Messages in this thread | | | Date | Tue, 10 Mar 2020 12:10:50 +0200 | From | Andy Shevchenko <> | Subject | Re: [PATCH v2 2/2] power: supply: add CellWise cw2015 fuel gauge driver |
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On Mon, Mar 09, 2020 at 05:03:46PM +0100, Tobias Schramm wrote: > This patch adds a driver for the CellWise cw2015 fuel gauge. > > The CellWise cw2015 is a shuntless, single-cell Li-Ion fuel gauge used > in the pine64 Pinebook Pro laptop and some Raspberry Pi UPS HATs.
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> F: arch/powerpc/oprofile/*cell* > F: arch/powerpc/platforms/cell/ > > +CELLWISE CW2015 BATTERY DRIVER > +M: Tobias Schrammm <t.schramm@manjaro.org> > +S: Maintained > +F: drivers/power/supply/cw2015_battery.c > +F: Documentation/devicetree/bindings/power/supply/cw2015_battery.yaml > + > CEPH COMMON CODE (LIBCEPH) > M: Ilya Dryomov <idryomov@gmail.com> > M: Jeff Layton <jlayton@kernel.org>
Run parse-mainteiners.pl and fix ordering issue in above.
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> + * Authors: xuhuicong <xhc@rock-chips.com> > + * Authors: Tobias Schramm <tobias@t-sys.eu>
> + *
Redundant line.
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> +#include <linux/delay.h> > +#include <linux/init.h> > +#include <linux/i2c.h> > +#include <linux/kernel.h> > +#include <linux/module.h>
> +#include <linux/of_gpio.h>
I think you need gpio/consumer.h.
> +#include <linux/platform_device.h> > +#include <linux/power_supply.h> > +#include <linux/slab.h> > +#include <linux/timekeeping.h> > +#include <linux/workqueue.h> > +#include <linux/regmap.h>
Perhaps keep above sorted?
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> +#define CW2015_READ_TRIES 30 > +#define CW2015_RESET_TRIES 5 > + > +#define CW2015_REG_VERSION 0x0 > +#define CW2015_REG_VCELL 0x2 > +#define CW2015_REG_SOC 0x4 > +#define CW2015_REG_RRT_ALERT 0x6 > +#define CW2015_REG_CONFIG 0x8 > +#define CW2015_REG_MODE 0xA > +#define CW2015_REG_BATINFO 0x10
Use same width for all register offsets: 0x08 etc.
> +#define CW2015_MODE_SLEEP_MASK (0x3<<6) > +#define CW2015_MODE_SLEEP (0x3<<6) > +#define CW2015_MODE_NORMAL (0x0<<6) > +#define CW2015_MODE_QUICK_START (0x3<<4) > +#define CW2015_MODE_RESTART (0xf<<0) > + > +#define CW2015_CONFIG_UPDATE_FLG (0x01<<1) > +#define CW2015_ATHD(x) ((x)<<3) > +#define CW2015_MASK_ATHD (0x1f<<3) > +#define CW2015_MASK_SOC (0x1fff)
GENMASK() and somebody missed a lot of white spaces above.
> +#define CW2015_BATTERY_UP_MAX_CHANGE (420 * 1000) > +#define CW2015_BATTERY_DOWN_MAX_CHANGE (120 * 1000) > +#define CW2015_BATTERY_DOWN_CHANGE 60 > +#define CW2015_BATTERY_DOWN_MIN_CHANGE_RUN 30 > +#define CW2015_BATTERY_DOWN_MIN_CHANGE_SLEEP 1800 > +#define CW2015_BATTERY_JUMP_TO_ZERO (30 * 1000) > +#define CW2015_BATTERY_CAPACITY_ERROR (40 * 1000) > +#define CW2015_BATTERY_CHARGING_ZERO (1800 * 1000)
What these multiplications about? We have time units in time.h (or time64.h). Moreover is a good tone to use units in the name of definitions. And try to shorten them, they are already quite long.
> +#define CW2015_DEFAULT_MONITOR_MS 8000
8 seconds? Any comments about this?
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> +struct cw_battery { > + struct i2c_client *client;
Do you need this? Perhaps you can keep struct device from which you can easily retrive the client.
> +};
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> +#define PREFIX "cellwise,"
We have pr_fmt() / dev_fmt() for this.
