linux/drivers/regulator/wm8994-regulator.c
Jonathan Bakker cfd24b14eb regulator: wm8994: Add an off-on delay for WM8994 variant
[ Upstream commit 92d96b6037 ]

As per Table 130 of the wm8994 datasheet at [1], there is an off-on
delay for LDO1 and LDO2.  In the wm8958 datasheet [2], I could not
find any reference to it.  I could not find a wm1811 datasheet to
double-check there, but as no one has complained presumably it works
without it.

This solves the issue on Samsung Aries boards with a wm8994 where
register writes fail when the device is powered off and back-on
quickly.

[1] https://statics.cirrus.com/pubs/proDatasheet/WM8994_Rev4.6.pdf
[2] https://statics.cirrus.com/pubs/proDatasheet/WM8958_v3.5.pdf

Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/CY4PR04MB056771CFB80DC447C30D5A31CB1D9@CY4PR04MB0567.namprd04.prod.outlook.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:34:16 +02:00

240 lines
5.8 KiB
C

// SPDX-License-Identifier: GPL-2.0+
//
// wm8994-regulator.c -- Regulator driver for the WM8994
//
// Copyright 2009 Wolfson Microelectronics PLC.
//
// Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/gpio/consumer.h>
#include <linux/slab.h>
#include <linux/mfd/wm8994/core.h>
#include <linux/mfd/wm8994/registers.h>
#include <linux/mfd/wm8994/pdata.h>
struct wm8994_ldo {
struct regulator_dev *regulator;
struct wm8994 *wm8994;
struct regulator_consumer_supply supply;
struct regulator_init_data init_data;
};
#define WM8994_LDO1_MAX_SELECTOR 0x7
#define WM8994_LDO2_MAX_SELECTOR 0x3
static const struct regulator_ops wm8994_ldo1_ops = {
.list_voltage = regulator_list_voltage_linear,
.map_voltage = regulator_map_voltage_linear,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
};
static int wm8994_ldo2_list_voltage(struct regulator_dev *rdev,
unsigned int selector)
{
struct wm8994_ldo *ldo = rdev_get_drvdata(rdev);
if (selector > WM8994_LDO2_MAX_SELECTOR)
return -EINVAL;
switch (ldo->wm8994->type) {
case WM8994:
return (selector * 100000) + 900000;
case WM8958:
return (selector * 100000) + 1000000;
case WM1811:
switch (selector) {
case 0:
return -EINVAL;
default:
return (selector * 100000) + 950000;
}
break;
default:
return -EINVAL;
}
}
static const struct regulator_ops wm8994_ldo2_ops = {
.list_voltage = wm8994_ldo2_list_voltage,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
};
static const struct regulator_desc wm8994_ldo_desc[] = {
{
.name = "LDO1",
.id = 1,
.type = REGULATOR_VOLTAGE,
.n_voltages = WM8994_LDO1_MAX_SELECTOR + 1,
.vsel_reg = WM8994_LDO_1,
.vsel_mask = WM8994_LDO1_VSEL_MASK,
.ops = &wm8994_ldo1_ops,
.min_uV = 2400000,
.uV_step = 100000,
.enable_time = 3000,
.off_on_delay = 36000,
.owner = THIS_MODULE,
},
{
.name = "LDO2",
.id = 2,
.type = REGULATOR_VOLTAGE,
.n_voltages = WM8994_LDO2_MAX_SELECTOR + 1,
.vsel_reg = WM8994_LDO_2,
.vsel_mask = WM8994_LDO2_VSEL_MASK,
.ops = &wm8994_ldo2_ops,
.enable_time = 3000,
.off_on_delay = 36000,
.owner = THIS_MODULE,
},
};
static const struct regulator_desc wm8958_ldo_desc[] = {
{
.name = "LDO1",
.id = 1,
.type = REGULATOR_VOLTAGE,
.n_voltages = WM8994_LDO1_MAX_SELECTOR + 1,
