mtd: spi-nor: fix page program issue when using spi-mem driver

Some SPI controllers can't write nor->page_size bytes in a single step
because their TX FIFO is too small, but when that happens we should
make sure a WRITE_EN command before each write access and READ_SR command
after each write access is issued.

We should allow nor->write() to return a size that is smaller than the
requested write size to gracefully handle this case.

Also, the spi_nor_write_data() should return the actual number of bytes
that were written during the spi_mem_exec_op() operation.

This patch is a combination of two commits backported from kernel:

  commit 630d6bd8a3b4 ("mtd: spi-nor: Support controllers with limit ...")
  commit 3baa8ec88c2f ("mtd: devices: m25p80: Make sure WRITE_EN is ...")

Cc: Vignesh R <vigneshr@ti.com>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
Acked-by: Vignesh R <vigneshr@ti.com>
Tested-by: Shyam Saini <shyam.saini@amarulasolutions.com> # microzed
Acked-by: Jagan Teki <jagan@amarulasolutions.com>
This commit is contained in:
Weijie Gao 2019-04-26 17:22:19 +08:00 committed by Jagan Teki
parent b4ee6daad7
commit 60e2bf4678

View file

@ -116,7 +116,6 @@ static ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
SPI_MEM_OP_ADDR(nor->addr_width, to, 1),
SPI_MEM_OP_NO_DUMMY,
SPI_MEM_OP_DATA_OUT(len, buf, 1));
size_t remaining = len;
int ret;
/* get transfer protocols. */
@ -127,22 +126,16 @@ static ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len,
if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second)
op.addr.nbytes = 0;
while (remaining) {
op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX;
ret = spi_mem_adjust_op_size(nor->spi, &op);
if (ret)
return ret;
ret = spi_mem_adjust_op_size(nor->spi, &op);
if (ret)
return ret;
op.data.nbytes = len < op.data.nbytes ? len : op.data.nbytes;
ret = spi_mem_exec_op(nor->spi, &op);
if (ret)
return ret;
ret = spi_mem_exec_op(nor->spi, &op);
if (ret)
return ret;
op.addr.val += op.data.nbytes;
remaining -= op.data.nbytes;
op.data.buf.out += op.data.nbytes;
}
return len;
return op.data.nbytes;
}
/*
@ -1101,10 +1094,6 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len,
goto write_err;
*retlen += written;
i += written;
if (written != page_remain) {
ret = -EIO;
goto write_err;
}
}
write_err: