From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-path: Received: from mail-pg0-f65.google.com ([74.125.83.65]:55751 "EHLO mail-pg0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752196AbdKJOt0 (ORCPT ); Fri, 10 Nov 2017 09:49:26 -0500 Subject: Re: [PATCH v3 2/3] drivers: hwmon: Add W83773G driver To: Lei YU , Mark Rutland , Jean Delvare , Jonathan Corbet , Jiri Kosina Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, Joel Stanley , Andrew Jeffery References: <1510211341-17415-1-git-send-email-mine260309@gmail.com> <1510211341-17415-3-git-send-email-mine260309@gmail.com> From: Guenter Roeck Message-ID: <2747fc2e-0120-cc14-991e-3f5baa4a0780@roeck-us.net> Date: Fri, 10 Nov 2017 06:49:23 -0800 MIME-Version: 1.0 In-Reply-To: <1510211341-17415-3-git-send-email-mine260309@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-hwmon-owner@vger.kernel.org List-Id: linux-hwmon@vger.kernel.org On 11/08/2017 11:09 PM, Lei YU wrote: > Nuvoton W83773G is a hardware monitor IC providing one local > temperature and two remote temperature sensors. > > Signed-off-by: Lei YU Nicely done. Couple of nitpicks left. Thanks! Guenter > --- > v2: > - Rewrite the driver using regmap > - Add offset and update_interval > v3: > - Use devm_hwmon_device_register_with_info() with is_visible/read/write > functions. > --- > drivers/hwmon/Kconfig | 10 ++ > drivers/hwmon/Makefile | 1 + > drivers/hwmon/w83773g.c | 348 ++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 359 insertions(+) > create mode 100644 drivers/hwmon/w83773g.c > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index d654314..11c6248 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -1710,6 +1710,16 @@ config SENSORS_VT8231 > This driver can also be built as a module. If so, the module > will be called vt8231. > > +config SENSORS_W83773G > + tristate "Nuvoton W83773G" > + depends on I2C > + help > + If you say yes here you get support for the Nuvoton W83773G hardware > + monitoring chip. > + > + This driver can also be built as a module. If so, the module > + will be called w83773g. > + > config SENSORS_W83781D > tristate "Winbond W83781D, W83782D, W83783S, Asus AS99127F" > depends on I2C > diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile > index c84d978..0649ad8 100644 > --- a/drivers/hwmon/Makefile > +++ b/drivers/hwmon/Makefile > @@ -13,6 +13,7 @@ obj-$(CONFIG_SENSORS_ATK0110) += asus_atk0110.o > # asb100, then w83781d go first, as they can override other drivers' addresses. > obj-$(CONFIG_SENSORS_ASB100) += asb100.o > obj-$(CONFIG_SENSORS_W83627HF) += w83627hf.o > +obj-$(CONFIG_SENSORS_W83773G) += w83773g.o > obj-$(CONFIG_SENSORS_W83792D) += w83792d.o > obj-$(CONFIG_SENSORS_W83793) += w83793.o > obj-$(CONFIG_SENSORS_W83795) += w83795.o > diff --git a/drivers/hwmon/w83773g.c b/drivers/hwmon/w83773g.c > new file mode 100644 > index 0000000..58ac45b > --- /dev/null > +++ b/drivers/hwmon/w83773g.c > @@ -0,0 +1,348 @@ > +/* > + * Copyright (C) 2017 IBM Corp. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * Driver for the Nuvoton W83773G SMBus temperature sensor IC. > + * Supported models: W83773G > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* Addresses to scan */ > +static const unsigned short normal_i2c[] = { 0x4c, 0x4d, I2C_CLIENT_END }; > + > +/* W83773 has 3 channels */ > +#define W83773_CHANNELS 3 > + > +/* The W83773 registers */ > +#define W83773_CONVERSION_RATE_REG_READ 0x04 > +#define W83773_CONVERSION_RATE_REG_WRITE 0x0A > +#define W83773_MANUFACTURER_ID_REG 0xFE > +#define W83773_LOCAL_TEMP 0x00 > + > +static const u8 W83773_STATUS[2] = { 0x02, 0x17 }; > + > +static const u8 W83773_TEMP_LSB[2] = { 0x10, 0x25 }; > +static const u8 W83773_TEMP_MSB[2] = { 0x01, 0x24 }; > + > +static const u8 W83773_OFFSET_LSB[2] = { 0x12, 0x16 }; > +static const u8 W83773_OFFSET_MSB[2] = { 0x11, 0x15 }; > + > +/* this is the number of sensors in the device */ > +static const struct