Re: [PATCH] Input: elan_i2c - only increment wakeup count on touch

From: Dmitry Torokhov
Date: Tue Jun 30 2020 - 01:16:25 EST


On Mon, Jun 29, 2020 at 05:57:07PM -0700, Derek Basehore wrote:
> This moves the wakeup increment for elan devices to the touch report.
> This prevents the drivers from incorrectly reporting a wakeup when the
> resume callback resets then device, which causes an interrupt to
> occur. This also avoids error messages when these interrupts occur,
> since this behavior is expected.
>
> Signed-off-by: Derek Basehore <dbasehore@xxxxxxxxxxxx>
> ---
> drivers/input/mouse/elan_i2c_core.c | 16 +++++++++++++---
> 1 file changed, 13 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/input/mouse/elan_i2c_core.c b/drivers/input/mouse/elan_i2c_core.c
> index cdbe6b38c73c1..6ad53a75f9807 100644
> --- a/drivers/input/mouse/elan_i2c_core.c
> +++ b/drivers/input/mouse/elan_i2c_core.c
> @@ -49,6 +49,7 @@
>
> #define ETP_MAX_FINGERS 5
> #define ETP_FINGER_DATA_LEN 5
> +#define ETP_REPORT_LEN_OFFSET 0
> #define ETP_REPORT_ID 0x5D
> #define ETP_TP_REPORT_ID 0x5E
> #define ETP_REPORT_ID_OFFSET 2
> @@ -1018,6 +1019,8 @@ static void elan_report_absolute(struct elan_tp_data *data, u8 *packet)
> u8 hover_info = packet[ETP_HOVER_INFO_OFFSET];
> bool contact_valid, hover_event;
>
> + pm_wakeup_event(&data->client->dev, 0);
> +
> hover_event = hover_info & 0x40;
> for (i = 0; i < ETP_MAX_FINGERS; i++) {
> contact_valid = tp_info & (1U << (3 + i));
> @@ -1041,6 +1044,8 @@ static void elan_report_trackpoint(struct elan_tp_data *data, u8 *report)
> u8 *packet = &report[ETP_REPORT_ID_OFFSET + 1];
> int x, y;
>
> + pm_wakeup_event(&data->client->dev, 0);
> +
> if (!data->tp_input) {
> dev_warn_once(&data->client->dev,
> "received a trackpoint report while no trackpoint device has been created. Please report upstream.\n");
> @@ -1065,7 +1070,6 @@ static void elan_report_trackpoint(struct elan_tp_data *data, u8 *report)
> static irqreturn_t elan_isr(int irq, void *dev_id)
> {
> struct elan_tp_data *data = dev_id;
> - struct device *dev = &data->client->dev;
> int error;
> u8 report[ETP_MAX_REPORT_LEN];
>
> @@ -1083,7 +1087,13 @@ static irqreturn_t elan_isr(int irq, void *dev_id)
> if (error)
> goto out;
>
> - pm_wakeup_event(dev, 0);
> + /*
> + * Controllers may send a full length report on power on and reset
> + * cases. There are only meaningless bytes in these reports except for
> + * report[ETP_REPORT_LEN_OFFSET], which is 0.
> + */

Is this true for all versions of firmware? Also, should we pay attention
to the value of this field for various types of reports?

> + if (!report[ETP_REPORT_LEN_OFFSET])
> + goto out;
>
> switch (report[ETP_REPORT_ID_OFFSET]) {
> case ETP_REPORT_ID:
> @@ -1093,7 +1103,7 @@ static irqreturn_t elan_isr(int irq, void *dev_id)
> elan_report_trackpoint(data, report);
> break;
> default:
> - dev_err(dev, "invalid report id data (%x)\n",
> + dev_err(&data->client->dev, "invalid report id data (%x)\n",
> report[ETP_REPORT_ID_OFFSET]);
> }
>
> --
> 2.27.0.212.ge8ba1cc988-goog
>

Thanks.

--
Dmitry