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-rw-r--r--drivers/net/dsa/sja1105/sja1105.h2
-rw-r--r--drivers/net/dsa/sja1105/sja1105_spi.c164
2 files changed, 85 insertions, 81 deletions
diff --git a/drivers/net/dsa/sja1105/sja1105.h b/drivers/net/dsa/sja1105/sja1105.h
index 657c492d39a0..0ef97a916707 100644
--- a/drivers/net/dsa/sja1105/sja1105.h
+++ b/drivers/net/dsa/sja1105/sja1105.h
@@ -121,7 +121,7 @@ int sja1105_static_config_reload(struct sja1105_private *priv);
/* From sja1105_spi.c */
int sja1105_xfer_buf(const struct sja1105_private *priv,
sja1105_spi_rw_mode_t rw, u64 reg_addr,
- void *packed_buf, size_t size_bytes);
+ u8 *buf, size_t len);
int sja1105_xfer_u32(const struct sja1105_private *priv,
sja1105_spi_rw_mode_t rw, u64 reg_addr, u32 *value);
int sja1105_xfer_u64(const struct sja1105_private *priv,
diff --git a/drivers/net/dsa/sja1105/sja1105_spi.c b/drivers/net/dsa/sja1105/sja1105_spi.c
index a7532fb3c162..e25724d99594 100644
--- a/drivers/net/dsa/sja1105/sja1105_spi.c
+++ b/drivers/net/dsa/sja1105/sja1105_spi.c
@@ -10,8 +10,12 @@
#define SJA1105_SIZE_RESET_CMD 4
#define SJA1105_SIZE_SPI_MSG_HEADER 4
#define SJA1105_SIZE_SPI_MSG_MAXLEN (64 * 4)
-#define SJA1105_SIZE_SPI_TRANSFER_MAX \
- (SJA1105_SIZE_SPI_MSG_HEADER + SJA1105_SIZE_SPI_MSG_MAXLEN)
+
+struct sja1105_chunk {
+ u8 *buf;
+ size_t len;
+ u64 reg_addr;
+};
static void
sja1105_spi_message_pack(void *buf, const struct sja1105_spi_message *msg)
@@ -25,61 +29,98 @@ sja1105_spi_message_pack(void *buf, const struct sja1105_spi_message *msg)
sja1105_pack(buf, &msg->address, 24, 4, size);
}
+#define sja1105_hdr_xfer(xfers, chunk) \
+ ((xfers) + 2 * (chunk))
+#define sja1105_chunk_xfer(xfers, chunk) \
+ ((xfers) + 2 * (chunk) + 1)
+#define sja1105_hdr_buf(hdr_bufs, chunk) \
+ ((hdr_bufs) + (chunk) * SJA1105_SIZE_SPI_MSG_HEADER)
+
/* If @rw is:
* - SPI_WRITE: creates and sends an SPI write message at absolute
- * address reg_addr, taking size_bytes from *packed_buf
+ * address reg_addr, taking @len bytes from *buf
* - SPI_READ: creates and sends an SPI read message from absolute
- * address reg_addr, writing size_bytes into *packed_buf
- *
- * This function should only be called if it is priorly known that
- * @size_bytes is smaller than SIZE_SPI_MSG_MAXLEN. Larger packed buffers
- * are chunked in smaller pieces by sja1105_xfer_long_buf below.
+ * address reg_addr, writing @len bytes into *buf
*/
int sja1105_xfer_buf(const struct sja1105_private *priv,
sja1105_spi_rw_mode_t rw, u64 reg_addr,
- void *packed_buf, size_t size_bytes)
+ u8 *buf, size_t len)
{
- const int msg_len = size_bytes + SJA1105_SIZE_SPI_MSG_HEADER;
- u8 tx_buf[SJA1105_SIZE_SPI_TRANSFER_MAX] = {0};
- u8 rx_buf[SJA1105_SIZE_SPI_TRANSFER_MAX] = {0};
- struct spi_device *spi = priv->spidev;
- struct sja1105_spi_message msg = {0};
- struct spi_transfer xfer = {
- .tx_buf = tx_buf,
- .rx_buf = rx_buf,
- .len = msg_len,
+ struct sja1105_chunk chunk = {
+ .len = min_t(size_t, len, SJA1105_SIZE_SPI_MSG_MAXLEN),
+ .reg_addr = reg_addr,
+ .buf = buf,
};
- struct spi_message m;
- int rc;
-
- if (msg_len > SJA1105_SIZE_SPI_TRANSFER_MAX)
- return -ERANGE;
+ struct spi_device *spi = priv->spidev;
+ struct spi_transfer *xfers;
+ int num_chunks;
+ int rc, i = 0;
+ u8 *hdr_bufs;
- msg.access = rw;
- msg.address = reg_addr;
- if (rw == SPI_READ)
- msg.read_count = size_bytes / 4;
+ num_chunks = DIV_ROUND_UP(len, SJA1105_SIZE_SPI_MSG_MAXLEN);
- sja1105_spi_message_pack(tx_buf, &msg);
+ /* One transfer for each message header, one for each message
+ * payload (chunk).
