A recent commit reordered probe so that the interrupt line is now
requested before making sure that the device exists.
This breaks machines like the Lenovo ThinkPad X13s which rely on the
HID driver to probe second-source devices and only register the variant
that is actually populated. Specifically, the interrupt line may now
already be (temporarily) claimed when doing asynchronous probing of the
touchpad:
genirq: Flags mismatch irq 191. 00082008 (hid-over-i2c) vs. 00082008 (hid-over-i2c)
i2c_hid_of 21-0015: Could not register for hid-over-i2c interrupt, irq = 191, ret = -16
i2c_hid_of: probe of 21-0015 failed with error -16
Fix this by restoring the old behaviour of first making sure the device
exists before requesting the interrupt line.
Note that something like this should probably be implemented also for
"panel followers", whose actual probe is currently effectively deferred
until the DRM panel is probed (e.g. by powering down the device after
making sure it exists and only then register it as a follower).
Fixes: 675cd877c952 ("HID: i2c-hid: Rearrange probe() to power things up later")
Cc: Douglas Anderson <[email protected]>
Cc: Maxime Ripard <[email protected]>
Signed-off-by: Johan Hovold <[email protected]>
---
Changes in v2
- initialise ihid->is_panel_follower sooner to avoid repeated property
lookups and so that it can be used consistently throughout the driver
for code that differs for "panel followers"
Link to v1: https://lore.kernel.org/lkml/[email protected]/
drivers/hid/i2c-hid/i2c-hid-core.c | 144 ++++++++++++++++-------------
1 file changed, 81 insertions(+), 63 deletions(-)
diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index 9601c0605fd9..2735cd585af0 100644
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -998,45 +998,29 @@ static int i2c_hid_core_resume(struct i2c_hid *ihid)
return hid_driver_reset_resume(hid);
}
-/**
- * __do_i2c_hid_core_initial_power_up() - First time power up of the i2c-hid device.
- * @ihid: The ihid object created during probe.
- *
- * This function is called at probe time.
- *
- * The initial power on is where we do some basic validation that the device
- * exists, where we fetch the HID descriptor, and where we create the actual
- * HID devices.
- *
- * Return: 0 or error code.
+/*
+ * Check that the device exists and parse the HID descriptor.
*/
-static int __do_i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
+static int __i2c_hid_core_probe(struct i2c_hid *ihid)
{
struct i2c_client *client = ihid->client;
struct hid_device *hid = ihid->hid;
int ret;
- ret = i2c_hid_core_power_up(ihid);
- if (ret)
- return ret;
-
/* Make sure there is something at this address */
ret = i2c_smbus_read_byte(client);
if (ret < 0) {
i2c_hid_dbg(ihid, "nothing at this address: %d\n", ret);
- ret = -ENXIO;
- goto err;
+ return -ENXIO;
}
ret = i2c_hid_fetch_hid_descriptor(ihid);
if (ret < 0) {
dev_err(&client->dev,
"Failed to fetch the HID Descriptor\n");
- goto err;
+ return ret;
}
- enable_irq(client->irq);
-
hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
hid->product = le16_to_cpu(ihid->hdesc.wProductID);
@@ -1050,17 +1034,49 @@ static int __do_i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
+ return 0;
+}
+
+static int i2c_hid_core_register_hid(struct i2c_hid *ihid)
+{
+ struct i2c_client *client = ihid->client;
+ struct hid_device *hid = ihid->hid;
+ int ret;
+
+ enable_irq(client->irq);
+
ret = hid_add_device(hid);
if (ret) {
if (ret != -ENODEV)
hid_err(client, "can't add hid device: %d\n", ret);
- goto err;
+ disable_irq(client->irq);
+ return ret;
}
return 0;
+}
+
+static int i2c_hid_core_probe_panel_follower(struct i2c_hid *ihid)
+{
+ int ret;
+
+ ret = i2c_hid_core_power_up(ihid);
+ if (ret)
+ return ret;
-err:
+ ret = __i2c_hid_core_probe(ihid);
+ if (ret)
+ goto err_power_down;
+
+ ret = i2c_hid_core_register_hid(ihid);
+ if (ret)
+ goto err_power_down;
+
+ return 0;
+
+err_power_down:
i2c_hid_core_power_down(ihid);
+
return ret;
}
@@ -1077,7 +1093,7 @@ static void ihid_core_panel_prepare_work(struct work_struct *work)
* steps.
