From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: From: Guenter Roeck To: Jean Delvare Cc: Nishanth Menon , linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, Guenter Roeck , Mark Brown Subject: [PATCH v2 5/5] hwmon: (tmp102) Convert to use regmap, and drop local cache Date: Sat, 25 Jun 2016 19:40:25 -0700 Message-Id: <1466908825-14222-5-git-send-email-linux@roeck-us.net> In-Reply-To: <1466908825-14222-1-git-send-email-linux@roeck-us.net> References: <1466908825-14222-1-git-send-email-linux@roeck-us.net> List-ID: By concerting the driver to regmap, we can use regmap to cache non-volatile registers. Stop caching the temperature register; while potentially reading it more often can result in reading it more often than necessary, this is offset by the gain due to not re-reading the limit registers. Cc: Mark Brown Signed-off-by: Guenter Roeck --- v2: Set use_single_rw to indicate that the chip can not perform read operations crossing register boundaries. Use REGCACHE_RBTREE instead REGCACHE_FLAT. REGCACHE_FLAT does not initialize the cache from the chip unless num_reg_defaults_raw is provided. If it is provided without actual cache values, it complains with 'No cache defaults, reading back from HW'. REGCACHE_RBTREE automatically initializes register values from the chip if no defaults are provided, and does not complain about it. Note: I'll drop the Cc: to Mark later. drivers/hwmon/tmp102.c | 156 +++++++++++++++++++++++++------------------------ 1 file changed, 79 insertions(+), 77 deletions(-) diff --git a/drivers/hwmon/tmp102.c b/drivers/hwmon/tmp102.c index 487b4ef5992c..e4a2314a2c49 100644 --- a/drivers/hwmon/tmp102.c +++ b/drivers/hwmon/tmp102.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include @@ -61,13 +62,9 @@ #define CONVERSION_TIME_MS 35 /* in milli-seconds */ struct tmp102 { - struct i2c_client *client; - struct mutex lock; + struct regmap *regmap; u16 config_orig; - unsigned long last_update; unsigned long ready_time; - bool valid; - int temp[3]; }; /* convert left adjusted 13-bit TMP102 register value to milliCelsius */ @@ -82,16 +79,11 @@ static inline u16 tmp102_mC_to_reg(int val) return (val * 128) / 1000; } -static const u8 tmp102_reg[] = { - TMP102_TEMP_REG, - TMP102_TLOW_REG, - TMP102_THIGH_REG, -}; - -static struct tmp102 *tmp102_update_device(struct device *dev) +static int tmp102_read_temp(void *dev, int *temp) { struct tmp102 *tmp102 = dev_get_drvdata(dev); - struct i2c_client *client = tmp102->client; + unsigned int reg; + int ret; /* Is it too early to return a conversion ? */ if (time_before(jiffies, tmp102->ready_time)) { @@ -100,28 +92,11 @@ static struct tmp102 *tmp102_update_device(struct device *dev) msleep(jiffies_to_msecs(sleeptime)); } - mutex_lock(&tmp102->lock); - if (!tmp102->valid || - time_after(jiffies, tmp102->last_update + HZ / 3)) { - int i; - for (i = 0; i < ARRAY_SIZE(tmp102->temp); ++i) { - int status = i2c_smbus_read_word_swapped(client, - tmp102_reg[i]); - if (status > -1) - tmp102->temp[i] = tmp102_reg_to_mC(status); - } - tmp102->last_update = jiffies; - tmp102->valid = true; - } - mutex_unlock(&tmp102->lock); - return tmp102; -} - -static int tmp102_read_temp(void *dev, int *temp) -{ - struct tmp102 *tmp102 = tmp102_update_device(dev); + ret = regmap_read(tmp102->regmap, TMP102_TEMP_REG, ®); + if (ret < 0) + return ret; - *temp = tmp102->temp[0]; + *temp = tmp102_reg_to_mC(reg); return 0; } @@ -131,9 +106,24 @@ static ssize_t tmp102_show_temp(struct device *dev, char *buf) { struct sensor_device_attribute *sda = to_sensor_dev_attr(attr); - struct tmp102 *tmp102 = tmp102_update_device(dev); + struct tmp102 *tmp102 = dev_get_drvdata(dev); + int regaddr = sda->index; + unsigned int reg; + int err; + + /* Is it too early to return a conversion ? */ + if (regaddr == TMP102_TEMP_REG && + time_before(jiffies, tmp102->ready_time)) { + unsigned long sleeptime = tmp102->ready_time - jiffies; + + msleep(jiffies_to_msecs(sleeptime)); + } + + err = regmap_read(tmp102->regmap, regaddr, ®); + if (err < 0) + return err; - return sprintf(buf, "%d\n", tmp102->temp[sda->index]); + return sprintf(buf, "%d\n", tmp102_reg_to_mC(reg)); } static ssize_t tmp102_set_temp(struct device *dev, @@ -142,29 +132,26 @@ static ssize_t tmp102_set_temp(struct device *dev, { struct sensor_device_attribute *sda = to_sensor_dev_attr(attr); struct tmp102 *tmp102 = dev_get_drvdata(dev); - struct i2c_client *client = tmp102->client; + int reg = sda->index; long val; - int status; + int err; if (kstrtol(buf, 