From b7ad6be2ee67b12cba31d30deb34beab19acac57 Mon Sep 17 00:00:00 2001 From: Sergei Shtylyov Date: Wed, 19 Feb 2020 00:21:00 +0300 Subject: [PATCH] mtd: spi-nor: split spi_nor_spimem_xfer_data() 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 Signed-off-by: Tudor Ambarus --- drivers/mtd/spi-nor/spi-nor.c | 87 ++++++++++++++++++++++++------------------- 1 file changed, 48 insertions(+), 39 deletions(-) diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index b5ef17b..1ce9784 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -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; + return false; +} - ret = spi_mem_exec_op(nor->spimem, op); - if (ret) - return ret; +/** + * 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; - if (usebouncebuf && op->data.dir == SPI_MEM_DATA_IN) - memcpy(rdbuf, nor->bouncebuf, op->data.nbytes); + error = spi_mem_adjust_op_size(nor->spimem, op); + if (error) + return error; - return op->data.nbytes; + return spi_mem_exec_op(nor->spimem, op); } /** @@ -315,6 +305,8 @@ static ssize_t spi_nor_spimem_read_data(struct spi_nor *nor, loff_t from, 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(struct spi_nor *nor, loff_t from, /* 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(struct spi_nor *nor, loff_t to, 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(struct spi_nor *nor, loff_t to, 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; } /** -- 2.7.4