i2c_device_id w83773_id[] = { > + { "w83773g" }, > + { } > +}; > + > +MODULE_DEVICE_TABLE(i2c, w83773_id); > + > +static const struct of_device_id w83773_of_match[] = { > + { > + .compatible = "nuvoton,w83773g" > + }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, w83773_of_match); > + > +static inline long temp_of_local(s8 reg) > +{ > + return reg * 1000; > +} > + > +static inline long temp_of_remote(s8 hb, u8 lb) > +{ > + return (hb << 3 | lb >> 5) * 125; > +} > + > +static int get_local_temp(struct regmap *regmap, long *val) > +{ > + unsigned int regval; > + int ret; > + > + ret = regmap_read(regmap, W83773_LOCAL_TEMP, ®val); > + if (ret < 0) > + return ret; > + > + *val = temp_of_local(regval); > + return 0; > +} > + > +static int get_remote_temp(struct regmap *regmap, int index, long *val) > +{ > + unsigned int regval_high; > + unsigned int regval_low; > + int ret; > + > + ret = regmap_read(regmap, W83773_TEMP_MSB[index], ®val_high); > + if (ret < 0) > + return ret; > + > + ret = regmap_read(regmap, W83773_TEMP_LSB[index], ®val_low); > + if (ret < 0) > + return ret; > + > + *val = temp_of_remote(regval_high, regval_low); > + return 0; > +} > + > +static int get_fault(struct regmap *regmap, int index, long *val) > +{ > + unsigned int regval; > + int ret; > + > + ret = regmap_read(regmap, W83773_STATUS[index], ®val); > + Drop the empty line please. > + if (ret < 0) > + return ret; > + > + *val = (u8)regval & 0x04 >> 2; > + return 0; > +} > + > +static int get_offset(struct regmap *regmap, int index, long *val) > +{ > + unsigned int regval_high; > + unsigned int regval_low; > + int ret; > + > + ret = regmap_read(regmap, W83773_OFFSET_MSB[index], ®val_high); > + if (ret < 0) > + return ret; > + > + ret = regmap_read(regmap, W83773_OFFSET_LSB[index], ®val_low); > + if (ret < 0) > + return ret; > + > + *val = temp_of_remote(regval_high, regval_low); > + return 0; > +} > + > +static int set_offset(struct regmap *regmap, int index, long val) > +{ > + int ret; > + u8 high_byte; > + u8 low_byte; > + > + val = clamp_val(val, -127825, 127825); > + /* offset value equals to (high_byte << 3 | low_byte >> 5) * 125 */ > + val /= 125; > + high_byte = val >> 3; > + low_byte = (val & 0x07) << 5; > + > + ret = regmap_write(regmap, W83773_OFFSET_MSB[index], high_byte); > + if (ret < 0) > + return ret; > + > + ret = regmap_write(regmap, W83773_OFFSET_LSB[index], low_byte); > + if (ret < 0) > + return ret; > + > + return 0; For the second call, return regmap_write(regmap, W83773_OFFSET_LSB[index], low_byte); > +} > + > +static int get_update_interval(struct regmap *regmap, long *val) > +{ > + unsigned int regval; > + int ret; > + > + ret = regmap_read(regmap, W83773_CONVERSION_RATE_REG_READ, ®val); > + if (ret < 0) > + return ret; > + > + *val = 16000 >> regval; > + return 0; > +} > + > +static int set_update_interval(struct regmap *regmap, long val) > +{ > + int ret; > + int rate; > + > + if (val <= 0) > + return -EINVAL; > + Not really needed since you are clamping below. For consistency I would suggest to drop it (otherwise 0 returns -EINVAL, 1 translates to 62). > + /* > + * For valid rates, interval can be calculated as > + * interval = (1 << (8 - rate)) * 62.5; > + * Rounded rate is therefore > + * rate = 8 - __fls(interval * 8 / (62.5 * 7)); > + * Use clamp_val() to avoid overflows, and to ensure valid input > + * for __fls. > + */ > + val = clamp_val(val, 62, 16000) * 10; > + rate = 8 - __fls((val * 8 / (625 * 7))); > + ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, rate); > + if (ret < 0) > + return ret; > + return 0; just return regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, rate); > +} > + > +static int w83773_read(struct device *dev, enum hwmon_sensor_types type, > + u32 attr, int channel, long *val) > +{ > + struct regmap *regmap = dev_get_drvdata(dev); > + > + if (type == hwmon_chip) { > + if (attr == hwmon_chip_update_interval) > + return