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| author | Michael Zaidman <michael.zaidman@gmail.com> | 2022-11-05 23:11:48 +0200 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2022-11-11 11:09:36 +0100 |
| commit | 4b3da6853a619a952e8caf2e8393264dd42ffa27 (patch) | |
| tree | 7292ac52808cd83a06c78dd4fba6e4678ea79587 /drivers | |
| parent | 728b117e7862b1eb05c3aad3b2f087b26453d56a (diff) | |
| download | linux-stable-4b3da6853a619a952e8caf2e8393264dd42ffa27.tar.gz linux-stable-4b3da6853a619a952e8caf2e8393264dd42ffa27.tar.bz2 linux-stable-4b3da6853a619a952e8caf2e8393264dd42ffa27.zip | |
HID: ft260: wake up device from power saving mode
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>
Diffstat (limited to 'drivers')
| -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 40fae81386e3..ac133980dfe9 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)) { |