linux/drivers/mfd/stmfx.c
Uwe Kleine-König c788f6e6aa mfd: stmfx: Improve error message triggered by regulator fault in .remove()
Returning a non-zero value in an i2c remove callback results in the i2c
core emitting a very generic error message ("remove failed (-ESOMETHING),
will be ignored") and as the message indicates not further error handling
is done.

Instead emit a more specific error message and then return zero in
.remove().

The long-term goal is to make the i2c remove prototype return void, making
all implementations return 0 is preparatory work for this change.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220214150710.312269-1-u.kleine-koenig@pengutronix.de
2022-03-08 09:44:05 +00:00

569 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Driver for STMicroelectronics Multi-Function eXpander (STMFX) core
*
* Copyright (C) 2019 STMicroelectronics
* Author(s): Amelie Delaunay <amelie.delaunay@st.com>.
*/
#include <linux/bitfield.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/mfd/core.h>
#include <linux/mfd/stmfx.h>
#include <linux/module.h>
#include <linux/regulator/consumer.h>
static bool stmfx_reg_volatile(struct device *dev, unsigned int reg)
{
switch (reg) {
case STMFX_REG_SYS_CTRL:
case STMFX_REG_IRQ_SRC_EN:
case STMFX_REG_IRQ_PENDING:
case STMFX_REG_IRQ_GPI_PENDING1:
case STMFX_REG_IRQ_GPI_PENDING2:
case STMFX_REG_IRQ_GPI_PENDING3:
case STMFX_REG_GPIO_STATE1:
case STMFX_REG_GPIO_STATE2:
case STMFX_REG_GPIO_STATE3:
case STMFX_REG_IRQ_GPI_SRC1:
case STMFX_REG_IRQ_GPI_SRC2:
case STMFX_REG_IRQ_GPI_SRC3:
case STMFX_REG_GPO_SET1:
case STMFX_REG_GPO_SET2:
case STMFX_REG_GPO_SET3:
case STMFX_REG_GPO_CLR1:
case STMFX_REG_GPO_CLR2:
case STMFX_REG_GPO_CLR3:
return true;
default:
return false;
}
}
static bool stmfx_reg_writeable(struct device *dev, unsigned int reg)
{
return (reg >= STMFX_REG_SYS_CTRL);
}
static const struct regmap_config stmfx_regmap_config = {
.reg_bits = 8,
.reg_stride = 1,
.val_bits = 8,
.max_register = STMFX_REG_MAX,
.volatile_reg = stmfx_reg_volatile,
.writeable_reg = stmfx_reg_writeable,
.cache_type = REGCACHE_RBTREE,
};
static const struct resource stmfx_pinctrl_resources[] = {
DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_GPIO),
};
static const struct resource stmfx_idd_resources[] = {
DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_IDD),
DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_ERROR),
};
static const struct resource stmfx_ts_resources[] = {
DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_DET),
DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_NE),
DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_TH),
DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_FULL),
DEFINE_RES_IRQ(STMFX_REG_IRQ_SRC_EN_TS_OVF),
};
static struct mfd_cell stmfx_cells[] = {
{
.of_compatible = "st,stmfx-0300-pinctrl",
.name = "stmfx-pinctrl",
.resources = stmfx_pinctrl_resources,
.num_resources = ARRAY_SIZE(stmfx_pinctrl_resources),
},
{
.of_compatible = "st,stmfx-0300-idd",
.name = "stmfx-idd",
.resources = stmfx_idd_resources,
.num_resources = ARRAY_SIZE(stmfx_idd_resources),
},
{
.of_compatible = "st,stmfx-0300-ts",
.name = "stmfx-ts",
.resources = stmfx_ts_resources,
.num_resources = ARRAY_SIZE(stmfx_ts_resources),
},
};
static u8 stmfx_func_to_mask(u32 func)
{
u8 mask = 0;
if (func & STMFX_FUNC_GPIO)
mask |= STMFX_REG_SYS_CTRL_GPIO_EN;
if ((func & STMFX_FUNC_ALTGPIO_LOW) || (func & STMFX_FUNC_ALTGPIO_HIGH))
mask |= STMFX_REG_SYS_CTRL_ALTGPIO_EN;
if (func & STMFX_FUNC_TS)
mask |= STMFX_REG_SYS_CTRL_TS_EN;
if (func & STMFX_FUNC_IDD)
mask |= STMFX_REG_SYS_CTRL_IDD_EN;
return mask;
}
int stmfx_function_enable(struct stmfx *stmfx, u32 func)
{
u32 sys_ctrl;
u8 mask;
int ret;
ret = regmap_read(stmfx->map, STMFX_REG_SYS_CTRL, &sys_ctrl);
if (ret)
return ret;
/*
* IDD and TS have priority in STMFX FW, so if IDD and TS are enabled,
* ALTGPIO function is disabled by STMFX FW. If IDD or TS is enabled,
* the number of aGPIO available decreases. To avoid GPIO management
* disturbance, abort IDD or TS function enable in this case.
