530 lines
13 KiB
C
530 lines
13 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* max8660.c -- Voltage regulation for the Maxim 8660/8661
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*
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* based on max1586.c and wm8400-regulator.c
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*
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* Copyright (C) 2009 Wolfram Sang, Pengutronix e.K.
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*
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* Some info:
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*
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* Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX8660-MAX8661.pdf
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*
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* This chip is a bit nasty because it is a write-only device. Thus, the driver
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* uses shadow registers to keep track of its values. The main problem appears
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* to be the initialization: When Linux boots up, we cannot know if the chip is
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* in the default state or not, so we would have to pass such information in
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* platform_data. As this adds a bit of complexity to the driver, this is left
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* out for now until it is really needed.
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*
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* [A|S|M]DTV1 registers are currently not used, but [A|S|M]DTV2.
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*
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* If the driver is feature complete, it might be worth to check if one set of
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* functions for V3-V7 is sufficient. For maximum flexibility during
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* development, they are separated for now.
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*/
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#include <linux/module.h>
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#include <linux/err.h>
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#include <linux/i2c.h>
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#include <linux/platform_device.h>
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#include <linux/regulator/driver.h>
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#include <linux/slab.h>
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#include <linux/regulator/max8660.h>
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#include <linux/of.h>
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#include <linux/of_device.h>
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#include <linux/regulator/of_regulator.h>
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#define MAX8660_DCDC_MIN_UV 725000
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#define MAX8660_DCDC_MAX_UV 1800000
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#define MAX8660_DCDC_STEP 25000
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#define MAX8660_DCDC_MAX_SEL 0x2b
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#define MAX8660_LDO5_MIN_UV 1700000
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#define MAX8660_LDO5_MAX_UV 2000000
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#define MAX8660_LDO5_STEP 25000
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#define MAX8660_LDO5_MAX_SEL 0x0c
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#define MAX8660_LDO67_MIN_UV 1800000
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#define MAX8660_LDO67_MAX_UV 3300000
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#define MAX8660_LDO67_STEP 100000
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#define MAX8660_LDO67_MAX_SEL 0x0f
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enum {
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MAX8660_OVER1,
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MAX8660_OVER2,
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MAX8660_VCC1,
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MAX8660_ADTV1,
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MAX8660_ADTV2,
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MAX8660_SDTV1,
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MAX8660_SDTV2,
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MAX8660_MDTV1,
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MAX8660_MDTV2,
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MAX8660_L12VCR,
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MAX8660_FPWM,
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MAX8660_N_REGS, /* not a real register */
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};
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struct max8660 {
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struct i2c_client *client;
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u8 shadow_regs[MAX8660_N_REGS]; /* as chip is write only */
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};
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static int max8660_write(struct max8660 *max8660, u8 reg, u8 mask, u8 val)
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{
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static const u8 max8660_addresses[MAX8660_N_REGS] = {
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0x10, 0x12, 0x20, 0x23, 0x24, 0x29, 0x2a, 0x32, 0x33, 0x39, 0x80
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};
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int ret;
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u8 reg_val = (max8660->shadow_regs[reg] & mask) | val;
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dev_vdbg(&max8660->client->dev, "Writing reg %02x with %02x\n",
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max8660_addresses[reg], reg_val);
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ret = i2c_smbus_write_byte_data(max8660->client,
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max8660_addresses[reg], reg_val);
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if (ret == 0)
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max8660->shadow_regs[reg] = reg_val;
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return ret;
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}
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/*
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* DCDC functions
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*/
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static int max8660_dcdc_is_enabled(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 val = max8660->shadow_regs[MAX8660_OVER1];
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u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;
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return !!(val & mask);
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}
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static int max8660_dcdc_enable(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 bit = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;
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return max8660_write(max8660, MAX8660_OVER1, 0xff, bit);
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}
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static int max8660_dcdc_disable(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? ~1 : ~4;
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return max8660_write(max8660, MAX8660_OVER1, mask, 0);
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}
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static int max8660_dcdc_get_voltage_sel(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
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u8 selector = max8660->shadow_regs[reg];
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return selector;
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}
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static int max8660_dcdc_set_voltage_sel(struct regulator_dev *rdev,
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unsigned int selector)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 reg, bits;
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int ret;
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reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
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ret = max8660_write(max8660, reg, 0, selector);
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if (ret)
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return ret;
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/* Select target voltage register and activate regulation */