*/
if (!hid->version)
- ret = __do_i2c_hid_core_initial_power_up(ihid);
+ ret = i2c_hid_core_probe_panel_follower(ihid);
else
ret = i2c_hid_core_resume(ihid);
@@ -1136,7 +1152,6 @@ static int i2c_hid_core_register_panel_follower(struct i2c_hid *ihid)
struct device *dev = &ihid->client->dev;
int ret;
- ihid->is_panel_follower = true;
ihid->panel_follower.funcs = &i2c_hid_core_panel_follower_funcs;
/*
@@ -1156,30 +1171,6 @@ static int i2c_hid_core_register_panel_follower(struct i2c_hid *ihid)
return 0;
}
-static int i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
-{
- /*
- * If we're a panel follower, we'll register and do our initial power
- * up when the panel turns on; otherwise we do it right away.
- */
- if (drm_is_panel_follower(&ihid->client->dev))
- return i2c_hid_core_register_panel_follower(ihid);
- else
- return __do_i2c_hid_core_initial_power_up(ihid);
-}
-
-static void i2c_hid_core_final_power_down(struct i2c_hid *ihid)
-{
- /*
- * If we're a follower, the act of unfollowing will cause us to be
- * powered down. Otherwise we need to manually do it.
- */
- if (ihid->is_panel_follower)
- drm_panel_remove_follower(&ihid->panel_follower);
- else
- i2c_hid_core_suspend(ihid, true);
-}
-
int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
u16 hid_descriptor_address, u32 quirks)
{
@@ -1211,6 +1202,7 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
ihid->ops = ops;
ihid->client = client;
ihid->wHIDDescRegister = cpu_to_le16(hid_descriptor_address);
+ ihid->is_panel_follower = drm_is_panel_follower(&client->dev);
init_waitqueue_head(&ihid->wait);
mutex_init(&ihid->reset_lock);
@@ -1224,14 +1216,10 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
return ret;
device_enable_async_suspend(&client->dev);
- ret = i2c_hid_init_irq(client);
- if (ret < 0)
- goto err_buffers_allocated;
-
hid = hid_allocate_device();
if (IS_ERR(hid)) {
ret = PTR_ERR(hid);
- goto err_irq;
+ goto err_free_buffers;
}
ihid->hid = hid;
@@ -1242,19 +1230,42 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
hid->bus = BUS_I2C;
hid->initial_quirks = quirks;
- ret = i2c_hid_core_initial_power_up(ihid);
+ /* Power on and probe unless device is a panel follower. */
+ if (!ihid->is_panel_follower) {
+ ret = i2c_hid_core_power_up(ihid);
+ if (ret < 0)
+ goto err_destroy_device;
+
+ ret = __i2c_hid_core_probe(ihid);
+ if (ret < 0)
+ goto err_power_down;
+ }
+
+ ret = i2c_hid_init_irq(client);
+ if (ret < 0)
+ goto err_power_down;
+
+ /*
+ * If we're a panel follower, we'll register when the panel turns on;
+ * otherwise we do it right away.