> +#define cw_dbg(cw_bat, ...) dev_dbg(&(cw_bat)->client->dev, __VA_ARGS__) > +#define cw_info(cw_bat, ...) dev_info(&(cw_bat)->client->dev, __VA_ARGS__) > +#define cw_warn(cw_bat, ...) dev_warn(&(cw_bat)->client->dev, __VA_ARGS__) > +#define cw_err(cw_bat, ...) dev_err(&(cw_bat)->client->dev, __VA_ARGS__)
No, please don't. It doesn't bring any value and makes this small driver harder to read. If you need shorten lines, simple use temporary variable.
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> +static int cw_read(struct cw_battery *cw_bat, u8 reg, u8 *val) > +{ > + u32 tmp; > + int ret; > + > + ret = regmap_read(cw_bat->regmap, reg, &tmp); > + *val = tmp; > + return ret; > +} > + > +static int cw_write(struct cw_battery *cw_bat, u8 reg, const u8 val) > +{ > + return regmap_write(cw_bat->regmap, reg, val); > +}
This two has no value. Why?
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> +static int cw_read_word(struct cw_battery *cw_bat, u8 reg, u16 *val) > +{ > + u8 reg_val[2]; > + int ret; > + > + ret = regmap_raw_read(cw_bat->regmap, reg, reg_val, 2); > + *val = (reg_val[0] << 8) + reg_val[1]; > + return ret; > +}
NIH BE type of readings? Can REGMAP_ENDIAN_BIG help?
> +static int cw_read_bulk(struct cw_battery *cw_bat, u8 reg, u8 *buf, size_t len) > +{ > + return regmap_raw_read(cw_bat->regmap, reg, buf, len); > +}
No value.
> +static int cw_write_bulk(struct cw_battery *cw_bat, u8 reg, u8 const *buf, > + size_t len) > +{ > + return regmap_raw_write(cw_bat->regmap, reg, buf, len); > +}
Ditto.
> +int cw_update_config_info(struct cw_battery *cw_bat) > +{ > + int ret; > + u8 reg_val; > + u8 reset_val; > + > + if (!cw_bat->bat_config_info) { > + cw_err(cw_bat, > + "No battery config info provided, can't update flash contents"); > + return -EINVAL; > + } > + > + /* make sure gauge is not in sleep mode */ > + ret = cw_read(cw_bat, CW2015_REG_MODE, ®_val); > + if (ret < 0) > + return ret; > + > + reset_val = reg_val; > + if ((reg_val & CW2015_MODE_SLEEP_MASK) == CW2015_MODE_SLEEP) { > + cw_err(cw_bat, > + "Device is in sleep mode, can't update battery info"); > + return -EINVAL; > + } > + > + /* write new battery info */ > + ret = cw_write_bulk(cw_bat, CW2015_REG_BATINFO, > + cw_bat->bat_config_info, > + CW2015_SIZE_BATINFO);
> +
Redundant line.
> + if (ret < 0) > + return ret;
All above comparison (and a lot below) are against negative return code, have you checked if positive is ever possible (AFAIR no, they are not possible).
> + reg_val |= CW2015_CONFIG_UPDATE_FLG; /* set UPDATE_FLAG */ > + reg_val &= ~CW2015_MASK_ATHD; /* clear alert level */ > + reg_val |= CW2015_ATHD(cw_bat->alert_level); /* set alert level */
All comments can be replaced with one on top of three
/* Update alert level */
> + ret = cw_write(cw_bat, CW2015_REG_CONFIG, reg_val); > + if (ret < 0) > + return ret; > +
> + /* reset */
Useless.
> + reset_val &= ~(CW2015_MODE_RESTART);
Too many parentheses.
Note all my comments should be applied to all similar places in the code, even if I didn't comment them explicitly.
> + reg_val = reset_val | CW2015_MODE_RESTART; > + ret = cw_write(cw_bat, CW2015_REG_MODE, reg_val); > + if (ret < 0) > + return ret; > + > + msleep(20); > + ret = cw_write(cw_bat, CW2015_REG_MODE, reset_val); > + if (ret < 0) > + return ret; > + > + cw_dbg(cw_bat, "Battery config updated"); > + > + return 0; > +}
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I didn't review some parts because of style issues. Please, fix all of them and send v2.
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> + msleep(20);
This big delay has to be explained.
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> + } else if (charging_5_loop != 0) {
Useless conditional.
> + charging_5_loop = 0; > + }
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> + voltage = avg * 312 / 1024;
All calculations like that better to be explained (like: "Data sheet provides a formula to normalize raw value ... bla bla bla").
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> + else if (cw_bat->capacity != cw_capacity) { > + cw_bat->capacity = cw_capacity;
> + else if (cw_bat->voltage != ret) > + cw_bat->voltage = ret;
Too many useless conditionals.
