diff options
Diffstat (limited to 'drivers/w1/slaves/w1_therm.c')
| -rw-r--r-- | drivers/w1/slaves/w1_therm.c | 164 |
1 files changed, 135 insertions, 29 deletions
diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c index cb3fc3c6b0d1..259525c3382a 100644 --- a/drivers/w1/slaves/w1_therm.c +++ b/drivers/w1/slaves/w1_therm.c @@ -29,6 +29,7 @@ #include <linux/types.h> #include <linux/slab.h> #include <linux/delay.h> +#include <linux/hwmon.h> #include <linux/w1.h> @@ -59,6 +60,12 @@ struct w1_therm_family_data { atomic_t refcnt; }; +struct therm_info { + u8 rom[9]; + u8 crc; + u8 verdict; +}; + /* return the address of the refcnt in the family data */ #define THERM_REFCNT(family_data) \ (&((struct w1_therm_family_data *)family_data)->refcnt) @@ -107,19 +114,72 @@ static struct attribute *w1_ds28ea00_attrs[] = { &dev_attr_w1_seq.attr, NULL, }; + ATTRIBUTE_GROUPS(w1_therm); ATTRIBUTE_GROUPS(w1_ds28ea00); +#if IS_REACHABLE(CONFIG_HWMON) +static int w1_read_temp(struct device *dev, u32 attr, int channel, + long *val); + +static umode_t w1_is_visible(const void *_data, enum hwmon_sensor_types type, + u32 attr, int channel) +{ + return attr == hwmon_temp_input ? 0444 : 0; +} + +static int w1_read(struct device *dev, enum hwmon_sensor_types type, + u32 attr, int channel, long *val) +{ + switch (type) { + case hwmon_temp: + return w1_read_temp(dev, attr, channel, val); + default: + return -EOPNOTSUPP; + } +} + +static const u32 w1_temp_config[] = { + HWMON_T_INPUT, + 0 +}; + +static const struct hwmon_channel_info w1_temp = { + .type = hwmon_temp, + .config = w1_temp_config, +}; + +static const struct hwmon_channel_info *w1_info[] = { + &w1_temp, + NULL +}; + +static const struct hwmon_ops w1_hwmon_ops = { + .is_visible = w1_is_visible, + .read = w1_read, +}; + +static const struct hwmon_chip_info w1_chip_info = { + .ops = &w1_hwmon_ops, + .info = w1_info, +}; +#define W1_CHIPINFO (&w1_chip_info) +#else +#define W1_CHIPINFO NULL +#endif + static struct w1_family_ops w1_therm_fops = { .add_slave = w1_therm_add_slave, .remove_slave = w1_therm_remove_slave, .groups = w1_therm_groups, + .chip_info = W1_CHIPINFO, }; static struct w1_family_ops w1_ds28ea00_fops = { .add_slave = w1_therm_add_slave, .remove_slave = w1_therm_remove_slave, .groups = w1_ds28ea00_groups, + .chip_info = W1_CHIPINFO, }; static struct w1_family w1_therm_family_DS18S20 = { @@ -422,33 +482,31 @@ static ssize_t w1_slave_store(struct device *device, return ret ? : size; } -static ssize_t w1_slave_show(struct device *device, - struct device_attribute *attr, char *buf) +static ssize_t read_therm(struct device *device, + struct w1_slave *sl, struct therm_info *info) { - struct w1_slave *sl = dev_to_w1_slave(device); struct w1_master *dev = sl->master; - u8 rom[9], crc, verdict, external_power; - int i, ret, max_trying = 10; - ssize_t c = PAGE_SIZE; + u8 external_power; + int ret, max_trying = 10; u8 *family_data = sl->family_data; ret = mutex_lock_interruptible(&dev->bus_mutex); if (ret != 0) - goto post_unlock; + goto error; - if (!sl->family_data) { + if (!family_data) { ret = -ENODEV; - goto