+ */
+ if (ihid->is_panel_follower)
+ ret = i2c_hid_core_register_panel_follower(ihid);
+ else
+ ret = i2c_hid_core_register_hid(ihid);
if (ret)
- goto err_mem_free;
+ goto err_free_irq;
return 0;
-err_mem_free:
- hid_destroy_device(hid);
-
-err_irq:
+err_free_irq:
free_irq(client->irq, ihid);
-
-err_buffers_allocated:
+err_power_down:
+ if (!ihid->is_panel_follower)
+ i2c_hid_core_power_down(ihid);
+err_destroy_device:
+ hid_destroy_device(hid);
+err_free_buffers:
i2c_hid_free_buffers(ihid);
return ret;
@@ -1266,7 +1277,14 @@ void i2c_hid_core_remove(struct i2c_client *client)
struct i2c_hid *ihid = i2c_get_clientdata(client);
struct hid_device *hid;
- i2c_hid_core_final_power_down(ihid);
+ /*
+ * If we're a follower, the act of unfollowing will cause us to be
+ * powered down. Otherwise we need to manually do it.
+ */
+ if (ihid->is_panel_follower)
+ drm_panel_remove_follower(&ihid->panel_follower);
+ else
+ i2c_hid_core_suspend(ihid, true);
hid = ihid->hid;
hid_destroy_device(hid);
--
2.41.0
On Oct 02 2023, Johan Hovold wrote:
> A recent commit reordered probe so that the interrupt line is now
> requested before making sure that the device exists.
>
> This breaks machines like the Lenovo ThinkPad X13s which rely on the
> HID driver to probe second-source devices and only register the variant
> that is actually populated. Specifically, the interrupt line may now
> already be (temporarily) claimed when doing asynchronous probing of the
> touchpad:
>
> genirq: Flags mismatch irq 191. 00082008 (hid-over-i2c) vs. 00082008 (hid-over-i2c)
> i2c_hid_of 21-0015: Could not register for hid-over-i2c interrupt, irq = 191, ret = -16
> i2c_hid_of: probe of 21-0015 failed with error -16
>
> Fix this by restoring the old behaviour of first making sure the device
> exists before requesting the interrupt line.
>
> Note that something like this should probably be implemented also for
> "panel followers", whose actual probe is currently effectively deferred
> until the DRM panel is probed (e.g. by powering down the device after
> making sure it exists and only then register it as a follower).
>
> Fixes: 675cd877c952 ("HID: i2c-hid: Rearrange probe() to power things up later")
> Cc: Douglas Anderson <[email protected]>
> Cc: Maxime Ripard <[email protected]>
> Signed-off-by: Johan Hovold <[email protected]>
> ---
>
> Changes in v2
> - initialise ihid->is_panel_follower sooner to avoid repeated property
> lookups and so that it can be used consistently throughout the driver
> for code that differs for "panel followers"
Patches looks good to me, but I can not test it unfortunately.
Doug, would you mind sending us your Ack or tested-by?
Cheers,
Benjamin
>
> Link to v1: https://lore.kernel.org/lkml/[email protected]/
>
>
> drivers/hid/i2c-hid/i2c-hid-core.c | 144 ++++++++++++++++-------------
> 1 file changed, 81 insertions(+), 63 deletions(-)
>
> diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
> index 9601c0605fd9..2735cd585af0 100644
> --- a/drivers/hid/i2c-hid/i2c-hid-core.c
> +++ b/drivers/hid/i2c-hid/i2c-hid-core.c
> @@ -998,45 +998,29 @@ static int i2c_hid_core_resume(struct i2c_hid *ihid)
> return hid_driver_reset_resume(hid);
> }
>
> -/**
> - * __do_i2c_hid_core_initial_power_up() - First time power up of the i2c-hid device.
> - * @ihid: The ihid object created during probe.
> - *
> - * This function is called at probe time.
> - *
> - * The initial power on is where we do some basic validation that the device
> - * exists, where we fetch the HID descriptor, and where we create the actual
> - * HID devices.
> - *
> - * Return: 0 or error code.
> +/*
> + * Check that the device exists and parse the HID descriptor.
