From: William Breathitt Gray Date: Wed, 5 Mar 2025 10:01:19 +0000 (+0900) Subject: counter: microchip-tcb-capture: Fix undefined counter channel state on probe X-Git-Tag: v6.1.133~12 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=79aafdf639857aaf4932d1e9d5ed1cc40ca33b8b;p=thirdparty%2Fkernel%2Fstable.git 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 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c index c7af13aca36cf..2f631729a870b 100644 --- a/drivers/counter/microchip-tcb-capture.c +++ b/drivers/counter/microchip-tcb-capture.c @@ -369,6 +369,25 @@ 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);