Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752449AbaBNRpL (ORCPT ); Fri, 14 Feb 2014 12:45:11 -0500 Received: from mail-pa0-f44.google.com ([209.85.220.44]:59209 "EHLO mail-pa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751692AbaBNRpJ (ORCPT ); Fri, 14 Feb 2014 12:45:09 -0500 Date: Fri, 14 Feb 2014 09:45:05 -0800 From: Guenter Roeck To: Laszlo Papp Cc: jdelvare@suse.de, lm-sensors@lm-sensors.org, lee.jones@linaro.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] hwmon: (max6650) Convert to be a platform driver Message-ID: <20140214174505.GB23195@roeck-us.net> References: <1392369342-11472-1-git-send-email-lpapp@kde.org> <1392369342-11472-3-git-send-email-lpapp@kde.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1392369342-11472-3-git-send-email-lpapp@kde.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Feb 14, 2014 at 09:15:42AM +0000, Laszlo Papp wrote: > The MFD driver has now been added, so this driver is now being adopted to be a > subdevice driver on top of it. This means, the i2c driver usage is being > converted to platform driver usage all around. > > Signed-off-by: Laszlo Papp > --- > drivers/hwmon/Kconfig | 2 +- > drivers/hwmon/max6650.c | 125 ++++++++++++++++++++++++------------------------ > 2 files changed, 63 insertions(+), 64 deletions(-) > > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 7ed3aa6..fcfe484 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -962,7 +962,7 @@ config SENSORS_MAX6642 > > config SENSORS_MAX6650 > tristate "Maxim MAX6650 sensor chip" > - depends on I2C > + depends on MFD_MAX665X > help > If you say yes here you get support for the MAX6650 / MAX6651 > sensor chips. > diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c > index 162a520..4d79413 100644 > --- a/drivers/hwmon/max6650.c > +++ b/drivers/hwmon/max6650.c > @@ -39,6 +39,9 @@ > #include > #include > #include > +#include > + > +#include 'private' is a somewhat unusual file name in a global include file. Why not just max665x.h ? > > /* > * Insmod parameters > @@ -112,18 +115,19 @@ module_param(clock, int, S_IRUGO); > struct max6650_data { > struct i2c_client *client; client is no longer needed, and all other references to i2c (such as include files) should be removed as well. > const struct attribute_group *groups[3]; > + struct max665x_dev *iodev; The only use of this variable is to dereference map. 'struct regmap *map' might thus make more sense here. Also, iodev is not initialized. The first access to iodev->map will result in a null pointer access. > struct mutex update_lock; > int nr_fans; > char valid; /* zero until following fields are valid */ > unsigned long last_updated; /* in jiffies */ > > /* register values */ > - u8 speed; > - u8 config; > - u8 tach[4]; > - u8 count; > - u8 dac; > - u8 alarm; > + int speed; > + int config; > + int tach[4]; > + int count; > + int dac; > + int alarm; > }; > > static const u8 tach_reg[] = { > @@ -136,31 +140,29 @@ static const u8 tach_reg[] = { > static struct max6650_data *max6650_update_device(struct device *dev) > { > struct max6650_data *data = dev_get_drvdata(dev); > - struct i2c_client *client = data->client; > + struct regmap *map = data->iodev->map; > int i; > + int alarm; > > mutex_lock(&data->update_lock); > > if (time_after(jiffies, data->last_updated + HZ) || !data->valid) { > - data->speed = i2c_smbus_read_byte_data(client, > - MAX6650_REG_SPEED); > - data->config = i2c_smbus_read_byte_data(client, > - MAX6650_REG_CONFIG); > + regmap_read(map, MAX6650_REG_SPEED, &data->speed); > + regmap_read(map, MAX6650_REG_CONFIG, &data->config); > for (i = 0; i < data->nr_fans; i++) { > - data->tach[i] = i2c_smbus_read_byte_data(client, > - tach_reg[i]); > + data->tach[i] = regmap_read(map, tach_reg[i], > + &data->tach[i]); > } > - data->count = i2c_smbus_read_byte_data(client, > - MAX6650_REG_COUNT); > - data->dac = i2c_smbus_read_byte_data(client, MAX6650_REG_DAC); > + regmap_read(map, MAX6650_REG_COUNT, &data->count); > + regmap_read(map, MAX6650_REG_DAC, &data->dac); > > /* > * Alarms are cleared on read in case the condition that > * caused the alarm is removed. Keep the value latched here > * for providing the register through different alarm files. > */ > - data->alarm |= i2c_smbus_read_byte_data(client, > - MAX6650_REG_ALARM); > + regmap_read(map, MAX6650_REG_ALARM, &alarm); > + data->alarm |= alarm; > > data->last_updated = jiffies; > data->valid = 1; > @@ -256,7 +258,6 @@ static ssize_t set_target(struct device *dev, struct device_attribute *devattr, > const char *buf, size_t count) > { > struct max6650_data *data = dev_get_drvdata(dev); > - struct