> */
> -static int __do_i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
> +static int __i2c_hid_core_probe(struct i2c_hid *ihid)
> {
> struct i2c_client *client = ihid->client;
> struct hid_device *hid = ihid->hid;
> int ret;
>
> - ret = i2c_hid_core_power_up(ihid);
> - if (ret)
> - return ret;
> -
> /* Make sure there is something at this address */
> ret = i2c_smbus_read_byte(client);
> if (ret < 0) {
> i2c_hid_dbg(ihid, "nothing at this address: %d\n", ret);
> - ret = -ENXIO;
> - goto err;
> + return -ENXIO;
> }
>
> ret = i2c_hid_fetch_hid_descriptor(ihid);
> if (ret < 0) {
> dev_err(&client->dev,
> "Failed to fetch the HID Descriptor\n");
> - goto err;
> + return ret;
> }
>
> - enable_irq(client->irq);
> -
> hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
> hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
> hid->product = le16_to_cpu(ihid->hdesc.wProductID);
> @@ -1050,17 +1034,49 @@ static int __do_i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
>
> ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
>
> + return 0;
> +}
> +
> +static int i2c_hid_core_register_hid(struct i2c_hid *ihid)
> +{
> + struct i2c_client *client = ihid->client;
> + struct hid_device *hid = ihid->hid;
> + int ret;
> +
> + enable_irq(client->irq);
> +
> ret = hid_add_device(hid);
> if (ret) {
> if (ret != -ENODEV)
> hid_err(client, "can't add hid device: %d\n", ret);
> - goto err;
> + disable_irq(client->irq);
> + return ret;
> }
>
> return 0;
> +}
> +
> +static int i2c_hid_core_probe_panel_follower(struct i2c_hid *ihid)
> +{
> + int ret;
> +
> + ret = i2c_hid_core_power_up(ihid);
> + if (ret)
> + return ret;
>
> -err:
> + ret = __i2c_hid_core_probe(ihid);
> + if (ret)
> + goto err_power_down;
> +
> + ret = i2c_hid_core_register_hid(ihid);
> + if (ret)
> + goto err_power_down;
> +
> + return 0;
> +
> +err_power_down:
> i2c_hid_core_power_down(ihid);
> +
> return ret;
> }
>
> @@ -1077,7 +1093,7 @@ static void ihid_core_panel_prepare_work(struct work_struct *work)
> * steps.
> */
> if (!hid->version)
> - ret = __do_i2c_hid_core_initial_power_up(ihid);
> + ret = i2c_hid_core_probe_panel_follower(ihid);
> else
> ret = i2c_hid_core_resume(ihid);
>
> @@ -1136,7 +1152,6 @@ static int i2c_hid_core_register_panel_follower(struct i2c_hid *ihid)
> struct device *dev = &ihid->client->dev;
> int ret;
>
> - ihid->is_panel_follower = true;
> ihid->panel_follower.funcs = &i2c_hid_core_panel_follower_funcs;
>
> /*
> @@ -1156,30 +1171,6 @@ static int i2c_hid_core_register_panel_follower(struct i2c_hid *ihid)
> return 0;
> }
>
> -static int i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
> -{
> - /*
> - * If we're a panel follower, we'll register and do our initial power
> - * up when the panel turns on; otherwise we do it right away.
> - */
> - if (drm_is_panel_follower(&ihid->client->dev))
> - return i2c_hid_core_register_panel_follower(ihid);
> - else
> - return __do_i2c_hid_core_initial_power_up(ihid);
> -}
> -
> -static void i2c_hid_core_final_power_down(struct i2c_hid *ihid)
> -{
> - /*
> - * If we're a follower, the act of unfollowing will cause us to be
> - * powered down. Otherwise we need to manually do it.