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bits = (rdev_get_id(rdev) == MAX8660_V3) ? 0x03 : 0x30;
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return max8660_write(max8660, MAX8660_VCC1, 0xff, bits);
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}
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static struct regulator_ops max8660_dcdc_ops = {
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.is_enabled = max8660_dcdc_is_enabled,
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.list_voltage = regulator_list_voltage_linear,
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.map_voltage = regulator_map_voltage_linear,
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.set_voltage_sel = max8660_dcdc_set_voltage_sel,
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.get_voltage_sel = max8660_dcdc_get_voltage_sel,
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};
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/*
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* LDO5 functions
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*/
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static int max8660_ldo5_get_voltage_sel(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 selector = max8660->shadow_regs[MAX8660_MDTV2];
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return selector;
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}
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static int max8660_ldo5_set_voltage_sel(struct regulator_dev *rdev,
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unsigned int selector)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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int ret;
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ret = max8660_write(max8660, MAX8660_MDTV2, 0, selector);
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if (ret)
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return ret;
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/* Select target voltage register and activate regulation */
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return max8660_write(max8660, MAX8660_VCC1, 0xff, 0xc0);
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}
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static const struct regulator_ops max8660_ldo5_ops = {
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.list_voltage = regulator_list_voltage_linear,
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.map_voltage = regulator_map_voltage_linear,
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.set_voltage_sel = max8660_ldo5_set_voltage_sel,
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.get_voltage_sel = max8660_ldo5_get_voltage_sel,
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};
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/*
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* LDO67 functions
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*/
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static int max8660_ldo67_is_enabled(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 val = max8660->shadow_regs[MAX8660_OVER2];
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u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;
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return !!(val & mask);
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}
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static int max8660_ldo67_enable(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 bit = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;
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return max8660_write(max8660, MAX8660_OVER2, 0xff, bit);
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}
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static int max8660_ldo67_disable(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? ~2 : ~4;
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return max8660_write(max8660, MAX8660_OVER2, mask, 0);
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}
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static int max8660_ldo67_get_voltage_sel(struct regulator_dev *rdev)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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u8 shift = (rdev_get_id(rdev) == MAX8660_V6) ? 0 : 4;
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u8 selector = (max8660->shadow_regs[MAX8660_L12VCR] >> shift) & 0xf;
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return selector;
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}
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static int max8660_ldo67_set_voltage_sel(struct regulator_dev *rdev,
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unsigned int selector)
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{
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struct max8660 *max8660 = rdev_get_drvdata(rdev);
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if (rdev_get_id(rdev) == MAX8660_V6)
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return max8660_write(max8660, MAX8660_L12VCR, 0xf0, selector);
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else
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return max8660_write(max8660, MAX8660_L12VCR, 0x0f,
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selector << 4);
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}
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static const struct regulator_ops max8660_ldo67_ops = {
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.is_enabled = max8660_ldo67_is_enabled,
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.enable = max8660_ldo67_enable,
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.disable = max8660_ldo67_disable,
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.list_voltage = regulator_list_voltage_linear,
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.map_voltage = regulator_map_voltage_linear,
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.get_voltage_sel = max8660_ldo67_get_voltage_sel,
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.set_voltage_sel = max8660_ldo67_set_voltage_sel,
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};
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static const struct regulator_desc max8660_reg[] = {
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{
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.name = "V3(DCDC)",
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.id = MAX8660_V3,
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.ops = &max8660_dcdc_ops,
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.type = REGULATOR_VOLTAGE,
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.n_voltages = MAX8660_DCDC_MAX_SEL + 1,
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.owner = THIS_MODULE,
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.min_uV = MAX8660_DCDC_MIN_UV,
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.uV_step = MAX8660_DCDC_STEP,
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},
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{
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.name = "V4(DCDC)",
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.id = MAX8660_V4,
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.ops = &max8660_dcdc_ops,
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.type = REGULATOR_VOLTAGE,
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.n_voltages = MAX8660_DCDC_MAX_SEL + 1,
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.owner = THIS_MODULE,
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.min_uV = MAX8660_DCDC_MIN_UV,
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.uV_step = MAX8660_DCDC_STEP,
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},
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{
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.name = "V5(LDO)",
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.id = MAX8660_V5,
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.ops = &max8660_ldo5_ops,
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.type = REGULATOR_VOLTAGE,
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.n_voltages = MAX8660_LDO5_MAX_SEL + 1,
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.owner = THIS_MODULE,
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.min_uV = MAX8660_LDO5_MIN_UV,
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.uV_step = MAX8660_LDO5_STEP,
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},
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{
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.name = "V6(LDO)",
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.id = MAX8660_V6,
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.ops = &max8660_ldo67_ops,
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.type = REGULATOR_VOLTAGE,
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.n_voltages = MAX8660_LDO67_MAX_SEL + 1,