i2c_client *client = data->client; > int kscale, ktach; > unsigned long rpm; > int err; > @@ -284,7 +285,7 @@ static ssize_t set_target(struct device *dev, struct device_attribute *devattr, > ktach = 255; > data->speed = ktach; > > - i2c_smbus_write_byte_data(client, MAX6650_REG_SPEED, data->speed); > + regmap_write(data->iodev->map, MAX6650_REG_SPEED, data->speed); > > mutex_unlock(&data->update_lock); > > @@ -325,7 +326,6 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr, > const char *buf, size_t count) > { > struct max6650_data *data = dev_get_drvdata(dev); > - struct i2c_client *client = data->client; > unsigned long pwm; > int err; > > @@ -342,7 +342,7 @@ static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr, > else > data->dac = 76 - (76 * pwm)/255; > > - i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac); > + regmap_write(data->iodev->map, MAX6650_REG_DAC, data->dac); > > mutex_unlock(&data->update_lock); > > @@ -371,7 +371,7 @@ static ssize_t set_enable(struct device *dev, struct device_attribute *devattr, > const char *buf, size_t count) > { > struct max6650_data *data = dev_get_drvdata(dev); > - struct i2c_client *client = data->client; > + struct regmap *map = data->iodev->map; > int max6650_modes[3] = {0, 3, 2}; > unsigned long mode; > int err; > @@ -385,11 +385,11 @@ static ssize_t set_enable(struct device *dev, struct device_attribute *devattr, > > mutex_lock(&data->update_lock); > > - data->config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG); > + regmap_read(map, MAX6650_REG_CONFIG, &data->config); > data->config = (data->config & ~MAX6650_CFG_MODE_MASK) > | (max6650_modes[mode] << 4); > > - i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, data->config); > + regmap_write(map, MAX6650_REG_CONFIG, data->config); > > mutex_unlock(&data->update_lock); > > @@ -421,7 +421,6 @@ static ssize_t set_div(struct device *dev, struct device_attribute *devattr, > const char *buf, size_t count) > { > struct max6650_data *data = dev_get_drvdata(dev); > - struct i2c_client *client = data->client; > unsigned long div; > int err; > > @@ -448,7 +447,7 @@ static ssize_t set_div(struct device *dev, struct device_attribute *devattr, > return -EINVAL; > } > > - i2c_smbus_write_byte_data(client, MAX6650_REG_COUNT, data->count); > + regmap_write(data->iodev->map, MAX6650_REG_COUNT, data->count); > mutex_unlock(&data->update_lock); > > return count; > @@ -465,16 +464,15 @@ static ssize_t get_alarm(struct device *dev, struct device_attribute *devattr, > char *buf) > { > struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr); > - struct max6650_data *data = max6650_update_device(dev); > - struct i2c_client *client = data->client; > + struct max6650_data *data = dev_get_drvdata(dev); > int alarm = 0; > > if (data->alarm & attr->index) { > mutex_lock(&data->update_lock); > - alarm = 1; > data->alarm &= ~attr->index; > - data->alarm |= i2c_smbus_read_byte_data(client, > - MAX6650_REG_ALARM); > + regmap_read(data->iodev->map, MAX6650_REG_ALARM, &alarm); > + data->alarm |= alarm; > + alarm = 1; > mutex_unlock(&data->update_lock); > } > > @@ -505,10 +503,11 @@ static umode_t max6650_attrs_visible(struct kobject *kobj, struct attribute *a, > { > struct device *dev = container_of(kobj, struct device, kobj); > struct max6650_data *data = dev_get_drvdata(dev); > - struct i2c_client *client = data->client; > - u8 alarm_en = i2c_smbus_read_byte_data(client, MAX6650_REG_ALARM_EN); > + int alarm_en; > struct device_attribute *devattr; > > + regmap_read(data->iodev->map, MAX6650_REG_ALARM_EN, &alarm_en); > + There is now a difference in handline alarm_en and in general return values from i2c_smbus_read_byte_data vs. regmap_read. alarm_en is no longer initialized if regmap_read() returns an error. It will therefore be necessary to check the return values or pre-initialize the variable. The same applies to all other places where the reeturn value of regmap_read is not checked. > /* > * Hide the alarms that have not been enabled by the firmware > */ > @@ -560,17 +559,17 @@ static const struct attribute_group max6651_group = { > * Real code > */ > > -static int max6650_init_client(struct max6650_data *data, > - struct i2c_client *client) > +static int max6650_init_client(struct platform_device *pdev) > { > - struct device *dev = &client->dev; I had a reason for introducing this variable here and in the probe function. Please don't remove it. > + struct max6650_data *data = platform_get_drvdata(pdev); > + struct regmap *map = data->iodev->map; > int config; > int err = -EIO; > > - config = i2c_smbus_read_byte_data(client, MAX6650_REG_CONFIG); > + regmap_read(map, MAX6650_REG_CONFIG, &config); > > if (config < 0) { > - dev_err(dev, "Error reading config, aborting.