> - */
> - if (ihid->is_panel_follower)
> - drm_panel_remove_follower(&ihid->panel_follower);
> - else
> - i2c_hid_core_suspend(ihid, true);
> -}
> -
> int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
> u16 hid_descriptor_address, u32 quirks)
> {
> @@ -1211,6 +1202,7 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
> ihid->ops = ops;
> ihid->client = client;
> ihid->wHIDDescRegister = cpu_to_le16(hid_descriptor_address);
> + ihid->is_panel_follower = drm_is_panel_follower(&client->dev);
>
> init_waitqueue_head(&ihid->wait);
> mutex_init(&ihid->reset_lock);
> @@ -1224,14 +1216,10 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
> return ret;
> device_enable_async_suspend(&client->dev);
>
> - ret = i2c_hid_init_irq(client);
> - if (ret < 0)
> - goto err_buffers_allocated;
> -
> hid = hid_allocate_device();
> if (IS_ERR(hid)) {
> ret = PTR_ERR(hid);
> - goto err_irq;
> + goto err_free_buffers;
> }
>
> ihid->hid = hid;
> @@ -1242,19 +1230,42 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
> hid->bus = BUS_I2C;
> hid->initial_quirks = quirks;
>
> - ret = i2c_hid_core_initial_power_up(ihid);
> + /* Power on and probe unless device is a panel follower. */
> + if (!ihid->is_panel_follower) {
> + ret = i2c_hid_core_power_up(ihid);
> + if (ret < 0)
> + goto err_destroy_device;
> +
> + ret = __i2c_hid_core_probe(ihid);
> + if (ret < 0)
> + goto err_power_down;
> + }
> +
> + ret = i2c_hid_init_irq(client);
> + if (ret < 0)
> + goto err_power_down;
> +
> + /*
> + * If we're a panel follower, we'll register when the panel turns on;
> + * otherwise we do it right away.
> + */
> + if (ihid->is_panel_follower)
> + ret = i2c_hid_core_register_panel_follower(ihid);
> + else
> + ret = i2c_hid_core_register_hid(ihid);
> if (ret)
> - goto err_mem_free;
> + goto err_free_irq;
>
> return 0;
>
> -err_mem_free:
> - hid_destroy_device(hid);
> -
> -err_irq:
> +err_free_irq:
> free_irq(client->irq, ihid);
> -
> -err_buffers_allocated:
> +err_power_down:
> + if (!ihid->is_panel_follower)
> + i2c_hid_core_power_down(ihid);
> +err_destroy_device:
> + hid_destroy_device(hid);
> +err_free_buffers:
> i2c_hid_free_buffers(ihid);
>
> return ret;
> @@ -1266,7 +1277,14 @@ void i2c_hid_core_remove(struct i2c_client *client)
> struct i2c_hid *ihid = i2c_get_clientdata(client);
> struct hid_device *hid;
>
> - i2c_hid_core_final_power_down(ihid);
> + /*
> + * If we're a follower, the act of unfollowing will cause us to be
> + * powered down. Otherwise we need to manually do it.
> + */
> + if (ihid->is_panel_follower)
> + drm_panel_remove_follower(&ihid->panel_follower);
> + else
> + i2c_hid_core_suspend(ihid, true);
>
> hid = ihid->hid;
> hid_destroy_device(hid);
> --
> 2.41.0
>
Hi,
On Thu, Oct 5, 2023 at 12:10 AM Benjamin Tissoires <[email protected]> wrote:
>
> On Oct 02 2023, Johan Hovold wrote:
> > A recent commit reordered probe so that the interrupt line is now
> > requested before making sure that the device exists.
> >
> > This breaks machines like the Lenovo ThinkPad X13s which rely on the
> > HID driver to probe second-source devices and only register the variant
> > that is actually populated. Specifically, the interrupt line may now
> > already be (temporarily) claimed when doing asynchronous probing of the
> > touchpad:
> >
> > genirq: Flags mismatch irq 191. 00082008 (hid-over-i2c) vs. 00082008 (hid-over-i2c)
> > i2c_hid_of 21-0015: Could not register for hid-over-i2c interrupt, irq = 191, ret = -16
> > i2c_hid_of: probe of 21-0015 failed with error -16
> >
> > Fix this by restoring the old behaviour of first making sure the device
> > exists before requesting the interrupt line.
> >
> > Note that something like this should probably be implemented also for
> > "panel followers", whose actual probe is currently effectively deferred
> > until the DRM panel is probed (e.g. by powering down the device after
> > making sure it exists and only then register it as a follower).
> >
> > Fixes: 675cd877c952 ("HID: i2c-hid: Rearrange probe() to power things up later")
> > Cc: Douglas Anderson <[email protected]>
> > Cc: Maxime Ripard <[email protected]>
> > Signed-off-by: Johan Hovold <[email protected]>
> > ---
> >
> > Changes in v2
> > - initialise ihid->is_panel_follower sooner to avoid repeated property
> > lookups and so that it can be used consistently throughout the driver
> > for code that differs for "panel followers"
>
> Patches looks good to me, but I can not test it unfortunately.
>
> Doug, would you mind sending us your Ack or tested-by?
Sure. Patches look OK to me, so if you're good with them then I'm good
with them too.
Reviewed-by: Douglas Anderson <[email protected]>
I tested this on a board by adding a second i2c-hid device in the
device tree and confirming that things appeared to work OK. I also
tried this with a board setup to use panel-follower (but _not_ two
sources of touchscreens) and that also worked OK. Thus:
Tested-by: Douglas Anderson <[email protected]>
As expected, combining panel-follower with two sources of touchscreen
_didn't_ work because only one of them is able to acquire the
interrupt. This is fine with me as there is nobody currently doing
that. I'm still of the belief that we need a more complete solution
for that and I'll continue to work on it.
Thanks!
-Doug
> A recent commit reordered probe so that the interrupt line is now
> requested before making sure that the device exists.
>
> This breaks machines like the Lenovo ThinkPad X13s which rely on the
> HID driver to probe second-source devices and only register the variant
> that is actually populated. Specifically, the interrupt line may now
> already be (temporarily) claimed when doing asynchronous probing of the
> touchpad:
>
> genirq: Flags mismatch irq 191. 00082008 (hid-over-i2c) vs. 00082008 (hid-over-i2c)
> i2c_hid_of 21-0015: Could not register for hid-over-i2c interrupt, irq = 191, ret = -16
> i2c_hid_of: probe of 21-0015 failed with error -16
>
> Fix this by restoring the old behaviour of first making sure the device
> exists before requesting the interrupt line.
>
> Note that something like this should probably be implemented also for
> "panel followers", whose actual probe is currently effectively deferred
> until the DRM panel is probed (e.g. by powering down the device after
> making sure it exists and only then register it as a follower).
>
> Fixes: 675cd877c952 ("HID: i2c-hid: Rearrange probe() to power things up later")
> Cc: Douglas Anderson <[email protected]>
> Cc: Maxime Ripard <[email protected]>
> Signed-off-by: Johan Hovold <[email protected]>
Tested-by: Dennis Gilmore <[email protected]>
> ---
>
> Changes in v2
> - initialise ihid->is_panel_follower sooner to avoid repeated property
> lookups and so that it can be used consistently throughout the driver
> for code that differs for "panel followers"
>
> Link to v1: https://lore.kernel.org/lkml/[email protected]/
>
>
> drivers/hid/i2c-hid/i2c-hid-core.c | 144 ++++++++++++++++-------------
> 1 file changed, 81 insertions(+), 63 deletions(-)
>
> diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
> index 9601c0605fd9..2735cd585af0 100644
> --- a/drivers/hid/i2c-hid/i2c-hid-core.c
> +++ b/drivers/hid/i2c-hid/i2c-hid-core.c
> @@ -998,45 +998,29 @@ static int i2c_hid_core_resume(struct i2c_hid *ihid)
> return hid_driver_reset_resume(hid);
> }
>
> -/**
> - * __do_i2c_hid_core_initial_power_up() - First time power up of the i2c-hid device.
> - * @ihid: The ihid object created during probe.
> - *
> - * This function is called at probe time.
> - *
> - * The initial power on is where we do some basic validation that the device
> - * exists, where we fetch the HID descriptor, and where we create the actual
> - * HID devices.
> - *
> - * Return: 0 or error code.
> +/*
> + * Check that the device exists and parse the HID descriptor.
