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linux/drivers/i2c/muxes/i2c-mux-pinctrl.c
Heiner Kallweit fec1982d70 i2c: mux: Remove class argument from i2c_mux_add_adapter()
99a741aa7a2d ("i2c: mux: gpio: remove support for class-based device
instantiation") removed the last call to i2c_mux_add_adapter() with a
non-null class argument. Therefore the class argument can be removed.

Note: Class-based device instantiation is a legacy mechanism which
shouldn't be used in new code, so we can rule out that this argument
may be needed again in the future.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Peter Rosin <peda@axentia.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2024-05-13 16:13:19 +02:00

197 lines
4.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* I2C multiplexer using pinctrl API
*
* Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved.
*/
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
#include <linux/module.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/of.h>
#include "../../pinctrl/core.h"
struct i2c_mux_pinctrl {
struct pinctrl *pinctrl;
struct pinctrl_state *states[];
};
static int i2c_mux_pinctrl_select(struct i2c_mux_core *muxc, u32 chan)
{
struct i2c_mux_pinctrl *mux = i2c_mux_priv(muxc);
return pinctrl_select_state(mux->pinctrl, mux->states[chan]);
}
static int i2c_mux_pinctrl_deselect(struct i2c_mux_core *muxc, u32 chan)
{
return i2c_mux_pinctrl_select(muxc, muxc->num_adapters);
}
static struct i2c_adapter *i2c_mux_pinctrl_root_adapter(
struct pinctrl_state *state)
{
struct i2c_adapter *root = NULL;
struct pinctrl_setting *setting;
struct i2c_adapter *pin_root;
list_for_each_entry(setting, &state->settings, node) {
pin_root = i2c_root_adapter(setting->pctldev->dev);
if (!pin_root)
return NULL;
if (!root)
root = pin_root;
else if (root != pin_root)
return NULL;
}
return root;
}
static struct i2c_adapter *i2c_mux_pinctrl_parent_adapter(struct device *dev)
{
struct device_node *np = dev->of_node;
struct device_node *parent_np;
struct i2c_adapter *parent;
parent_np = of_parse_phandle(np, "i2c-parent", 0);
if (!parent_np) {
dev_err(dev, "Cannot parse i2c-parent\n");
return ERR_PTR(-ENODEV);
}
parent = of_get_i2c_adapter_by_node(parent_np);
of_node_put(parent_np);
if (!parent)
return ERR_PTR(-EPROBE_DEFER);
return parent;
}
static int i2c_mux_pinctrl_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct i2c_mux_core *muxc;
struct i2c_mux_pinctrl *mux;
struct i2c_adapter *parent;
struct i2c_adapter *root;
int num_names, i, ret;
const char *name;
num_names = of_property_count_strings(np, "pinctrl-names");
if (num_names < 0) {
dev_err(dev, "Cannot parse pinctrl-names: %d\n",
num_names);
return num_names;
}
parent = i2c_mux_pinctrl_parent_adapter(dev);
if (IS_ERR(parent))
return PTR_ERR(parent);
muxc = i2c_mux_alloc(parent, dev, num_names,
struct_size(mux, states, num_names),
0, i2c_mux_pinctrl_select, NULL);
if (!muxc) {
ret = -ENOMEM;
goto err_put_parent;
}
mux = i2c_mux_priv(muxc);
platform_set_drvdata(pdev, muxc);
mux->pinctrl = devm_pinctrl_get(dev);
if (IS_ERR(mux->pinctrl)) {
ret = PTR_ERR(mux->pinctrl);
dev_err(dev, "Cannot get pinctrl: %d\n", ret);
goto err_put_parent;
}
for (i = 0; i < num_names; i++) {
ret = of_property_read_string_index(np, "pinctrl-names", i,
&name);
if (ret < 0) {
dev_err(dev, "Cannot parse pinctrl-names: %d\n", ret);
goto err_put_parent;
}
mux->states[i] = pinctrl_lookup_state(mux->pinctrl, name);
if (IS_ERR(mux->states[i])) {
ret = PTR_ERR(mux->states[i]);
dev_err(dev, "Cannot look up pinctrl state %s: %d\n",
name, ret);
goto err_put_parent;
}
if (strcmp(name, "idle"))
continue;
if (i != num_names - 1) {
dev_err(dev, "idle state must be last\n");
ret = -EINVAL;
goto err_put_parent;
}
muxc->deselect = i2c_mux_pinctrl_deselect;
}
root = i2c_root_adapter(&muxc->parent->dev);
muxc->mux_locked = true;
for (i = 0; i < num_names; i++) {
if (root != i2c_mux_pinctrl_root_adapter(mux->states[i])) {
muxc->mux_locked = false;
break;
}
}
if (muxc->mux_locked)
dev_info(dev, "mux-locked i2c mux\n");
/* Do not add any adapter for the idle state (if it's there at all). */
for (i = 0; i < num_names - !!muxc->deselect; i++) {
ret = i2c_mux_add_adapter(muxc, 0, i);
if (ret)
goto err_del_adapter;
}
return 0;
err_del_adapter:
i2c_mux_del_adapters(muxc);
err_put_parent:
i2c_put_adapter(parent);
return ret;
}
static void i2c_mux_pinctrl_remove(struct platform_device *pdev)
{
struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
i2c_mux_del_adapters(muxc);
i2c_put_adapter(muxc->parent);
}
static const struct of_device_id i2c_mux_pinctrl_of_match[] = {
{ .compatible = "i2c-mux-pinctrl", },
{},
};
MODULE_DEVICE_TABLE(of, i2c_mux_pinctrl_of_match);
static struct platform_driver i2c_mux_pinctrl_driver = {
.driver = {
.name = "i2c-mux-pinctrl",
.of_match_table = i2c_mux_pinctrl_of_match,
},
.probe = i2c_mux_pinctrl_probe,
.remove_new = i2c_mux_pinctrl_remove,
};
module_platform_driver(i2c_mux_pinctrl_driver);
MODULE_DESCRIPTION("pinctrl-based I2C multiplexer driver");
MODULE_AUTHOR("Stephen Warren <swarren@nvidia.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:i2c-mux-pinctrl");