*/
if (((func & STMFX_FUNC_IDD) || (func & STMFX_FUNC_TS)) &&
(sys_ctrl & STMFX_REG_SYS_CTRL_ALTGPIO_EN)) {
dev_err(stmfx->dev, "ALTGPIO function already enabled\n");
return -EBUSY;
}
/* If TS is enabled, aGPIO[3:0] cannot be used */
if ((func & STMFX_FUNC_ALTGPIO_LOW) &&
(sys_ctrl & STMFX_REG_SYS_CTRL_TS_EN)) {
dev_err(stmfx->dev, "TS in use, aGPIO[3:0] unavailable\n");
return -EBUSY;
}
/* If IDD is enabled, aGPIO[7:4] cannot be used */
if ((func & STMFX_FUNC_ALTGPIO_HIGH) &&
(sys_ctrl & STMFX_REG_SYS_CTRL_IDD_EN)) {
dev_err(stmfx->dev, "IDD in use, aGPIO[7:4] unavailable\n");
return -EBUSY;
}
mask = stmfx_func_to_mask(func);
return regmap_update_bits(stmfx->map, STMFX_REG_SYS_CTRL, mask, mask);
}
EXPORT_SYMBOL_GPL(stmfx_function_enable);
int stmfx_function_disable(struct stmfx *stmfx, u32 func)
{
u8 mask = stmfx_func_to_mask(func);
return regmap_update_bits(stmfx->map, STMFX_REG_SYS_CTRL, mask, 0);
}
EXPORT_SYMBOL_GPL(stmfx_function_disable);
static void stmfx_irq_bus_lock(struct irq_data *data)
{
struct stmfx *stmfx = irq_data_get_irq_chip_data(data);
mutex_lock(&stmfx->lock);
}
static void stmfx_irq_bus_sync_unlock(struct irq_data *data)
{
struct stmfx *stmfx = irq_data_get_irq_chip_data(data);
regmap_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, stmfx->irq_src);
mutex_unlock(&stmfx->lock);
}
static void stmfx_irq_mask(struct irq_data *data)
{
struct stmfx *stmfx = irq_data_get_irq_chip_data(data);
stmfx->irq_src &= ~BIT(data->hwirq % 8);
}
static void stmfx_irq_unmask(struct irq_data *data)
{
struct stmfx *stmfx = irq_data_get_irq_chip_data(data);
stmfx->irq_src |= BIT(data->hwirq % 8);
}
static struct irq_chip stmfx_irq_chip = {
.name = "stmfx-core",
.irq_bus_lock = stmfx_irq_bus_lock,
.irq_bus_sync_unlock = stmfx_irq_bus_sync_unlock,
.irq_mask = stmfx_irq_mask,
.irq_unmask = stmfx_irq_unmask,
};
static irqreturn_t stmfx_irq_handler(int irq, void *data)
{
struct stmfx *stmfx = data;
unsigned long bits;
u32 pending, ack;
int n, ret;
ret = regmap_read(stmfx->map, STMFX_REG_IRQ_PENDING, &pending);
if (ret)
return IRQ_NONE;
/*
* There is no ACK for GPIO, MFX_REG_IRQ_PENDING_GPIO is a logical OR
* of MFX_REG_IRQ_GPI _PENDING1/_PENDING2/_PENDING3
*/
ack = pending & ~BIT(STMFX_REG_IRQ_SRC_EN_GPIO);
if (ack) {
ret = regmap_write(stmfx->map, STMFX_REG_IRQ_ACK, ack);
if (ret)
return IRQ_NONE;
}
bits = pending;
for_each_set_bit(n, &bits, STMFX_REG_IRQ_SRC_MAX)
handle_nested_irq(irq_find_mapping(stmfx->irq_domain, n));
return IRQ_HANDLED;
}
static int stmfx_irq_map(struct irq_domain *d, unsigned int virq,
irq_hw_number_t hwirq)
{
irq_set_chip_data(virq, d->host_data);
