blob: b9868505a3be5bcec0e0612475b4e6d44c0f6966 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* MMIO register bitfield-controlled multiplexer driver
* Based on the linux mmio multiplexer driver
*
* Copyright (C) 2017 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
* Copyright (C) 2019 Texas Instrument, Jean-jacques Hiblot <jjhiblot@ti.com>
*/
#include <common.h>
#include <dm.h>
#include <mux-internal.h>
#include <regmap.h>
#include <syscon.h>
#include <dm/device.h>
#include <dm/device_compat.h>
#include <dm/read.h>
#include <dm/devres.h>
#include <dt-bindings/mux/mux.h>
#include <linux/bitops.h>
static int mux_mmio_set(struct mux_control *mux, int state)
{
struct regmap_field **fields = dev_get_priv(mux->dev);
return regmap_field_write(fields[mux_control_get_index(mux)], state);
}
static const struct mux_control_ops mux_mmio_ops = {
.set = mux_mmio_set,
};
static const struct udevice_id mmio_mux_of_match[] = {
{ .compatible = "mmio-mux" },
{ /* sentinel */ },
};
static int mmio_mux_probe(struct udevice *dev)
{
struct regmap_field **fields;
struct mux_chip *mux_chip = dev_get_uclass_priv(dev);
struct regmap *regmap;
u32 *mux_reg_masks;
u32 *idle_states;
int num_fields;
int ret;
int i;
regmap = syscon_node_to_regmap(dev_ofnode(dev->parent));
if (IS_ERR(regmap)) {
ret = PTR_ERR(regmap);
dev_err(dev, "failed to get regmap: %d\n", ret);
return ret;
}
num_fields = dev_read_size(dev, "mux-reg-masks");
if (num_fields < 0)
return log_msg_ret("mux-reg-masks missing", -EINVAL);
num_fields /= sizeof(u32);
if (num_fields == 0 || num_fields % 2)
ret = -EINVAL;
num_fields = num_fields / 2;
ret = mux_alloc_controllers(dev, num_fields);
if (ret < 0)
return log_msg_ret("mux_alloc_controllers", ret);
fields = devm_kmalloc(dev, num_fields * sizeof(*fields), __GFP_ZERO);
if (!fields)
return -ENOMEM;
dev->priv = fields;
mux_reg_masks = devm_kmalloc(dev, num_fields * 2 * sizeof(u32),
__GFP_ZERO);
if (!mux_reg_masks)
return -ENOMEM;
ret = dev_read_u32_array(dev, "mux-reg-masks", mux_reg_masks,
num_fields * 2);
if (ret < 0)
return log_msg_ret("mux-reg-masks read", ret);
idle_states = devm_kmalloc(dev, num_fields * sizeof(u32), __GFP_ZERO);
if (!idle_states)
return -ENOMEM;
ret = dev_read_u32_array(dev, "idle-states", idle_states, num_fields);
if (ret < 0) {
log_err("idle-states");
devm_kfree(dev, idle_states);
idle_states = NULL;
}
for (i = 0; i < num_fields; i++) {
struct mux_control *mux = &mux_chip->mux[i];
struct reg_field field;
u32 reg, mask;
int bits;
reg = mux_reg_masks[2 * i];
mask = mux_reg_masks[2 * i + 1];
field.reg = reg;
field.msb = fls(mask) - 1;
field.lsb = ffs(mask) - 1;
if (mask != GENMASK(field.msb, field.lsb))
return log_msg_ret("invalid mask", -EINVAL);
fields[i] = devm_regmap_field_alloc(dev, regmap, field);
if (IS_ERR(fields[i])) {
ret = PTR_ERR(fields[i]);
return log_msg_ret("regmap_field_alloc", ret);
}
bits = 1 + field.msb - field.lsb;
mux->states = 1 << bits;
if (!idle_states)
continue;
if (idle_states[i] != MUX_IDLE_AS_IS &&
idle_states[i] >= mux->states)
return log_msg_ret("idle-states range", -EINVAL);
mux->idle_state = idle_states[i];
}
devm_kfree(dev, mux_reg_masks);
if (idle_states)
devm_kfree(dev, idle_states);
return 0;
}
U_BOOT_DRIVER(mmio_mux) = {
.name = "mmio-mux",
.id = UCLASS_MUX,
.of_match = mmio_mux_of_match,
.probe = mmio_mux_probe,
.ops = &mux_mmio_ops,
};