10, &val) < 0) return -EINVAL; val = clamp_val(val, -256000, 255000); - mutex_lock(&tmp102->lock); - tmp102->temp[sda->index] = val; - status = i2c_smbus_write_word_swapped(client, tmp102_reg[sda->index], - tmp102_mC_to_reg(val)); - mutex_unlock(&tmp102->lock); - return status ? : count; + err = regmap_write(tmp102->regmap, reg, tmp102_mC_to_reg(val)); + return err ? : count; } -static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL , 0); +static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, tmp102_show_temp, NULL, + TMP102_TEMP_REG); static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO, tmp102_show_temp, - tmp102_set_temp, 1); + tmp102_set_temp, TMP102_TLOW_REG); static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, tmp102_show_temp, - tmp102_set_temp, 2); + tmp102_set_temp, TMP102_THIGH_REG); static struct attribute *tmp102_attrs[] = { &sensor_dev_attr_temp1_input.dev_attr.attr, @@ -181,19 +168,39 @@ static const struct thermal_zone_of_device_ops tmp102_of_thermal_ops = { static void tmp102_restore_config(void *data) { struct tmp102 *tmp102 = data; - struct i2c_client *client = tmp102->client; - i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, - tmp102->config_orig); + regmap_write(tmp102->regmap, TMP102_CONF_REG, tmp102->config_orig); +} + +static bool tmp102_is_writeable_reg(struct device *dev, unsigned int reg) +{ + return reg != TMP102_TEMP_REG; +} + +static bool tmp102_is_volatile_reg(struct device *dev, unsigned int reg) +{ + return reg == TMP102_TEMP_REG; } +static const struct regmap_config tmp102_regmap_config = { + .reg_bits = 8, + .val_bits = 16, + .max_register = TMP102_THIGH_REG, + .writeable_reg = tmp102_is_writeable_reg, + .volatile_reg = tmp102_is_volatile_reg, + .val_format_endian = REGMAP_ENDIAN_BIG, + .cache_type = REGCACHE_RBTREE, + .use_single_rw = true, +}; + static int tmp102_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct device *dev = &client->dev; struct device *hwmon_dev; struct tmp102 *tmp102; - int status; + unsigned int regval; + int err; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) { @@ -207,35 +214,36 @@ static int tmp102_probe(struct i2c_client *client, return -ENOMEM; i2c_set_clientdata(client, tmp102); - tmp102->client = client; - status = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG); - if (status < 0) { + tmp102->regmap = devm_regmap_init_i2c(client, &tmp102_regmap_config); + if (IS_ERR(tmp102->regmap)) + return PTR_ERR(tmp102->regmap); + + err = regmap_read(tmp102->regmap, TMP102_CONF_REG, ®val); + if (err < 0) { dev_err(dev, "error reading config register\n"); - return status; + return err; } - if ((status & ~TMP102_CONFREG_MASK) != + if ((regval & ~TMP102_CONFREG_MASK) != (TMP102_CONF_R0 | TMP102_CONF_R1)) { dev_err(dev, "unexpected config register value\n"); return -ENODEV; } - tmp102->config_orig = status; + tmp102->config_orig = regval; devm_add_action(dev, tmp102_restore_config, tmp102); - status &= ~TMP102_CONFIG_CLEAR; - status |= TMP102_CONFIG_SET; + regval &= ~TMP102_CONFIG_CLEAR; + regval |= TMP102_CONFIG_SET; - status = i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, status); - if (status < 0) { + err = regmap_write(tmp102->regmap, TMP102_CONF_REG, regval); + if (err < 0) { dev_err(dev, "error writing config register\n"); - return status; + return err; } - mutex_init(&tmp102->lock); - tmp102->ready_time = jiffies; if (tmp102->config_orig & TMP102_CONF_SD) { /* @@ -264,30 +272,24 @@ static int tmp102_probe(struct i2c_client *client, static int tmp102_suspend(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); - int config; - - config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG); - if (config < 0) - return config; + struct tmp102 *tmp102 = i2c_get_clientdata(client); - config |= TMP102_CONF_SD; - return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config); + return regmap_update_bits(tmp102->regmap, TMP102_CONF_REG, + TMP102_CONF_SD, TMP102_CONF_SD); } static int tmp102_resume(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct tmp102 *tmp102 = i2c_get_clientdata(client); - int config; + int err; - config = i2c_smbus_read_word_swapped(client, TMP102_CONF_REG); - if (config < 0) - return config; + err = regmap_update_bits(tmp102->regmap, TMP102_CONF_REG, + TMP102_CONF_SD, 0); tmp102->ready_time = jiffies + msecs_to_jiffies(CONVERSION_TIME_MS); - config &= ~TMP102_CONF_SD; - return i2c_smbus_write_word_swapped(client, TMP102_CONF_REG, config); + return err; } #endif /* CONFIG_PM */ -- 2.5.0