diff options
Diffstat (limited to 'drivers/media/platform/stm32/stm32-cec.c')
| -rw-r--r-- | drivers/media/platform/stm32/stm32-cec.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/media/platform/stm32/stm32-cec.c b/drivers/media/platform/stm32/stm32-cec.c index 7c496bc1cf38..8a86b2cc22fa 100644 --- a/drivers/media/platform/stm32/stm32-cec.c +++ b/drivers/media/platform/stm32/stm32-cec.c @@ -56,6 +56,13 @@ #define ALL_TX_IT (TXEND | TXBR | TXACKE | TXERR | TXUDR | ARBLST) #define ALL_RX_IT (RXEND | RXBR | RXACKE | RXOVR) +/* + * 400 ms is the time it takes for one 16 byte message to be + * transferred and 5 is the maximum number of retries. Add + * another 100 ms as a margin. + */ +#define CEC_XFER_TIMEOUT_MS (5 * 400 + 100) + struct stm32_cec { struct cec_adapter *adap; struct device *dev; @@ -188,7 +195,11 @@ static int stm32_cec_adap_log_addr(struct cec_adapter *adap, u8 logical_addr) { struct stm32_cec *cec = adap->priv; u32 oar = (1 << logical_addr) << 16; + u32 val; + /* Poll every 100µs the register CEC_CR to wait end of transmission */ + regmap_read_poll_timeout(cec->regmap, CEC_CR, val, !(val & TXSOM), + 100, CEC_XFER_TIMEOUT_MS * 1000); regmap_update_bits(cec->regmap, CEC_CR, CECEN, 0); if (logical_addr == CEC_LOG_ADDR_INVALID) |