.vsel_reg = WM8994_LDO_1,
.vsel_mask = WM8994_LDO1_VSEL_MASK,
.ops = &wm8994_ldo1_ops,
.min_uV = 2400000,
.uV_step = 100000,
.enable_time = 3000,
.owner = THIS_MODULE,
},
{
.name = "LDO2",
.id = 2,
.type = REGULATOR_VOLTAGE,
.n_voltages = WM8994_LDO2_MAX_SELECTOR + 1,
.vsel_reg = WM8994_LDO_2,
.vsel_mask = WM8994_LDO2_VSEL_MASK,
.ops = &wm8994_ldo2_ops,
.enable_time = 3000,
.owner = THIS_MODULE,
},
};
static const struct regulator_consumer_supply wm8994_ldo_consumer[] = {
{ .supply = "AVDD1" },
{ .supply = "DCVDD" },
};
static const struct regulator_init_data wm8994_ldo_default[] = {
{
.constraints = {
.valid_ops_mask = REGULATOR_CHANGE_STATUS,
},
.num_consumer_supplies = 1,
},
{
.constraints = {
.valid_ops_mask = REGULATOR_CHANGE_STATUS,
},
.num_consumer_supplies = 1,
},
};
static int wm8994_ldo_probe(struct platform_device *pdev)
{
struct wm8994 *wm8994 = dev_get_drvdata(pdev->dev.parent);
struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
int id = pdev->id % ARRAY_SIZE(pdata->ldo);
struct regulator_config config = { };
struct wm8994_ldo *ldo;
struct gpio_desc *gpiod;
int ret;
dev_dbg(&pdev->dev, "Probing LDO%d\n", id + 1);
ldo = devm_kzalloc(&pdev->dev, sizeof(struct wm8994_ldo), GFP_KERNEL);
if (!ldo)
return -ENOMEM;
ldo->wm8994 = wm8994;
ldo->supply = wm8994_ldo_consumer[id];
ldo->supply.dev_name = dev_name(wm8994->dev);
config.dev = wm8994->dev;
config.driver_data = ldo;
config.regmap = wm8994->regmap;
config.init_data = &ldo->init_data;
/*
* Look up LDO enable GPIO from the parent device node, we don't
* use devm because the regulator core will free the GPIO
*/
gpiod = gpiod_get_optional(pdev->dev.parent,
id ? "wlf,ldo2ena" : "wlf,ldo1ena",
GPIOD_OUT_LOW |
GPIOD_FLAGS_BIT_NONEXCLUSIVE);
if (IS_ERR(gpiod))
return PTR_ERR(gpiod);
config.ena_gpiod = gpiod;
/* Use default constraints if none set up */
if (!pdata || !pdata->ldo[id].init_data || wm8994->dev->of_node) {
dev_dbg(wm8994->dev, "Using default init data, supply %s %s\n",
ldo->supply.dev_name, ldo->supply.supply);
ldo->init_data = wm8994_ldo_default[id];
ldo->init_data.consumer_supplies = &ldo->supply;
if (!gpiod)
ldo->init_data.constraints.valid_ops_mask = 0;
} else {
ldo->init_data = *pdata->ldo[id].init_data;
}
/*
* At this point the GPIO descriptor is handled over to the
* regulator core and we need not worry about it on the
* error path.
*/
if (ldo->wm8994->type == WM8994) {
ldo->regulator = devm_regulator_register(&pdev->dev,
&wm8994_ldo_desc[id],
&config);
} else {
ldo->regulator = devm_regulator_register(&pdev->dev,
&wm8958_ldo_desc[id],
&config);
}
if (IS_ERR(ldo->regulator)) {
ret = PTR_ERR(ldo->regulator);
dev_err(wm8994->dev, "Failed to register LDO%d: %d\n",
id + 1, ret);
return ret;
}
platform_set_drvdata(pdev, ldo);
return 0;
}
static struct platform_driver wm8994_ldo_driver = {
.probe = wm8994_ldo_probe,
.driver = {
.name = "wm8994-ldo",
},
};
module_platform_driver(wm8994_ldo_driver);
/* Module information */
MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("WM8994 LDO driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:wm8994-ldo");