> */
> -static int __do_i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
> +static int __i2c_hid_core_probe(struct i2c_hid *ihid)
> {
> struct i2c_client *client = ihid->client;
> struct hid_device *hid = ihid->hid;
> int ret;
>
> - ret = i2c_hid_core_power_up(ihid);
> - if (ret)
> - return ret;
> -
> /* Make sure there is something at this address */
> ret = i2c_smbus_read_byte(client);
> if (ret < 0) {
> i2c_hid_dbg(ihid, "nothing at this address: %d\n", ret);
> - ret = -ENXIO;
> - goto err;
> + return -ENXIO;
> }
>
> ret = i2c_hid_fetch_hid_descriptor(ihid);
> if (ret < 0) {
> dev_err(&client->dev,
> "Failed to fetch the HID Descriptor\n");
> - goto err;
> + return ret;
> }
>
> - enable_irq(client->irq);
> -
> hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
> hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
> hid->product = le16_to_cpu(ihid->hdesc.wProductID);
> @@ -1050,17 +1034,49 @@ static int __do_i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
>
> ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
>
> + return 0;
> +}
> +
> +static int i2c_hid_core_register_hid(struct i2c_hid *ihid)
> +{
> + struct i2c_client *client = ihid->client;
> + struct hid_device *hid = ihid->hid;
> + int ret;
> +
> + enable_irq(client->irq);
> +
> ret = hid_add_device(hid);
> if (ret) {
> if (ret != -ENODEV)
> hid_err(client, "can't add hid device: %d\n", ret);
> - goto err;
> + disable_irq(client->irq);
> + return ret;
> }
>
> return 0;
> +}
> +
> +static int i2c_hid_core_probe_panel_follower(struct i2c_hid *ihid)
> +{
> + int ret;
> +
> + ret = i2c_hid_core_power_up(ihid);
> + if (ret)
> + return ret;
>
> -err:
> + ret = __i2c_hid_core_probe(ihid);
> + if (ret)
> + goto err_power_down;
> +
> + ret = i2c_hid_core_register_hid(ihid);
> + if (ret)
> + goto err_power_down;
> +
> + return 0;
> +
> +err_power_down:
> i2c_hid_core_power_down(ihid);
> +
> return ret;
> }
>
> @@ -1077,7 +1093,7 @@ static void ihid_core_panel_prepare_work(struct work_struct *work)
> * steps.
> */
> if (!hid->version)
> - ret = __do_i2c_hid_core_initial_power_up(ihid);
> + ret = i2c_hid_core_probe_panel_follower(ihid);
> else
> ret = i2c_hid_core_resume(ihid);
>
> @@ -1136,7 +1152,6 @@ static int i2c_hid_core_register_panel_follower(struct i2c_hid *ihid)
> struct device *dev = &ihid->client->dev;
> int ret;
>
> - ihid->is_panel_follower = true;
> ihid->panel_follower.funcs = &i2c_hid_core_panel_follower_funcs;
>
> /*
> @@ -1156,30 +1171,6 @@ static int i2c_hid_core_register_panel_follower(struct i2c_hid *ihid)
> return 0;
> }
>
> -static int i2c_hid_core_initial_power_up(struct i2c_hid *ihid)
> -{
> - /*
> - * If we're a panel follower, we'll register and do our initial power
> - * up when the panel turns on; otherwise we do it right away.
> - */
> - if (drm_is_panel_follower(&ihid->client->dev))
> - return i2c_hid_core_register_panel_follower(ihid);
> - else
> - return __do_i2c_hid_core_initial_power_up(ihid);
> -}
> -
> -static void i2c_hid_core_final_power_down(struct i2c_hid *ihid)
> -{
> - /*
> - * If we're a follower, the act of unfollowing will cause us to be
> - * powered down. Otherwise we need to manually do it.
