| From 20569a4897a7f13a79ab4af8f874a97cbf1aafb1 Mon Sep 17 00:00:00 2001 |
| From: Tali Perry <tali.perry1@gmail.com> |
| Date: Wed, 5 Mar 2025 11:10:42 +0200 |
| Subject: [PATCH v3] i2c: npcm: Add clock toggle recovery |
| |
| During init of the bus, the module checks that the bus is idle. |
| If one of the lines are stuck try to recover them first before failing. |
| Sometimes SDA and SCL are low if improper reset occurs (e.g., reboot). |
| |
| Signed-off-by: Tali Perry <tali.perry1@gmail.com> |
| Signed-off-by: Mohammed Elbadry <mohammed.0.elbadry@gmail.com> |
| --- |
| drivers/i2c/busses/i2c-npcm7xx.c | 12 ++++++++---- |
| 1 file changed, 8 insertions(+), 4 deletions(-) |
| |
| diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c |
| index 2fe68615942e..f05cae20cb27 100644 |
| --- a/drivers/i2c/busses/i2c-npcm7xx.c |
| +++ b/drivers/i2c/busses/i2c-npcm7xx.c |
| @@ -1967,10 +1967,14 @@ static int npcm_i2c_init_module(struct npcm_i2c *bus, enum i2c_mode mode, |
| |
| /* Check HW is OK: SDA and SCL should be high at this point. */ |
| if ((npcm_i2c_get_SDA(&bus->adap) == 0) || (npcm_i2c_get_SCL(&bus->adap) == 0)) { |
| - dev_err(bus->dev, "I2C%d init fail: lines are low\n", bus->num); |
| - dev_err(bus->dev, "SDA=%d SCL=%d\n", npcm_i2c_get_SDA(&bus->adap), |
| - npcm_i2c_get_SCL(&bus->adap)); |
| - return -ENXIO; |
| + dev_warn(bus->dev, " I2C%d SDA=%d SCL=%d, attempt recover\n", bus->num, |
| + npcm_i2c_get_SDA(&bus->adap), npcm_i2c_get_SCL(&bus->adap)); |
| + if (npcm_i2c_recovery_tgclk(&bus->adap)) { |
| + dev_err(bus->dev, "I2C%d init fail: lines are low, SDA=%d SCL=%d\n", |
| + bus->num, npcm_i2c_get_SDA(&bus->adap), |
| + npcm_i2c_get_SCL(&bus->adap)); |
| + return -ENXIO; |
| + } |
| } |
| |
| npcm_i2c_int_enable(bus, true); |
| -- |
| 2.49.0.472.ge94155a9ec-goog |
| |
