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[2/2] i2c: stm32f7: do not set the STOP condition on error

Message ID 20220815111905.4090289-2-jorge@foundries.io
State Superseded
Delegated to: Patrice Chotard
Headers show
Series [1/2] i2c: stm32f7: fix clearing the control register | expand

Commit Message

Jorge Ramirez-Ortiz, Foundries Aug. 15, 2022, 11:19 a.m. UTC 
Sending the stop condition without waiting for TC has been
found to lock the bus.

Tested accessing the the NXP SE05X I2C device.

Signed-off-by: Jorge Ramirez-Ortiz <jorge@foundries.io>
---
 drivers/i2c/stm32f7_i2c.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

Comments

Oleksandr Suvorov Aug. 15, 2022, 1:15 p.m. UTC | #1 
Jorge,

On Mon, Aug 15, 2022 at 2:19 PM Jorge Ramirez-Ortiz <jorge@foundries.io> wrote:
>
> Sending the stop condition without waiting for TC has been
> found to lock the bus.
>
> Tested accessing the the NXP SE05X I2C device.

"the the" seems like a typo.

With this,
Reviewed-by: Oleksandr Suvorov <oleksandr.suvorov@foundries.io>

> Signed-off-by: Jorge Ramirez-Ortiz <jorge@foundries.io>
> ---
>  drivers/i2c/stm32f7_i2c.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c
> index 3a727e68ac..14827e5cec 100644
> --- a/drivers/i2c/stm32f7_i2c.c
> +++ b/drivers/i2c/stm32f7_i2c.c
> @@ -485,9 +485,11 @@ 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(&regs->cr2, mask);
> +       if (!ret) {
> +               /* End of transfer, send stop condition */
> +               mask = STM32_I2C_CR2_STOP;
> +               setbits_le32(&regs->cr2, mask);
> +       }
>
>         return stm32_i2c_check_end_of_message(i2c_priv);
>  }
> --
> 2.34.1
>
diff mbox series

Patch

diff --git a/drivers/i2c/stm32f7_i2c.c b/drivers/i2c/stm32f7_i2c.c
index 3a727e68ac..14827e5cec 100644
--- a/drivers/i2c/stm32f7_i2c.c
+++ b/drivers/i2c/stm32f7_i2c.c
@@ -485,9 +485,11 @@  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(&regs->cr2, mask);
+	if (!ret) {
+		/* End of transfer, send stop condition */
+		mask = STM32_I2C_CR2_STOP;
+		setbits_le32(&regs->cr2, mask);
+	}
 
 	return stm32_i2c_check_end_of_message(i2c_priv);
 }