Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753053Ab0FBInE (ORCPT ); Wed, 2 Jun 2010 04:43:04 -0400 Received: from nwd2mail10.analog.com ([137.71.25.55]:11891 "EHLO nwd2mail10.analog.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751604Ab0FBInB (ORCPT ); Wed, 2 Jun 2010 04:43:01 -0400 X-IronPort-AV: E=Sophos;i="4.53,346,1272859200"; d="scan'208";a="16863287" Subject: [PATCH v2] regulator: new drivers for AD5398 and AD5821 From: sonic zhang To: Mark Brown , Liam Girdwood CC: Linux Kernel , uclinux-dist-devel Content-Type: text/plain Date: Wed, 2 Jun 2010 16:51:34 +0800 Message-ID: <1275468694.2545.1.camel@eight.analog.com> MIME-Version: 1.0 X-Mailer: Evolution 2.8.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8839 Lines: 345 The AD5398 and AD5821 are single 10-bit DAC with 120 mA output current sink capability. They feature an internal reference and operates from a single 2.7 V to 5.5 V supply. This driver supports both the AD5398 and the AD5821. It adapts into the voltage and current framework. Signed-off-by: Sonic Zhang --- drivers/regulator/Kconfig | 6 + drivers/regulator/Makefile | 1 + drivers/regulator/ad5398.c | 285 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 292 insertions(+), 0 deletions(-) create mode 100644 drivers/regulator/ad5398.c diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 04f2e08..2ade09c 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -201,5 +201,11 @@ config REGULATOR_88PM8607 help This driver supports 88PM8607 voltage regulator chips. +config REGULATOR_AD5398 + tristate "Ananlog Devices AD5398/AD5821 regulators" + depends on I2C + help + This driver supports AD5398 and AD5821 current regulator chips. + endif diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile index 4e7feec..c256668 100644 --- a/drivers/regulator/Makefile +++ b/drivers/regulator/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_REGULATOR_FIXED_VOLTAGE) += fixed.o obj-$(CONFIG_REGULATOR_VIRTUAL_CONSUMER) += virtual.o obj-$(CONFIG_REGULATOR_USERSPACE_CONSUMER) += userspace-consumer.o +obj-$(CONFIG_REGULATOR_AD5398) += ad5398.o obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o obj-$(CONFIG_REGULATOR_DUMMY) += dummy.o obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o diff --git a/drivers/regulator/ad5398.c b/drivers/regulator/ad5398.c new file mode 100644 index 0000000..4d6cb26 --- /dev/null +++ b/drivers/regulator/ad5398.c @@ -0,0 +1,285 @@ +/* + * ad5398.c -- Voltage and current regulation for AD5398 and AD5821 + * + * Copyright 2010 Analog Devices Inc. + * + * Enter bugs at http://blackfin.uclinux.org/ + * + * Licensed under the GPL-2 or later. + */ +#include +#include +#include +#include +#include +#include +#include + +#define AD5398_CURRENT_EN_MASK 0x8000 + +struct ad5398_chip_info { + struct i2c_client *client; + int min_uA; + int max_uA; + unsigned int current_level; + unsigned int current_mask; + unsigned int current_offset; + struct regulator_dev rdev; +}; + +static int ad5398_calc_current(struct ad5398_chip_info *chip, + unsigned selector) +{ + unsigned range_uA = chip->max_uA - chip->min_uA; + + return chip->min_uA + (selector * range_uA / chip->current_level); +} + +static int ad5398_read_reg(struct i2c_client *client, unsigned short *data) +{ + unsigned short val; + int ret; + + ret = i2c_master_recv(client, (char *)&val, 2); + if (ret < 0) { + dev_err(&client->dev, "I2C read error\n"); + return ret; + } + *data = swab16(val); + + return ret; +} + +static int ad5398_write_reg(struct i2c_client *client, const unsigned short data) +{ + unsigned short val; + int ret; + + val = swab16(data); + ret = i2c_master_send(client, (char *)&val, 2); + if (ret < 0) + dev_err(&client->dev, "I2C write error\n"); + + return ret; +} + +static int ad5398_get_current_limit(struct regulator_dev *rdev) +{ + struct ad5398_chip_info *chip = rdev_get_drvdata(rdev); + struct i2c_client *client = chip->client; + unsigned short data; + int ret; + + ret = ad5398_read_reg(client, &data); + if (ret < 0) + return ret; + + ret = (data & chip->current_mask) >> chip->current_offset; + + return ad5398_calc_current(chip, ret); +} + +static int ad5398_set_current_limit(struct regulator_dev *rdev, int min_uA, int max_uA) +{ + struct ad5398_chip_info *chip = rdev_get_drvdata(rdev); + struct i2c_client *client = chip->client; + unsigned range_uA = chip->max_uA - chip->min_uA; + unsigned selector; + unsigned short data; + int ret; + + if (min_uA > chip->max_uA || max_uA < chip->min_uA) + return -EINVAL; + if (min_uA < chip->min_uA) + min_uA = chip->min_uA; + + selector = ((min_uA - chip->min_uA) * chip->current_level + + range_uA - 1) / range_uA; + if (ad5398_calc_current(chip, selector) > max_uA) + return -EINVAL; + + dev_dbg(&client->dev, "changing current %dmA\n", + ad5398_calc_current(chip, selector) / 1000); + + /* read chip enable bit */ + ret = ad5398_read_reg(client, &data); + if (ret < 0) + return ret; + + /* prepare register data */ + selector = (selector << chip->current_offset) & chip->current_mask; + selector |= (data & AD5398_CURRENT_EN_MASK); + + /* write the new current value back as well as enable bit */ + ret = ad5398_write_reg(client, (unsigned short)selector); + + return ret; +} + +static int ad5398_is_enabled(struct regulator_dev *rdev) +{ + struct ad5398_chip_info *chip = rdev_get_drvdata(rdev); + struct i2c_client *client = chip->client; + unsigned short data; + int ret; + + ret = ad5398_read_reg(client, &data); + if (ret < 0) + return ret; + + if (data & AD5398_CURRENT_EN_MASK) + return 1; + else + return 0; +} + +static int ad5398_enable(struct regulator_dev *rdev) +{ + struct ad5398_chip_info *chip = rdev_get_drvdata(rdev); + struct i2c_client *client = chip->client; + unsigned short data; + int ret; + + ret = ad5398_read_reg(client, &data); + if (ret < 0) + return ret; + + if (data & AD5398_CURRENT_EN_MASK) + return 0; + + data |= AD5398_CURRENT_EN_MASK; + + ret = ad5398_write_reg(client, data); + + return ret; +} + +static int ad5398_disable(struct regulator_dev *rdev) +{ + struct ad5398_chip_info *chip = rdev_get_drvdata(rdev); + struct i2c_client *client = chip->client; + unsigned short data; + int ret; + + ret = ad5398_read_reg(client, &data); + if (ret < 0) + return ret; + + if (!(data & AD5398_CURRENT_EN_MASK)) + return 0; + + data &= ~AD5398_CURRENT_EN_MASK; + + ret = ad5398_write_reg(client, data); + + return ret; +} + +static struct regulator_ops ad5398_ops = { + .get_current_limit = ad5398_get_current_limit, + .set_current_limit = ad5398_set_current_limit, + .enable = ad5398_enable, + .disable = ad5398_disable, + .is_enabled = ad5398_is_enabled, +}; + +static struct regulator_desc ad5398_reg = { + .name = "isink", + .id = 0, + .ops = &ad5398_ops, + .type = REGULATOR_CURRENT, + .owner = THIS_MODULE, +}; + +struct ad5398_current_data_format { + int current_bits; + int current_offset; +}; + +static const struct ad5398_current_data_format ad5398_df = {10, 4}; +static const struct ad5398_current_data_format ad5821_df = {10, 4}; + +static const struct i2c_device_id ad5398_id[] = { + { "ad5398", (kernel_ulong_t)&ad5398_df }, + { "ad5821", (kernel_ulong_t)&ad5821_df }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ad5398_id); + +static int ad5398_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct regulator_dev *rdev; + struct regulator_init_data *init_data = client->dev.platform_data; + struct ad5398_chip_info *chip; + struct ad5398_current_data_format *df = + (struct ad5398_current_data_format *)id->driver_data; + int ret; + + if (!init_data) + return -EINVAL; + + chip = kzalloc(sizeof(struct ad5398_chip_info), GFP_KERNEL); + if (!chip) + return -ENOMEM; + + chip->client = client; + + chip->min_uA = init_data->constraints.min_uA; + chip->max_uA = init_data->constraints.max_uA; + chip->current_level = 1 << df->current_bits; + chip->current_offset = df->current_offset; + chip->current_mask = (chip->current_level - 1) << chip->current_offset; + + rdev = regulator_register(&ad5398_reg, &client->dev, init_data, chip); + if (IS_ERR(rdev)) { + ret = PTR_ERR(rdev); + dev_err(&client->dev, "failed to register %s %s\n", + id->name, ad5398_reg.name); + goto err; + } + + i2c_set_clientdata(client, chip); + dev_dbg(&client->dev, "%s regulator driver loaded\n", id->name); + return 0; + +err: + kfree(chip); + return ret; +} + +static int ad5398_remove(struct i2c_client *client) +{ + struct ad5398_chip_info *chip = i2c_get_clientdata(client); + + regulator_unregister(&chip->rdev); + kfree(chip); + i2c_set_clientdata(client, NULL); + + return 0; +} + +static struct i2c_driver ad5398_driver = { + .probe = ad5398_probe, + .remove = ad5398_remove, + .driver = { + .name = "ad5398", + }, + .id_table = ad5398_id, +}; + +static int __init ad5398_init(void) +{ + return i2c_add_driver(&ad5398_driver); +} +module_init(ad5398_init); + +static void __exit ad5398_exit(void) +{ + i2c_del_driver(&ad5398_driver); +} +module_exit(ad5398_exit); + +MODULE_DESCRIPTION("AD5398 and AD5821 current regulator driver"); +MODULE_AUTHOR("Sonic Zhang"); +MODULE_LICENSE("GPL"); -- 1.6.0 -- 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/