+ */
+ xfers = kcalloc(2 * num_chunks, sizeof(struct spi_transfer),
+ GFP_KERNEL);
+ if (!xfers)
+ return -ENOMEM;
- if (rw == SPI_WRITE)
- memcpy(tx_buf + SJA1105_SIZE_SPI_MSG_HEADER,
- packed_buf, size_bytes);
+ /* Packed buffers for the num_chunks SPI message headers,
+ * stored as a contiguous array
+ */
+ hdr_bufs = kcalloc(num_chunks, SJA1105_SIZE_SPI_MSG_HEADER,
+ GFP_KERNEL);
+ if (!hdr_bufs) {
+ kfree(xfers);
+ return -ENOMEM;
+ }
- spi_message_init(&m);
- spi_message_add_tail(&xfer, &m);
+ for (i = 0; i < num_chunks; i++) {
+ struct spi_transfer *chunk_xfer = sja1105_chunk_xfer(xfers, i);
+ struct spi_transfer *hdr_xfer = sja1105_hdr_xfer(xfers, i);
+ u8 *hdr_buf = sja1105_hdr_buf(hdr_bufs, i);
+ struct sja1105_spi_message msg;
+
+ /* Populate the transfer's header buffer */
+ msg.address = chunk.reg_addr;
+ msg.access = rw;
+ if (rw == SPI_READ)
+ msg.read_count = chunk.len / 4;
+ else
+ /* Ignored */
+ msg.read_count = 0;
+ sja1105_spi_message_pack(hdr_buf, &msg);
+ hdr_xfer->tx_buf = hdr_buf;
+ hdr_xfer->len = SJA1105_SIZE_SPI_MSG_HEADER;
+
+ /* Populate the transfer's data buffer */
+ if (rw == SPI_READ)
+ chunk_xfer->rx_buf = chunk.buf;
+ else
+ chunk_xfer->tx_buf = chunk.buf;
+ chunk_xfer->len = chunk.len;
+
+ /* Calculate next chunk */
+ chunk.buf += chunk.len;
+ chunk.reg_addr += chunk.len / 4;
+ chunk.len = min_t(size_t, (ptrdiff_t)(buf + len - chunk.buf),
+ SJA1105_SIZE_SPI_MSG_MAXLEN);
+
+ /* De-assert the chip select after each chunk. */
+ if (chunk.len)
+ chunk_xfer->cs_change = 1;
+ }
- rc = spi_sync(spi, &m);
- if (rc < 0) {
+ rc = spi_sync_transfer(spi, xfers, 2 * num_chunks);
+ if (rc < 0)
dev_err(&spi->dev, "SPI transfer failed: %d\n", rc);
- return rc;
- }
- if (rw == SPI_READ)
- memcpy(packed_buf, rx_buf + SJA1105_SIZE_SPI_MSG_HEADER,
- size_bytes);
+ kfree(hdr_bufs);
+ kfree(xfers);
- return 0;
+ return rc;
}
/* If @rw is:
@@ -134,43 +175,6 @@ int sja1105_xfer_u32(const struct sja1105_private *priv,
return rc;
}
-/* Should be used if a @packed_buf larger than SJA1105_SIZE_SPI_MSG_MAXLEN
- * must be sent/received. Splitting the buffer into chunks and assembling
- * those into SPI messages is done automatically by this function.
- */
-static int sja1105_xfer_long_buf(const struct sja1105_private *priv,
- sja1105_spi_rw_mode_t rw, u64 base_addr,
- void *packed_buf, u64 buf_len)
-{
- struct chunk {
- void *buf_ptr;
- int len;
- u64 spi_address;
- } chunk;
- int distance_to_end;
- int rc;
-
- /* Initialize chunk */
- chunk.buf_ptr = packed_buf;
- chunk.spi_address = base_addr;
- chunk.len = min_t(int, buf_len, SJA1105_SIZE_SPI_MSG_MAXLEN);
-
- while (chunk.len) {
- rc = sja1105_xfer_buf(priv, rw, chunk.spi_address,
- chunk.buf_ptr, chunk.len);
- if (rc < 0)
- return rc;
-
- chunk.buf_ptr += chunk.len;
- chunk.spi_address += chunk.len / 4;
- distance_to_end = (uintptr_t)(packed_buf + buf_len -
- chunk.buf_ptr);
- chunk.len = min(distance_to_end, SJA1105_SIZE_SPI_MSG_MAXLEN);
- }
-
- return 0;
-}
-
/* Back-ported structure from UM11040 Table 112.
* Reset control register (addr. 100440h)
* In the SJA1105 E/T, only warm_rst and cold_rst are
@@ -433,8 +437,8 @@ int sja1105_static_config_upload(struct sja1105_private *priv)
/* Wait for the switch to come out of reset */
usleep_range(1000, 5000);
/* Upload the static config to the device */
- rc = sja1105_xfer_long_buf(priv, SPI_WRITE, regs->config,
- config_buf, buf_len);
+ rc = sja1105_xfer_buf(priv, SPI_WRITE, regs->config,
+ config_buf, buf_len);
if (rc < 0) {
dev_err(dev, "Failed to upload config, retrying...\n");
continue;
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.