2021-05-19 11:12:54

by Johnny Chuang

Subject: [PATCH v2] 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.

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

Signed-off-by: Johnny Chuang <[email protected]>
---
Change in v2:
- Modify Optimized tag to Fixed tag
- Modify comment for i2c_hid_quirks
---
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..f4ee690 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 },
+ /*
+ * Elan devices don't need delay after I2C_HID_PWR_ON
+ */
+ { 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 18:29:28

by Harry Cutts

Subject: Re: [PATCH v2] HID: i2c-hid: Add I2C_HID_QUIRK_NO_DELAY_AFTER_PWR_ON to optimize timing

On Mon, 17 May 2021 at 18:37, 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.
>
> Fixed: eef4016243e9("HID: i2c-hid: Always sleep 60ms after I2C_HID_PWR_ON commands")
>
> Signed-off-by: Johnny Chuang <[email protected]>

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

> ---
> Change in v2:
> - Modify Optimized tag to Fixed tag
> - Modify comment for i2c_hid_quirks
> ---
> 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..f4ee690 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 },
> + /*
> + * Elan devices don't need delay after I2C_HID_PWR_ON
> + */
> + { 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
>