[PATCH v4 1/4] i3c: Standardize defines for specification parameters
Wolfram Sang
wsa+renesas at sang-engineering.com
Tue Jul 22 12:07:43 PDT 2025
Align existing defines to follow the consistent pattern:
I3C_BUS_<PARAM>_<MAX|MIN|TYP>_<UNIT>. Prepare the codebase for adding
new parameters and help avoid duplication.
Signed-off-by: Wolfram Sang <wsa+renesas at sang-engineering.com>
---
Changes since v3:
* Reworded commit message
* added version of spec and chapter number to the comment
I added the chapter number to the main comment because it is applicable
for all the values here and the next patch. I thought it doesn't make
sense to repeat it all over for each value.
drivers/i3c/master.c | 12 ++++++------
drivers/i3c/master/dw-i3c-master.c | 4 ++--
include/linux/i3c/master.h | 9 +++++----
3 files changed, 13 insertions(+), 12 deletions(-)
diff --git a/drivers/i3c/master.c b/drivers/i3c/master.c
index ffb734d378e2..6a2594dc29e6 100644
--- a/drivers/i3c/master.c
+++ b/drivers/i3c/master.c
@@ -728,12 +728,12 @@ static int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode,
switch (i3cbus->mode) {
case I3C_BUS_MODE_PURE:
if (!i3cbus->scl_rate.i3c)
- i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
+ i3cbus->scl_rate.i3c = I3C_BUS_I3C_SCL_TYP_RATE;
break;
case I3C_BUS_MODE_MIXED_FAST:
case I3C_BUS_MODE_MIXED_LIMITED:
if (!i3cbus->scl_rate.i3c)
- i3cbus->scl_rate.i3c = I3C_BUS_TYP_I3C_SCL_RATE;
+ i3cbus->scl_rate.i3c = I3C_BUS_I3C_SCL_TYP_RATE;
if (!i3cbus->scl_rate.i2c)
i3cbus->scl_rate.i2c = max_i2c_scl_rate;
break;
@@ -755,8 +755,8 @@ static int i3c_bus_set_mode(struct i3c_bus *i3cbus, enum i3c_bus_mode mode,
* I3C/I2C frequency may have been overridden, check that user-provided
* values are not exceeding max possible frequency.
*/
- if (i3cbus->scl_rate.i3c > I3C_BUS_MAX_I3C_SCL_RATE ||
- i3cbus->scl_rate.i2c > I3C_BUS_I2C_FM_PLUS_SCL_RATE)
+ if (i3cbus->scl_rate.i3c > I3C_BUS_I3C_SCL_MAX_RATE ||
+ i3cbus->scl_rate.i2c > I3C_BUS_I2C_FM_PLUS_SCL_MAX_RATE)
return -EINVAL;
return 0;
@@ -2786,7 +2786,7 @@ int i3c_master_register(struct i3c_master_controller *master,
const struct i3c_master_controller_ops *ops,
bool secondary)
{
- unsigned long i2c_scl_rate = I3C_BUS_I2C_FM_PLUS_SCL_RATE;
+ unsigned long i2c_scl_rate = I3C_BUS_I2C_FM_PLUS_SCL_MAX_RATE;
struct i3c_bus *i3cbus = i3c_master_get_bus(master);
enum i3c_bus_mode mode = I3C_BUS_MODE_PURE;
struct i2c_dev_boardinfo *i2cbi;
@@ -2845,7 +2845,7 @@ int i3c_master_register(struct i3c_master_controller *master,
}
if (i2cbi->lvr & I3C_LVR_I2C_FM_MODE)
- i2c_scl_rate = I3C_BUS_I2C_FM_SCL_RATE;
+ i2c_scl_rate = I3C_BUS_I2C_FM_SCL_MAX_RATE;
}
ret = i3c_bus_set_mode(i3cbus, mode, i2c_scl_rate);
diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index 91429d94a866..dc234efa046d 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -622,14 +622,14 @@ static int dw_i2c_clk_cfg(struct dw_i3c_master *master)
core_period = DIV_ROUND_UP(1000000000, core_rate);
lcnt = DIV_ROUND_UP(I3C_BUS_I2C_FMP_TLOW_MIN_NS, core_period);
- hcnt = DIV_ROUND_UP(core_rate, I3C_BUS_I2C_FM_PLUS_SCL_RATE) - lcnt;
+ hcnt = DIV_ROUND_UP(core_rate, I3C_BUS_I2C_FM_PLUS_SCL_MAX_RATE) - lcnt;
scl_timing = SCL_I2C_FMP_TIMING_HCNT(hcnt) |
SCL_I2C_FMP_TIMING_LCNT(lcnt);
writel(scl_timing, master->regs + SCL_I2C_FMP_TIMING);
master->i2c_fmp_timing = scl_timing;
lcnt = DIV_ROUND_UP(I3C_BUS_I2C_FM_TLOW_MIN_NS, core_period);
- hcnt = DIV_ROUND_UP(core_rate, I3C_BUS_I2C_FM_SCL_RATE) - lcnt;
+ hcnt = DIV_ROUND_UP(core_rate, I3C_BUS_I2C_FM_SCL_MAX_RATE) - lcnt;
scl_timing = SCL_I2C_FM_TIMING_HCNT(hcnt) |
SCL_I2C_FM_TIMING_LCNT(lcnt);
writel(scl_timing, master->regs + SCL_I2C_FM_TIMING);
diff --git a/include/linux/i3c/master.h b/include/linux/i3c/master.h
index c67922ece617..7dfcbe530515 100644
--- a/include/linux/i3c/master.h
+++ b/include/linux/i3c/master.h
@@ -249,10 +249,11 @@ struct i3c_device {
*/
#define I3C_BUS_MAX_DEVS 11
-#define I3C_BUS_MAX_I3C_SCL_RATE 12900000
-#define I3C_BUS_TYP_I3C_SCL_RATE 12500000
-#define I3C_BUS_I2C_FM_PLUS_SCL_RATE 1000000
-#define I3C_BUS_I2C_FM_SCL_RATE 400000
+/* Taken from the I3C Spec V1.1.1, chapter 6.2. "Timing specification" */
+#define I3C_BUS_I2C_FM_PLUS_SCL_MAX_RATE 1000000
+#define I3C_BUS_I2C_FM_SCL_MAX_RATE 400000
+#define I3C_BUS_I3C_SCL_MAX_RATE 12900000
+#define I3C_BUS_I3C_SCL_TYP_RATE 12500000
#define I3C_BUS_TLOW_OD_MIN_NS 200
/**
--
2.47.2
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