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| author | Xie Xiaobo <xiaobo.xie@nxp.com> | 2017-12-12 08:12:33 (GMT) |
|---|---|---|
| committer | Xie Xiaobo <xiaobo.xie@nxp.com> | 2017-12-12 08:12:33 (GMT) |
| commit | c0246a9ec4d461ef4dd7647f94005380bb9e7f0b (patch) | |
| tree | 7588601aa6ce98f5e9fd083a1b351d9023c0b295 /drivers/hid/i2c-hid/i2c-hid.c | |
| parent | 50fd1a6d79d48a7c35890aecce5a5d6b872a461d (diff) | |
| parent | 56f4a560c6d6318b5a8e18a1b3e44909a5158d1e (diff) | |
| download | linux-c0246a9ec4d461ef4dd7647f94005380bb9e7f0b.tar.xz | |
Merge Linaro linux 4.9.62 into linux-4.9
Signed-off-by: Xiaobo Xie <xiaobo.xie@nxp.com>
Diffstat (limited to 'drivers/hid/i2c-hid/i2c-hid.c')
| -rw-r--r-- | drivers/hid/i2c-hid/i2c-hid.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c index b1bce80..865e7c2 100644 --- a/drivers/hid/i2c-hid/i2c-hid.c +++ b/drivers/hid/i2c-hid/i2c-hid.c @@ -427,6 +427,15 @@ static int i2c_hid_hwreset(struct i2c_client *client) if (ret) goto out_unlock; + /* + * The HID over I2C specification states that if a DEVICE needs time + * after the PWR_ON request, it should utilise CLOCK stretching. + * However, it has been observered that the Windows driver provides a + * 1ms sleep between the PWR_ON and RESET requests and that some devices + * rely on this. + */ + usleep_range(1000, 5000); + i2c_hid_dbg(ihid, "resetting...\n"); ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0); @@ -595,7 +604,8 @@ static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size) { /* the worst case is computed from the set_report command with a * reportID > 15 and the maximum report length */ - int args_len = sizeof(__u8) + /* optional ReportID byte */ + int args_len = sizeof(__u8) + /* ReportID */ + sizeof(__u8) + /* optional ReportID byte */ sizeof(__u16) + /* data register */ sizeof(__u16) + /* size of the report */ report_size; /* report */ |