From 376e1a937b3056802f3ad86811ec92ee3f49d560 Mon Sep 17 00:00:00 2001 From: Frank Crawford Date: Sun, 16 Apr 2023 14:25:09 +1000 Subject: [PATCH] hwmon: (it87) Add calls to smbus_enable/smbus_disable as required Disable/re-enable access through SMBus for chip registers when they are are being read or written. For simple cases this is done at the same time as when a mutex is set, however, within loops or during initialisation it is done separately. Signed-off-by: Frank Crawford [groeck: Fixed multi-line alignment] Signed-off-by: Guenter Roeck --- drivers/hwmon/it87.c | 181 ++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 135 insertions(+), 46 deletions(-) diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c index 5083ec0..cb97b3f 100644 --- a/drivers/hwmon/it87.c +++ b/drivers/hwmon/it87.c @@ -746,6 +746,7 @@ static int smbus_enable(struct it87_data *data) /* * Must be called with data->update_lock held, except during initialization. + * Must be called with SMBus accesses disabled. * We ignore the IT87 BUSY flag at this moment - it could lead to deadlocks, * would slow down the IT87 access and should not be necessary. */ @@ -757,6 +758,7 @@ static int it87_read_value(struct it87_data *data, u8 reg) /* * Must be called with data->update_lock held, except during initialization. + * Must be called with SMBus accesses disabled. * We ignore the IT87 BUSY flag at this moment - it could lead to deadlocks, * would slow down the IT87 access and should not be necessary. */ @@ -816,15 +818,39 @@ static void it87_update_pwm_ctrl(struct it87_data *data, int nr) } } +static int it87_lock(struct it87_data *data) +{ + int err; + + mutex_lock(&data->update_lock); + err = smbus_disable(data); + if (err) + mutex_unlock(&data->update_lock); + return err; +} + +static void it87_unlock(struct it87_data *data) +{ + smbus_enable(data); + mutex_unlock(&data->update_lock); +} + static struct it87_data *it87_update_device(struct device *dev) { struct it87_data *data = dev_get_drvdata(dev); + struct it87_data *ret = data; + int err; int i; mutex_lock(&data->update_lock); if (time_after(jiffies, data->last_updated + HZ + HZ / 2) || - !data->valid) { + !data->valid) { + err = smbus_disable(data); + if (err) { + ret = ERR_PTR(err); + goto unlock; + } if (update_vbat) { /* * Cleared after each update, so reenable. Value @@ -927,11 +953,11 @@ static struct it87_data *it87_update_device(struct device *dev) } data->last_updated = jiffies; data->valid = true; + smbus_enable(data); } - +unlock: mutex_unlock(&data->update_lock); - - return data; + return ret; } static ssize_t show_in(struct device *dev, struct device_attribute *attr, @@ -956,17 +982,21 @@ static ssize_t set_in(struct device *dev, struct device_attribute *attr, int index = sattr->index; int nr = sattr->nr; unsigned long val; + int err; if (kstrtoul(buf, 10, &val) < 0) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + data->in[nr][index] = in_to_reg(data, nr, val); it87_write_value(data, index == 1 ? IT87_REG_VIN_MIN(nr) : IT87_REG_VIN_MAX(nr), data->in[nr][index]); - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1048,11 +1078,14 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *attr, struct it87_data *data = dev_get_drvdata(dev); long val; u8 reg, regval; + int err; if (kstrtol(buf, 10, &val) < 0) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; switch (index) { default: @@ -1075,7 +1108,7 @@ static ssize_t set_temp(struct device *dev, struct device_attribute *attr, data->temp[nr][index] = TEMP_TO_REG(val); it87_write_value(data, reg, data->temp[nr][index]); - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1137,10 +1170,15 @@ static ssize_t set_temp_type(struct device *dev, struct device_attribute *attr, struct it87_data *data = dev_get_drvdata(dev); long val; u8 reg, extra; + int err; if (kstrtol(buf, 10, &val) < 0) return -EINVAL; + err = it87_lock(data); + if (err) + return err; + reg = it87_read_value(data, IT87_REG_TEMP_ENABLE); reg &= ~(1 << nr); reg &= ~(8 << nr); @@ -1163,17 +1201,19 @@ static ssize_t set_temp_type(struct device *dev, struct device_attribute *attr, reg |= (nr + 1) << 6; else if (has_temp_old_peci(data, nr) && val == 6) extra |= 0x80; - else if (val != 0) - return -EINVAL; + else if (val != 0) { + count = -EINVAL; + goto unlock; + } - mutex_lock(&data->update_lock); data->sensor = reg; data->extra = extra; it87_write_value(data, IT87_REG_TEMP_ENABLE, data->sensor); if (has_temp_old_peci(data, nr)) it87_write_value(data, IT87_REG_TEMP_EXTRA, data->extra); data->valid = false; /* Force cache refresh */ - mutex_unlock(&data->update_lock); +unlock: + it87_unlock(data); return count; } @@ -1289,12 +1329,15 @@ static ssize_t set_fan(struct device *dev, struct device_attribute *attr, struct it87_data *data = dev_get_drvdata(dev); long val; + int err; u8 reg; if (kstrtol(buf, 10, &val) < 0) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; if (has_16bit_fans(data)) { data->fan[nr][index] = FAN16_TO_REG(val); @@ -1321,7 +1364,7 @@ static ssize_t set_fan(struct device *dev, struct device_attribute *attr, data->fan[nr][index]); } - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1332,13 +1375,16 @@ static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr, struct it87_data *data = dev_get_drvdata(dev); int nr = sensor_attr->index; unsigned long val; - int min; + int min, err; u8 old; if (kstrtoul(buf, 10, &val) < 0) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + old = it87_read_value(data, IT87_REG_FAN_DIV); /* Save fan min limit */ @@ -1366,7 +1412,7 @@ static ssize_t set_fan_div(struct device *dev, struct device_attribute *attr, data->fan[nr][1] = FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr])); it87_write_value(data, IT87_REG_FAN_MIN[nr], data->fan[nr][1]); - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1407,6 +1453,7 @@ static ssize_t set_pwm_enable(struct device *dev, struct device_attribute *attr, struct it87_data *data = dev_get_drvdata(dev); int nr = sensor_attr->index; long val; + int err; if (kstrtol(buf, 10, &val) < 0 || val < 0 || val > 2) return -EINVAL; @@ -1417,7 +1464,9 @@ static ssize_t set_pwm_enable(struct device *dev, struct device_attribute *attr, return -EINVAL; } - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; if (val == 0) { if (nr < 3 && data->type != it8603) { @@ -1468,7 +1517,7 @@ static ssize_t set_pwm_enable(struct device *dev, struct device_attribute *attr, } } - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1479,11 +1528,15 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, struct it87_data *data = dev_get_drvdata(dev); int nr = sensor_attr->index; long val; + int err; if (kstrtol(buf, 10, &val) < 0 || val < 0 || val > 255) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + it87_update_pwm_ctrl(data, nr); if (has_newer_autopwm(data)) { /* @@ -1491,8 +1544,8 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, * is read-only so we can't write the value. */ if (data->pwm_ctrl[nr] & 0x80) { - mutex_unlock(&data->update_lock); - return -EBUSY; + count = -EBUSY; + goto unlock; } data->pwm_duty[nr] = pwm_to_reg(data, val); it87_write_value(data, IT87_REG_PWM_DUTY[nr], @@ -1509,7 +1562,8 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *attr, data->pwm_ctrl[nr]); } } - mutex_unlock(&data->update_lock); +unlock: + it87_unlock(data); return count; } @@ -1520,6 +1574,7 @@ static ssize_t set_pwm_freq(struct device *dev, struct device_attribute *attr, struct it87_data *data = dev_get_drvdata(dev); int nr = sensor_attr->index; unsigned long val; + int err; int i; if (kstrtoul(buf, 10, &val) < 0) @@ -1534,7 +1589,10 @@ static ssize_t set_pwm_freq(struct device *dev, struct device_attribute *attr, break; } - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + if (nr == 0) { data->fan_ctl = it87_read_value(data, IT87_REG_FAN_CTL) & 0x8f; data->fan_ctl |= i << 4; @@ -1544,7 +1602,7 @@ static ssize_t set_pwm_freq(struct device *dev, struct device_attribute *attr, data->extra |= i << 4; it87_write_value(data, IT87_REG_TEMP_EXTRA, data->extra); } - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1577,6 +1635,7 @@ static ssize_t set_pwm_temp_map(struct device *dev, struct it87_data *data = dev_get_drvdata(dev); int nr = sensor_attr->index; long val; + int err; u8 reg; if (kstrtol(buf, 10, &val) < 0) @@ -1599,7 +1658,10 @@ static ssize_t set_pwm_temp_map(struct device *dev, return -EINVAL; } - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + it87_update_pwm_ctrl(data, nr); data->pwm_temp_map[nr] = reg; /* @@ -1611,7 +1673,7 @@ static ssize_t set_pwm_temp_map(struct device *dev, data->pwm_temp_map[nr]; it87_write_value(data, IT87_REG_PWM[nr], data->pwm_ctrl[nr]); } - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1641,18 +1703,22 @@ static ssize_t set_auto_pwm(struct device *dev, struct device_attribute *attr, int point = sensor_attr->index; int regaddr; long val; + int err; if (kstrtol(buf, 10, &val) < 0 || val < 0 || val > 255) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + data->auto_pwm[nr][point] = pwm_to_reg(data, val); if (has_newer_autopwm(data)) regaddr = IT87_REG_AUTO_TEMP(nr, 3); else regaddr = IT87_REG_AUTO_PWM(nr, point); it87_write_value(data, regaddr, data->auto_pwm[nr][point]); - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1677,15 +1743,19 @@ static ssize_t set_auto_pwm_slope(struct device *dev, struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr); int nr = sensor_attr->index; unsigned long val; + int err; if (kstrtoul(buf, 10, &val) < 0 || val > 127) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + data->auto_pwm[nr][1] = (data->auto_pwm[nr][1] & 0x80) | val; it87_write_value(data, IT87_REG_AUTO_TEMP(nr, 4), data->auto_pwm[nr][1]); - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1720,11 +1790,15 @@ static ssize_t set_auto_temp(struct device *dev, struct device_attribute *attr, int point = sensor_attr->index; long val; int reg; + int err; if (kstrtol(buf, 10, &val) < 0 || val < -128000 || val > 127000) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + if (has_newer_autopwm(data) && !point) { reg = data->auto_temp[nr][1] - TEMP_TO_REG(val); reg = clamp_val(reg, 0, 0x1f) | (data->auto_temp[nr][0] & 0xe0); @@ -1737,7 +1811,7 @@ static ssize_t set_auto_temp(struct device *dev, struct device_attribute *attr, point--; it87_write_value(data, IT87_REG_AUTO_TEMP(nr, point), reg); } - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -1946,13 +2020,16 @@ static ssize_t clear_intrusion(struct device *dev, size_t count) { struct it87_data *data = dev_get_drvdata(dev); - int config; + int err, config; long val; if (kstrtol(buf, 10, &val) < 0 || val != 0) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + config = it87_read_value(data, IT87_REG_CONFIG); if (config < 0) { count = config; @@ -1962,8 +2039,7 @@ static ssize_t clear_intrusion(struct device *dev, /* Invalidate cache to force re-read */ data->valid = false; } - mutex_unlock(&data->update_lock); - + it87_unlock(data); return count; } @@ -2005,18 +2081,22 @@ static ssize_t set_beep(struct device *dev, struct device_attribute *attr, int bitnr = to_sensor_dev_attr(attr)->index; struct it87_data *data = dev_get_drvdata(dev); long val; + int err; if (kstrtol(buf, 10, &val) < 0 || (val != 0 && val != 1)) return -EINVAL; - mutex_lock(&data->update_lock); + err = it87_lock(data); + if (err) + return err; + data->beeps = it87_read_value(data, IT87_REG_BEEP_ENABLE); if (val) data->beeps |= BIT(bitnr); else data->beeps &= ~BIT(bitnr); it87_write_value(data, IT87_REG_BEEP_ENABLE, data->beeps); - mutex_unlock(&data->update_lock); + it87_unlock(data); return count; } @@ -3179,6 +3259,7 @@ static int it87_probe(struct platform_device *pdev) struct it87_sio_data *sio_data = dev_get_platdata(dev); int enable_pwm_interface; struct device *hwmon_dev; + int err; res = platform_get_resource(pdev, IORESOURCE_IO, 0); if (!devm_request_region(&pdev->dev, res->start, IT87_EC_EXTENT, @@ -3224,15 +3305,21 @@ static int it87_probe(struct platform_device *pdev) break; } - /* Now, we do the remaining detection. */ - if ((it87_read_value(data, IT87_REG_CONFIG) & 0x80) || - it87_read_value(data, IT87_REG_CHIPID) != 0x90) - return -ENODEV; - platform_set_drvdata(pdev, data); mutex_init(&data->update_lock); + err = smbus_disable(data); + if (err) + return err; + + /* Now, we do the remaining detection. */ + if ((it87_read_value(data, IT87_REG_CONFIG) & 0x80) || + it87_read_value(data, IT87_REG_CHIPID) != 0x90) { + smbus_enable(data); + return -ENODEV; + } + /* Check PWM configuration */ enable_pwm_interface = it87_check_pwm(dev); if (!enable_pwm_interface) @@ -3293,6 +3380,8 @@ static int it87_probe(struct platform_device *pdev) /* Initialize the IT87 chip */ it87_init_device(pdev); + smbus_enable(data); + if (!sio_data->skip_vid) { data->has_vid = true; data->vrm = vid_which_vrm(); @@ -3360,7 +3449,7 @@ static int it87_resume(struct device *dev) it87_resume_sio(pdev); - mutex_lock(&data->update_lock); + it87_lock(data); it87_check_pwm(dev); it87_check_limit_regs(data); @@ -3373,7 +3462,7 @@ static int it87_resume(struct device *dev) /* force update */ data->valid = false; - mutex_unlock(&data->update_lock); + it87_unlock(data); it87_update_device(dev); -- 2.7.4