Re: [PATCH v8 3/6] spi: cadence-quadspi: Add multi-chipselect support for Intel LGM SoC

From: Vignesh Raghavendra
Date: Thu Nov 19 2020 - 07:57:24 EST




On 11/19/20 11:25 AM, Ramuthevar,Vadivel MuruganX wrote:
> From: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@xxxxxxxxxxxxxxx>
>
> Add multiple chipselect support for Intel LGM SoCs,
> currently QSPI-NOR and QSPI-NAND supported.
>
> Signed-off-by: Ramuthevar Vadivel Murugan <vadivel.muruganx.ramuthevar@xxxxxxxxxxxxxxx>
> ---
> drivers/spi/spi-cadence-quadspi.c | 15 +++++++++++++++
> 1 file changed, 15 insertions(+)
>
> diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
> index d12b765e87be..337778f75d5d 100644
> --- a/drivers/spi/spi-cadence-quadspi.c
> +++ b/drivers/spi/spi-cadence-quadspi.c
> @@ -38,6 +38,7 @@
>
> /* Capabilities */
> #define CQSPI_SUPPORTS_OCTAL BIT(0)
> +#define CQSPI_SUPPORTS_MULTI_CHIPSELECT BIT(1)
>
> struct cqspi_st;
>
> @@ -75,6 +76,7 @@ struct cqspi_st {
> bool is_decoded_cs;
> u32 fifo_depth;
> u32 fifo_width;
> + u32 num_chipselect;
> bool rclk_en;
> u32 trigger_address;
> u32 wr_delay;
> @@ -1049,6 +1051,7 @@ static int cqspi_of_get_flash_pdata(struct platform_device *pdev,
>
> static int cqspi_of_get_pdata(struct cqspi_st *cqspi)
> {
> + const struct cqspi_driver_platdata *ddata;

Unused variable?

> struct device *dev = &cqspi->pdev->dev;
> struct device_node *np = dev->of_node;
>
> @@ -1070,6 +1073,14 @@ static int cqspi_of_get_pdata(struct cqspi_st *cqspi)
> return -ENXIO;
> }
>
> + ddata = of_device_get_match_data(dev);
> + if (ddata->hwcaps_mask & CQSPI_SUPPORTS_MULTI_CHIPSELECT) {

I don't see a need for this flag... Controller by default supports
multiple CS.

> + if (of_property_read_u32(np, "num-cs", &cqspi->num_chipselect)) {
> + dev_err(dev, "couldn't determine number of cs\n");
> + return -ENXIO;
> + }
> + }
> +


Entire hunk can be replaced with:

if (of_property_read_u32(np, "num-cs", &cqspi->num_chipselect))
cqspi->num_chipselect = CQSPI_MAX_CHIPSELECT;


> cqspi->rclk_en = of_property_read_bool(np, "cdns,rclk-en");
>
> return 0;
> @@ -1302,6 +1313,9 @@ static int cqspi_probe(struct platform_device *pdev)
> cqspi->current_cs = -1;
> cqspi->sclk = 0;
>
> + if (ddata->hwcaps_mask & CQSPI_SUPPORTS_MULTI_CHIPSELECT)
> + master->num_chipselect = cqspi->num_chipselect;
> +

And then this becomes:
master->num_chipselect = cqspi->num_chipselect;

> ret = cqspi_setup_flash(cqspi);
> if (ret) {
> dev_err(dev, "failed to setup flash parameters %d\n", ret);
> @@ -1391,6 +1405,7 @@ static const struct cqspi_driver_platdata am654_ospi = {
> };
>
> static const struct cqspi_driver_platdata intel_lgm_qspi = {
> + .hwcaps_mask = CQSPI_SUPPORTS_MULTI_CHIPSELECT,
> .quirks = CQSPI_DISABLE_DAC_MODE,
> };
>
>