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| author | Michael Zaidman <michael.zaidman@gmail.com> | 2026-08-26 13:48:05 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-09-02 14:28:34 +0200 |
| commit | 12363736643b09925575707c7d96e3dbab00f6ba (patch) | |
| tree | 6bb2ef210b4ca319d765d34f853ad9ffdfbc0deb | |
| parent | d9cd8c259b8aada86d455c13c812dc02dd957db3 (diff) | |
| download | linux-stable-12363736643b09925575707c7d96e3dbab00f6ba.tar.gz linux-stable-12363736643b09925575707c7d96e3dbab00f6ba.zip | |
HID: ft260: wake up device from power saving mode
[ Upstream commit 4b3da6853a619a952e8caf2e8393264dd42ffa27 ]
The FT260 can enter a power saving mode after being idle for longer
than 5 seconds.
When being woken up from power saving mode by an I2C write request,
a possible NACK is not correctly reported by the controller. As a
workaround, the driver will issue an I2C status report two times in
ft260_xfer_status() after the chip has been idle for more than 5s.
Co-developed-by: Enrik Berkhan <Enrik.Berkhan@inka.de>
Signed-off-by: Enrik Berkhan <Enrik.Berkhan@inka.de>
Signed-off-by: Michael Zaidman <michael.zaidman@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Stable-dep-of: bf3e39df3a39 ("HID: ft260: fix stack-use-after-return write in I2C read race")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/hid/hid-ft260.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/hid/hid-ft260.c b/drivers/hid/hid-ft260.c index 4c6c7dfdd6a7..3c4ca0016659 100644 --- a/drivers/hid/hid-ft260.c +++ b/drivers/hid/hid-ft260.c @@ -31,6 +31,8 @@ MODULE_PARM_DESC(debug, "Toggle FT260 debugging messages"); #define FT260_REPORT_MAX_LENGTH (64) #define FT260_I2C_DATA_REPORT_ID(len) (FT260_I2C_REPORT_MIN + (len - 1) / 4) +#define FT260_WAKEUP_NEEDED_AFTER_MS (4800) /* 5s minus 200ms margin */ + /* * The ft260 input report format defines 62 bytes for the data payload, but * when requested 62 bytes, the controller returns 60 and 2 in separate input @@ -237,6 +239,7 @@ struct ft260_device { struct completion wait; struct mutex lock; u8 write_buf[FT260_REPORT_MAX_LENGTH]; + unsigned long need_wakeup_at; u8 *read_buf; u16 read_idx; u16 read_len; @@ -306,6 +309,20 @@ static int ft260_xfer_status(struct ft260_device *dev) struct ft260_get_i2c_status_report report; int ret; + if (time_is_before_jiffies(dev->need_wakeup_at)) { + ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, + (u8 *)&report, sizeof(report)); + if (unlikely(ret < 0)) { + hid_err(hdev, "failed to retrieve status: %d, no wakeup\n", + ret); + } else { + dev->need_wakeup_at = jiffies + + msecs_to_jiffies(FT260_WAKEUP_NEEDED_AFTER_MS); + ft260_dbg("bus_status %#02x, wakeup\n", + report.bus_status); + } + } + ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS, (u8 *)&report, sizeof(report)); if (unlikely(ret < 0)) { |