[PATCH V5 7/7] i2c: tegra: remove BUG, BUG_ON

Bitan Biswas
2019-06-11T10:51:14Z

Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
as needed. Remove BUG() and make Rx and Tx case handling
similar. Add WARN_ON_ONCE check for non-zero rx_fifo_avail
in tegra_i2c_empty_rx_fifo() and return new error
I2C_ERR_UNEXPECTED_STATUS.

Signed-off-by: Bitan Biswas <bbiswas@nvidia.com>
---
drivers/i2c/busses/i2c-tegra.c | 25 +++++++++++++++++--------
1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 0596c12..2c8f051 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -73,6 +73,7 @@
#define I2C_ERR_NO_ACK BIT(0)
#define I2C_ERR_ARBITRATION_LOST BIT(1)
#define I2C_ERR_UNKNOWN_INTERRUPT BIT(2)
+#define I2C_ERR_UNEXPECTED_STATUS BIT(3)

#define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
#define PACKET_HEADER0_PACKET_ID_SHIFT 16
@@ -516,15 +517,15 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
*/
if (rx_fifo_avail > 0 &&
(buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
- BUG_ON(buf_remaining > 3);
val = i2c_readl(i2c_dev, I2C_RX_FIFO);
val = cpu_to_le32(val);
memcpy(buf, &val, buf_remaining);
buf_remaining = 0;
rx_fifo_avail--;
}
+ if (WARN_ON_ONCE(rx_fifo_avail))
+ return -EINVAL;

- BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
i2c_dev->msg_buf_remaining = buf_remaining;
i2c_dev->msg_buf = buf;

@@ -582,7 +583,6 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
*/
if (tx_fifo_avail > 0 &&
(buf_remaining > 0 && buf_remaining < BYTES_PER_FIFO_WORD)) {
- BUG_ON(buf_remaining > 3);
memcpy(&val, buf, buf_remaining);
val = le32_to_cpu(val);

@@ -848,10 +848,16 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)

if (!i2c_dev->is_curr_dma_xfer) {
if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
- if (i2c_dev->msg_buf_remaining)
- tegra_i2c_empty_rx_fifo(i2c_dev);
- else
- BUG();
+ if (i2c_dev->msg_buf_remaining) {
+ if (tegra_i2c_empty_rx_fifo(i2c_dev)) {
+ i2c_dev->msg_err |=
+ I2C_ERR_UNEXPECTED_STATUS;
+ goto err;
+ }
+ } else {
+ tegra_i2c_mask_irq(i2c_dev,
+ I2C_INT_RX_FIFO_DATA_REQ);
+ }
}

if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
@@ -877,7 +883,10 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
if (status & I2C_INT_PACKET_XFER_COMPLETE) {
if (i2c_dev->is_curr_dma_xfer)
i2c_dev->msg_buf_remaining = 0;
- BUG_ON(i2c_dev->msg_buf_remaining);
+ if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining)) {
+ i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT;
+ goto err;
+ }
complete(&i2c_dev->msg_complete);
}
goto done;
--
2.7.4