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| author | William Breathitt Gray <wbg@kernel.org> | 2025-03-05 19:01:19 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-04-07 10:06:37 +0200 |
| commit | 52eed361c25087ceabd3c0feb6cb820593611336 (patch) | |
| tree | e6b1d96e9512350b9e7ed4e0fb4ea6339509680e | |
| parent | fa15592e9d92a32a1377f2707ba0e0b7f962ac87 (diff) | |
| download | linux-52eed361c25087ceabd3c0feb6cb820593611336.tar.gz linux-52eed361c25087ceabd3c0feb6cb820593611336.tar.bz2 linux-52eed361c25087ceabd3c0feb6cb820593611336.zip | |
counter: microchip-tcb-capture: Fix undefined counter channel state on probe
commit c0c9c73434666dc99ee156b25e7e722150bee001 upstream.
Hardware initialize of the timer counter channel does not occur on probe
thus leaving the Count in an undefined state until the first
function_write() callback is executed. Fix this by performing the proper
hardware initialization during probe.
Fixes: 106b104137fd ("counter: Add microchip TCB capture counter")
Reported-by: Csókás Bence <csokas.bence@prolan.hu>
Closes: https://lore.kernel.org/all/bfa70e78-3cc3-4295-820b-3925c26135cb@prolan.hu/
Link: https://lore.kernel.org/r/20250305-preset-capture-mode-microchip-tcb-capture-v1-1-632c95c6421e@kernel.org
Signed-off-by: William Breathitt Gray <wbg@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/counter/microchip-tcb-capture.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c index b3e615cbd2ca..461f57f66631 100644 --- a/drivers/counter/microchip-tcb-capture.c +++ b/drivers/counter/microchip-tcb-capture.c @@ -368,6 +368,25 @@ static int mchp_tc_probe(struct platform_device *pdev) channel); } + /* Disable Quadrature Decoder and position measure */ + ret = regmap_update_bits(regmap, ATMEL_TC_BMR, ATMEL_TC_QDEN | ATMEL_TC_POSEN, 0); + if (ret) + return ret; + + /* Setup the period capture mode */ + ret = regmap_update_bits(regmap, ATMEL_TC_REG(priv->channel[0], CMR), + ATMEL_TC_WAVE | ATMEL_TC_ABETRG | ATMEL_TC_CMR_MASK | + ATMEL_TC_TCCLKS, + ATMEL_TC_CMR_MASK); + if (ret) + return ret; + + /* Enable clock and trigger counter */ + ret = regmap_write(regmap, ATMEL_TC_REG(priv->channel[0], CCR), + ATMEL_TC_CLKEN | ATMEL_TC_SWTRG); + if (ret) + return ret; + priv->tc_cfg = tcb_config; priv->regmap = regmap; counter->name = dev_name(&pdev->dev); |