Hi Thomas, Am Thu, Jan 02, 2025 at 12:15:03PM +0100 schrieb Thomas Antoine via B4 Relay: > From: Thomas Antoine <t.antoine@xxxxxxxxxxxx> > > The interface of the Maxim max77759 fuel gauge has a lot of common with the > Maxim max1720x. The major difference is the lack of non-volatile memory > slave address. No slave is available at address 0xb of the i2c bus, which > is coherent with the following driver from google: line 5836 disables > non-volatile memory for m5 gauge. > > Link: https://android.googlesource.com/kernel/google-modules/bms/+/1a68c36bef474573cc8629cc1d121eb6a81ab68c/max1720x_battery.c > > Other differences include the lack of V_BATT register to read the battery > level and a difference in the way to identify the chip (the same register > is used but not the same mask). > > Add support for the max77759 by allowing to use the non-volatile > memory or not based on the chip. Also add the V_CELL regsister as a > fallback to read voltage value in the case where read of V_BATT fails. > > The cast is necessary to avoid an overflow when the value of the register > is above 54975 (equivalent to a voltage around 4.29 V). > > The regmap of the max77759 will lead the read to fail for V_BATT and to > correctly use V_CELL instead. This regmap was proposed by André Draszik in > > Link: https://lore.kernel.org/all/d1bade77b5281c1de6b2ddcb4dbbd033e455a116.camel@xxxxxxxxxx/ > > Signed-off-by: Thomas Antoine <t.antoine@xxxxxxxxxxxx> > --- > drivers/power/supply/max1720x_battery.c | 189 +++++++++++++++++++++++++++----- > 1 file changed, 164 insertions(+), 25 deletions(-) > > diff --git a/drivers/power/supply/max1720x_battery.c b/drivers/power/supply/max1720x_battery.c > index 33105419e2427bb37963bda9948b647c239f8faa..a41976679eded44fbd13120ad756a626d2867919 100644 > --- a/drivers/power/supply/max1720x_battery.c > +++ b/drivers/power/supply/max1720x_battery.c > @@ -27,6 +27,7 @@ > #define MAX172XX_REPCAP 0x05 /* Average capacity */ > #define MAX172XX_REPSOC 0x06 /* Percentage of charge */ > #define MAX172XX_TEMP 0x08 /* Temperature */ > +#define MAX172XX_VCELL 0x09 /* Lowest cell voltage */ > #define MAX172XX_CURRENT 0x0A /* Actual current */ > #define MAX172XX_AVG_CURRENT 0x0B /* Average current */ > #define MAX172XX_TTE 0x11 /* Time to empty */ > @@ -39,6 +40,8 @@ > #define MAX172XX_DEV_NAME_TYPE_MASK GENMASK(3, 0) > #define MAX172XX_DEV_NAME_TYPE_MAX17201 BIT(0) > #define MAX172XX_DEV_NAME_TYPE_MAX17205 (BIT(0) | BIT(2)) > +#define MAX77759_DEV_NAME_TYPE_MASK GENMASK(15, 9) > +#define MAX77759_DEV_NAME_TYPE_MAX77759 0x31 > #define MAX172XX_QR_TABLE10 0x22 > #define MAX172XX_BATT 0xDA /* Battery voltage */ > #define MAX172XX_ATAVCAP 0xDF > @@ -46,12 +49,20 @@ > static const char *const max1720x_manufacturer = "Maxim Integrated"; > static const char *const max17201_model = "MAX17201"; > static const char *const max17205_model = "MAX17205"; > +static const char *const max77759_model = "MAX77759"; > + > +enum chip_id { > + MAX1720X_ID, > + MAX77759_ID, > +}; > > struct max1720x_device_info { > struct regmap *regmap; > struct regmap *regmap_nv; > struct i2c_client *ancillary; > int rsense; > + int has_nvmem; Switch to bool and why is needed twice ? Here and in chip_data. Better keep it in chip_data. > + enum chip_id id; > }; > > /* > @@ -254,6 +265,67 @@ static const enum