\n"); > + dev_err(&pdev->dev, "Error reading config, aborting.\n"); > return err; > } > > @@ -584,11 +583,11 @@ static int max6650_init_client(struct max6650_data *data, > config |= MAX6650_CFG_V12; > break; > default: > - dev_err(dev, "illegal value for fan_voltage (%d)\n", > + dev_err(&pdev->dev, "illegal value for fan_voltage (%d)\n", > fan_voltage); > } > > - dev_info(dev, "Fan voltage is set to %dV.\n", > + dev_info(&pdev->dev, "Fan voltage is set to %dV.\n", > (config & MAX6650_CFG_V12) ? 12 : 5); > > switch (prescaler) { > @@ -614,10 +613,11 @@ static int max6650_init_client(struct max6650_data *data, > | MAX6650_CFG_PRESCALER_16; > break; > default: > - dev_err(dev, "illegal value for prescaler (%d)\n", prescaler); > + dev_err(&pdev->dev, "illegal value for prescaler (%d)\n", > + prescaler); > } > > - dev_info(dev, "Prescaler is set to %d.\n", > + dev_info(&pdev->dev, "Prescaler is set to %d.\n", > 1 << (config & MAX6650_CFG_PRESCALER_MASK)); > > /* > @@ -627,46 +627,45 @@ static int max6650_init_client(struct max6650_data *data, > */ > > if ((config & MAX6650_CFG_MODE_MASK) == MAX6650_CFG_MODE_OFF) { > - dev_dbg(dev, "Change mode to open loop, full off.\n"); > + dev_dbg(&pdev->dev, "Change mode to open loop, full off.\n"); > config = (config & ~MAX6650_CFG_MODE_MASK) > | MAX6650_CFG_MODE_OPEN_LOOP; > - if (i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, 255)) { > - dev_err(dev, "DAC write error, aborting.\n"); > + if (regmap_write(data->iodev->map, MAX6650_REG_DAC, 255) < 0) { > + dev_err(&pdev->dev, "DAC write error, aborting.\n"); > return err; > } > } > > - if (i2c_smbus_write_byte_data(client, MAX6650_REG_CONFIG, config)) { > - dev_err(dev, "Config write error, aborting.\n"); > + if (regmap_write(map, MAX6650_REG_CONFIG, config) < 0) { > + dev_err(&pdev->dev, "Config write error, aborting.\n"); > return err; > } > > data->config = config; > - data->count = i2c_smbus_read_byte_data(client, MAX6650_REG_COUNT); > + regmap_read(map, MAX6650_REG_COUNT, &data->count); > > return 0; > } > > -static int max6650_probe(struct i2c_client *client, > - const struct i2c_device_id *id) > +static int max6650_probe(struct platform_device *pdev) > { > - struct device *dev = &client->dev; > - struct max6650_data *data; > + struct max6650_data *data = platform_get_drvdata(pdev); driver data points to struct max665x_dev *. This should probably be something like struct max665x_dev *iodev = platform_get_drvdata(pdev); as a separate variable. It also needs to be validated to ensure that it is not NULL. > + const struct platform_device_id *id = platform_get_device_id(pdev); > struct device *hwmon_dev; > int err; > > - data = devm_kzalloc(dev, sizeof(struct max6650_data), GFP_KERNEL); > + data = devm_kzalloc(&pdev->dev, sizeof(struct max6650_data), > + GFP_KERNEL); > if (!data) > return -ENOMEM; > > - data->client = client; data->iodev = iodev; or better data->map = iodev->map; is missing. > mutex_init(&data->update_lock); > data->nr_fans = id->driver_data; > > /* > * Initialize the max6650 chip > */ > - err = max6650_init_client(data, client); > + err = max6650_init_client(pdev); > if (err) > return err; > > @@ -675,20 +674,20 @@ static int max6650_probe(struct i2c_client *client, > if (data->nr_fans == 4) > data->groups[1] = &max6651_group; > > - hwmon_dev = devm_hwmon_device_register_with_groups(dev, > - client->name, data, > - data->groups); > + hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev, > + data->client->name, This will crash (client is NULL). You'll have to come up with a scheme to pass the device type from the mfd driver to this one, and use "max6650" and "max6651" as names here. > + data, data->groups); > return PTR_ERR_OR_ZERO(hwmon_dev); > } > > -static const struct i2c_device_id max6650_id[] = { > +static const struct platform_device_id max6650_id[] = { > { "max6650", 1 }, > { "max6651", 4 }, > { } > }; > -MODULE_DEVICE_TABLE(i2c, max6650_id); > +MODULE_DEVICE_TABLE(platform, max6650_id); > > -static struct i2c_driver max6650_driver = { > +static struct platform_driver max6650_driver = { > .driver = { > .name = "max6650", > }, > @@ -696,7 +695,7 @@ static struct i2c_driver max6650_driver = { > .id_table = max6650_id, > }; > > -module_i2c_driver(max6650_driver); > +module_platform_driver(max6650_driver); > > MODULE_AUTHOR("Hans J. Koch"); > MODULE_DESCRIPTION("MAX6650 sensor driver"); > -- > 1.8.5.4 > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/