get_update_interval(regmap, val); > + else else not needed after return > + return -EOPNOTSUPP; > + } > + > + switch (attr) { > + case hwmon_temp_input: > + if (channel == 0) > + return get_local_temp(regmap, val); > + else else not needed after return > + return get_remote_temp(regmap, channel - 1, val); > + case hwmon_temp_fault: > + return get_fault(regmap, channel - 1, val); > + case hwmon_temp_offset: > + return get_offset(regmap, channel - 1, val); > + default: > + return -EOPNOTSUPP; > + } > +} > + > +static int w83773_write(struct device *dev, enum hwmon_sensor_types type, > + u32 attr, int channel, long val) > +{ > + struct regmap *regmap = dev_get_drvdata(dev); > + > + if (type == hwmon_chip && attr == hwmon_chip_update_interval) > + return set_update_interval(regmap, val); > + > + if (type == hwmon_temp && attr == hwmon_temp_offset) > + return set_offset(regmap, channel - 1, val); > + > + return -EOPNOTSUPP; > +} > + > +static umode_t w83773_is_visible(const void *data, enum hwmon_sensor_types type, > + u32 attr, int channel) > +{ > + switch (type) { > + case hwmon_chip: > + switch (attr) { > + case hwmon_chip_update_interval: > + return 0644; > + } > + break; > + case hwmon_temp: > + switch (attr) { > + case hwmon_temp_input: > + return 0444; > + case hwmon_temp_fault: The above case statements can be combined. > + return 0444; > + case hwmon_temp_offset: > + return 0644; Wonder if static analyzers complain here and above because of the missing default: case. Any idea ? > + } > + break; > + default: > + break; > + } > + return 0; > +} > + > +static const u32 w83773_chip_config[] = { > + HWMON_C_REGISTER_TZ | HWMON_C_UPDATE_INTERVAL, > + 0 > +}; > + > +static const struct hwmon_channel_info w83773_chip = { > + .type = hwmon_chip, > + .config = w83773_chip_config, > +}; > + > +static const u32 w83773_temp_config[] = { > + HWMON_T_INPUT, > + HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_OFFSET, > + HWMON_T_INPUT | HWMON_T_FAULT | HWMON_T_OFFSET, > + 0 > +}; > + > +static const struct hwmon_channel_info w83773_temp = { > + .type = hwmon_temp, > + .config = w83773_temp_config, > +}; > + > +static const struct hwmon_channel_info *w83773_info[] = { > + &w83773_chip, > + &w83773_temp, > + NULL > +}; > + > +static const struct hwmon_ops w83773_ops = { > + .is_visible = w83773_is_visible, > + .read = w83773_read, > + .write = w83773_write, > +}; > + > +static const struct hwmon_chip_info w83773_chip_info = { > + .ops = &w83773_ops, > + .info = w83773_info, > +}; > + > +static const struct regmap_config w83773_regmap_config = { > + .reg_bits = 8, > + .val_bits = 8, > +}; > + > +static int w83773_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct device *dev = &client->dev; > + struct device *hwmon_dev; > + struct regmap *regmap; > + int ret; > + > + regmap = devm_regmap_init_i2c(client, &w83773_regmap_config); > + if (IS_ERR(regmap)) { > + dev_err(dev, "failed to allocate register map\n"); > + return PTR_ERR(regmap); > + } > + > + /* Set the conversion rate to 2 Hz */ > + ret = regmap_write(regmap, W83773_CONVERSION_RATE_REG_WRITE, 0x05); > + if (ret < 0) { > + dev_err(&client->dev, "error writing config rate register\n"); > + return ret; > + } > + > + i2c_set_clientdata(client, regmap); > + > + hwmon_dev = devm_hwmon_device_register_with_info(dev, > + client->name, > + regmap, > + &w83773_chip_info, > + NULL); > + return PTR_ERR_OR_ZERO(hwmon_dev); > +} > + > +static struct i2c_driver w83773_driver = { > + .class = I2C_CLASS_HWMON, > + .driver = { > + .name = "w83773g", > + .of_match_table = of_match_ptr(w83773_of_match), > + }, > + .probe = w83773_probe, > + .id_table = w83773_id, > + .address_list = normal_i2c, address_list is only used if there is a detect function, so you can drop it. > +}; > + > +module_i2c_driver(w83773_driver); > + > +MODULE_AUTHOR("Lei YU "); > +MODULE_DESCRIPTION("W83773G temperature sensor driver"); > +MODULE_LICENSE("GPL"); >