The next MTDR command should be filled before the last receive command is
fininshed. Otherwise, a NACK will be sent when the current MTDR command
is finished. It causes lpi2c cannot send the next chunk data
successfully.
Signed-off-by: Clark Wang <[email protected]>
---
V2 changes:
- New patch added in V2
---
drivers/i2c/busses/i2c-imx-lpi2c.c | 43 +++++++++++++++++++++++++-----
1 file changed, 36 insertions(+), 7 deletions(-)
diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c
index 3c0f16a79185..8d908b9b5112 100644
--- a/drivers/i2c/busses/i2c-imx-lpi2c.c
+++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
@@ -112,6 +112,7 @@ struct lpi2c_imx_struct {
struct completion complete;
unsigned int msglen;
unsigned int delivered;
+ unsigned int remain_chunk_num;
unsigned int block_data;
unsigned int bitrate;
unsigned int txfifosize;
@@ -413,6 +414,28 @@ static void lpi2c_imx_write_txfifo(struct lpi2c_imx_struct *lpi2c_imx)
complete(&lpi2c_imx->complete);
}
+static void lpi2c_imx_pio_push_rx_cmd(struct lpi2c_imx_struct *lpi2c_imx)
+{
+ unsigned int remaining, temp;
+ u8 last_chunk_num = lpi2c_imx->msglen % CHUNK_DATA;
+
+ if (lpi2c_imx->remain_chunk_num > 0 &&
+ (lpi2c_imx->delivered % CHUNK_DATA) > (CHUNK_DATA >> 1)) {
+ if ((readl(lpi2c_imx->base + LPI2C_MFSR) & 0xff) <=
+ (lpi2c_imx->rxfifosize >> 1)) {
+ if (last_chunk_num)
+ remaining = (lpi2c_imx->remain_chunk_num - 1) *
+ CHUNK_DATA + last_chunk_num;
+ else
+ remaining = lpi2c_imx->remain_chunk_num * CHUNK_DATA;
+ temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1;
+ temp |= (RECV_DATA << 8);
+ writel(temp, lpi2c_imx->base + LPI2C_MTDR);
+ lpi2c_imx->remain_chunk_num--;
+ }
+ }
+}
+
static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
{
unsigned int blocklen, remaining;
@@ -420,10 +443,16 @@ static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
do {
data = readl(lpi2c_imx->base + LPI2C_MRDR);
- if (data & MRDR_RXEMPTY)
- break;
+ if (data & MRDR_RXEMPTY) {
+ if (lpi2c_imx->delivered == lpi2c_imx->msglen ||
+ lpi2c_imx->block_data)
+ break;
+ else
+ continue;
+ }
lpi2c_imx->rx_buf[lpi2c_imx->delivered++] = data & 0xff;
+ lpi2c_imx_pio_push_rx_cmd(lpi2c_imx);
} while (1);
/*
@@ -451,13 +480,9 @@ static void lpi2c_imx_read_rxfifo(struct lpi2c_imx_struct *lpi2c_imx)
temp = remaining;
temp |= (RECV_DATA << 8);
writel(temp, lpi2c_imx->base + LPI2C_MTDR);
- } else if (!(lpi2c_imx->delivered & 0xff)) {
- temp = (remaining > CHUNK_DATA ? CHUNK_DATA : remaining) - 1;
- temp |= (RECV_DATA << 8);
- writel(temp, lpi2c_imx->base + LPI2C_MTDR);
}
- lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE);
+ lpi2c_imx_intctrl(lpi2c_imx, MIER_RDIE | MIER_NDIE);
}
static void lpi2c_imx_write(struct lpi2c_imx_struct *lpi2c_imx,
@@ -477,6 +502,10 @@ static void lpi2c_imx_read(struct lpi2c_imx_struct *lpi2c_imx,
lpi2c_imx->block_data = msgs->flags & I2C_M_RECV_LEN;
lpi2c_imx_set_rx_watermark(lpi2c_imx);
+ if (msgs->len > CHUNK_DATA) {
+ temp = CHUNK_DATA - 1;
+ lpi2c_imx->remain_chunk_num = DIV_ROUND_UP(msgs->len, CHUNK_DATA) - 1;
+ }
temp = msgs->len > CHUNK_DATA ? CHUNK_DATA - 1 : msgs->len - 1;
temp |= (RECV_DATA << 8);
writel(temp, lpi2c_imx->base + LPI2C_MTDR);
--
2.25.1