[PATCH v2] Input: rmi4 - Use platform data instead of query, when available

From: David Heidelberg via B4 Relay

Date: Thu Aug 06 2026 - 13:24:36 EST


From: David Heidelberg <david@xxxxxxx>

Platform data may define touchscreen-x-mm and touchscreen-y-mm, but
these were quietly overridden by data provided by sensor.

Signed-off-by: David Heidelberg <david@xxxxxxx>
---
This series ensures, that when invalid value is detected or mismatch
between value defined in the device-tree and the read from the
touchscreen is observed, the user is notified and zero is ignored.
---
Changes in v2:
- Reworked to use device-tree values, when available, but still detect
when both or one is missing. (Dmitry)
- Link to v1: https://patch.msgid.link/20260731-respect-x-y-mm-v1-0-3e85a4bec745@xxxxxxx
---
drivers/input/rmi4/rmi_f12.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/input/rmi4/rmi_f12.c b/drivers/input/rmi4/rmi_f12.c
index 88c28089de993..841884d967a3d 100644
--- a/drivers/input/rmi4/rmi_f12.c
+++ b/drivers/input/rmi4/rmi_f12.c
@@ -150,47 +150,55 @@ static int rmi_f12_read_sensor_tuning(struct f12_data *f12)
"%s: Inactive Border xlo:%d xhi:%d ylo:%d yhi:%d\n",
__func__,
buf[offset], buf[offset + 1],
buf[offset + 2], buf[offset + 3]);

offset += 4;
}

+ /* When platform data are provided, we're done */
+ if (sensor->x_mm && sensor->y_mm)
+ return 0;
+
/*
* Use the Query DPM feature when the resolution query register
* exists.
*/
if (rmi_get_register_desc_item(&f12->query_reg_desc,
RMI_F12_QUERY_RESOLUTION)) {
offset = rmi_register_desc_calc_reg_offset(&f12->query_reg_desc,
RMI_F12_QUERY_RESOLUTION);
query_dpm_addr = fn->fd.query_base_addr + offset;
ret = rmi_read(fn->rmi_dev, query_dpm_addr, buf);
if (ret) {
dev_err(&fn->dev, "Failed to read DPM value: %d\n", ret);
return ret;
}
dpm_resolution = buf[0];

- sensor->x_mm = sensor->max_x / dpm_resolution;
- sensor->y_mm = sensor->max_y / dpm_resolution;
+ if (!sensor->x_mm)
+ sensor->x_mm = sensor->max_x / dpm_resolution;
+ if (!sensor->y_mm)
+ sensor->y_mm = sensor->max_y / dpm_resolution;
} else {
if (rmi_register_desc_has_subpacket(item, 3)) {
rx_receivers = buf[offset];
tx_receivers = buf[offset + 1];
offset += 2;
}

/* Skip over sensor flags */
if (rmi_register_desc_has_subpacket(item, 4))
offset += 1;

- sensor->x_mm = (pitch_x * rx_receivers) >> 12;
- sensor->y_mm = (pitch_y * tx_receivers) >> 12;
+ if (!sensor->x_mm)
+ sensor->x_mm = (pitch_x * rx_receivers) >> 12;
+ if (!sensor->y_mm)
+ sensor->y_mm = (pitch_y * tx_receivers) >> 12;
}

rmi_dbg(RMI_DEBUG_FN, &fn->dev, "%s: x_mm: %d y_mm: %d\n", __func__,
sensor->x_mm, sensor->y_mm);

return 0;
}


---
base-commit: 95d6a9ccef99117115e41e9adb271243bd5e985b
change-id: 20260731-respect-x-y-mm-f74a2970e9b7

Best regards,
--
David Heidelberg <david@xxxxxxx>