[PATCH 5/7] spi: cadence-quadspi: Implement a simple supports_op hook

From: Pratyush Yadav
Date: Tue Dec 22 2020 - 13:45:22 EST


The default SPI MEM supports_op hook rejects DTR ops by default. Add a
simple supports_op hook that very closely imitates the SPI MEM one. It
will be extended in later commits to allow DTR ops.

Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx>
---
drivers/spi/spi-cadence-quadspi.c | 61 +++++++++++++++++++++++++++++++
1 file changed, 61 insertions(+)

diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index 376abef43530..1781d4e94ebd 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -1031,6 +1031,66 @@ static int cqspi_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op)
return ret;
}

+static int cqspi_check_buswidth_req(struct spi_mem *mem, u8 buswidth, bool tx)
+{
+ u32 mode = mem->spi->mode;
+
+ switch (buswidth) {
+ case 1:
+ return 0;
+
+ case 2:
+ if ((tx &&
+ (mode & (SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL))) ||
+ (!tx &&
+ (mode & (SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL))))
+ return 0;
+
+ break;
+
+ case 4:
+ if ((tx && (mode & (SPI_TX_QUAD | SPI_TX_OCTAL))) ||
+ (!tx && (mode & (SPI_RX_QUAD | SPI_RX_OCTAL))))
+ return 0;
+
+ break;
+
+ case 8:
+ if ((tx && (mode & SPI_TX_OCTAL)) ||
+ (!tx && (mode & SPI_RX_OCTAL)))
+ return 0;
+
+ break;
+
+ default:
+ break;
+ }
+
+ return -EOPNOTSUPP;
+}
+
+static bool cqspi_supports_mem_op(struct spi_mem *mem,
+ const struct spi_mem_op *op)
+{
+ if (cqspi_check_buswidth_req(mem, op->cmd.buswidth, true))
+ return false;
+
+ if (op->addr.nbytes &&
+ cqspi_check_buswidth_req(mem, op->addr.buswidth, true))
+ return false;
+
+ if (op->dummy.nbytes &&
+ cqspi_check_buswidth_req(mem, op->dummy.buswidth, true))
+ return false;
+
+ if (op->data.nbytes &&
+ cqspi_check_buswidth_req(mem, op->data.buswidth,
+ op->data.dir == SPI_MEM_DATA_OUT))
+ return false;
+
+ return true;
+}
+
static int cqspi_of_get_flash_pdata(struct platform_device *pdev,
struct cqspi_flash_pdata *f_pdata,
struct device_node *np)
@@ -1159,6 +1219,7 @@ static const char *cqspi_get_name(struct spi_mem *mem)
static const struct spi_controller_mem_ops cqspi_mem_ops = {
.exec_op = cqspi_exec_mem_op,
.get_name = cqspi_get_name,
+ .supports_op = cqspi_supports_mem_op,
};

static int cqspi_setup_flash(struct cqspi_st *cqspi)
--
2.28.0