[PATCH v2 11/12] Input: synaptics-rmi4 - smbus: on resume, try 3 times if init fails

From: Benjamin Tissoires
Date: Wed Sep 28 2016 - 04:37:20 EST


In some rare cases, we can't retrieve the SMBus version and so we fail
binding the touchpad back. Instead of leaving a touchpad dead, try again
to reinitialize it.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>

---

no changes in v2
---
drivers/input/rmi4/rmi_smbus.c | 21 ++++++++++++++++++++-
1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/input/rmi4/rmi_smbus.c b/drivers/input/rmi4/rmi_smbus.c
index 023dbd5..a8e4af6 100644
--- a/drivers/input/rmi4/rmi_smbus.c
+++ b/drivers/input/rmi4/rmi_smbus.c
@@ -265,10 +265,29 @@ static int rmi_smb_reset(struct rmi_transport_dev *xport, u16 reset_addr)
{
struct rmi_smb_xport *rmi_smb =
container_of(xport, struct rmi_smb_xport, xport);
+ struct i2c_client *client = rmi_smb->client;
+ struct rmi_device_platform_data *pdata;
+ int tries, ret;

rmi_smb_clear_state(rmi_smb);

- return rmi_smb_enable_smbus_mode(rmi_smb);
+ for (tries = 3; tries > 0; tries--) {
+ ret = rmi_smb_enable_smbus_mode(rmi_smb);
+ if (!ret)
+ break;
+
+ /* we failed enabling SMBus, try again later */
+ msleep(500);
+ }
+
+ if (ret < 0) {
+ dev_warn(&client->dev,
+ "failed to enable SMBus mode, giving up.\n");
+ pdata = dev_get_platdata(&rmi_smb->client->dev);
+ rmi_transport_enable(pdata, false);
+ }
+
+ return ret;
}

static const struct rmi_transport_ops rmi_smb_ops = {
--
2.7.4