can: m_can: is_lec_err(): clean up LEC error handling

The PSR register contains among other the error for the CAN
arbitration phase (LEC bits) and CAN data phase (DLEC bits).

Prepare is_lec_err() to be called with the (D)LEC value only instead
of the whole PSR register. While there rename LEC_UNUSED to
LEC_NO_CHANGE to match the latest M_CAN reference manual.

Link: https://lore.kernel.org/all/20221019211611.1605764-1-mkl@pengutronix.de
Reviewed-by: Chandrasekar Ramakrishnan <rcsekar@samsung.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/m_can/m_can.c b/drivers/net/can/m_can/m_can.c
index dcb5825..ebdd3c1 100644 (file)
--- a/drivers/net/can/m_can/m_can.c
+++ b/drivers/net/can/m_can/m_can.c
@@ -816,11 +816,9 @@ static void m_can_handle_other_err(struct net_device *dev, u32 irqstatus)
                netdev_err(dev, "Message RAM access failure occurred\n");
 }
 
-static inline bool is_lec_err(u32 psr)
+static inline bool is_lec_err(u8 lec)
 {
-       psr &= LEC_UNUSED;
-
-       return psr && (psr != LEC_UNUSED);
+       return lec != LEC_NO_ERROR && lec != LEC_NO_CHANGE;
 }
 
 static inline bool m_can_is_protocol_err(u32 irqstatus)
@@ -875,9 +873,12 @@ static int m_can_handle_bus_errors(struct net_device *dev, u32 irqstatus,
                work_done += m_can_handle_lost_msg(dev);
 
        /* handle lec errors on the bus */
-       if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
-           is_lec_err(psr))
-               work_done += m_can_handle_lec_err(dev, psr & LEC_UNUSED);
+       if (cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) {
+               u8 lec = FIELD_GET(PSR_LEC_MASK, psr);
+
+               if (is_lec_err(lec))
+                       work_done += m_can_handle_lec_err(dev, lec);
+       }
 
        /* handle protocol errors in arbitration phase */
        if ((cdev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&

diff --git a/drivers/net/can/m_can/m_can.h b/drivers/net/can/m_can/m_can.h
index 4c0267f..52563c0 100644 (file)
--- a/drivers/net/can/m_can/m_can.h
+++ b/drivers/net/can/m_can/m_can.h
@@ -38,7 +38,7 @@ enum m_can_lec_type {
        LEC_BIT1_ERROR,
        LEC_BIT0_ERROR,
        LEC_CRC_ERROR,
-       LEC_UNUSED,
+       LEC_NO_CHANGE,
 };
 
 enum m_can_mram_cfg {