> -----Original Message-----
> From: Jonathan Hunter <jonathanh@xxxxxxxxxx>
> Sent: 17 March 2022 14:25
> To: Krishna Yarlagadda <kyarlagadda@xxxxxxxxxx>; broonie@xxxxxxxxxx; thierry.reding@xxxxxxxxx; linux-spi@xxxxxxxxxxxxxxx; linux-
> tegra@xxxxxxxxxxxxxxx; Ashish Singhal <ashishsingha@xxxxxxxxxx>
> Cc: Sowjanya Komatineni <skomatineni@xxxxxxxxxx>; Laxman Dewangan <ldewangan@xxxxxxxxxx>; robh+dt@xxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH 2/3] spi: tegra210-quad: Add wait polling support
>
>
> On 17/03/2022 01:20, Krishna Yarlagadda wrote:
> > Controller can poll for wait state inserted by TPM device and
> > handle it.
> >
> > Signed-off-by: Krishna Yarlagadda <kyarlagadda@xxxxxxxxxx>
> > ---
> > drivers/spi/spi-tegra210-quad.c | 31 +++++++++++++++++++++++++++++++
> > 1 file changed, 31 insertions(+)
> >
> > diff --git a/drivers/spi/spi-tegra210-quad.c b/drivers/spi/spi-tegra210-quad.c
> > index a2e225e8f7f0..ecf171bfcdce 100644
> > --- a/drivers/spi/spi-tegra210-quad.c
> > +++ b/drivers/spi/spi-tegra210-quad.c
> > @@ -142,6 +142,7 @@
> >
> > #define QSPI_GLOBAL_CONFIG 0X1a4
> > #define QSPI_CMB_SEQ_EN BIT(0)
> > +#define QSPI_TPM_WAIT_POLL_EN BIT(1)
> >
> > #define QSPI_CMB_SEQ_ADDR 0x1a8
> > #define QSPI_ADDRESS_VALUE_SET(X) (((x) & 0xFFFF) << 0)
> > @@ -165,11 +166,13 @@ struct tegra_qspi_soc_data {
> > bool has_dma;
> > bool cmb_xfer_capable;
> > bool cs_count;
> > + bool has_wait_polling;
> > };
> >
> > struct tegra_qspi_client_data {
> > int tx_clk_tap_delay;
> > int rx_clk_tap_delay;
> > + bool wait_polling;
> > };
> >
> > struct tegra_qspi {
> > @@ -833,6 +836,11 @@ static u32 tegra_qspi_setup_transfer_one(struct spi_device *spi, struct spi_tran
> > else
> > command1 |= QSPI_CONTROL_MODE_0;
> >
> > + if (tqspi->soc_data->cmb_xfer_capable)
> > + command1 &= ~QSPI_CS_SW_HW;
> > + else
> > + command1 |= QSPI_CS_SW_HW;
> > +
> > if (spi->mode & SPI_CS_HIGH)
> > command1 |= QSPI_CS_SW_VAL;
> > else
> > @@ -917,6 +925,7 @@ static int tegra_qspi_start_transfer_one(struct spi_device *spi,
> >
> > static struct tegra_qspi_client_data *tegra_qspi_parse_cdata_dt(struct spi_device *spi)
> > {
> > + struct tegra_qspi *tqspi = spi_master_get_devdata(spi->master);
> > struct tegra_qspi_client_data *cdata;
> >
> > cdata = devm_kzalloc(&spi->dev, sizeof(*cdata), GFP_KERNEL);
> > @@ -927,6 +936,11 @@ static struct tegra_qspi_client_data *tegra_qspi_parse_cdata_dt(struct spi_devic
> > &cdata->tx_clk_tap_delay);
> > device_property_read_u32(&spi->dev, "nvidia,rx-clk-tap-delay",
> > &cdata->rx_clk_tap_delay);
> > + if (tqspi->soc_data->has_wait_polling)
> > + cdata->wait_polling = device_property_read_bool
> > + (&spi->dev,
> > + "nvidia,wait-polling");
> > +
>
>
> This looks odd. Why do we need this device-tree property if it is
> already specified in the SoC data?
Soc data specifies chip is capable of wait-polling.
Wait polling still has to be selected on slave devices that can support it.
I will add one line description for the properties in next version.
>
> Jon
>
> --
> nvpublic
