From b16918a5fd87983d421a7e2241a1314e877c4ea2 Mon Sep 17 00:00:00 2001 From: Martyn Welch Date: Thu, 19 Oct 2017 16:51:44 +0100 Subject: hwmon: (da9052) Increase sample rate when using TSI The TSI channel, which is usually used for touchscreen support, but can be used as 4 general purpose ADCs. When used as a touchscreen interface the touchscreen driver switches the device into 1ms sampling mode (rather than the default 10ms economy mode) as recommended by the manufacturer. When using the TSI channels as a general purpose ADC we are currently not doing this and testing suggests that this can result in ADC timeouts: [ 5827.198289] da9052 spi2.0: timeout waiting for ADC conversion interrupt [ 5827.728293] da9052 spi2.0: timeout waiting for ADC conversion interrupt [ 5993.808335] da9052 spi2.0: timeout waiting for ADC conversion interrupt [ 5994.328441] da9052 spi2.0: timeout waiting for ADC conversion interrupt [ 5994.848291] da9052 spi2.0: timeout waiting for ADC conversion interrupt Switching to the 1ms timing resolves this issue. Fixes: 4f16cab19a3d5 ("hwmon: da9052: Add support for TSI channel") Signed-off-by: Martyn Welch Acked-by: Steve Twiss Signed-off-by: Guenter Roeck --- drivers/hwmon/da9052-hwmon.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/hwmon/da9052-hwmon.c') diff --git a/drivers/hwmon/da9052-hwmon.c b/drivers/hwmon/da9052-hwmon.c index 97a62f5b9ea4..a973eb6a2890 100644 --- a/drivers/hwmon/da9052-hwmon.c +++ b/drivers/hwmon/da9052-hwmon.c @@ -477,6 +477,11 @@ static int da9052_hwmon_probe(struct platform_device *pdev) /* disable touchscreen features */ da9052_reg_write(hwmon->da9052, DA9052_TSI_CONT_A_REG, 0x00); + /* Sample every 1ms */ + da9052_reg_update(hwmon->da9052, DA9052_ADC_CONT_REG, + DA9052_ADCCONT_ADCMODE, + DA9052_ADCCONT_ADCMODE); + err = da9052_request_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, "tsiready-irq", da9052_tsi_datardy_irq, hwmon); -- cgit v1.2.1