power_supply_property max1720x_battery_props[] = { > POWER_SUPPLY_PROP_MANUFACTURER, > }; > > +/* > + * Registers 0x80 up to 0xaf which contain the model for the fuel gauge > + * algorithm (stored in nvmem for the max1720x) are locked. They can > + * be unlocked by writing 0x59 to 0x62 and 0xc4 to 0x63. They should be > + * enabled in the regmap if the driver is extended to manage the model. > + */ > +static const struct regmap_range max77759_registers[] = { > + regmap_reg_range(0x00, 0x4f), > + regmap_reg_range(0xb0, 0xbf), > + regmap_reg_range(0xd0, 0xd0), > + regmap_reg_range(0xdc, 0xdf), > + regmap_reg_range(0xfb, 0xfb), > + regmap_reg_range(0xff, 0xff), > +}; > + > +static const struct regmap_range max77759_ro_registers[] = { > + regmap_reg_range(0x3d, 0x3d), > + regmap_reg_range(0xfb, 0xfb), > + regmap_reg_range(0xff, 0xff), > +}; > + > +static const struct regmap_access_table max77759_write_table = { > + .yes_ranges = max77759_registers, > + .n_yes_ranges = ARRAY_SIZE(max77759_registers), > + .no_ranges = max77759_ro_registers, > + .n_no_ranges = ARRAY_SIZE(max77759_ro_registers), > +}; > + > +static const struct regmap_access_table max77759_rd_table = { > + .yes_ranges = max77759_registers, > + .n_yes_ranges = ARRAY_SIZE(max77759_registers), > +}; > + > +static const struct regmap_config max77759_regmap_cfg = { > + .reg_bits = 8, > + .val_bits = 16, > + .max_register = 0xff, > + .wr_table = &max77759_write_table, > + .rd_table = &max77759_rd_table, > + .val_format_endian = REGMAP_ENDIAN_LITTLE, > + .cache_type = REGCACHE_NONE, > +}; > + > +struct chip_data { > + u8 has_nvmem; > + const struct regmap_config *regmap_cfg; > + enum chip_id id; > +}; > + > +static const struct chip_data max1720x_data = { > + .has_nvmem = 1, > + .regmap_cfg = &max1720x_regmap_cfg, > + .id = MAX1720X_ID, > +}; > + > +static const struct chip_data max77759_data = { > + .has_nvmem = 0, > + .regmap_cfg = &max77759_regmap_cfg, > + .id = MAX77759_ID, > +}; > + > /* Convert regs value to power_supply units */ > > static int max172xx_time_to_ps(unsigned int reg) > @@ -271,6 +343,14 @@ static int max172xx_voltage_to_ps(unsigned int reg) > return reg * 1250; /* in uV */ > } > > +// Use 64 bits because computation on 32 bits leads to an overflow > +static int max172xx_cell_voltage_to_ps(unsigned int reg) > +{ > + u64 val = reg; > + > + return val * 78125 / 1000; /* in uV */ You could avoid the overflow with: return val * 625 / 8; /* in uV */ > +} > + > static int max172xx_capacity_to_ps(unsigned int reg) > { > return reg * 500; /* in uAh */ > @@ -303,6 +383,33 @@ static int max172xx_current_to_voltage(unsigned int reg) > return val * 156252; > } > > +static int max1720x_devname_to_model(unsigned int reg_val, > + union power_supply_propval *val, > + struct max1720x_device_info *info) nit: Align with open parenthesis > +{ > + switch (info->id) { > + case MAX1720X_ID: > + reg_val = FIELD_GET(MAX172XX_DEV_NAME_TYPE_MASK, reg_val); > + if (reg_val == MAX172XX_DEV_NAME_TYPE_MAX17201) > + val->strval = max17201_model; > + else if (reg_val == MAX172XX_DEV_NAME_TYPE_MAX17205) > + val->strval = max17205_model; > + else > + return -ENODEV; > + break; > + case MAX77759_ID: > + reg_val = FIELD_GET(MAX77759_DEV_NAME_TYPE_MASK, reg_val); > + if (reg_val == MAX77759_DEV_NAME_TYPE_MAX77759) > + val->strval = max77759_model; > + else > + return -ENODEV; > + break; > + default: > + return -ENODEV; > + } > + return 0; > +} > + > static int max1720x_battery_get_property(struct power_supply *psy, > enum power_supply_property psp, > union power_supply_propval *val) > @@ -332,7 +439,12 @@ static int max1720x_battery_get_property(struct power_supply *psy, > break; > case POWER_SUPPLY_PROP_VOLTAGE_NOW: > ret = regmap_read(info->regmap, MAX172XX_BATT, ®_val); > - val->intval = max172xx_voltage_to_ps(reg_val); > + if (!ret) > + val->intval = max172xx_voltage_to_ps(reg_val); > + else { > + ret = regmap_read(info->regmap, MAX172XX_VCELL, ®_val); > + val->intval = max172xx_cell_voltage_to_ps(reg_val); > + } Would be better to read the right register, since we know which device we are. You could differentiate like in max1720x_devname_to_model. > break; > case POWER_SUPPLY_PROP_CHARGE_FULL_DESIGN: > ret = regmap_read(info->regmap, MAX172XX_DESIGN_CAP, ®_val); > @@ -364,13 +476,8 @@ static int max1720x_battery_get_property(struct power_supply *psy, > break; > case POWER_SUPPLY_PROP_MODEL_NAME: > ret = regmap_read(info->regmap, MAX172XX_DEV_NAME, ®_val); > - reg_val = FIELD_GET(MAX172XX_DEV_NAME_TYPE_MASK, reg_val); > - if (reg_val == MAX172XX_DEV_NAME_TYPE_MAX17201) > - val->strval = max17201_model; > - else if (reg_val == MAX172XX_DEV_NAME_TYPE_MAX17205) > - val->strval = max17205_model; > - else > - return -ENODEV; > + if (!ret) > + ret = max1720x_devname_to_model(reg_val, val, info); > break; > case POWER_SUPPLY_PROP_MANUFACTURER: > val->strval = max1720x_manufacturer; > @@ -416,7 +523,6 @@ static int max1720x_probe_nvmem(struct i2c_client *client, > .priv = info, > }; > struct nvmem_device *nvmem; > - unsigned int val; > int ret; > > info->ancillary = i2c_new_ancillary_device(client, "nvmem", 0xb); > @@ -438,18 +544,6 @@ static int max1720x_probe_nvmem(struct i2c_client *client, > return PTR_ERR(info->regmap_nv); > } > > - ret = regmap_read(info->regmap_nv, MAX1720X_NRSENSE, &val); > - if (ret < 0) { > - dev_err(dev, "Failed to read sense resistor value\n"); > - return ret; > - } > - > - info->rsense = val; > - if (!info->rsense) { > - dev_warn(dev, "RSense not calibrated, set 10 mOhms!\n"); > - info->rsense = 1000; /* in regs in 10^-5 */ > - } > - > nvmem = devm_nvmem_register(dev, &nvmem_config); > if (IS_ERR(nvmem)) { > dev_err(dev, "Could not register nvmem!"); > @@ -459,6 +553,36 @@ static int max1720x_probe_nvmem(struct i2c_client *client, > return 0; > } > > +static int max1720x_get_rsense(struct device *dev, > + struct max1720x_device_info *info) nit: Align with open parenthesis. > +{ > + unsigned int val; > + int ret; > + > + if (info->has_nvmem) { > + ret = regmap_read(info->regmap_nv, MAX1720X_NRSENSE, &val); > + if (ret < 0) { > + dev_err(dev, "Failed to read RSense from nvmem\n"); > + return ret; > + } > + > + info->rsense = val; > + if (!info->rsense) { > + dev_warn(dev, "RSense not calibrated, set 10 mOhms!\n"); > + info->rsense = 1000; /* in regs in 10^-5 */ > + } > + } else { > + ret = of_property_read_u32(dev->of_node, > + "shunt-resistor-micro-ohms", &val); nit: Align with open parenthesis. > + if (ret) { > + dev_err(dev, "Failed to read RSense from devicetree\n"); > + return ret; > + } > + info->rsense = val/10; > + } > + return 0; > +} > [...] Best regards, Dimitri Fedrau
