[PATCH v17 08/12] input: cyapa: add gen3 trackpad device force re-calibrate function support

From: Dudley Du
Date: Tue Dec 30 2014 - 20:18:14 EST


Add force re-calibrate function supported for gen3 trackpad device,
it can be used through sysfs calibrate interface.
TEST=test on Chromebooks.

Signed-off-by: Dudley Du <dudl@xxxxxxxxxxx>
---
drivers/input/mouse/cyapa_gen3.c | 59 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 59 insertions(+)

diff --git a/drivers/input/mouse/cyapa_gen3.c b/drivers/input/mouse/cyapa_gen3.c
index 0cb52fa..c23b644 100644
--- a/drivers/input/mouse/cyapa_gen3.c
+++ b/drivers/input/mouse/cyapa_gen3.c
@@ -765,6 +765,64 @@ static int cyapa_gen3_do_fw_update(struct cyapa *cyapa,
return 0;
}

+static ssize_t cyapa_gen3_do_calibrate(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct cyapa *cyapa = dev_get_drvdata(dev);
+ int tries;
+ int ret;
+
+ ret = cyapa_read_byte(cyapa, CYAPA_CMD_DEV_STATUS);
+ if (ret < 0) {
+ dev_err(dev, "Error reading dev status: %d\n", ret);
+ goto out;
+ }
+ if ((ret & CYAPA_DEV_NORMAL) != CYAPA_DEV_NORMAL) {
+ dev_warn(dev, "Trackpad device is busy, device state: 0x%02x\n",
+ ret);
+ ret = -EAGAIN;
+ goto out;
+ }
+
+ ret = cyapa_write_byte(cyapa, CYAPA_CMD_SOFT_RESET,
+ OP_RECALIBRATION_MASK);
+ if (ret < 0) {
+ dev_err(dev, "Failed to send calibrate command: %d\n",
+ ret);
+ goto out;
+ }
+
+ tries = 20; /* max recalibration timeout 2s. */
+ do {
+ /*
+ * For this recalibration, the max time will not exceed 2s.
+ * The average time is approximately 500 - 700 ms, and we
+ * will check the status every 100 - 200ms.
+ */
+ usleep_range(100000, 200000);
+
+ ret = cyapa_read_byte(cyapa, CYAPA_CMD_DEV_STATUS);
+ if (ret < 0) {
+ dev_err(dev, "Error reading dev status: %d\n",
+ ret);
+ goto out;
+ }
+ if ((ret & CYAPA_DEV_NORMAL) == CYAPA_DEV_NORMAL)
+ break;
+ } while (--tries);
+
+ if (tries == 0) {
+ dev_err(dev, "Failed to calibrate. Timeout.\n");
+ ret = -ETIMEDOUT;
+ goto out;
+ }
+ dev_dbg(dev, "Calibration successful.\n");
+
+out:
+ return ret < 0 ? ret : count;
+}
+
static ssize_t cyapa_gen3_show_baseline(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -1157,6 +1215,7 @@ const struct cyapa_dev_ops cyapa_gen3_ops = {
.bl_initiate = cyapa_gen3_bl_initiate,

.show_baseline = cyapa_gen3_show_baseline,
+ .calibrate_store = cyapa_gen3_do_calibrate,

.initialize = cyapa_gen3_initialize,

--
1.9.1

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