power: supply: bq25890: Support higher charging voltages through Pump Express+ protocol

Add a "linux,pump-express-vbus-max" property which indicates if the Pump
Express+ protocol should be used to increase the charging protocol.

If this new property is set and a DCP charger is detected then request
a higher charging voltage through the Pump Express+ protocol.

So far this new property is only used on x86/ACPI (non devicetree) devs,
IOW it is not used in actual devicetree files. The devicetree-bindings
maintainers have requested properties like these to not be added to the
devicetree-bindings, so the new property is deliberately not added
to the existing devicetree-bindings.

Changes by Hans de Goede:
- Port to my bq25890 patch-series + various cleanups
- Make behavior configurable through a new "linux,pump-express-vbus-max"
  device-property
- Sleep 1 second before re-checking the Vbus voltage after requesting
  it to be raised, to ensure that the ADC has time to sampled the new Vbus
- Add VBUSV bq25890_tables[] entry and use it in bq25890_get_vbus_voltage()
- Tweak commit message

Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Co-developed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

diff --git a/drivers/power/supply/bq25890_charger.c b/drivers/power/supply/bq25890_charger.c
index 3de72f0..179abed 100644 (file)
--- a/drivers/power/supply/bq25890_charger.c
+++ b/drivers/power/supply/bq25890_charger.c
@@ -27,6 +27,10 @@
 #define BQ25895_ID                     7
 #define BQ25896_ID                     0
 
+#define PUMP_EXPRESS_START_DELAY       (5 * HZ)
+#define PUMP_EXPRESS_MAX_TRIES         6
+#define PUMP_EXPRESS_VBUS_MARGIN_uV    1000000
+
 enum bq25890_chip_version {
        BQ25890,
        BQ25892,
@@ -107,6 +111,7 @@ struct bq25890_device {
        struct usb_phy *usb_phy;
        struct notifier_block usb_nb;
        struct work_struct usb_work;
+       struct delayed_work pump_express_work;
        unsigned long usb_event;
 
        struct regmap *rmap;
@@ -114,6 +119,7 @@ struct bq25890_device {
 
        bool skip_reset;
        bool read_back_init_data;
+       u32 pump_express_vbus_max;
        enum bq25890_chip_version chip_version;
        struct bq25890_init_data init_data;
        struct bq25890_state state;
@@ -265,6 +271,7 @@ enum bq25890_table_ids {
        TBL_VREG,
        TBL_BOOSTV,
        TBL_SYSVMIN,
+       TBL_VBUSV,
        TBL_VBATCOMP,
        TBL_RBATCOMP,
 
@@ -325,14 +332,15 @@ static const union {
 } bq25890_tables[] = {
        /* range tables */
        /* TODO: BQ25896 has max ICHG 3008 mA */
-       [TBL_ICHG] =    { .rt = {0,       5056000, 64000} },     /* uA */
-       [TBL_ITERM] =   { .rt = {64000,   1024000, 64000} },     /* uA */
-       [TBL_IINLIM] =  { .rt = {100000,  3250000, 50000} },     /* uA */
-       [TBL_VREG] =    { .rt = {3840000, 4608000, 16000} },     /* uV */
-       [TBL_BOOSTV] =  { .rt = {4550000, 5510000, 64000} },     /* uV */
-       [TBL_SYSVMIN] = { .rt = {3000000, 3700000, 100000} },    /* uV */
-       [TBL_VBATCOMP] ={ .rt = {0,        224000, 32000} },     /* uV */
-       [TBL_RBATCOMP] ={ .rt = {0,        140000, 20000} },     /* uOhm */
+       [TBL_ICHG] =     { .rt = {0,        5056000, 64000} },   /* uA */
+       [TBL_ITERM] =    { .rt = {64000,    1024000, 64000} },   /* uA */
+       [TBL_IINLIM] =   { .rt = {100000,   3250000, 50000} },   /* uA */
+       [TBL_VREG] =     { .rt = {3840000,  4608000, 16000} },   /* uV */
+       [TBL_BOOSTV] =   { .rt = {4550000,  5510000, 64000} },   /* uV */
+       [TBL_SYSVMIN] =  { .rt = {3000000,  3700000, 100000} },  /* uV */
+       [TBL_VBUSV] =    { .rt = {2600000, 15300000, 100000} },  /* uV */
+       [TBL_VBATCOMP] = { .rt = {0,         224000, 32000} },   /* uV */
+       [TBL_RBATCOMP] = { .rt = {0,         140000, 20000} },   /* uOhm */
 
