sf: Respect maximum SPI write size
Some SPI flash controllers (e.g. Intel ICH) have a limit on the number of
bytes that can be in a write transaction. Support this by breaking the
writes into multiple transactions.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
index 17f3d3c..b82011d 100644
--- a/drivers/mtd/spi/spi_flash.c
+++ b/drivers/mtd/spi/spi_flash.c
@@ -87,6 +87,9 @@
for (actual = 0; actual < len; actual += chunk_len) {
chunk_len = min(len - actual, page_size - byte_addr);
+ if (flash->spi->max_write_size)
+ chunk_len = min(chunk_len, flash->spi->max_write_size);
+
cmd[1] = page_addr >> 8;
cmd[2] = page_addr;
cmd[3] = byte_addr;
@@ -111,8 +114,11 @@
if (ret)
break;
- page_addr++;
- byte_addr = 0;
+ byte_addr += chunk_len;
+ if (byte_addr == page_size) {
+ page_addr++;
+ byte_addr = 0;
+ }
}
debug("SF: program %s %zu bytes @ %#x\n",