Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

i3c/master: cmd_v1: Fix the rule for getting i3c mode

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

Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
Link: https://lore.kernel.org/r/20240826033821.175591-1-billy_tsai@aspeedtech.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

authored by

Billy Tsai and committed by
Alexandre Belloni
061dd21c 133f67be

+5 -7
+5 -7
drivers/i3c/master/mipi-i3c-hci/cmd_v1.c
··· 123 123 { 124 124 struct i3c_bus *bus = i3c_master_get_bus(&hci->master); 125 125 126 - if (bus->scl_rate.i3c >= 12500000) 127 - return MODE_I3C_SDR0; 128 126 if (bus->scl_rate.i3c > 8000000) 129 - return MODE_I3C_SDR1; 127 + return MODE_I3C_SDR0; 130 128 if (bus->scl_rate.i3c > 6000000) 131 - return MODE_I3C_SDR2; 129 + return MODE_I3C_SDR1; 132 130 if (bus->scl_rate.i3c > 4000000) 133 - return MODE_I3C_SDR3; 131 + return MODE_I3C_SDR2; 134 132 if (bus->scl_rate.i3c > 2000000) 135 - return MODE_I3C_SDR4; 136 - return MODE_I3C_Fm_FmP; 133 + return MODE_I3C_SDR3; 134 + return MODE_I3C_SDR4; 137 135 } 138 136 139 137 static enum hci_cmd_mode get_i2c_mode(struct i3c_hci *hci)