        /* lookup tables */
        [TBL_TREG] =    { .lt = {bq25890_treg_tbl, BQ25890_TREG_TBL_SIZE} },
@@ -435,6 +443,17 @@ static bool bq25890_is_adc_property(enum power_supply_property psp)
 
 static irqreturn_t __bq25890_handle_irq(struct bq25890_device *bq);
 
+static int bq25890_get_vbus_voltage(struct bq25890_device *bq)
+{
+       int ret;
+
+       ret = bq25890_field_read(bq, F_VBUSV);
+       if (ret < 0)
+               return ret;
+
+       return bq25890_find_val(ret, TBL_VBUSV);
+}
+
 static int bq25890_power_supply_get_property(struct power_supply *psy,
                                             enum power_supply_property psp,
                                             union power_supply_propval *val)
@@ -613,6 +632,11 @@ static void bq25890_charger_external_power_changed(struct power_supply *psy)
        switch (val.intval) {
        case POWER_SUPPLY_USB_TYPE_DCP:
                input_current_limit = bq25890_find_idx(2000000, TBL_IINLIM);
+               if (bq->pump_express_vbus_max) {
+                       queue_delayed_work(system_power_efficient_wq,
+                                          &bq->pump_express_work,
+                                          PUMP_EXPRESS_START_DELAY);
+               }
                break;
        case POWER_SUPPLY_USB_TYPE_CDP:
        case POWER_SUPPLY_USB_TYPE_ACA:
@@ -878,6 +902,53 @@ static int bq25890_set_otg_cfg(struct bq25890_device *bq, u8 val)
        return ret;
 }
 
+static void bq25890_pump_express_work(struct work_struct *data)
+{
+       struct bq25890_device *bq =
+               container_of(data, struct bq25890_device, pump_express_work.work);
+       int voltage, i, ret;
+
+       dev_dbg(bq->dev, "Start to request input voltage increasing\n");
+
+       /* Enable current pulse voltage control protocol */
+       ret = bq25890_field_write(bq, F_PUMPX_EN, 1);
+       if (ret < 0)
+               goto error_print;
+
+       for (i = 0; i < PUMP_EXPRESS_MAX_TRIES; i++) {
+               voltage = bq25890_get_vbus_voltage(bq);
+               if (voltage < 0)
+                       goto error_print;
+               dev_dbg(bq->dev, "input voltage = %d uV\n", voltage);
+
+               if ((voltage + PUMP_EXPRESS_VBUS_MARGIN_uV) >
+                                       bq->pump_express_vbus_max)
+                       break;
+
+               ret = bq25890_field_write(bq, F_PUMPX_UP, 1);
+               if (ret < 0)
+                       goto error_print;
+
+               /* Note a single PUMPX up pulse-sequence takes 2.1s */
+               ret = regmap_field_read_poll_timeout(bq->rmap_fields[F_PUMPX_UP],
+                                                    ret, !ret, 100000, 3000000);
+               if (ret < 0)
+                       goto error_print;
+
+               /* Make sure ADC has sampled Vbus before checking again */
+               msleep(1000);
+       }
+
+       bq25890_field_write(bq, F_PUMPX_EN, 0);
+
+       dev_info(bq->dev, "Hi-voltage charging requested, input voltage is %d mV\n",
+                voltage);
+
+       return;
+error_print:
+       dev_err(bq->dev, "Failed to request hi-voltage charging\n");
+}
+
 static void bq25890_usb_work(struct work_struct *data)
 {
        int ret;
@@ -1068,6 +1139,10 @@ static int bq25890_fw_probe(struct bq25890_device *bq)
        int ret;
        struct bq25890_init_data *init = &bq->init_data;
 
+       /* Optional, left at 0 if property is not present */
+       device_property_read_u32(bq->dev, "linux,pump-express-vbus-max",
+                                &bq->pump_express_vbus_max);
+
        bq->skip_reset = device_property_read_bool(bq->dev, "linux,skip-reset");
        bq->read_back_init_data = device_property_read_bool(bq->dev,
                                                "linux,read-back-settings");
@@ -1100,6 +1175,7 @@ static int bq25890_probe(struct i2c_client *client,
        bq->dev = dev;
 
        mutex_init(&bq->lock);
+       INIT_DELAYED_WORK(&bq->pump_express_work, bq25890_pump_express_work);
 
        bq->rmap = devm_regmap_init_i2c(client, &bq25890_regmap_config);
        if (IS_ERR(bq->rmap))