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.owner = THIS_MODULE,
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.min_uV = MAX8660_LDO67_MIN_UV,
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.uV_step = MAX8660_LDO67_STEP,
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},
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{
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.name = "V7(LDO)",
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.id = MAX8660_V7,
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.ops = &max8660_ldo67_ops,
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.type = REGULATOR_VOLTAGE,
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.n_voltages = MAX8660_LDO67_MAX_SEL + 1,
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.owner = THIS_MODULE,
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.min_uV = MAX8660_LDO67_MIN_UV,
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.uV_step = MAX8660_LDO67_STEP,
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},
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};
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enum {
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MAX8660 = 0,
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MAX8661 = 1,
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};
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#ifdef CONFIG_OF
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static const struct of_device_id max8660_dt_ids[] = {
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{ .compatible = "maxim,max8660", .data = (void *) MAX8660 },
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{ .compatible = "maxim,max8661", .data = (void *) MAX8661 },
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{ }
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};
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MODULE_DEVICE_TABLE(of, max8660_dt_ids);
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static int max8660_pdata_from_dt(struct device *dev,
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struct device_node **of_node,
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struct max8660_platform_data *pdata)
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{
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int matched, i;
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struct device_node *np;
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struct max8660_subdev_data *sub;
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struct of_regulator_match rmatch[ARRAY_SIZE(max8660_reg)] = { };
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np = of_get_child_by_name(dev->of_node, "regulators");
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if (!np) {
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dev_err(dev, "missing 'regulators' subnode in DT\n");
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return -EINVAL;
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}
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for (i = 0; i < ARRAY_SIZE(rmatch); i++)
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rmatch[i].name = max8660_reg[i].name;
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matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(rmatch));
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of_node_put(np);
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if (matched <= 0)
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return matched;
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pdata->subdevs = devm_kcalloc(dev,
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matched,
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sizeof(struct max8660_subdev_data),
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GFP_KERNEL);
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if (!pdata->subdevs)
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return -ENOMEM;
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pdata->num_subdevs = matched;
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sub = pdata->subdevs;
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for (i = 0; i < matched; i++) {
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sub->id = i;
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sub->name = rmatch[i].name;
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sub->platform_data = rmatch[i].init_data;
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of_node[i] = rmatch[i].of_node;
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sub++;
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}
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return 0;
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}
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#else
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static inline int max8660_pdata_from_dt(struct device *dev,
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struct device_node **of_node,
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struct max8660_platform_data *pdata)
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{
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return 0;
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}
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#endif
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static int max8660_probe(struct i2c_client *client,
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const struct i2c_device_id *i2c_id)
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{
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struct device *dev = &client->dev;
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struct max8660_platform_data pdata_of, *pdata = dev_get_platdata(dev);
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struct regulator_config config = { };
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struct max8660 *max8660;
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int boot_on, i, id, ret = -EINVAL;
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struct device_node *of_node[MAX8660_V_END];
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unsigned long type;
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if (dev->of_node && !pdata) {
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const struct of_device_id *id;
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id = of_match_device(of_match_ptr(max8660_dt_ids), dev);
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if (!id)
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return -ENODEV;
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ret = max8660_pdata_from_dt(dev, of_node, &pdata_of);
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if (ret < 0)
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return ret;
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pdata = &pdata_of;
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type = (unsigned long) id->data;
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} else {
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type = i2c_id->driver_data;
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memset(of_node, 0, sizeof(of_node));
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}
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if (pdata->num_subdevs > MAX8660_V_END) {
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dev_err(dev, "Too many regulators found!\n");
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return -EINVAL;
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}
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max8660 = devm_kzalloc(dev, sizeof(struct max8660), GFP_KERNEL);
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if (!max8660)
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return -ENOMEM;
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max8660->client = client;
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if (pdata->en34_is_high) {
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/* Simulate always on */
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max8660->shadow_regs[MAX8660_OVER1] = 5;
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} else {
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/* Otherwise devices can be toggled via software */
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max8660_dcdc_ops.enable = max8660_dcdc_enable;
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max8660_dcdc_ops.disable = max8660_dcdc_disable;
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}
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/*
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* First, set up shadow registers to prevent glitches. As some
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* registers are shared between regulators, everything must be properly
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* set up for all regulators in advance.
