We need that to adjust the len of the 2nd transfer (called data in spi-mem) if it's too long to fit in a SPI message or SPI transfer.
Fixes: c36ff266dc82 ("spi: Extend the core to ease integration of SPI memory controllers") Cc: stable@vger.kernel.org Signed-off-by: Chuanhua Han chuanhua.han@nxp.com Suggested-by: Boris Brezillon boris.brezillon@bootlin.com --- Changes in v5: -Add the validation check after the op->data.nbytes assignment -Assign the "len" variable after defining it -Remove the brackets on both sides of "opt-> data.nbytes" Changes in v4: -Rename variable name "opcode_addr_dummy_sum" to "len". -The comparison of "spi_max_message_size(mem->spi)" and "len" was removed. -Adjust their order when comparing the sizes of "spi_max_message_size(mem->spi)" and "len" -Changing the "unsigned long" type in the code to "size_t" Changes in v3: -Rename variable name "val" to "opcode_addr_dummy_sum". -Place the legitimacy of the transfer size(i.e., "spi_max_message_size(mem->spi)" and -"opcode_addr_dummy_sum") into "if (! ctlr - > mem_ops | |! ctlr-> mem_ops->exec_op) {" structure and add "spi_max_transfer_size(mem->spi) and opcode_addr_dummy_sum". -Adjust the formatting alignment of the code. -"(unsigned long)op->data.nbytes" was modified to "(unsigned long)(op->data.nbytes)". Changes in v2: -Place the adjusted transfer bytes code in spi_mem_adjust_op_size() and check spi_max_message_size(mem->spi) value before subtracting opcode, addr and dummy bytes. -Change the code from fsl-espi controller to generic code(The adjustment of spi transmission length was originally modified in the "drivers/spi/spi-fsl-espi.c" file, and now the adjustment of transfer length is made in the "drivers/spi/spi-mem.c" file)
drivers/spi/spi-mem.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index 990770d..6184fa1 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -328,10 +328,26 @@ EXPORT_SYMBOL_GPL(spi_mem_exec_op); int spi_mem_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op) { struct spi_controller *ctlr = mem->spi->controller; + size_t len; + + len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
if (ctlr->mem_ops && ctlr->mem_ops->adjust_op_size) return ctlr->mem_ops->adjust_op_size(mem, op);
+ if (!ctlr->mem_ops || !ctlr->mem_ops->exec_op) { + if (len > spi_max_transfer_size(mem->spi)) + return -EINVAL; + + op->data.nbytes = min3((size_t)op->data.nbytes, + spi_max_transfer_size(mem->spi), + spi_max_message_size(mem->spi) - + len); + + if (!op->data.nbytes) + return -EINVAL; + } + return 0; } EXPORT_SYMBOL_GPL(spi_mem_adjust_op_size);