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authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-02-18 10:12:12 -0500
committerMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-02-18 10:12:12 -0500
commit5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0 (patch)
treec8e30ba4eaf357699ef97a786bf56661f4591be8 /drivers/iio/adc/axp288_adc.c
parentmedia: vimc: fill in bus_info in media_device_info (diff)
parentLinux 5.0-rc7 (diff)
downloadlinux-dev-5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0.tar.xz
linux-dev-5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0.zip
Merge tag 'v5.0-rc7' into patchwork
Linux 5.0-rc7 * tag 'v5.0-rc7': (1667 commits) Linux 5.0-rc7 Input: elan_i2c - add ACPI ID for touchpad in Lenovo V330-15ISK Input: st-keyscan - fix potential zalloc NULL dereference Input: apanel - switch to using brightness_set_blocking() powerpc/64s: Fix possible corruption on big endian due to pgd/pud_present() efi/arm: Revert "Defer persistent reservations until after paging_init()" arm64, mm, efi: Account for GICv3 LPI tables in static memblock reserve table sunrpc: fix 4 more call sites that were using stack memory with a scatterlist include/linux/module.h: copy __init/__exit attrs to init/cleanup_module Compiler Attributes: add support for __copy (gcc >= 9) lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure auxdisplay: ht16k33: fix potential user-after-free on module unload x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls i2c: bcm2835: Clear current buffer pointers and counts after a transfer i2c: cadence: Fix the hold bit setting drm: Use array_size() when creating lease dm thin: fix bug where bio that overwrites thin block ignores FUA Revert "exec: load_script: don't blindly truncate shebang string" Revert "gfs2: read journal in large chunks to locate the head" net: ethernet: freescale: set FEC ethtool regs version ... Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Diffstat (limited to 'drivers/iio/adc/axp288_adc.c')
-rw-r--r--drivers/iio/adc/axp288_adc.c76
1 files changed, 60 insertions, 16 deletions
diff --git a/drivers/iio/adc/axp288_adc.c b/drivers/iio/adc/axp288_adc.c
index 031d568b4972..4e339cfd0c54 100644
--- a/drivers/iio/adc/axp288_adc.c
+++ b/drivers/iio/adc/axp288_adc.c
@@ -27,9 +27,18 @@
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>
-#define AXP288_ADC_EN_MASK 0xF1
-#define AXP288_ADC_TS_PIN_GPADC 0xF2
-#define AXP288_ADC_TS_PIN_ON 0xF3
+/*
+ * This mask enables all ADCs except for the battery temp-sensor (TS), that is
+ * left as-is to avoid breaking charging on devices without a temp-sensor.
+ */
+#define AXP288_ADC_EN_MASK 0xF0
+#define AXP288_ADC_TS_ENABLE 0x01
+
+#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)
+#define AXP288_ADC_TS_CURRENT_ON_ONDEMAND (2 << 0)
+#define AXP288_ADC_TS_CURRENT_ON (3 << 0)
enum axp288_adc_id {
AXP288_ADC_TS,
@@ -44,6 +53,7 @@ enum axp288_adc_id {
struct axp288_adc_info {
int irq;
struct regmap *regmap;
+ bool ts_enabled;
};
static const struct iio_chan_spec axp288_adc_channels[] = {
@@ -115,21 +125,33 @@ static int axp288_adc_read_channel(int *val, unsigned long address,
return IIO_VAL_INT;
}
-static int axp288_adc_set_ts(struct regmap *regmap, unsigned int mode,
- unsigned long address)
+/*
+ * The current-source used for the battery temp-sensor (TS) is shared
+ * with the GPADC. For proper fuel-gauge and charger operation the TS
+ * current-source needs to be permanently on. But to read the GPADC we
+ * need to temporary switch the TS current-source to ondemand, so that
+ * the GPADC can use it, otherwise we will always read an all 0 value.
