[PATCH 5.11 172/210] i2c: designware: Adjust bus_freq_hz when refuse high speed mode set

From: Greg Kroah-Hartman
Date: Mon Apr 12 2021 - 05:43:39 EST


From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

[ Upstream commit 5e729bc54bda705f64941008b018b4e41a4322bf ]

When hardware doesn't support High Speed Mode, we forget bus_freq_hz
timing adjustment. This makes the timings and real registers being
unsynchronized. Adjust bus_freq_hz when refuse high speed mode set.

Fixes: b6e67145f149 ("i2c: designware: Enable high speed mode")
Reported-by: "Song Bao Hua (Barry Song)" <song.bao.hua@xxxxxxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Reviewed-by: Barry Song <song.bao.hua@xxxxxxxxxxxxx>
Signed-off-by: Wolfram Sang <wsa@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/i2c/busses/i2c-designware-master.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index d6425ad6e6a3..2871cf2ee8b4 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -129,6 +129,7 @@ static int i2c_dw_set_timings_master(struct dw_i2c_dev *dev)
if ((comp_param1 & DW_IC_COMP_PARAM_1_SPEED_MODE_MASK)
!= DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH) {
dev_err(dev->dev, "High Speed not supported!\n");
+ t->bus_freq_hz = I2C_MAX_FAST_MODE_FREQ;
dev->master_cfg &= ~DW_IC_CON_SPEED_MASK;
dev->master_cfg |= DW_IC_CON_SPEED_FAST;
dev->hs_hcnt = 0;
--
2.30.2