spi: ich: Limit slave->max_read_size
Since commit 43c145b8b3ee ("spi: ich: Correct max-size bug in ich_spi_adjust_size()")
(in v2020.04-rc1), SPI flash read no longer works with ICH SPI controller
in software sequencer mode.
ICH controller can only transfer a small number of bytes at once.
Before commit 43c145b8b3ee, the logic happens to make sure data.nbytes
is limited to slave->max_write_size but after commit 43c145b8b3ee
data.nbytes is no longer limited because slave->max_read_size is not
initialized with a valid number.
Fixes: 43c145b8b3ee ("spi: ich: Correct max-size bug in ich_spi_adjust_size()")
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/spi/ich.c b/drivers/spi/ich.c
index 3d49c22..08d54e8 100644
--- a/drivers/spi/ich.c
+++ b/drivers/spi/ich.c
@@ -918,12 +918,14 @@
struct spi_slave *slave = dev_get_parent_priv(dev);
/*
- * Yes this controller can only write a small number of bytes at
+ * Yes this controller can only transfer a small number of bytes at
* once! The limit is typically 64 bytes. For hardware sequencing a
* a loop is used to get around this.
*/
- if (!plat->hwseq)
+ if (!plat->hwseq) {
+ slave->max_read_size = priv->databytes;
slave->max_write_size = priv->databytes;
+ }
/*
* ICH 7 SPI controller only supports array read command
* and byte program command for SST flash