diff options
| -rw-r--r-- | drivers/i2c/busses/i2c-rcar.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c index a7578f6da979..57083e91f2cf 100644 --- a/drivers/i2c/busses/i2c-rcar.c +++ b/drivers/i2c/busses/i2c-rcar.c @@ -85,6 +85,7 @@ /* ICFBSCR */ #define TCYC17 0x0f /* 17*Tcyc delay 1st bit between SDA and SCL */ +#define RCAR_MIN_DMA_LEN 8 #define RCAR_BUS_PHASE_START (MDBS | MIE | ESG) #define RCAR_BUS_PHASE_DATA (MDBS | MIE) @@ -412,8 +413,8 @@ static void rcar_i2c_dma(struct rcar_i2c_priv *priv) int len; /* Do various checks to see if DMA is feasible at all */ - if (IS_ERR(chan) || msg->len < 8 || !(msg->flags & I2C_M_DMA_SAFE) || - (read && priv->flags & ID_P_NO_RXDMA)) + if (IS_ERR(chan) || msg->len < RCAR_MIN_DMA_LEN || + !(msg->flags & I2C_M_DMA_SAFE) || (read && priv->flags & ID_P_NO_RXDMA)) return; if (read) { @@ -921,6 +922,9 @@ static int rcar_i2c_probe(struct platform_device *pdev) struct i2c_timings i2c_t; int irq, ret; + /* Otherwise logic will break because some bytes must always use PIO */ + BUILD_BUG_ON_MSG(RCAR_MIN_DMA_LEN < 3, "Invalid min DMA length"); + priv = devm_kzalloc(dev, sizeof(struct rcar_i2c_priv), GFP_KERNEL); if (!priv) return -ENOMEM; |