Re: [PATCH v2 1/2] hwmon: (ads7828) driver cleanup

Guenter Roeck
2012-10-02T01:06:34Z

On Mon, Oct 01, 2012 at 07:16:23PM -0400, Vivien Didelot wrote:
> * Remove unused macros;
> * Point to the documentation;
> * Coding Style fixes (Kernel Doc, spacing);
> * Move driver declaration to avoid adding function prototypes.
>
> Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>

Hi Vivien,

> ---
> drivers/hwmon/ads7828.c | 91 +++++++++++++++++++++++--------------------------
> 1 file changed, 43 insertions(+), 48 deletions(-)
>
> diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c
> index bf3fdf4..fb3010d 100644
> --- a/drivers/hwmon/ads7828.c
> +++ b/drivers/hwmon/ads7828.c
> @@ -6,7 +6,7 @@
> *
> * Written by Steve Hardy <shardy@redhat.com>
> *
> - * Datasheet available at: http://focus.ti.com/lit/ds/symlink/ads7828.pdf
> + * For further information, see the Documentation/hwmon/ads7828 file.
> *
> * 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
> @@ -34,14 +34,12 @@
> #include <linux/mutex.h>
>
> /* The ADS7828 registers */
> -#define ADS7828_NCH 8 /* 8 channels of 12-bit A-D supported */
> -#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
> -#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
> -#define ADS7828_CMD_PD0 0x0 /* Power Down between A-D conversions */
> -#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A-D ON */
> -#define ADS7828_CMD_PD2 0x08 /* Internal ref ON && A-D OFF */
> -#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A-D ON */
> -#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
> +#define ADS7828_NCH 8 /* 8 channels supported */
> +#define ADS7828_CMD_SD_SE 0x80 /* Single ended inputs */
> +#define ADS7828_CMD_SD_DIFF 0x00 /* Differential inputs */
> +#define ADS7828_CMD_PD1 0x04 /* Internal ref OFF && A/D ON */
> +#define ADS7828_CMD_PD3 0x0C /* Internal ref ON && A/D ON */
> +#define ADS7828_INT_VREF_MV 2500 /* Internal vref is 2.5V, 2500mV */
>
> /* Addresses to scan */
> static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b,
> @@ -59,25 +57,26 @@ module_param(vref_mv, int, S_IRUGO);
> static u8 ads7828_cmd_byte; /* cmd byte without channel bits */
> static unsigned int ads7828_lsb_resol; /* resolution of the ADC sample lsb */
>
> -/* Each client has this additional data */
> +/**
> + * struct ads7828_data - client specific data
> + * @hwmon_dev: The hwmon device.
> + * @update_lock: Mutex protecting updates.
> + * @valid: Validity flag.
> + * @last_updated: Last updated time (in jiffies).
> + * @adc_input: ADS7828_NCH samples.
> + */
This isn't really an externally visible API, so I wonder if it provides value to
document it this way. No strong opinion, just wondering.

> struct ads7828_data {
> struct device *hwmon_dev;
> - struct mutex update_lock; /* mutex protect updates */
> - char valid; /* !=0 if following fields are valid */
> - unsigned long last_updated; /* In jiffies */
> - u16 adc_input[ADS7828_NCH]; /* ADS7828_NCH 12-bit samples */
> + struct mutex update_lock;
> + char valid;
> + unsigned long last_updated;
> + u16 adc_input[ADS7828_NCH];
> };
>
> -/* Function declaration - necessary due to function dependencies */
> -static int ads7828_detect(struct i2c_client *client,
> - struct i2c_board_info *info);
> -static int ads7828_probe(struct i2c_client *client,
> - const struct i2c_device_id *id);
> -
> static inline u8 channel_cmd_byte(int ch)
> {
> /* cmd byte C2,C1,C0 - see datasheet */
> - u8 cmd = (((ch>>1) | (ch&0x01)<<2)<<4);
> + u8 cmd = (((ch >> 1) | (ch & 0x01) << 2) << 4);
> cmd |= ads7828_cmd_byte;
> return cmd;
> }
> @@ -120,9 +119,8 @@ static ssize_t show_in(struct device *dev, struct device_attribute *da,
> ads7828_lsb_resol)/1000);

Can you fix this one as well since you are at it ? There is another one in sensors_ads7828_init().
[ Wonder why checkpatch doesn't complain about it ]

> }
>
> -#define in_reg(offset)\
> -static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in,\
> - NULL, offset)
> +#define in_reg(offset) \
> +static SENSOR_DEVICE_ATTR(in##offset##_input, S_IRUGO, show_in, NULL, offset)
>
This causes a checkpatch error - checkpatch doesn't like the multi-line macros.

> in_reg(0);
> in_reg(1);

Since it seems to be hardly worth it anyway (yes, I know there are 8 of them),
would be great if you can just get rid of the macro and just use
static SENSOR_DEVICE_ATTR(in[1-8]_input, ...)
instead.

> @@ -158,25 +156,6 @@ static int ads7828_remove(struct i2c_client *client)
> return 0;
> }
>
> -static const struct i2c_device_id ads7828_id[] = {
> - { "ads7828", 0 },
> - { }
> -};
> -MODULE_DEVICE_TABLE(i2c, ads7828_id);
> -
> -/* This is the driver that will be inserted */
> -static struct i2c_driver ads7828_driver = {
> - .class = I2C_CLASS_HWMON,
> - .driver = {
> - .name = "ads7828",
> - },
> - .probe = ads7828_probe,
> - .remove = ads7828_remove,
> - .id_table = ads7828_id,
> - .detect = ads7828_detect,
> - .address_list = normal_i2c,
> -};
> -
> /* Return 0 if detection is successful, -ENODEV otherwise */
> static int ads7828_detect(struct i2c_client *client,
> struct i2c_board_info *info)
> @@ -247,13 +226,29 @@ exit:
> return err;
> }
>
> +static const struct i2c_device_id ads7828_ids[] = {
> + { "ads7828", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, ads7828_ids);
> +
> +static struct i2c_driver ads7828_driver = {
> + .class = I2C_CLASS_HWMON,
> + .driver = {
> + .name = "ads7828",
> + },
> + .address_list = normal_i2c,
> + .detect = ads7828_detect,
> + .probe = ads7828_probe,
> + .remove = ads7828_remove,
> + .id_table = ads7828_ids,
> +};
> +
> static int __init sensors_ads7828_init(void)
> {
> /* Initialize the command byte according to module parameters */
> - ads7828_cmd_byte = se_input ?
> - ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
> - ads7828_cmd_byte |= int_vref ?
> - ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
> + ads7828_cmd_byte = se_input ? ADS7828_CMD_SD_SE : ADS7828_CMD_SD_DIFF;
> + ads7828_cmd_byte |= int_vref ? ADS7828_CMD_PD3 : ADS7828_CMD_PD1;
>
> /* Calculate the LSB resolution */
> ads7828_lsb_resol = (vref_mv*1000)/4096;
> @@ -267,7 +262,7 @@ static void __exit sensors_ads7828_exit(void)
> }
>
> MODULE_AUTHOR("Steve Hardy <shardy@redhat.com>");
> -MODULE_DESCRIPTION("ADS7828 driver");
> +MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter");
> MODULE_LICENSE("GPL");
>
> module_init(sensors_ads7828_init);
> --
> 1.7.11.4
>
>