Currently this driver uses a different way to implement the spi xfer,
by modifying some fields of two registers, which is incompatible with the
MTK's original SDK linux driver. This will cause the flash data being
damaged by the SDK driver.
This patch lets the mt7621_spi_set_cs() restore the original register
fields after cs deactivated.
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
The mt7621 spi controller supports continuous generic half-duplex spi
transaction. There is no need to cache xfer data at all.
To achieve this goal, the OPADDR register must be used as the first data
to be sent. And follows the eight generic DIDO registers. But one thing
different between OPADDR and DIDO registers is OPADDR has a reversed byte
order.
With this patch, any amount of data can be read/written in a single xfer
function call.
Reviewed-by: Stefan Roese <sr@denx.de>
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
This patch lets the spi driver to use clock provided by the clk driver
since the new clk-mt7628 driver provides accurate sys clock frequency.
Signed-off-by: Weijie Gao <weijie.gao@mediatek.com>
This patch adds the SPI driver for the MediaTek MT7688 SoC (and
derivates). Its been tested on the LinkIt Smart 7688 and the Gardena
Smart Gateway with and SPI NOR on CS0 and on the Gardena Smart
Gateway additionally with an SPI NAND on CS1.
Note that the SPI controller only supports a max transfer size of 32
bytes. This driver implementes a workaround to enable bigger xfer
sizes to speed up the transfer especially for the SPI NAND support.
Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Jagan Teki <jagan@openedev.com>
Cc: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Cc: Piotr Dymacz <pepe2k@gmail.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
