[PATCH v2 09/11] can: tcan4x5x: Fix use of register error status mask

From: Markus Schneider-Pargmann
Date: Tue Dec 06 2022 - 06:58:28 EST


TCAN4X5X_ERROR_STATUS is not a status register that needs clearing
during interrupt handling. Instead this is a masking register that masks
error interrupts. Writing TCAN4X5X_CLEAR_ALL_INT to this register
effectively masks everything.

Rename the register and mask all error interrupts only once by writing
to the register in tcan4x5x_init.

Fixes: 5443c226ba91 ("can: tcan4x5x: Add tcan4x5x driver to the kernel")
Signed-off-by: Markus Schneider-Pargmann <msp@xxxxxxxxxxxx>
---

Notes:
v2:
- Add fixes tag

drivers/net/can/m_can/tcan4x5x-core.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/can/m_can/tcan4x5x-core.c b/drivers/net/can/m_can/tcan4x5x-core.c
index 1fec394b3517..efa2381bf85b 100644
--- a/drivers/net/can/m_can/tcan4x5x-core.c
+++ b/drivers/net/can/m_can/tcan4x5x-core.c
@@ -10,7 +10,7 @@
#define TCAN4X5X_DEV_ID1 0x04
#define TCAN4X5X_REV 0x08
#define TCAN4X5X_STATUS 0x0C
-#define TCAN4X5X_ERROR_STATUS 0x10
+#define TCAN4X5X_ERROR_STATUS_MASK 0x10
#define TCAN4X5X_CONTROL 0x14

#define TCAN4X5X_CONFIG 0x800
@@ -204,12 +204,7 @@ static int tcan4x5x_clear_interrupts(struct m_can_classdev *cdev)
if (ret)
return ret;

- ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_INT_FLAGS,
- TCAN4X5X_CLEAR_ALL_INT);
- if (ret)
- return ret;
-
- return tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_ERROR_STATUS,
+ return tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_INT_FLAGS,
TCAN4X5X_CLEAR_ALL_INT);
}

@@ -229,6 +224,11 @@ static int tcan4x5x_init(struct m_can_classdev *cdev)
if (ret)
return ret;

+ ret = tcan4x5x_write_tcan_reg(cdev, TCAN4X5X_ERROR_STATUS_MASK,
+ TCAN4X5X_CLEAR_ALL_INT);
+ if (ret)
+ return ret;
+
/* Zero out the MCAN buffers */
ret = m_can_init_ram(cdev);
if (ret)
--
2.38.1