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-rw-r--r--drivers/iio/adc/axp288_adc.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c
index adc9cf7a075d..8ea2aed6d6f5 100644
--- a/drivers/iio/adc/axp288_adc.c
+++ b/drivers/iio/adc/axp288_adc.c
@@ -7,6 +7,7 @@
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
+#include <linux/dmi.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
@@ -25,6 +26,11 @@
#define AXP288_ADC_EN_MASK 0xF0
#define AXP288_ADC_TS_ENABLE 0x01
+#define AXP288_ADC_TS_BIAS_MASK GENMASK(5, 4)
+#define AXP288_ADC_TS_BIAS_20UA (0 << 4)
+#define AXP288_ADC_TS_BIAS_40UA (1 << 4)
+#define AXP288_ADC_TS_BIAS_60UA (2 << 4)
+#define AXP288_ADC_TS_BIAS_80UA (3 << 4)
#define AXP288_ADC_TS_CURRENT_ON_OFF_MASK GENMASK(1, 0)
#define AXP288_ADC_TS_CURRENT_OFF (0 << 0)
#define AXP288_ADC_TS_CURRENT_ON_WHEN_CHARGING (1 << 0)
@@ -177,10 +183,36 @@ static int axp288_adc_read_raw(struct iio_dev *indio_dev,
return ret;
}
+/*
+ * We rely on the machine's firmware to correctly setup the TS pin bias current
+ * at boot. This lists systems with broken fw where we need to set it ourselves.
+ */
+static const struct dmi_system_id axp288_adc_ts_bias_override[] = {
+ {
+ /* Lenovo Ideapad 100S (11 inch) */
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
+ DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo ideapad 100S-11IBY"),
+ },
+ .driver_data = (void *)(uintptr_t)AXP288_ADC_TS_BIAS_80UA,
+ },
+ {}
+};
+
static int axp288_adc_initialize(struct axp288_adc_info *info)
{
+ const struct dmi_system_id *bias_override;
int ret, adc_enable_val;
+ bias_override = dmi_first_match(axp288_adc_ts_bias_override);
+ if (bias_override) {
+ ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL,
+ AXP288_ADC_TS_BIAS_MASK,
+ (uintptr_t)bias_override->driver_data);
+ if (ret)
+ return ret;
+ }
+
/*
* Determine if the TS pin is enabled and set the TS current-source
* accordingly.