stored in little endian order. */
+	memcpy(ds->base.mac_address, &buf[1], sizeof(ds->base.mac_address));
+
+err_free:
+	kfree(buf);
+	return ret;
+}
+
 static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *report,
 		u8 *data, int size)
 {
@@ -230,6 +263,13 @@  static struct ps_device *dualsense_create(struct hid_device *hdev)
 	ds->base.parse_report = dualsense_parse_report;
 	hid_set_drvdata(hdev, ds);
 
+	ret = dualsense_get_mac_address(ds);
+	if (ret < 0) {
+		hid_err(hdev, "Failed to get MAC address from DualSense\n");
+		return ERR_PTR(ret);
+	}
+	snprintf(hdev->uniq, sizeof(hdev->uniq), "%pMR", ds->base.mac_address);
+
 	ds->gamepad = ps_gamepad_create(hdev);
 	if (IS_ERR(ds->gamepad)) {
 		ret = PTR_ERR(ds->gamepad);