===================================================================
@@ -246,55 +246,45 @@ struct flash_info {
#define JEDEC_MFR(info) ((info)->id[0])
/**
- * spi_nor_spimem_xfer_data() - helper function to read/write data to
- * flash's memory region
+ * spi_nor_spimem_bounce() - check if a bounce buffer is needed for the data
+ * transfer
* @nor: pointer to 'struct spi_nor'
* @op: pointer to 'struct spi_mem_op' template for transfer
*
- * Return: number of bytes transferred on success, -errno otherwise
+ * If we have to use the bounce buffer, the data field in @op will be updated.
+ *
+ * Return: true if the bounce buffer is needed, false if not
*/
-static ssize_t spi_nor_spimem_xfer_data(struct spi_nor *nor,
- struct spi_mem_op *op)
+static bool spi_nor_spimem_bounce(struct spi_nor *nor, struct spi_mem_op *op)
{
- bool usebouncebuf = false;
- void *rdbuf = NULL;
- const void *buf;
- int ret;
-
- if (op->data.dir == SPI_MEM_DATA_IN)
- buf = op->data.buf.in;
- else
- buf = op->data.buf.out;
-
- if (object_is_on_stack(buf) || !virt_addr_valid(buf))
- usebouncebuf = true;
-
- if (usebouncebuf) {
+ /* op->data.buf.in occupies the same memory as op->data.buf.out */
+ if (object_is_on_stack(op->data.buf.in) ||
+ !virt_addr_valid(op->data.buf.in)) {
if (op->data.nbytes > nor->bouncebuf_size)
op->data.nbytes = nor->bouncebuf_size;
-
- if (op->data.dir == SPI_MEM_DATA_IN) {
- rdbuf = op->data.buf.in;
- op->data.buf.in = nor->bouncebuf;
- } else {
- op->data.buf.out = nor->bouncebuf;
- memcpy(nor->bouncebuf, buf,
- op->data.nbytes);
- }
+ op->data.buf.in = nor->bouncebuf;
+ return true;
}
- ret = spi_mem_adjust_op_size(nor->spimem, op);
- if (ret)
- return ret;
-
- ret = spi_mem_exec_op(nor->spimem, op);
- if (ret)
- return ret;
+ return false;
+}
- if (usebouncebuf && op->data.dir == SPI_MEM_DATA_IN)
- memcpy(rdbuf, nor->bouncebuf, op->data.nbytes);
+/**
+ * spi_nor_spimem_exec_op() - execute a memory operation
+ * @nor: pointer to 'struct spi_nor'
+ * @op: pointer to 'struct spi_mem_op' template for transfer
+ *
+ * Return: 0 on success, -error otherwise.
+ */
+static int spi_nor_spimem_exec_op(struct spi_nor *nor, struct spi_mem_op *op)
+{
+ int error;
- return op->data.nbytes;
+ error = spi_mem_adjust_op_size(nor->spimem, op);
+ if (error)
+ return error;
+
+ return spi_mem_exec_op(nor->spimem, op);
}
/**
@@ -315,6 +305,8 @@ static ssize_t spi_nor_spimem_read_data(
SPI_MEM_OP_ADDR(nor->addr_width, from, 1),
SPI_MEM_OP_DUMMY(nor->read_dummy, 1),
SPI_MEM_OP_DATA_IN(len, buf, 1));
+ bool usebouncebuf;
+ int error;
/* get transfer protocols. */
op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->read_proto);
@@ -325,7 +317,16 @@ static ssize_t spi_nor_spimem_read_data(
/* convert the dummy cycles to the number of bytes */
op.dummy.nbytes = (nor->read_dummy * op.dummy.buswidth) / 8;
- return spi_nor_spimem_xfer_data(nor, &op);
+ usebouncebuf = spi_nor_spimem_bounce(nor, &op);
+
+ error = spi_nor_spimem_exec_op(nor, &op);
+ if (error)
+ return error;
+
+ if (usebouncebuf)
+ memcpy(buf, op.data.buf.in, op.data.nbytes);
+
+ return op.data.nbytes;
}
/**
@@ -364,6 +365,7 @@ static ssize_t spi_nor_spimem_write_data
SPI_MEM_OP_ADDR(nor->addr_width, to, 1),
SPI_MEM_OP_NO_DUMMY,
SPI_MEM_OP_DATA_OUT(len, buf, 1));
+ int error;
op.cmd.buswidth = spi_nor_get_protocol_inst_nbits(nor->write_proto);
op.addr.buswidth = spi_nor_get_protocol_addr_nbits(nor->write_proto);
@@ -372,7 +374,14 @@ static ssize_t spi_nor_spimem_write_data
if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
op.addr.nbytes = 0;
- return spi_nor_spimem_xfer_data(nor, &op);
+ if (spi_nor_spimem_bounce(nor, &op))
+ memcpy(nor->bouncebuf, buf, op.data.nbytes);
+
+ error = spi_nor_spimem_exec_op(nor, &op);
+ if (error)
+ return error;
+
+ return op.data.nbytes;
}
/**
spi_nor_spimem_xfer_data() being a helper function for the data reads/ writes contains 3 fragments that depend on the data direction; and I'm going to add another one to call the SPI dirmap API... I think this function should be split so that the common fragments are put into 2 functions, spi_nor_spimem_bounce() and spi_nor_spimem_exec_op() called from spi_nor_spimem_{read|write}_data(), and the data direction dependent bits moved back into those read/write functions -- that way we would be able to avoid *goto*s otherwise needed in the next patch adding the SPI dirmap support... Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> --- Changes in version 5: - removed the 'usebouncebuf' local variable from spi_nor_spimem_write_data(); - refreshed the patch. Changes in version 4: - new patch. drivers/mtd/spi-nor/spi-nor.c | 89 +++++++++++++++++++++++------------------- 1 file changed, 49 insertions(+), 40 deletions(-)