pre_unlock; + goto mt_unlock; } /* prevent the slave from going away in sleep */ atomic_inc(THERM_REFCNT(family_data)); - memset(rom, 0, sizeof(rom)); + memset(info->rom, 0, sizeof(info->rom)); while (max_trying--) { - verdict = 0; - crc = 0; + info->verdict = 0; + info->crc = 0; if (!w1_reset_select_slave(sl)) { int count = 0; @@ -474,47 +532,69 @@ static ssize_t w1_slave_show(struct device *device, sleep_rem = msleep_interruptible(tm); if (sleep_rem != 0) { ret = -EINTR; - goto post_unlock; + goto dec_refcnt; } ret = mutex_lock_interruptible(&dev->bus_mutex); if (ret != 0) - goto post_unlock; + goto dec_refcnt; } else if (!w1_strong_pullup) { sleep_rem = msleep_interruptible(tm); if (sleep_rem != 0) { ret = -EINTR; - goto pre_unlock; + goto dec_refcnt; } } if (!w1_reset_select_slave(sl)) { w1_write_8(dev, W1_READ_SCRATCHPAD); - count = w1_read_block(dev, rom, 9); + count = w1_read_block(dev, info->rom, 9); if (count != 9) { dev_warn(device, "w1_read_block() " "returned %u instead of 9.\n", count); } - crc = w1_calc_crc8(rom, 8); + info->crc = w1_calc_crc8(info->rom, 8); - if (rom[8] == crc) - verdict = 1; + if (info->rom[8] == info->crc) + info->verdict = 1; } } - if (verdict) + if (info->verdict) break; } +dec_refcnt: + atomic_dec(THERM_REFCNT(family_data)); +mt_unlock: + mutex_unlock(&dev->bus_mutex); +error: + return ret; +} + +static ssize_t w1_slave_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct w1_slave *sl = dev_to_w1_slave(device); + struct therm_info info; + u8 *family_data = sl->family_data; + int ret, i; + ssize_t c = PAGE_SIZE; + u8 fid = sl->family->fid; + + ret = read_therm(device, sl, &info); + if (ret) + return ret; + for (i = 0; i < 9; ++i) - c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", rom[i]); + c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ", info.rom[i]); c -= snprintf(buf + PAGE_SIZE - c, c, ": crc=%02x %s\n", - crc, (verdict) ? "YES" : "NO"); - if (verdict) - memcpy(family_data, rom, sizeof(rom)); + info.crc, (info.verdict) ? "YES" : "NO"); + if (info.verdict) + memcpy(family_data, info.rom, sizeof(info.rom)); else dev_warn(device, "Read failed CRC check\n"); @@ -523,16 +603,42 @@ static ssize_t w1_slave_show(struct device *device, ((u8 *)family_data)[i]); c -= snprintf(buf + PAGE_SIZE - c, c, "t=%d\n", - w1_convert_temp(rom, sl->family->fid)); + w1_convert_temp(info.rom, fid)); ret = PAGE_SIZE - c; + return ret; +} -pre_unlock: - mutex_unlock(&dev->bus_mutex); +#if IS_REACHABLE(CONFIG_HWMON) +static int w1_read_temp(struct device *device, u32 attr, int channel, + long *val) +{ + struct w1_slave *sl = dev_get_drvdata(device); + struct therm_info info; + u8 fid = sl->family->fid; + int ret; + + switch (attr) { + case hwmon_temp_input: + ret = read_therm(device, sl, &info); + if (ret) + return ret; + + if (!info.verdict) { + ret = -EIO; + return ret; + } + + *val = w1_convert_temp(info.rom, fid); + ret = 0; + break; + default: + ret = -EOPNOTSUPP; + break; + } -post_unlock: - atomic_dec(THERM_REFCNT(family_data)); return ret; } +#endif #define W1_42_CHAIN 0x99 #define W1_42_CHAIN_OFF 0x3C |