diff options
author | Jean Delvare <khali@linux-fr.org> | 2010-10-28 20:31:47 +0200 |
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committer | Jean Delvare <khali@endymion.delvare> | 2010-10-28 20:31:47 +0200 |
commit | 01879a855fb6bdb3fb820344a7a145de8a5cdbda (patch) | |
tree | 152e9a958bfdd71692455d18348623b1cbb40929 /drivers/hwmon/w83795.c | |
parent | hwmon: (w83795) Add support for dynamic in0-2 limits (diff) | |
download | linux-01879a855fb6bdb3fb820344a7a145de8a5cdbda.tar.xz linux-01879a855fb6bdb3fb820344a7a145de8a5cdbda.zip |
hwmon: (w83795) Fix PWM duty cycle frequency attributes
The PWM duty cycle frequenty attributes are improperly named
(fanN_div instead of pwmN_div) and contain raw values instead of
actual frequencies. Rename them and fix their contents.
Also improve the logic when the user asks for a new frequency, to
always pick the closest supported frequency. The algorithm could
certainly be optimized, but the operation is infrequent enough that
I don't think it's worth the effort.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to '')
-rw-r--r-- | drivers/hwmon/w83795.c | 90 |
1 files changed, 62 insertions, 28 deletions
diff --git a/drivers/hwmon/w83795.c b/drivers/hwmon/w83795.c index 458fb297f696..58c61f11ed66 100644 --- a/drivers/hwmon/w83795.c +++ b/drivers/hwmon/w83795.c @@ -200,7 +200,6 @@ static const u8 IN_LSB_SHIFT_IDX[][2] = { #define W83795_REG_FCMS2 0x208 #define W83795_REG_TFMR(index) (0x202 + (index)) #define W83795_REG_FOMC 0x20F -#define W83795_REG_FOPFP(index) (0x218 + (index)) #define W83795_REG_TSS(index) (0x209 + (index)) @@ -208,18 +207,13 @@ static const u8 IN_LSB_SHIFT_IDX[][2] = { #define PWM_START 1 #define PWM_NONSTOP 2 #define PWM_STOP_TIME 3 -#define PWM_DIV 4 +#define PWM_FREQ 4 #define W83795_REG_PWM(index, nr) \ (((nr) == 0 ? 0x210 : \ (nr) == 1 ? 0x220 : \ (nr) == 2 ? 0x228 : \ (nr) == 3 ? 0x230 : 0x218) + (index)) -#define W83795_REG_FOPFP_DIV(index) \ - (((index) < 8) ? ((index) + 1) : \ - ((index) == 8) ? 12 : \ - (16 << ((index) - 9))) - #define W83795_REG_FTSH(index) (0x240 + (index) * 2) #define W83795_REG_FTSL(index) (0x241 + (index) * 2) #define W83795_REG_TFTS 0x250 @@ -304,6 +298,50 @@ static inline s8 temp_to_reg(long val, s8 min, s8 max) return SENSORS_LIMIT((val < 0 ? -val : val) / 1000, min, max); } +static const u16 pwm_freq_cksel0[16] = { + 1024, 512, 341, 256, 205, 171, 146, 128, + 85, 64, 32, 16, 8, 4, 2, 1 +}; + +static unsigned int pwm_freq_from_reg(u8 reg, u16 clkin) +{ + unsigned long base_clock; + + if (reg & 0x80) { + base_clock = clkin * 1000 / ((clkin == 48000) ? 384 : 256); + return base_clock / ((reg & 0x7f) + 1); + } else + return pwm_freq_cksel0[reg & 0x0f]; +} + +static u8 pwm_freq_to_reg(unsigned long val, u16 clkin) +{ + unsigned long base_clock; + u8 reg0, reg1; + unsigned long best0, best1; + + /* Best fit for cksel = 0 */ + for (reg0 = 0; reg0 < ARRAY_SIZE(pwm_freq_cksel0) - 1; reg0++) { + if (val > (pwm_freq_cksel0[reg0] + + pwm_freq_cksel0[reg0 + 1]) / 2) + break; + } + if (val < 375) /* cksel = 1 can't beat this */ + return reg0; + best0 = pwm_freq_cksel0[reg0]; + + /* Best fit for cksel = 1 */ + base_clock = clkin * 1000 / ((clkin == 48000) ? 