diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 53f18b351f538c04c9d3faac806afefc3f274fff..6b3ba7e5723aa1b9ac3f6814306b08e27b009b33 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -782,6 +782,7 @@ config I2C_JZ4780
config I2C_KEBA
tristate "KEBA I2C controller support"
depends on HAS_IOMEM
+ depends on KEBA_CP500 || COMPILE_TEST
select AUXILIARY_BUS
help
This driver supports the I2C controller found in KEBA system FPGA
diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index 080204182bb5ace8717af5cdbe050045e35be847..f31d352d98b57410f42db51f5ec95e02840f33e0 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -523,6 +523,7 @@ int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
void __i2c_dw_disable(struct dw_i2c_dev *dev)
{
+ struct i2c_timings *t = &dev->timings;
unsigned int raw_intr_stats;
unsigned int enable;
int timeout = 100;
@@ -535,6 +536,19 @@ void __i2c_dw_disable(struct dw_i2c_dev *dev)
abort_needed = raw_intr_stats & DW_IC_INTR_MST_ON_HOLD;
if (abort_needed) {
+ if (!(enable & DW_IC_ENABLE_ENABLE)) {
+ regmap_write(dev->map, DW_IC_ENABLE, DW_IC_ENABLE_ENABLE);
+ /*
+ * Wait 10 times the signaling period of the highest I2C
+ * transfer supported by the driver (for 400KHz this is
+ * 25us) to ensure the I2C ENABLE bit is already set
+ * as described in the DesignWare I2C databook.
+ */
+ fsleep(DIV_ROUND_CLOSEST_ULL(10 * MICRO, t->bus_freq_hz));
+ /* Set ENABLE bit before setting ABORT */
+ enable |= DW_IC_ENABLE_ENABLE;
+ }
+
regmap_write(dev->map, DW_IC_ENABLE, enable | DW_IC_ENABLE_ABORT);
ret = regmap_read_poll_timeout(dev->map, DW_IC_ENABLE, enable,
!(enable & DW_IC_ENABLE_ABORT), 10,
diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h
index 1ac2afd03a0a581d81e6900d5dbd1ca43058863e..8e8854ec988258ece4378a872ca0b3beb6fbac94 100644
--- a/drivers/i2c/busses/i2c-designware-core.h
+++ b/drivers/i2c/busses/i2c-designware-core.h
@@ -108,6 +108,7 @@
DW_IC_INTR_RX_UNDER | \
DW_IC_INTR_RD_REQ)
+#define DW_IC_ENABLE_ENABLE BIT(0)
#define DW_IC_ENABLE_ABORT BIT(1)
#define DW_IC_STATUS_ACTIVITY BIT(0)
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index e46f1b22c3601aa361e11e532fa0c5dfe72fb03d..e8ac9a7bf0b3d232335357e2e6aac6abde4c6a1f 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -271,6 +271,34 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
__i2c_dw_write_intr_mask(dev, DW_IC_INTR_MASTER_MASK);
}
+/*
+ * This function waits for the controller to be idle before disabling I2C
+ * When the controller is not in the IDLE state, the MST_ACTIVITY bit
+ * (IC_STATUS[5]) is set.
+ *
+ * Values:
+ * 0x1 (ACTIVE): Controller not idle
+ * 0x0 (IDLE): Controller is idle
+ *
+ * The function is called after completing the current transfer.
+ *
+ * Returns:
+ * False when the controller is in the IDLE state.
+ * True when the controller is in the ACTIVE state.
+ */
+static bool i2c_dw_is_controller_active(struct dw_i2c_dev *dev)
+{
+ u32 status;
+
+ regmap_read(dev->map, DW_IC_STATUS, &status);
+ if (!(status & DW_IC_STATUS_MASTER_ACTIVITY))
+ return false;
+
+ return regmap_read_poll_timeout(dev->map, DW_IC_STATUS, status,
+ !(status & DW_IC_STATUS_MASTER_ACTIVITY),
+ 1100, 20000) != 0;
+}
+
static int i2c_dw_check_stopbit(struct dw_i2c_dev *dev)
{
u32 val;
@@ -806,6 +834,16 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
goto done;
}
+ /*
+ * This happens rarely (~1:500) and is hard to reproduce. Debug trace
+ * showed that IC_STATUS had value of 0x23 when STOP_DET occurred,
+ * if disable IC_ENABLE.ENABLE immediately that can result in
+ * IC_RAW_INTR_STAT.MASTER_ON_HOLD holding SCL low. Check if
+ * controller is still ACTIVE before disabling I2C.
+ */
+ if (i2c_dw_is_controller_active(dev))
+ dev_err(dev->dev, "controller active\n");
+
/*
* We must disable the adapter before returning and signaling the end
* of the current transfer. Otherwise the hardware might continue
diff --git a/drivers/i2c/busses/i2c-synquacer.c b/drivers/i2c/busses/i2c-synquacer.c
index 4eccbcd0fbfc00b7f67875e880054bdd06515be4..bbb9062669e4b2be7cc99081dbd3bf2cb9537677 100644
--- a/drivers/i2c/busses/i2c-synquacer.c
+++ b/drivers/i2c/busses/i2c-synquacer.c
@@ -550,12 +550,13 @@ static int synquacer_i2c_probe(struct platform_device *pdev)
device_property_read_u32(&pdev->dev, "socionext,pclk-rate",
&i2c->pclkrate);
- pclk = devm_clk_get_enabled(&pdev->dev, "pclk");
+ pclk = devm_clk_get_optional_enabled(&pdev->dev, "pclk");
if (IS_ERR(pclk))
return dev_err_probe(&pdev->dev, PTR_ERR(pclk),
"failed to get and enable clock\n");
- i2c->pclkrate = clk_get_rate(pclk);
+ if (pclk)
+ i2c->pclkrate = clk_get_rate(pclk);
if (i2c->pclkrate < SYNQUACER_I2C_MIN_CLK_RATE ||
i2c->pclkrate > SYNQUACER_I2C_MAX_CLK_RATE)
diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c
index 4c89aad02451dbe46cb33ba25441f40d0ea9623b..1d68177241a6b3b513bf5d356b6b11ef65f15b53 100644
--- a/drivers/i2c/busses/i2c-xiic.c
+++ b/drivers/i2c/busses/i2c-xiic.c
@@ -1337,8 +1337,8 @@ static int xiic_i2c_probe(struct platform_device *pdev)
return 0;
err_pm_disable:
- pm_runtime_set_suspended(&pdev->dev);
pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
return ret;
}