@@ -332,7 +332,7 @@ static void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
u32 val;
u16 addr;
u8 len;
- int i;
+ int i, j;
/* TEF */
priv->tef.head = 0;
@@ -370,6 +370,23 @@ static void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
prev_rx_ring->obj_num;
prev_rx_ring = rx_ring;
+
+ /* FIFO increment RX tail pointer */
+ addr = MCP251XFD_REG_FIFOCON(rx_ring->fifo_nr);
+ val = MCP251XFD_REG_FIFOCON_UINC;
+ len = mcp251xfd_cmd_prepare_write_reg(priv, &rx_ring->uinc_buf,
+ addr, val, val);
+
+ for (j = 0; j < ARRAY_SIZE(rx_ring->uinc_xfer); j++) {
+ struct spi_transfer *xfer;
+
+ xfer = &rx_ring->uinc_xfer[j];
+ xfer->tx_buf = &rx_ring->uinc_buf;
+ xfer->len = len;
+ xfer->cs_change = 1;
+ xfer->cs_change_delay.value = 0;
+ xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS;
+ }
}
}
@@ -1440,13 +1457,7 @@ mcp251xfd_handle_rxif_one(struct mcp251xfd_priv *priv,
if (err)
stats->rx_fifo_errors++;
- ring->tail++;
-
- /* finally increment the RX pointer */
- return regmap_update_bits(priv->map_reg,
- MCP251XFD_REG_FIFOCON(ring->fifo_nr),
- GENMASK(15, 8),
- MCP251XFD_REG_FIFOCON_UINC);
+ return 0;
}
static inline int
@@ -1478,6 +1489,8 @@ mcp251xfd_handle_rxif_ring(struct mcp251xfd_priv *priv,
return err;
while ((len = mcp251xfd_get_rx_linear_len(ring))) {
+ struct spi_transfer *last_xfer;
+
rx_tail = mcp251xfd_get_rx_tail(ring);
err = mcp251xfd_rx_obj_read(priv, ring, hw_rx_obj,
@@ -1492,6 +1505,28 @@ mcp251xfd_handle_rxif_ring(struct mcp251xfd_priv *priv,
if (err)
return err;
}
+
+ /* Increment the RX FIFO tail pointer 'len' times in a
+ * single SPI message.
+ */
+ ring->tail += len;
+
+ /* Note:
+ *
+ * "cs_change == 1" on the last transfer results in an
+ * active chip select after the complete SPI
+ * message. This causes the controller to interpret
+ * the next register access as data. Temporary set
+ * "cs_change" of the last transfer to "0" to properly
+ * deactivate the chip select at the end of the
+ * message.
+ */
+ last_xfer = &ring->uinc_xfer[len - 1];
+ last_xfer->cs_change = 0;
+ err = spi_sync_transfer(priv->spi, ring->uinc_xfer, len);
+ last_xfer->cs_change = 1;
+ if (err)
+ return err;
}
return 0;
@@ -528,6 +528,8 @@ struct mcp251xfd_rx_ring {
u8 obj_num;
u8 obj_size;
+ union mcp251xfd_write_reg_buf uinc_buf;
+ struct spi_transfer uinc_xfer[MCP251XFD_RX_OBJ_NUM_MAX];
struct mcp251xfd_hw_rx_obj_canfd obj[];
};