[PATCH v6 01/19] spi: spi-mem: allow specifying whether an op is DTR or not

From: Pratyush Yadav
Date: Wed May 20 2020 - 12:31:33 EST


Each phase is given a separate 'dtr' field so mixed protocols like
4S-4D-4D can be supported.

Signed-off-by: Pratyush Yadav <p.yadav@xxxxxx>
---
drivers/spi/spi-mem.c | 3 +++
include/linux/spi/spi-mem.h | 8 ++++++++
2 files changed, 11 insertions(+)

diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c
index 9a86cc27fcc0..93e255287ab9 100644
--- a/drivers/spi/spi-mem.c
+++ b/drivers/spi/spi-mem.c
@@ -156,6 +156,9 @@ bool spi_mem_default_supports_op(struct spi_mem *mem,
op->data.dir == SPI_MEM_DATA_OUT))
return false;

+ if (op->cmd.dtr || op->addr.dtr || op->dummy.dtr || op->data.dtr)
+ return false;
+
return true;
}
EXPORT_SYMBOL_GPL(spi_mem_default_supports_op);
diff --git a/include/linux/spi/spi-mem.h b/include/linux/spi/spi-mem.h
index af9ff2f0f1b2..e3dcb956bf61 100644
--- a/include/linux/spi/spi-mem.h
+++ b/include/linux/spi/spi-mem.h
@@ -71,9 +71,11 @@ enum spi_mem_data_dir {
* struct spi_mem_op - describes a SPI memory operation
* @cmd.buswidth: number of IO lines used to transmit the command
* @cmd.opcode: operation opcode
+ * @cmd.dtr: whether the command opcode should be sent in DTR mode or not
* @addr.nbytes: number of address bytes to send. Can be zero if the operation
* does not need to send an address
* @addr.buswidth: number of IO lines used to transmit the address cycles
+ * @addr.dtr: whether the address should be sent in DTR mode or not
* @addr.val: address value. This value is always sent MSB first on the bus.
* Note that only @addr.nbytes are taken into account in this
* address value, so users should make sure the value fits in the
@@ -81,7 +83,9 @@ enum spi_mem_data_dir {
* @dummy.nbytes: number of dummy bytes to send after an opcode or address. Can
* be zero if the operation does not require dummy bytes
* @dummy.buswidth: number of IO lanes used to transmit the dummy bytes
+ * @dummy.dtr: whether the dummy bytes should be sent in DTR mode or not
* @data.buswidth: number of IO lanes used to send/receive the data
+ * @data.dtr: whether the data should be sent in DTR mode or not
* @data.dir: direction of the transfer
* @data.nbytes: number of data bytes to send/receive. Can be zero if the
* operation does not involve transferring data
@@ -91,22 +95,26 @@ enum spi_mem_data_dir {
struct spi_mem_op {
struct {
u8 buswidth;
+ u8 dtr : 1;
u8 opcode;
} cmd;

struct {
u8 nbytes;
u8 buswidth;
+ u8 dtr : 1;
u64 val;
} addr;

struct {
u8 nbytes;
u8 buswidth;
+ u8 dtr : 1;
} dummy;

struct {
u8 buswidth;
+ u8 dtr : 1;
enum spi_mem_data_dir dir;
unsigned int nbytes;
union {
--
2.26.2