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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/power/supply/bq27xxx_battery_hdq.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/power/supply/bq27xxx_battery_hdq.c')
-rw-r--r-- | drivers/power/supply/bq27xxx_battery_hdq.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/drivers/power/supply/bq27xxx_battery_hdq.c b/drivers/power/supply/bq27xxx_battery_hdq.c new file mode 100644 index 000000000..922759ab2 --- /dev/null +++ b/drivers/power/supply/bq27xxx_battery_hdq.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * BQ27xxx battery monitor HDQ/1-wire driver + * + * Copyright (C) 2007-2017 Texas Instruments Incorporated - https://www.ti.com/ + * + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/types.h> +#include <linux/platform_device.h> +#include <linux/mutex.h> +#include <linux/power/bq27xxx_battery.h> + +#include <linux/w1.h> + +#define W1_FAMILY_BQ27000 0x01 + +#define HDQ_CMD_READ (0 << 7) +#define HDQ_CMD_WRITE (1 << 7) + +static int F_ID; +module_param(F_ID, int, S_IRUSR); +MODULE_PARM_DESC(F_ID, "1-wire slave FID for BQ27xxx device"); + +static int w1_bq27000_read(struct w1_slave *sl, unsigned int reg) +{ + u8 val; + + mutex_lock(&sl->master->bus_mutex); + w1_write_8(sl->master, HDQ_CMD_READ | reg); + val = w1_read_8(sl->master); + mutex_unlock(&sl->master->bus_mutex); + + return val; +} + +static int bq27xxx_battery_hdq_read(struct bq27xxx_device_info *di, u8 reg, + bool single) +{ + struct w1_slave *sl = dev_to_w1_slave(di->dev); + unsigned int timeout = 3; + int upper, lower; + int temp; + + if (!single) { + /* + * Make sure the value has not changed in between reading the + * lower and the upper part + */ + upper = w1_bq27000_read(sl, reg + 1); + do { + temp = upper; + if (upper < 0) + return upper; + + lower = w1_bq27000_read(sl, reg); + if (lower < 0) + return lower; + + upper = w1_bq27000_read(sl, reg + 1); + } while (temp != upper && --timeout); + + if (timeout == 0) + return -EIO; + + return (upper << 8) | lower; + } + + return w1_bq27000_read(sl, reg); +} + +static int bq27xxx_battery_hdq_add_slave(struct w1_slave *sl) +{ + struct bq27xxx_device_info *di; + + di = devm_kzalloc(&sl->dev, sizeof(*di), GFP_KERNEL); + if (!di) + return -ENOMEM; + + dev_set_drvdata(&sl->dev, di); + + di->dev = &sl->dev; + di->chip = BQ27000; + di->name = "bq27000-battery"; + di->bus.read = bq27xxx_battery_hdq_read; + + return bq27xxx_battery_setup(di); +} + +static void bq27xxx_battery_hdq_remove_slave(struct w1_slave *sl) +{ + struct bq27xxx_device_info *di = dev_get_drvdata(&sl->dev); + + bq27xxx_battery_teardown(di); +} + +static const struct w1_family_ops bq27xxx_battery_hdq_fops = { + .add_slave = bq27xxx_battery_hdq_add_slave, + .remove_slave = bq27xxx_battery_hdq_remove_slave, +}; + +static struct w1_family bq27xxx_battery_hdq_family = { + .fid = W1_FAMILY_BQ27000, + .fops = &bq27xxx_battery_hdq_fops, +}; + +static int __init bq27xxx_battery_hdq_init(void) +{ + if (F_ID) + bq27xxx_battery_hdq_family.fid = F_ID; + + return w1_register_family(&bq27xxx_battery_hdq_family); +} +module_init(bq27xxx_battery_hdq_init); + +static void __exit bq27xxx_battery_hdq_exit(void) +{ + w1_unregister_family(&bq27xxx_battery_hdq_family); +} +module_exit(bq27xxx_battery_hdq_exit); + +MODULE_AUTHOR("Texas Instruments Ltd"); +MODULE_DESCRIPTION("BQ27xxx battery monitor HDQ/1-wire driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_BQ27000)); |