On 03/24/2018 11:56 PM, Wolfram Sang wrote: > On Wed, Mar 21, 2018 at 05:49:00PM +0100, Pierre-Yves MORDRET wrote: >> Feature prevents I2C lock-ups. Mechanism resets I2C state machine >> and releases SCL/SDA signals but preserves I2C registers. >> >> Signed-off-by: Pierre-Yves MORDRET <pierre-yves.mord...@st.com> >> --- >> Version history: >> v1: >> * Initial >> v2: >> * Don't use i2c engine recovery mechanism since driver >> procedure only recover master and not the slave. > > s/recovery/release/ throughout the patch, please. Recovery is really > something else. Also, I think the dev_info's are too noisy in the log > files. I'd think the whole driver could be lifted from quite some > logging... >
ok. will do. Do you have example of info's that we should get rid of ? >> --- >> --- >> drivers/i2c/busses/i2c-stm32f7.c | 27 ++++++++++++++++++++++++--- >> 1 file changed, 24 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/i2c/busses/i2c-stm32f7.c >> b/drivers/i2c/busses/i2c-stm32f7.c >> index 91f73e0..9a9c469 100644 >> --- a/drivers/i2c/busses/i2c-stm32f7.c >> +++ b/drivers/i2c/busses/i2c-stm32f7.c >> @@ -718,6 +718,20 @@ static void stm32f7_i2c_smbus_reload(struct >> stm32f7_i2c_dev *i2c_dev) >> writel_relaxed(cr2, i2c_dev->base + STM32F7_I2C_CR2); >> } >> >> +static int stm32f7_i2c_recover_bus(struct i2c_adapter *i2c_adap) >> +{ >> + struct stm32f7_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap); >> + >> + dev_info(i2c_dev->dev, "Trying to recover bus\n"); >> + >> + stm32f7_i2c_clr_bits(i2c_dev->base + STM32F7_I2C_CR1, >> + STM32F7_I2C_CR1_PE); >> + >> + stm32f7_i2c_hw_config(i2c_dev); >> + >> + return 0; >> +} >> + >> static int stm32f7_i2c_wait_free_bus(struct stm32f7_i2c_dev *i2c_dev) >> { >> u32 status; >> @@ -727,12 +741,18 @@ static int stm32f7_i2c_wait_free_bus(struct >> stm32f7_i2c_dev *i2c_dev) >> status, >> !(status & STM32F7_I2C_ISR_BUSY), >> 10, 1000); >> + if (!ret) >> + return 0; >> + >> + dev_info(i2c_dev->dev, "bus busy\n"); >> + >> + ret = stm32f7_i2c_recover_bus(&i2c_dev->adap); >> if (ret) { >> - dev_dbg(i2c_dev->dev, "bus busy\n"); >> - ret = -EBUSY; >> + dev_err(i2c_dev->dev, "Failed to recover the bus (%d)\n", ret); >> + return ret; >> } >> >> - return ret; >> + return -EBUSY; >> } >> >> static void stm32f7_i2c_xfer_msg(struct stm32f7_i2c_dev *i2c_dev, >> @@ -1474,6 +1494,7 @@ static irqreturn_t stm32f7_i2c_isr_error(int irq, void >> *data) >> if (status & STM32F7_I2C_ISR_BERR) { >> dev_err(dev, "<%s>: Bus error\n", __func__); >> writel_relaxed(STM32F7_I2C_ICR_BERRCF, base + STM32F7_I2C_ICR); >> + stm32f7_i2c_recover_bus(&i2c_dev->adap); >> f7_msg->result = -EIO; >> } >> >> -- >> 2.7.4 >>