[PATCH v1] i3c/master: cmd_v1: Fix the rule for getting i3c mode

Billy Tsai billy_tsai at aspeedtech.com
Sun Aug 25 20:38:21 PDT 2024


Based on the I3C TCRI specification, the rules for determining the I3C
mode are as follows:
I3C SCL rate > 8MHz: use SDR0, with a maximum data rate of 8MHz
I3C SCL rate > 6MHz: use SDR1, with a maximum data rate of 6MHz
I3C SCL rate > 4MHz: use SDR2, with a maximum data rate of 4MHz
I3C SCL rate > 2MHz: use SDR3, with a maximum data rate of 2MHz
Otherwise, use SDR4

Signed-off-by: Billy Tsai <billy_tsai at aspeedtech.com>
Change-Id: If0e1100ca601c8a2f96ecbcc0f74e6fdb5e273df
---
 drivers/i3c/master/mipi-i3c-hci/cmd_v1.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/i3c/master/mipi-i3c-hci/cmd_v1.c b/drivers/i3c/master/mipi-i3c-hci/cmd_v1.c
index 638b054d6c92..dd636094b07f 100644
--- a/drivers/i3c/master/mipi-i3c-hci/cmd_v1.c
+++ b/drivers/i3c/master/mipi-i3c-hci/cmd_v1.c
@@ -123,17 +123,15 @@ static enum hci_cmd_mode get_i3c_mode(struct i3c_hci *hci)
 {
 	struct i3c_bus *bus = i3c_master_get_bus(&hci->master);
 
-	if (bus->scl_rate.i3c >= 12500000)
-		return MODE_I3C_SDR0;
 	if (bus->scl_rate.i3c > 8000000)
-		return MODE_I3C_SDR1;
+		return MODE_I3C_SDR0;
 	if (bus->scl_rate.i3c > 6000000)
-		return MODE_I3C_SDR2;
+		return MODE_I3C_SDR1;
 	if (bus->scl_rate.i3c > 4000000)
-		return MODE_I3C_SDR3;
+		return MODE_I3C_SDR2;
 	if (bus->scl_rate.i3c > 2000000)
-		return MODE_I3C_SDR4;
-	return MODE_I3C_Fm_FmP;
+		return MODE_I3C_SDR3;
+	return MODE_I3C_SDR4;
 }
 
 static enum hci_cmd_mode get_i2c_mode(struct i3c_hci *hci)
-- 
2.25.1




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