irq_set_chip_and_handler(virq, &stmfx_irq_chip, handle_simple_irq);
irq_set_nested_thread(virq, 1);
irq_set_noprobe(virq);
return 0;
}
static void stmfx_irq_unmap(struct irq_domain *d, unsigned int virq)
{
irq_set_chip_and_handler(virq, NULL, NULL);
irq_set_chip_data(virq, NULL);
}
static const struct irq_domain_ops stmfx_irq_ops = {
.map = stmfx_irq_map,
.unmap = stmfx_irq_unmap,
};
static void stmfx_irq_exit(struct i2c_client *client)
{
struct stmfx *stmfx = i2c_get_clientdata(client);
int hwirq;
for (hwirq = 0; hwirq < STMFX_REG_IRQ_SRC_MAX; hwirq++)
irq_dispose_mapping(irq_find_mapping(stmfx->irq_domain, hwirq));
irq_domain_remove(stmfx->irq_domain);
}
static int stmfx_irq_init(struct i2c_client *client)
{
struct stmfx *stmfx = i2c_get_clientdata(client);
u32 irqoutpin = 0, irqtrigger;
int ret;
stmfx->irq_domain = irq_domain_add_simple(stmfx->dev->of_node,
STMFX_REG_IRQ_SRC_MAX, 0,
&stmfx_irq_ops, stmfx);
if (!stmfx->irq_domain) {
dev_err(stmfx->dev, "Failed to create IRQ domain\n");
return -EINVAL;
}
if (!of_property_read_bool(stmfx->dev->of_node, "drive-open-drain"))
irqoutpin |= STMFX_REG_IRQ_OUT_PIN_TYPE;
irqtrigger = irq_get_trigger_type(client->irq);
if ((irqtrigger & IRQ_TYPE_EDGE_RISING) ||
(irqtrigger & IRQ_TYPE_LEVEL_HIGH))
irqoutpin |= STMFX_REG_IRQ_OUT_PIN_POL;
ret = regmap_write(stmfx->map, STMFX_REG_IRQ_OUT_PIN, irqoutpin);
if (ret)
goto irq_exit;
ret = devm_request_threaded_irq(stmfx->dev, client->irq,
NULL, stmfx_irq_handler,
irqtrigger | IRQF_ONESHOT,
"stmfx", stmfx);
if (ret)
goto irq_exit;
stmfx->irq = client->irq;
return 0;
irq_exit:
stmfx_irq_exit(client);
return ret;
}
static int stmfx_chip_reset(struct stmfx *stmfx)
{
int ret;
ret = regmap_write(stmfx->map, STMFX_REG_SYS_CTRL,
STMFX_REG_SYS_CTRL_SWRST);
if (ret)
return ret;
msleep(STMFX_BOOT_TIME_MS);
return ret;
}
static int stmfx_chip_init(struct i2c_client *client)
{
struct stmfx *stmfx = i2c_get_clientdata(client);
u32 id;
u8 version[2];
int ret;
stmfx->vdd = devm_regulator_get_optional(&client->dev, "vdd");
ret = PTR_ERR_OR_ZERO(stmfx->vdd);
if (ret) {
if (ret == -ENODEV)
stmfx->vdd = NULL;
else
return dev_err_probe(&client->dev, ret, "Failed to get VDD regulator\n");
}
if (stmfx->vdd) {
ret = regulator_enable(stmfx->vdd);
if (ret) {
dev_err(&client->dev, "VDD enable failed: %d\n", ret);
return ret;
}
}
ret = regmap_read(stmfx->map, STMFX_REG_CHIP_ID, &id);
if (ret) {
dev_err(&client->dev, "Error reading chip ID: %d\n", ret);
goto err;
}
/*
* Check that ID is the complement of the I2C address:
* STMFX I2C address follows the 7-bit format (MSB), that's why
* client->addr is shifted.