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> + // calculate remaining capacity
> + // estimate current based on time to empty (in minutes)
You need to choose one comment style over the code.
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> +#ifdef CONFIG_OF
You didn't have of.h in the inclusion block, why do you have this?
Hint: you can easily drop this dependency by using fwnode / device property API.
> +static int cw2015_parse_dt(struct cw_battery *cw_bat) > +{ > + struct device *dev = &cw_bat->client->dev; > + struct device_node *node = dev->of_node; > + struct property *prop; > + int length; > + u32 value; > + int ret; > + > + if (!node) > + return -ENODEV; > +
> + prop = of_find_property(node, PREFIX"bat-config-info", &length);
No, no, please always spell explicitly name of nodes / properties / etc.
> + if (prop) { > + if (length != CW2015_SIZE_BATINFO) { > + cw_err(cw_bat, "bat-config-info must be %d bytes", > + CW2015_SIZE_BATINFO); > + return -EINVAL; > + } > + > + cw_bat->bat_config_info = > + devm_kzalloc(dev, CW2015_SIZE_BATINFO, GFP_KERNEL); > + if (!cw_bat->bat_config_info) { > + cw_err(cw_bat, > + "Failed to allocate memory for battery config info"); > + return -ENOMEM; > + } > + > + ret = of_property_read_u8_array(node, PREFIX"bat-config-info", > + cw_bat->bat_config_info, > + CW2015_SIZE_BATINFO); > + if (ret < 0) > + return ret; > + } else > + cw_warn(cw_bat, > + "No bat-config-info found, rolling with current flash contents"); > + > + cw_bat->monitor_sec = CW2015_DEFAULT_MONITOR_MS; > + > + ret = of_property_read_u32(node, PREFIX"monitor-interval-ms", &value); > + if (ret >= 0) { > + cw_dbg(cw_bat, "Overriding default monitor-interval with %u ms", > + value); > + cw_bat->monitor_sec = value; > + } > + > + return 0; > +} > +#else > +static int cw2015_parse_dt(struct cw_battery *cw_bat) > +{ > + return -ENODEV; > +} > +#endif
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> +static const struct regmap_range regmap_ranges_wr_yes[] = { > + regmap_reg_range(CW2015_REG_RRT_ALERT, CW2015_REG_CONFIG), > + regmap_reg_range(CW2015_REG_MODE, CW2015_REG_MODE),
> + regmap_reg_range(CW2015_REG_BATINFO, CW2015_REG_BATINFO + > + CW2015_SIZE_BATINFO - 1),
Much better to split differently, i.e.
regmap_reg_range(CW2015_REG_BATINFO, CW2015_REG_BATINFO + CW2015_SIZE_BATINFO - 1),
> +};
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> + cw_dbg(cw_bat, "cw2015/cw2013 driver probe success");
Noise.
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> +#ifdef CONFIG_PM
Can be replaced by __maybe_unused attribute to the below functions.
> +static int cw_bat_suspend(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct cw_battery *cw_bat = i2c_get_clientdata(client); > + > + ktime_get_boottime_ts64(&cw_bat->suspend_time_before); > + cancel_delayed_work_sync(&cw_bat->battery_delay_work); > + return 0; > +} > + > +static int cw_bat_resume(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct cw_battery *cw_bat = i2c_get_clientdata(client); > + > + cw_bat->suspend_resume_mark = 1; > + ktime_get_boottime_ts64(&cw_bat->after); > + cw_bat->after = timespec64_sub(cw_bat->after, > + cw_bat->suspend_time_before); > + queue_delayed_work(cw_bat->battery_workqueue, > + &cw_bat->battery_delay_work, msecs_to_jiffies(2)); > + return 0; > +} > +
> +static const struct dev_pm_ops cw_bat_pm_ops = { > + .suspend = cw_bat_suspend, > + .resume = cw_bat_resume, > +};
Use proper helper macro from pm.h instead of above.
> +#endif
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> + cw_dbg(cw_bat, "Removing device");
Noise.
> + cancel_delayed_work(&cw_bat->battery_delay_work);
Are you sure you have no scheduled work after that?
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> +static const struct of_device_id cw2015_of_match[] = { > + { .compatible = PREFIX"cw2015" },
> + { },
No need to have comma for terminator line.
> +};
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> +#ifdef CONFIG_PM > + .pm = &cw_bat_pm_ops, > +#endif
Drop this ifdefery and use proper helper macro above.
-- With Best Regards, Andy Shevchenko
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