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i2c: qcom-cci: Switch msm8953 to the CCI v2 timing/rate config

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The msm8953 CCI timing table is internally inconsistent. Its Standard
and Fast timings match v1/v1.5, which are calibrated for a 19.2 MHz CCI
clock, but its Fast+ timings are essentially the 'v2' values, which are
calibrated for 37.5 MHz. Since all masters share a single CCI clock,
no single rate can satisfy all three modes with the current table, and
the DT assigns 19.2 MHz, so Fast+ timings are wrong.

The msm8953 CCI is the same hardware version as msm8996/sdm630, which
already use the cci_v2_data config (37.5 MHz). 37.5 MHz is supported by
the msm8953 CCI RCG, so reuse cci_v2_data for msm8953 as well and drop
the redundant, inconsistent standalone table. This makes all three I2C
modes self-consistent under a single clock rate.

Note this requires the CCI clock to run at 37.5 MHz, the driver selects
and enforces the proper rate in following patches.

Signed-off-by: Loic Poulain <loic.poulain@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
Link: https://patch.msgid.link/20260929-cci-clk-fix-v6-1-62a268cccb0f@oss.qualcomm.com
This commit is contained in:
Loic Poulain 2026-09-29 14:25:45 +02:00 committed by Andi Shyti
parent 8027cc6835
commit d07c7775ca
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GPG Key ID: DA78056626D32D6E
1 changed files with 1 additions and 46 deletions
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47
drivers/i2c/busses/i2c-qcom-cci.c
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@ -753,54 +753,9 @@ static const struct cci_data cci_v2_data = {
},
};
static const struct cci_data cci_msm8953_data = {
.num_masters = 2,
.queue_size = { 64, 16 },
.quirks = {
.max_write_len = 11,
.max_read_len = 12,
},
.params[I2C_MODE_STANDARD] = {
.thigh = 78,
.tlow = 114,
.tsu_sto = 28,
.tsu_sta = 28,
.thd_dat = 10,
.thd_sta = 77,
.tbuf = 118,
.scl_stretch_en = 0,
.trdhld = 6,
.tsp = 1
},
.params[I2C_MODE_FAST] = {
.thigh = 20,
.tlow = 28,
.tsu_sto = 21,
.tsu_sta = 21,
.thd_dat = 13,
.thd_sta = 18,
.tbuf = 32,
.scl_stretch_en = 0,
.trdhld = 6,
.tsp = 3
},
.params[I2C_MODE_FAST_PLUS] = {
.thigh = 16,
.tlow = 22,
.tsu_sto = 17,
.tsu_sta = 18,
.thd_dat = 16,
.thd_sta = 15,
.tbuf = 19,
.scl_stretch_en = 1,
.trdhld = 3,
.tsp = 3
},
};
static const struct of_device_id cci_dt_match[] = {
{ .compatible = "qcom,msm8226-cci", .data = &cci_v1_data},
{ .compatible = "qcom,msm8953-cci", .data = &cci_msm8953_data},
{ .compatible = "qcom,msm8953-cci", .data = &cci_v2_data},
{ .compatible = "qcom,msm8974-cci", .data = &cci_v1_5_data},
{ .compatible = "qcom,msm8996-cci", .data = &cci_v2_data},