*
* STMFX_I2C_ADDR| STMFX | Linux
* input pin | I2C device address | I2C device address
*---------------------------------------------------------
* 0 | b: 1000 010x h:0x84 | 0x42
* 1 | b: 1000 011x h:0x86 | 0x43
*/
if (FIELD_GET(STMFX_REG_CHIP_ID_MASK, ~id) != (client->addr << 1)) {
dev_err(&client->dev, "Unknown chip ID: %#x\n", id);
ret = -EINVAL;
goto err;
}
ret = regmap_bulk_read(stmfx->map, STMFX_REG_FW_VERSION_MSB,
version, ARRAY_SIZE(version));
if (ret) {
dev_err(&client->dev, "Error reading FW version: %d\n", ret);
goto err;
}
dev_info(&client->dev, "STMFX id: %#x, fw version: %x.%02x\n",
id, version[0], version[1]);
ret = stmfx_chip_reset(stmfx);
if (ret) {
dev_err(&client->dev, "Failed to reset chip: %d\n", ret);
goto err;
}
return 0;
err:
if (stmfx->vdd)
return regulator_disable(stmfx->vdd);
return ret;
}
static void stmfx_chip_exit(struct i2c_client *client)
{
struct stmfx *stmfx = i2c_get_clientdata(client);
regmap_write(stmfx->map, STMFX_REG_IRQ_SRC_EN, 0);
regmap_write(stmfx->map, STMFX_REG_SYS_CTRL, 0);
if (stmfx->vdd) {
int ret;
ret = regulator_disable(stmfx->vdd);
if (ret)
dev_err(&client->dev,
"Failed to disable vdd regulator: %pe\n",
ERR_PTR(ret));
}
}
static int stmfx_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct stmfx *stmfx;
int ret;
stmfx = devm_kzalloc(dev, sizeof(*stmfx), GFP_KERNEL);
if (!stmfx)
return -ENOMEM;
i2c_set_clientdata(client, stmfx);
stmfx->dev = dev;
stmfx->map = devm_regmap_init_i2c(client, &stmfx_regmap_config);
if (IS_ERR(stmfx->map)) {
ret = PTR_ERR(stmfx->map);
dev_err(dev, "Failed to allocate register map: %d\n", ret);
return ret;
}
mutex_init(&stmfx->lock);
ret = stmfx_chip_init(client);
if (ret) {
if (ret == -ETIMEDOUT)
return -EPROBE_DEFER;
return ret;
}
if (client->irq < 0) {
dev_err(dev, "Failed to get IRQ: %d\n", client->irq);
ret = client->irq;
goto err_chip_exit;
}
ret = stmfx_irq_init(client);
if (ret)
goto err_chip_exit;
ret = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
stmfx_cells, ARRAY_SIZE(stmfx_cells), NULL,
0, stmfx->irq_domain);
if (ret)
goto err_irq_exit;
return 0;
err_irq_exit:
stmfx_irq_exit(client);
err_chip_exit:
stmfx_chip_exit(client);
return ret;
}
static int stmfx_remove(struct i2c_client *client)
{
stmfx_irq_exit(client);
stmfx_chip_exit(client);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int stmfx_suspend(struct device *dev)
{
struct stmfx *stmfx = dev_get_drvdata(dev);
int ret;
ret = regmap_raw_read(stmfx->map, STMFX_REG_SYS_CTRL,
&stmfx->bkp_sysctrl, sizeof(stmfx->bkp_sysctrl));
if (ret)
return ret;
ret = regmap_raw_read(stmfx->map, STMFX_REG_IRQ_OUT_PIN,
&stmfx->bkp_irqoutpin,
sizeof(stmfx->bkp_irqoutpin));
if (ret)
return ret;
disable_irq(stmfx->irq);
if (stmfx->vdd)
return regulator_disable(stmfx->vdd);
return 0;
}
static int stmfx_resume(struct device *dev)
{
struct stmfx *stmfx = dev_get_drvdata(dev);
int ret;
if (stmfx->vdd) {
ret = regulator_enable(stmfx->vdd);
if (ret) {
dev_err(stmfx->dev,
"VDD enable failed: %d\n", ret);
return ret;
}
}
/* Reset STMFX - supply has been stopped during suspend */
ret = stmfx_chip_reset(stmfx);
if (ret) {
dev_err(stmfx->dev, "Failed to reset chip: %d\n", ret);
return ret;
}
ret = regmap_raw_write(stmfx->map, STMFX_REG_SYS_CTRL,
&stmfx->bkp_sysctrl, sizeof(stmfx->bkp_sysctrl));
if (ret)
return ret;
ret = regmap_raw_write(stmfx->map, STMFX_REG_IRQ_OUT_PIN,
&stmfx->bkp_irqoutpin,
sizeof(stmfx->bkp_irqoutpin));
if (ret)
return ret;
ret = regmap_raw_write(stmfx->map, STMFX_REG_IRQ_SRC_EN,
&stmfx->irq_src, sizeof(stmfx->irq_src));
if (ret)
return ret;
enable_irq(stmfx->irq);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(stmfx_dev_pm_ops, stmfx_suspend, stmfx_resume);
static const struct of_device_id stmfx_of_match[] = {
{ .compatible = "st,stmfx-0300", },
{},
};
MODULE_DEVICE_TABLE(of, stmfx_of_match);
static struct i2c_driver stmfx_driver = {
.driver = {
.name = "stmfx-core",
.of_match_table = stmfx_of_match,
.pm = &stmfx_dev_pm_ops,
},
.probe = stmfx_probe,
.remove = stmfx_remove,
};
module_i2c_driver(stmfx_driver);
MODULE_DESCRIPTION("STMFX core driver");
MODULE_AUTHOR("Amelie Delaunay <amelie.delaunay@st.com>");
MODULE_LICENSE("GPL v2");