Hi Alain,
On 9/9/22 18:06, Alain Volmat wrote:
Current function stm32_i2c_message_xfer is sending a STOP whatever the result of the transaction is. This can cause issues such as making the bus busy since the controller itself is already sending automatically a STOP when a NACK is generated.
Thanks to Jorge Ramirez-Ortiz for diagnosing and proposing a first fix for this. [1]
[1] https://lore.kernel.org/u-boot/20220815145211.31342-2-jorge@foundries.io/
Reported-by: Jorge Ramirez-Ortiz, Foundries jorge@foundries.io Signed-off-by: Jorge Ramirez-Ortiz jorge@foundries.io Signed-off-by: Alain Volmat alain.volmat@foss.st.com
drivers/i2c/stm32f7_i2c.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c index 0ec67b5c12..2db7f44d44 100644 --- a/drivers/i2c/stm32f7_i2c.c +++ b/drivers/i2c/stm32f7_i2c.c @@ -483,9 +483,9 @@ static int stm32_i2c_message_xfer(struct stm32_i2c_priv *i2c_priv, } }
- /* End of transfer, send stop condition */
- mask = STM32_I2C_CR2_STOP;
- setbits_le32(®s->cr2, mask);
/* End of transfer, send stop condition if appropriate */
if (!ret && !(status & (STM32_I2C_ISR_NACKF | STM32_I2C_ISR_ERRORS)))
setbits_le32(®s->cr2, STM32_I2C_CR2_STOP);return stm32_i2c_check_end_of_message(i2c_priv); }
Reviewed-by: Patrick Delaunay patrick.delaunay@foss.st.com Tested-by: Patrick Delaunay patrick.delaunay@foss.st.com [stm32mp157c-dk2]
No regression detection on ST Microelectonics board.
- No error trace on boot
- I2C probe command is OK
STM32MP> i2c probe Valid chip addresses: 28 33
- And other tests done with the 2 I2C devices STPMIC1 & STUSB1600 are ok: regulalor command
pmic status command
USB type C connection/deconnection
@Jorge: can you test also for your use-case, thanks
Thanks Patrick