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* [PATCH v1 1/1] i2c: designware: Adjust bus_freq_hz when refuse high speed mode set
@ 2021-03-31 11:05 Andy Shevchenko
  2021-03-31 21:37 ` Song Bao Hua (Barry Song)
  2021-04-05 20:50 ` Wolfram Sang
  0 siblings, 2 replies; 4+ messages in thread
From: Andy Shevchenko @ 2021-03-31 11:05 UTC (permalink / raw)
  To: Andy Shevchenko, Serge Semin, linux-i2c, linux-kernel
  Cc: Jarkko Nikula, Mika Westerberg, wsa, Yicong Yang,
	Song Bao Hua (Barry Song)

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@hisilicon.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
 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 34bb4e21bcc3..9bfa06e31eec 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


^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2021-04-05 20:50 UTC | newest]

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2021-03-31 11:05 [PATCH v1 1/1] i2c: designware: Adjust bus_freq_hz when refuse high speed mode set Andy Shevchenko
2021-03-31 21:37 ` Song Bao Hua (Barry Song)
2021-04-05 11:55   ` Andy Shevchenko
2021-04-05 20:50 ` Wolfram Sang

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