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*/
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max8660->shadow_regs[MAX8660_ADTV1] =
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max8660->shadow_regs[MAX8660_ADTV2] =
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max8660->shadow_regs[MAX8660_SDTV1] =
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max8660->shadow_regs[MAX8660_SDTV2] = 0x1b;
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max8660->shadow_regs[MAX8660_MDTV1] =
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max8660->shadow_regs[MAX8660_MDTV2] = 0x04;
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for (i = 0; i < pdata->num_subdevs; i++) {
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if (!pdata->subdevs[i].platform_data)
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boot_on = false;
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else
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boot_on = pdata->subdevs[i].platform_data->constraints.boot_on;
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switch (pdata->subdevs[i].id) {
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case MAX8660_V3:
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if (boot_on)
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max8660->shadow_regs[MAX8660_OVER1] |= 1;
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break;
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case MAX8660_V4:
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if (boot_on)
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max8660->shadow_regs[MAX8660_OVER1] |= 4;
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break;
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case MAX8660_V5:
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break;
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case MAX8660_V6:
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if (boot_on)
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max8660->shadow_regs[MAX8660_OVER2] |= 2;
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break;
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case MAX8660_V7:
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if (type == MAX8661) {
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dev_err(dev, "Regulator not on this chip!\n");
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return -EINVAL;
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}
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if (boot_on)
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max8660->shadow_regs[MAX8660_OVER2] |= 4;
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break;
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default:
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dev_err(dev, "invalid regulator %s\n",
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pdata->subdevs[i].name);
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return ret;
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}
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}
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/* Finally register devices */
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for (i = 0; i < pdata->num_subdevs; i++) {
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struct regulator_dev *rdev;
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|
|
|
id = pdata->subdevs[i].id;
|
|
|
|
config.dev = dev;
|
|
config.init_data = pdata->subdevs[i].platform_data;
|
|
config.of_node = of_node[i];
|
|
config.driver_data = max8660;
|
|
|
|
rdev = devm_regulator_register(&client->dev,
|
|
&max8660_reg[id], &config);
|
|
if (IS_ERR(rdev)) {
|
|
ret = PTR_ERR(rdev);
|
|
dev_err(&client->dev, "failed to register %s\n",
|
|
max8660_reg[id].name);
|
|
return PTR_ERR(rdev);
|
|
}
|
|
}
|
|
|
|
i2c_set_clientdata(client, max8660);
|
|
return 0;
|
|
}
|
|
|
|
static const struct i2c_device_id max8660_id[] = {
|
|
{ .name = "max8660", .driver_data = MAX8660 },
|
|
{ .name = "max8661", .driver_data = MAX8661 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, max8660_id);
|
|
|
|
static struct i2c_driver max8660_driver = {
|
|
.probe = max8660_probe,
|
|
.driver = {
|
|
.name = "max8660",
|
|
},
|
|
.id_table = max8660_id,
|
|
};
|
|
|
|
static int __init max8660_init(void)
|
|
{
|
|
return i2c_add_driver(&max8660_driver);
|
|
}
|
|
subsys_initcall(max8660_init);
|
|
|
|
static void __exit max8660_exit(void)
|
|
{
|
|
i2c_del_driver(&max8660_driver);
|
|
}
|
|
module_exit(max8660_exit);
|
|
|
|
/* Module information */
|
|
MODULE_DESCRIPTION("MAXIM 8660/8661 voltage regulator driver");
|
|
MODULE_AUTHOR("Wolfram Sang");
|
|
MODULE_LICENSE("GPL v2");
|