On Wed, Aug 16, 2023 at 3:19 AM Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx> wrote: > > On 15/08/2023 19:21, Hsin-Yi Wang wrote: > > On Tue, Aug 15, 2023 at 11:59 PM Michael Walle <michael@xxxxxxxx> wrote: > >> > >> Hi, > >> > >>> On gigadevice gd25lq64c, the quad mode is enabled after BFPT is parsed. > >>> According to datasheet[1], Quad enable (QE) bit needs to be set to 0 to > >>> use write protection (WP) pin. It also recommends setting default value of > >>> QE to 0 to avoid a potential short issue. > >> > >> So you are using either dual or single io mode. Why can't you use the device tree property spi-{tx,rx}-bus-width? > > > > I tried setting spi-tx-bus-width and spi-rx-bus-width to either 0 or 1 > > and WP still doesn't work. > > For this chip, quad_enable will be set to spi_nor_sr2_bit1_quad_enable > > (QER flag is BFPT_DWORD15_QER_SR2_BIT1_BUGGY)[1] > > > > spi_nor_write_sr_and_check() calls > > spi_nor_write_16bit_sr_and_check()[2] and the function sets QE bit if > > quad_enable is not NULL. > > > > [1] https://elixir.bootlin.com/linux/latest/source/drivers/mtd/spi-nor/sfdp.c#L575 > > [2] https://elixir.bootlin.com/linux/latest/source/drivers/mtd/spi-nor/core.c#L879 > > > > Setting spi-{tx,rx}-bus-width still falls to this function and cases. > > with tx/rx bus width = 2, how quad mode is still possible? IOW, why do > you need new property? You wrote here about driver, but I ask about > bindings. > This may be a bug in the driver that setting spi-{tx,rx}-bus-width still enables the QE bit. I proposed another method in the chip's fixup to deal with this issue instead of creating a new binding property. v2: https://lore.kernel.org/lkml/20230816104245.2676965-1-hsinyi@xxxxxxxxxxxx/ > Best regards, > Krzysztof >