2021-05-19 09:20:44

by Johnny Chuang

Subject: [PATCH] HID: i2c-hid: Add I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON to optimize timing

There is a hard coding 60ms delay after I2C_HID_PWR_ON commadn.
Elan didn't need the delay, so we add a quirk to reduce boot time and resume time.

Optimized: eef4016243e9("HID: i2c-hid: Always sleep 60ms after I2C_HID_PWR_ON commands")

Signed-off-by: Johnny Chuang <[email protected]>
---
drivers/hid/i2c-hid/i2c-hid-core.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index 9993133..e7ec280 100644
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -45,6 +45,7 @@
#define I2C_HID_QUIRK_BOGUS_IRQ BIT(4)
#define I2C_HID_QUIRK_RESET_ON_RESUME BIT(5)
#define I2C_HID_QUIRK_BAD_INPUT_SIZE BIT(6)
+#define I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON BIT(8)


/* flags */
@@ -178,6 +179,11 @@ static const struct i2c_hid_quirks {
I2C_HID_QUIRK_RESET_ON_RESUME },
{ USB_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720,
I2C_HID_QUIRK_BAD_INPUT_SIZE },
+ /*
+ * Optimize boot time and resume time
+ */
+ { USB_VENDOR_ID_ELAN, HID_ANY_ID,
+ I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON },
{ 0, 0 }
};

@@ -427,7 +433,8 @@ static int i2c_hid_set_power(struct i2c_client *client, int power_state)
* PWR_ON requests. Testing has confirmed that several devices
* will not work properly without a delay after a PWR_ON request.
*/
- if (!ret && power_state == I2C_HID_PWR_ON)
+ if (!ret && power_state == I2C_HID_PWR_ON &&
+ !(ihid->quirks & I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON))
msleep(60);

return ret;
--
2.7.4

2021-05-19 09:21:07

by Harry Cutts

Subject: Re: [PATCH] HID: i2c-hid: Add I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON to optimize timing

On Mon, 17 May 2021 at 16:57, Johnny Chuang <[email protected]> wrote:
>
> There is a hard coding 60ms delay after I2C_HID_PWR_ON commadn.
> Elan didn't need the delay, so we add a quirk to reduce boot time and resume time.
>
> Optimized: eef4016243e9("HID: i2c-hid: Always sleep 60ms after I2C_HID_PWR_ON commands")

I don't think Optimized: is a valid commit tag, though I'm not sure if
it'll cause any problems.

>
> Signed-off-by: Johnny Chuang <[email protected]>
> ---
> drivers/hid/i2c-hid/i2c-hid-core.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
> index 9993133..e7ec280 100644
> --- a/drivers/hid/i2c-hid/i2c-hid-core.c
> +++ b/drivers/hid/i2c-hid/i2c-hid-core.c
> [...snip...]
> @@ -178,6 +179,11 @@ static const struct i2c_hid_quirks {
> I2C_HID_QUIRK_RESET_ON_RESUME },
> { USB_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720,
> I2C_HID_QUIRK_BAD_INPUT_SIZE },
> + /*
> + * Optimize boot time and resume time
> + */

This comment is a bit too vague to be useful; maybe state that Elan
devices don't need the delay instead, or just remove the comment.

Other than that,

Reviewed-by: Harry Cutts <[email protected]>

> + { USB_VENDOR_ID_ELAN, HID_ANY_ID,
> + I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON },
> { 0, 0 }
> };
>
> @@ -427,7 +433,8 @@ static int i2c_hid_set_power(struct i2c_client *client, int power_state)
> * PWR_ON requests. Testing has confirmed that several devices
> * will not work properly without a delay after a PWR_ON request.
> */
> - if (!ret && power_state == I2C_HID_PWR_ON)
> + if (!ret && power_state == I2C_HID_PWR_ON &&
> + !(ihid->quirks & I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON))
> msleep(60);
>
> return ret;
> --
> 2.7.4
>

2021-05-19 09:53:55

by Johnny.Chuang

Subject: RE: [PATCH] HID: i2c-hid: Add I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON to optimize timing

> On Mon, 17 May 2021 at 16:57, Johnny Chuang
> <[email protected]> wrote:
> >
> > There is a hard coding 60ms delay after I2C_HID_PWR_ON commadn.
> > Elan didn't need the delay, so we add a quirk to reduce boot time and
> resume time.
> >
> > Optimized: eef4016243e9("HID: i2c-hid: Always sleep 60ms after
> > I2C_HID_PWR_ON commands")
>
> I don't think Optimized: is a valid commit tag, though I'm not sure if it'll cause
> any problems.

I will change to Fixed tag at PATCH v2.

>
> >
> > Signed-off-by: Johnny Chuang <[email protected]>
> > ---
> > drivers/hid/i2c-hid/i2c-hid-core.c | 9 ++++++++-
> > 1 file changed, 8 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c
> > b/drivers/hid/i2c-hid/i2c-hid-core.c
> > index 9993133..e7ec280 100644
> > --- a/drivers/hid/i2c-hid/i2c-hid-core.c
> > +++ b/drivers/hid/i2c-hid/i2c-hid-core.c
> > [...snip...]
> > @@ -178,6 +179,11 @@ static const struct i2c_hid_quirks {
> > I2C_HID_QUIRK_RESET_ON_RESUME },
> > { USB_VENDOR_ID_ITE,
> I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720,
> > I2C_HID_QUIRK_BAD_INPUT_SIZE },
> > + /*
> > + * Optimize boot time and resume time
> > + */
>
> This comment is a bit too vague to be useful; maybe state that Elan devices
> don't need the delay instead, or just remove the comment.
>
> Other than that,

Okay, I will change to Elan devices don't need the delay at PATCH v2.

>
> Reviewed-by: Harry Cutts <[email protected]>
>
> > + { USB_VENDOR_ID_ELAN, HID_ANY_ID,
> > + I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON },
> > { 0, 0 }
> > };
> >
> > @@ -427,7 +433,8 @@ static int i2c_hid_set_power(struct i2c_client *client,
> int power_state)
> > * PWR_ON requests. Testing has confirmed that several devices
> > * will not work properly without a delay after a PWR_ON
> request.
> > */
> > - if (!ret && power_state == I2C_HID_PWR_ON)
> > + if (!ret && power_state == I2C_HID_PWR_ON &&
> > + !(ihid->quirks &
> I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON))
> > msleep(60);
> >
> > return ret;
> > --
> > 2.7.4
> >