+ */
+static int axp288_adc_set_ts(struct axp288_adc_info *info,
+ unsigned int mode, unsigned long address)
{
int ret;
- /* channels other than GPADC do not need to switch TS pin */
+ /* No need to switch the current-source if the TS pin is disabled */
+ if (!info->ts_enabled)
+ return 0;
+
+ /* Channels other than GPADC do not need the current source */
if (address != AXP288_GP_ADC_H)
return 0;
- ret = regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, mode);
+ ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL,
+ AXP288_ADC_TS_CURRENT_ON_OFF_MASK, mode);
if (ret)
return ret;
/* When switching to the GPADC pin give things some time to settle */
- if (mode == AXP288_ADC_TS_PIN_GPADC)
+ if (mode == AXP288_ADC_TS_CURRENT_ON_ONDEMAND)
usleep_range(6000, 10000);
return 0;
@@ -145,14 +167,14 @@ static int axp288_adc_read_raw(struct iio_dev *indio_dev,
mutex_lock(&indio_dev->mlock);
switch (mask) {
case IIO_CHAN_INFO_RAW:
- if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_GPADC,
+ if (axp288_adc_set_ts(info, AXP288_ADC_TS_CURRENT_ON_ONDEMAND,
chan->address)) {
dev_err(&indio_dev->dev, "GPADC mode\n");
ret = -EINVAL;
break;
}
ret = axp288_adc_read_channel(val, chan->address, info->regmap);
- if (axp288_adc_set_ts(info->regmap, AXP288_ADC_TS_PIN_ON,
+ if (axp288_adc_set_ts(info, AXP288_ADC_TS_CURRENT_ON,
chan->address))
dev_err(&indio_dev->dev, "TS pin restore\n");
break;
@@ -164,13 +186,35 @@ static int axp288_adc_read_raw(struct iio_dev *indio_dev,
return ret;
}
-static int axp288_adc_set_state(struct regmap *regmap)
+static int axp288_adc_initialize(struct axp288_adc_info *info)
{
- /* ADC should be always enabled for internal FG to function */
- if (regmap_write(regmap, AXP288_ADC_TS_PIN_CTRL, AXP288_ADC_TS_PIN_ON))
- return -EIO;
+ int ret, adc_enable_val;
+
+ /*
+ * Determine if the TS pin is enabled and set the TS current-source
+ * accordingly.
+ */
+ ret = regmap_read(info->regmap, AXP20X_ADC_EN1, &adc_enable_val);
+ if (ret)
+ return ret;
+
+ if (adc_enable_val & AXP288_ADC_TS_ENABLE) {
+ info->ts_enabled = true;
+ ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL,
+ AXP288_ADC_TS_CURRENT_ON_OFF_MASK,
+ AXP288_ADC_TS_CURRENT_ON);
+ } else {
+ info->ts_enabled = false;
+ ret = regmap_update_bits(info->regmap, AXP288_ADC_TS_PIN_CTRL,
+ AXP288_ADC_TS_CURRENT_ON_OFF_MASK,
+ AXP288_ADC_TS_CURRENT_OFF);
+ }
+ if (ret)
+ return ret;
- return regmap_write(regmap, AXP20X_ADC_EN1, AXP288_ADC_EN_MASK);
+ /* Turn on the ADC for all channels except TS, leave TS as is */
+ return regmap_update_bits(info->regmap, AXP20X_ADC_EN1,
+ AXP288_ADC_EN_MASK, AXP288_ADC_EN_MASK);
}
static const struct iio_info axp288_adc_iio_info = {
@@ -200,7 +244,7 @@ static int axp288_adc_probe(struct platform_device *pdev)
* Set ADC to enabled state at all time, including system suspend.
* otherwise internal fuel gauge functionality may be affected.
*/
- ret = axp288_adc_set_state(axp20x->regmap);
+ ret = axp288_adc_initialize(info);
if (ret) {
dev_err(&pdev->dev, "unable to enable ADC device\n");
return ret;