Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756780Ab2JAV3H (ORCPT ); Mon, 1 Oct 2012 17:29:07 -0400 Received: from mail.active-venture.com ([67.228.131.205]:57720 "EHLO mail.active-venture.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751204Ab2JAV3F (ORCPT ); Mon, 1 Oct 2012 17:29:05 -0400 X-Originating-IP: 108.223.40.66 Date: Mon, 1 Oct 2012 14:29:40 -0700 From: Guenter Roeck To: Vivien Didelot Cc: lm-sensors@lm-sensors.org, Guillaume Roguez , Jean Delvare , linux-kernel@vger.kernel.org, Steve Hardy Subject: Re: [PATCH] hwmon: (ads7828) add support for ADS7830 Message-ID: <20121001212940.GA30936@roeck-us.net> References: <1349124260-28656-1-git-send-email-vivien.didelot@savoirfairelinux.com> <197551023.728862.1349125751841.JavaMail.root@mail.savoirfairelinux.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <197551023.728862.1349125751841.JavaMail.root@mail.savoirfairelinux.com> 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 Content-Length: 12538 Lines: 343 On Mon, Oct 01, 2012 at 05:09:11PM -0400, Vivien Didelot wrote: > Oops, I used the wrong address for Guenter. Here we go. > Hi Vivien, I got it anyway, through the mailing list... > Thanks, > Vivien > > ----- Mail original ----- > De: "Vivien Didelot" > ?: lm-sensors@lm-sensors.org > Cc: "Guillaume Roguez" , "Guenter Roeck" , "Jean Delvare" , linux-kernel@vger.kernel.org, "Steve Hardy" , "Vivien Didelot" > Envoy?: Lundi 1 Octobre 2012 16:44:20 > Objet: [PATCH] hwmon: (ads7828) add support for ADS7830 > > From: Guillaume Roguez > > The ADS7830 is almost the same chip, except that it does 8-bit sampling. > This patch extends the ads7828 driver to support this device. > > Signed-off-by: Guillaume Roguez > > Also clean the driver a bit by removing unused macros, and moving > the driver declaration to avoid some function prototypes. > One change per patch, please. Please handle the cleanup with a separate patch. Other than that, not sure if the changes warrant a copyright, and you can not add a copyright for a third person (or replace a "Written by" statement with a copyright). Thanks, Guenter > Signed-off-by: Vivien Didelot > --- > Documentation/hwmon/ads7828 | 12 +++- > drivers/hwmon/Kconfig | 7 ++- > drivers/hwmon/ads7828.c | 137 +++++++++++++++++++++++++------------------- > 3 files changed, 93 insertions(+), 63 deletions(-) > > diff --git a/Documentation/hwmon/ads7828 b/Documentation/hwmon/ads7828 > index 2bbebe6..4366a87 100644 > --- a/Documentation/hwmon/ads7828 > +++ b/Documentation/hwmon/ads7828 > @@ -8,8 +8,15 @@ Supported chips: > Datasheet: Publicly available at the Texas Instruments website : > http://focus.ti.com/lit/ds/symlink/ads7828.pdf > > + * Texas Instruments ADS7830 > + Prefix: 'ads7830' > + Addresses scanned: I2C 0x48, 0x49, 0x4a, 0x4b > + Datasheet: Publicly available at the Texas Instruments website: > + http://focus.ti.com/lit/ds/symlink/ads7830.pdf > + > Authors: > Steve Hardy > + Guillaume Roguez > > Module Parameters > ----------------- > @@ -24,9 +31,10 @@ Module Parameters > Description > ----------- > > -This driver implements support for the Texas Instruments ADS7828. > +This driver implements support for the Texas Instruments ADS7828, and ADS7830. > > -This device is a 12-bit 8-channel A-D converter. > +The ADS7828 device is a 12-bit 8-channel A/D converter, while the ADS7830 does > +8-bit sampling. > > It can operate in single ended mode (8 +ve inputs) or in differential mode, > where 4 differential pairs can be measured. > diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig > index 83e3e9d..960c8c5 100644 > --- a/drivers/hwmon/Kconfig > +++ b/drivers/hwmon/Kconfig > @@ -1060,11 +1060,12 @@ config SENSORS_ADS1015 > will be called ads1015. > > config SENSORS_ADS7828 > - tristate "Texas Instruments ADS7828" > + tristate "Texas Instruments ADS7828 and compatibles" > depends on I2C > help > - If you say yes here you get support for Texas Instruments ADS7828 > - 12-bit 8-channel ADC device. > + If you say yes here you get support for Texas Instruments ADS7828 and > + ADS7830 8-channel A/D converters. ADS7828 resolution is 12-bit, while > + it is 8-bit on ADS7830. > > This driver can also be built as a module. If so, the module > will be called ads7828. > diff --git a/drivers/hwmon/ads7828.c b/drivers/hwmon/ads7828.c > index bf3fdf4..58f28ea 100644 > --- a/drivers/hwmon/ads7828.c > +++ b/drivers/hwmon/ads7828.c > @@ -1,12 +1,12 @@ > /* > - * ads7828.c - lm_sensors driver for ads7828 12-bit 8-channel ADC > - * (C) 2007 EADS Astrium > + * ads7828.c - driver for TI ADS7828 8-channel A/D converter and compatibles > * > - * This driver is based on the lm75 and other lm_sensors/hwmon drivers > + * Copyright (C) 2007 EADS Astrium > + * Copyright (C) Steve Hardy > + * Copyright (C) 2012 Savoir-faire Linux Inc. > + * Guillaume Roguez > * > - * Written by Steve Hardy > - * > - * 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 +34,15 @@ > #include > > /* 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 */ > + > +/* List of supported devices */ > +enum ads7828_chips { ads7828, ads7830 }; > > /* Addresses to scan */ > static const unsigned short normal_i2c[] = { 0x48, 0x49, 0x4a, 0x4b, > @@ -57,23 +58,27 @@ module_param(vref_mv, int, S_IRUGO); > > /* Global Variables */ > 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. > + * @lsb_resol: Resolution of the A/D converter sample LSB. > + * @read_channel: Function used to read a channel. > + */ > 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]; > + unsigned int lsb_resol; > + s32 (*read_channel)(const struct i2c_client *client, u8 command); > }; > > -/* 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 */ > @@ -97,8 +102,7 @@ static struct ads7828_data *ads7828_update_device(struct device *dev) > > for (ch = 0; ch < ADS7828_NCH; ch++) { > u8 cmd = channel_cmd_byte(ch); > - data->adc_input[ch] = > - i2c_smbus_read_word_swapped(client, cmd); > + data->adc_input[ch] = data->read_channel(client, cmd); > } > data->last_updated = jiffies; > data->valid = 1; > @@ -116,8 +120,8 @@ static ssize_t show_in(struct device *dev, struct device_attribute *da, > struct sensor_device_attribute *attr = to_sensor_dev_attr(da); > struct ads7828_data *data = ads7828_update_device(dev); > /* Print value (in mV as specified in sysfs-interface documentation) */ > - return sprintf(buf, "%d\n", (data->adc_input[attr->index] * > - ads7828_lsb_resol)/1000); > + return sprintf(buf, "%d\n", > + (data->adc_input[attr->index] * data->lsb_resol) / 1000); > } > > #define in_reg(offset)\ > @@ -158,31 +162,13 @@ 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) > { > struct i2c_adapter *adapter = client->adapter; > int ch; > + bool is_8bit = false; > > /* Check we have a valid client */ > if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)) > @@ -193,20 +179,30 @@ static int ads7828_detect(struct i2c_client *client, > * dedicated register so attempt to sanity check using knowledge of > * the chip > * - Read from the 8 channel addresses > - * - Check the top 4 bits of each result are not set (12 data bits) > + * - Check the top 4 bits of each result: > + * - They should not be set in case of 12-bit samples > + * - The two bytes should be equal in case of 8-bit samples > */ > for (ch = 0; ch < ADS7828_NCH; ch++) { > u16 in_data; > u8 cmd = channel_cmd_byte(ch); > in_data = i2c_smbus_read_word_swapped(client, cmd); > if (in_data & 0xF000) { > - pr_debug("%s : Doesn't look like an ads7828 device\n", > - __func__); > - return -ENODEV; > + if ((in_data >> 8) == (in_data & 0xFF)) { > + /* Seems to be an ADS7830 (8-bit sample) */ > + is_8bit = true; > + } else { > + dev_dbg(&client->dev, "doesn't look like an " > + "ADS7828 compatible device\n"); > + return -ENODEV; > + } > } > } > > - strlcpy(info->type, "ads7828", I2C_NAME_SIZE); > + if (is_8bit) > + strlcpy(info->type, "ads7830", I2C_NAME_SIZE); > + else > + strlcpy(info->type, "ads7828", I2C_NAME_SIZE); > > return 0; > } > @@ -223,6 +219,15 @@ static int ads7828_probe(struct i2c_client *client, > goto exit; > } > > + /* ADS7828 uses 12-bit samples, while ADS7830 is 8-bit */ > + if (id->driver_data == ads7828) { > + data->read_channel = i2c_smbus_read_word_swapped; > + data->lsb_resol = (vref_mv * 1000) / 4096; > + } else { > + data->read_channel = i2c_smbus_read_byte_data; > + data->lsb_resol = (vref_mv * 1000) / 256; > + } > + > i2c_set_clientdata(client, data); > mutex_init(&data->update_lock); > > @@ -247,6 +252,25 @@ exit: > return err; > } > > +static const struct i2c_device_id ads7828_ids[] = { > + { "ads7828", ads7828 }, > + { "ads7830", ads7830 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, ads7828_ids); > + > +static struct i2c_driver ads7828_driver = { > + .class = I2C_CLASS_HWMON, > + .driver = { > + .name = "ads7828", > + }, > + .probe = ads7828_probe, > + .remove = ads7828_remove, > + .id_table = ads7828_ids, > + .detect = ads7828_detect, > + .address_list = normal_i2c, > +}; > + > static int __init sensors_ads7828_init(void) > { > /* Initialize the command byte according to module parameters */ > @@ -255,9 +279,6 @@ static int __init sensors_ads7828_init(void) > ads7828_cmd_byte |= int_vref ? > ADS7828_CMD_PD3 : ADS7828_CMD_PD1; > > - /* Calculate the LSB resolution */ > - ads7828_lsb_resol = (vref_mv*1000)/4096; > - > return i2c_add_driver(&ads7828_driver); > } > > @@ -267,7 +288,7 @@ static void __exit sensors_ads7828_exit(void) > } > > MODULE_AUTHOR("Steve Hardy "); > -MODULE_DESCRIPTION("ADS7828 driver"); > +MODULE_DESCRIPTION("Driver for TI ADS7828 A/D converter and compatibles"); > MODULE_LICENSE("GPL"); > > module_init(sensors_ads7828_init); > -- > 1.7.11.4 > > -- 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/