[PATCH v7 2/5] i3c: master: svc: Replace bool rnw with union for HDR support

Frank Li
2025-10-27T20:08:57Z

Replace the bool rnw field with a union in preparation for adding HDR
support. HDR uses a cmd field instead of the rnw bit to indicate read or
write direction.

Add helper function svc_cmd_is_read() to check transfer direction.

Add a local variable 'rnw' in svc_i3c_master_priv_xfers() to avoid
repeatedly accessing xfers[i].rnw.

No functional change.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
change in v7
none
---
drivers/i3c/master/svc-i3c-master.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 9641e66a4e5f2da3bd84b30fa741e5e19d87465d..7c516e05d0a1a118479ee3d8ea8ae37ae19fea57 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -165,7 +165,11 @@

struct svc_i3c_cmd {
u8 addr;
- bool rnw;
+ union {
+ bool rnw;
+ u8 cmd;
+ u32 rnw_cmd;
+ };
u8 *in;
const void *out;
unsigned int len;
@@ -383,6 +387,11 @@ svc_i3c_master_dev_from_addr(struct svc_i3c_master *master,
return master->descs[i];
}

+static bool svc_cmd_is_read(u32 rnw_cmd, u32 type)
+{
+ return rnw_cmd;
+}
+
static void svc_i3c_master_emit_stop(struct svc_i3c_master *master)
{
writel(SVC_I3C_MCTRL_REQUEST_STOP, master->regs + SVC_I3C_MCTRL);
@@ -1293,10 +1302,11 @@ static int svc_i3c_master_write(struct svc_i3c_master *master,
}

static int svc_i3c_master_xfer(struct svc_i3c_master *master,
- bool rnw, unsigned int xfer_type, u8 addr,
+ u32 rnw_cmd, unsigned int xfer_type, u8 addr,
u8 *in, const u8 *out, unsigned int xfer_len,
unsigned int *actual_len, bool continued, bool repeat_start)
{
+ bool rnw = svc_cmd_is_read(rnw_cmd, xfer_type);
int retry = repeat_start ? 1 : 2;
u32 reg;
int ret;
@@ -1484,7 +1494,7 @@ static void svc_i3c_master_start_xfer_locked(struct svc_i3c_master *master)
for (i = 0; i < xfer->ncmds; i++) {
struct svc_i3c_cmd *cmd = &xfer->cmds[i];

- ret = svc_i3c_master_xfer(master, cmd->rnw, xfer->type,
+ ret = svc_i3c_master_xfer(master, cmd->rnw_cmd, xfer->type,
cmd->addr, cmd->in, cmd->out,
cmd->len, &cmd->actual_len,
cmd->continued, i > 0);
@@ -1677,14 +1687,15 @@ static int svc_i3c_master_priv_xfers(struct i3c_dev_desc *dev,

for (i = 0; i < nxfers; i++) {
struct svc_i3c_cmd *cmd = &xfer->cmds[i];
+ bool rnw = xfers[i].rnw;

cmd->xfer = &xfers[i];
cmd->addr = master->addrs[data->index];
- cmd->rnw = xfers[i].rnw;
- cmd->in = xfers[i].rnw ? xfers[i].data.in : NULL;
- cmd->out = xfers[i].rnw ? NULL : xfers[i].data.out;
+ cmd->rnw = rnw;
+ cmd->in = rnw ? xfers[i].data.in : NULL;
+ cmd->out = rnw ? NULL : xfers[i].data.out;
cmd->len = xfers[i].len;
- cmd->actual_len = xfers[i].rnw ? xfers[i].len : 0;
+ cmd->actual_len = rnw ? xfers[i].len : 0;
cmd->continued = (i + 1) < nxfers;
}

--
2.34.1