> - */
> - if (ihid->is_panel_follower)
> - drm_panel_remove_follower(&ihid->panel_follower);
> - else
> - i2c_hid_core_suspend(ihid, true);
> -}
> -
> int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
> u16 hid_descriptor_address, u32 quirks)
> {
> @@ -1211,6 +1202,7 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
> ihid->ops = ops;
> ihid->client = client;
> ihid->wHIDDescRegister = cpu_to_le16(hid_descriptor_address);
> + ihid->is_panel_follower = drm_is_panel_follower(&client->dev);
>
> init_waitqueue_head(&ihid->wait);
> mutex_init(&ihid->reset_lock);
> @@ -1224,14 +1216,10 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
> return ret;
> device_enable_async_suspend(&client->dev);
>
> - ret = i2c_hid_init_irq(client);
> - if (ret < 0)
> - goto err_buffers_allocated;
> -
> hid = hid_allocate_device();
> if (IS_ERR(hid)) {
> ret = PTR_ERR(hid);
> - goto err_irq;
> + goto err_free_buffers;
> }
>
> ihid->hid = hid;
> @@ -1242,19 +1230,42 @@ int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
> hid->bus = BUS_I2C;
> hid->initial_quirks = quirks;
>
> - ret = i2c_hid_core_initial_power_up(ihid);
> + /* Power on and probe unless device is a panel follower. */
> + if (!ihid->is_panel_follower) {
> + ret = i2c_hid_core_power_up(ihid);
> + if (ret < 0)
> + goto err_destroy_device;
> +
> + ret = __i2c_hid_core_probe(ihid);
> + if (ret < 0)
> + goto err_power_down;
> + }
> +
> + ret = i2c_hid_init_irq(client);
> + if (ret < 0)
> + goto err_power_down;
> +
> + /*
> + * If we're a panel follower, we'll register when the panel turns on;
> + * otherwise we do it right away.
> + */
> + if (ihid->is_panel_follower)
> + ret = i2c_hid_core_register_panel_follower(ihid);
> + else
> + ret = i2c_hid_core_register_hid(ihid);
> if (ret)
> - goto err_mem_free;
> + goto err_free_irq;
>
> return 0;
>
> -err_mem_free:
> - hid_destroy_device(hid);
> -
> -err_irq:
> +err_free_irq:
> free_irq(client->irq, ihid);
> -
> -err_buffers_allocated:
> +err_power_down:
> + if (!ihid->is_panel_follower)
> + i2c_hid_core_power_down(ihid);
> +err_destroy_device:
> + hid_destroy_device(hid);
> +err_free_buffers:
> i2c_hid_free_buffers(ihid);
>
> return ret;
> @@ -1266,7 +1277,14 @@ void i2c_hid_core_remove(struct i2c_client *client)
> struct i2c_hid *ihid = i2c_get_clientdata(client);
> struct hid_device *hid;
>
> - i2c_hid_core_final_power_down(ihid);
> + /*
> + * If we're a follower, the act of unfollowing will cause us to be
> + * powered down. Otherwise we need to manually do it.
> + */
> + if (ihid->is_panel_follower)
> + drm_panel_remove_follower(&ihid->panel_follower);
> + else
> + i2c_hid_core_suspend(ihid, true);
>
> hid = ihid->hid;
> hid_destroy_device(hid);
> --
> 2.41.0
>
>
>
On Mon, 02 Oct 2023 17:58:57 +0200, Johan Hovold wrote:
> A recent commit reordered probe so that the interrupt line is now
> requested before making sure that the device exists.
>
> This breaks machines like the Lenovo ThinkPad X13s which rely on the
> HID driver to probe second-source devices and only register the variant
> that is actually populated. Specifically, the interrupt line may now
> already be (temporarily) claimed when doing asynchronous probing of the
> touchpad:
>
> [...]
Applied to hid/hid.git (for-6.6/upstream-fixes), thanks!
[1/1] HID: i2c-hid: fix handling of unpopulated devices
https://git.kernel.org/hid/hid/c/9af867c05b5d
Cheers,
--
Benjamin Tissoires <[email protected]>