384 : 256); + reg1 = SENSORS_LIMIT(DIV_ROUND_CLOSEST(base_clock, val), 1, 128); + best1 = base_clock / reg1; + reg1 = 0x80 | (reg1 - 1); + + /* Choose the closest one */ + if (abs(val - best0) > abs(val - best1)) + return reg1; + else + return reg0; +} enum chip_types {w83795g, w83795adg}; @@ -343,7 +381,8 @@ struct w83795_data { * no config register, only affected by chip * type */ u8 pwm[8][5]; /* Register value, output, start, non stop, stop - * time, div */ + * time, freq */ + u16 clkin; /* CLKIN frequency in kHz */ u8 pwm_fcms[2]; /* Register value */ u8 pwm_tfmr[6]; /* Register value */ u8 pwm_fomc; /* Register value */ @@ -688,14 +727,14 @@ show_pwm(struct device *dev, struct device_attribute *attr, char *buf) to_sensor_dev_attr_2(attr); int nr = sensor_attr->nr; int index = sensor_attr->index; - u16 val; + unsigned int val; switch (nr) { case PWM_STOP_TIME: val = time_from_reg(data->pwm[index][nr]); break; - case PWM_DIV: - val = W83795_REG_FOPFP_DIV(data->pwm[index][nr] & 0x0f); + case PWM_FREQ: + val = pwm_freq_from_reg(data->pwm[index][nr], data->clkin); break; default: val = data->pwm[index][nr]; @@ -716,7 +755,6 @@ store_pwm(struct device *dev, struct device_attribute *attr, int nr = sensor_attr->nr; int index = sensor_attr->index; unsigned long val; - int i; if (strict_strtoul(buf, 10, &val) < 0) return -EINVAL; @@ -726,28 +764,17 @@ store_pwm(struct device *dev, struct device_attribute *attr, case PWM_STOP_TIME: val = time_to_reg(val); break; - case PWM_DIV: - for (i = 0; i < 16; i++) { - if (W83795_REG_FOPFP_DIV(i) == val) { - val = i; - break; - } - } - if (i >= 16) - goto err_end; - val |= w83795_read(client, W83795_REG_PWM(index, nr)) & 0x80; + case PWM_FREQ: + val = pwm_freq_to_reg(val, data->clkin); break; default: val = SENSORS_LIMIT(val, 0, 0xff); break; } w83795_write(client, W83795_REG_PWM(index, nr), val); - data->pwm[index][nr] = val & 0xff; + data->pwm[index][nr] = val; mutex_unlock(&data->update_lock); return count; -err_end: - mutex_unlock(&data->update_lock); - return -EINVAL; } static ssize_t @@ -1502,8 +1529,8 @@ store_sf_setup(struct device *dev, struct device_attribute *attr, show_pwm, store_pwm, PWM_START, index - 1), \ SENSOR_ATTR_2(pwm##index##_stop_time, S_IWUSR | S_IRUGO, \ show_pwm, store_pwm, PWM_STOP_TIME, index - 1), \ - SENSOR_ATTR_2(fan##index##_div, S_IWUSR | S_IRUGO, \ - show_pwm, store_pwm, PWM_DIV, index - 1), \ + SENSOR_ATTR_2(pwm##index##_freq, S_IWUSR | S_IRUGO, \ + show_pwm, store_pwm, PWM_FREQ, index - 1), \ SENSOR_ATTR_2(pwm##index##_enable, S_IWUSR | S_IRUGO, \ show_pwm_enable, store_pwm_enable, NOT_USED, index - 1), \ SENSOR_ATTR_2(fan##index##_target, S_IWUSR | S_IRUGO, \ @@ -1685,6 +1712,10 @@ static const struct sensor_device_attribute_2 sda_single_files[] = { static void w83795_init_client(struct i2c_client *client) { + struct w83795_data *data = i2c_get_clientdata(client); + static const u16 clkin[4] = { /* in kHz */ + 14318, 24000, 33333, 48000 + }; u8 config; if (reset) @@ -1697,6 +1728,9 @@ static void w83795_init_client(struct i2c_client *client) w83795_write(client, W83795_REG_CONFIG, config | W83795_REG_CONFIG_START); } + + data->clkin = clkin[(config >> 3) & 0x3]; + dev_dbg(&client->dev, "clkin = %u kHz\n", data->clkin); } static int w83795_get_device_id(struct i2c_client *client) |