Re: [PATCH] HID: rmi: Make sure the HID device is opened on resume
From: Benjamin Tissoires <hidden>
Date: 2017-07-24 08:15:51
Also in:
lkml, stable
On Jul 22 2017 or thereabouts, Lyude wrote:
So it looks like that suspend/resume has actually always been broken on hid-rmi. The fact it worked was a rather silly coincidence that was relying on the HID device to already be opened upon resume. This means that so long as anything was reading the /dev/input/eventX node for for an RMI device, it would suspend and resume correctly. As well, if nothing happened to be keeping the HID device away it would shut off, then the RMI driver would get confused on resume when it stopped responding and explode.
Oh, good finding. However, given that there are few other drivers not calling hid_hw_open during their .reset_resume() callback and those drivers also are communicating with the device, I wonder if we should not have something more generic, that will call hid_hw_open/close in the transport layer directly. I do not recall having seen bugs for Wacom devices, so maybe this is something i2c-hid related, but it wouldn't hurt I guess to open/close the device before calling reset_resume. Cheers, Benjamin
quoted hunk ↗ jump to hunk
So, call hid_hw_open() in rmi_post_resume() so we make sure that the device is alive before we try talking to it. This fixes RMI device suspend/resume over HID. Signed-off-by: Lyude <lyude@redhat.com> Cc: Andrew Duggan <redacted> Cc: stable@vger.kernel.org --- drivers/hid/hid-rmi.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c index 5b40c2614599..e7d124f9a27f 100644 --- a/drivers/hid/hid-rmi.c +++ b/drivers/hid/hid-rmi.c@@ -431,22 +431,29 @@ static int rmi_post_resume(struct hid_device *hdev) { struct rmi_data *data = hid_get_drvdata(hdev); struct rmi_device *rmi_dev = data->xport.rmi_dev; - int ret; + int ret = 0; if (!(data->device_flags & RMI_DEVICE)) return 0; - ret = rmi_reset_attn_mode(hdev); + /* Make sure the HID device is ready to receive events */ + ret = hid_hw_open(hdev); if (ret) return ret; + ret = rmi_reset_attn_mode(hdev); + if (ret) + goto out; + ret = rmi_driver_resume(rmi_dev, false); if (ret) { hid_warn(hdev, "Failed to resume device: %d\n", ret); - return ret; + goto out; } - return 0; +out: + hid_hw_close(hdev); + return ret; } #endif /* CONFIG_PM */-- 2.13.3