u-boot/drivers/pinctrl/pinctrl-at91-pio4.c
Sergiu Moga 7086defa04 pinctrl: at91-pio4: Add support for pinctrl config subnodes
Previously, in order for the `pinctrl-*` DT node properties
to be properly processed, the pinctrl's subnodes were limited
to only having the `pinmux` property as well as other additional
properties (slew-rate, bias-disable, etc.). Now, with this patch
the pinctrl driver is made to work similarly to the one from Linux.
It can now distinguish between one subnode and a subnode with multiple
subnodes.

Signed-off-by: Sergiu Moga <sergiu.moga@microchip.com>
2022-09-19 09:51:04 +03:00

316 lines
8.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Atmel PIO4 pinctrl driver
*
* Copyright (C) 2016 Atmel Corporation
* Wenyou.Yang <wenyou.yang@atmel.com>
*/
#include <common.h>
#include <dm.h>
#include <asm/global_data.h>
#include <dm/device-internal.h>
#include <dm/lists.h>
#include <dm/pinctrl.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/err.h>
#include <dm/uclass-internal.h>
#include <mach/atmel_pio4.h>
DECLARE_GLOBAL_DATA_PTR;
/*
* Warning:
* In order to not introduce confusion between Atmel PIO groups and pinctrl
* framework groups, Atmel PIO groups will be called banks.
*/
struct atmel_pio4_plat {
struct atmel_pio4_port *reg_base;
unsigned int slew_rate_support;
};
/*
* Table keeping track of the pinctrl driver's slew rate support and the
* corresponding index into the struct udevice_id of the gpio_atmel_pio4 GPIO
* driver. This has been done in order to align the DT of U-Boot with the DT of
* Linux. In Linux, a phandle from a '-gpio' DT property is linked to the
* pinctrl driver, unlike U-Boot which redirects this phandle to a corresponding
* UCLASS_GPIO driver. Thus, in order to link the two, a hook to the bind method
* of the pinctrl driver in U-Boot has been added. This bind method will attach
* the GPIO driver to the pinctrl DT node using this table.
* @slew_rate_support pinctrl driver's slew rate support
* @gdidx index into the GPIO driver's struct udevide_id
* (needed in order to properly bind with driver_data)
*/
struct atmel_pinctrl_data {
unsigned int slew_rate_support;
int gdidx;
};
static const struct pinconf_param conf_params[] = {
{ "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 },
{ "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 },
{ "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 },
{ "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 },
{ "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 },
{ "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 },
{ "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 },
{ "atmel,drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 },
{ "slew-rate", PIN_CONFIG_SLEW_RATE, 0},
};
static u32 atmel_pinctrl_get_pinconf(struct udevice *config,
struct atmel_pio4_plat *plat)
{
const struct pinconf_param *params;
u32 param, arg, conf = 0;
u32 i;
u32 val;
for (i = 0; i < ARRAY_SIZE(conf_params); i++) {
params = &conf_params[i];
if (!dev_read_prop(config, params->property, NULL))
continue;
param = params->param;
arg = params->default_value;
/* Keep slew rate enabled by default. */
if (plat->slew_rate_support)
conf |= ATMEL_PIO_SR;
switch (param) {
case PIN_CONFIG_BIAS_DISABLE:
conf &= (~ATMEL_PIO_PUEN_MASK);
conf &= (~ATMEL_PIO_PDEN_MASK);
break;
case PIN_CONFIG_BIAS_PULL_UP:
conf |= ATMEL_PIO_PUEN_MASK;
break;
case PIN_CONFIG_BIAS_PULL_DOWN:
conf |= ATMEL_PIO_PDEN_MASK;
break;
case PIN_CONFIG_DRIVE_OPEN_DRAIN:
if (arg == 0)
conf &= (~ATMEL_PIO_OPD_MASK);
else
conf |= ATMEL_PIO_OPD_MASK;
break;
case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
if (arg == 0)
conf |= ATMEL_PIO_SCHMITT_MASK;
else
conf &= (~ATMEL_PIO_SCHMITT_MASK);
break;
case PIN_CONFIG_INPUT_DEBOUNCE:
if (arg == 0) {
conf &= (~ATMEL_PIO_IFEN_MASK);
conf &= (~ATMEL_PIO_IFSCEN_MASK);
} else {
conf |= ATMEL_PIO_IFEN_MASK;
conf |= ATMEL_PIO_IFSCEN_MASK;
}
break;
case PIN_CONFIG_DRIVE_STRENGTH:
dev_read_u32(config, params->property, &val);
conf &= (~ATMEL_PIO_DRVSTR_MASK);
conf |= (val << ATMEL_PIO_DRVSTR_OFFSET)
& ATMEL_PIO_DRVSTR_MASK;
break;
case PIN_CONFIG_SLEW_RATE:
if (!plat->slew_rate_support)
break;
dev_read_u32(config, params->property, &val);
/* And disable it if requested. */
if (val == 0)
conf &= ~ATMEL_PIO_SR;
break;
default:
printf("%s: Unsupported configuration parameter: %u\n",
__func__, param);
break;
}
}
return conf;
}
static inline struct atmel_pio4_port *atmel_pio4_bank_base(struct udevice *dev,
u32 bank)
{
struct atmel_pio4_plat *plat = dev_get_plat(dev);
struct atmel_pio4_port *bank_base =
(struct atmel_pio4_port *)((u32)plat->reg_base +
ATMEL_PIO_BANK_OFFSET * bank);
return bank_base;
}
#define MAX_PINMUX_ENTRIES 40
static int atmel_process_config_dev(struct udevice *dev, struct udevice *config)
{
struct atmel_pio4_plat *plat = dev_get_plat(dev);
int node = dev_of_offset(config);
struct atmel_pio4_port *bank_base;
u32 offset, func, bank, line;
u32 cells[MAX_PINMUX_ENTRIES];
u32 i, conf;
int count;
conf = atmel_pinctrl_get_pinconf(config, plat);
/*
* The only case where this function returns a negative error value
* is when there is no "pinmux" property attached to this node
*/
count = fdtdec_get_int_array_count(gd->fdt_blob, node, "pinmux",
cells, ARRAY_SIZE(cells));
if (count < 0)
return count;
if (count > MAX_PINMUX_ENTRIES)
return -EINVAL;
for (i = 0 ; i < count; i++) {
offset = ATMEL_GET_PIN_NO(cells[i]);
func = ATMEL_GET_PIN_FUNC(cells[i]);
bank = ATMEL_PIO_BANK(offset);
line = ATMEL_PIO_LINE(offset);
bank_base = atmel_pio4_bank_base(dev, bank);
writel(BIT(line), &bank_base->mskr);
conf &= (~ATMEL_PIO_CFGR_FUNC_MASK);
conf |= (func & ATMEL_PIO_CFGR_FUNC_MASK);
writel(conf, &bank_base->cfgr);
}
return 0;
}
static int atmel_pinctrl_set_state(struct udevice *dev, struct udevice *config)
{
int node = dev_of_offset(config);
struct udevice *subconfig;
int subnode, subnode_count = 0, ret;
/*
* If this function returns a negative error code then that means
* that either the "pinmux" property of the node is missing, which is
* the case for pinctrl nodes that do not have all the pins with the
* same configuration and are split in multiple subnodes, or something
* else went wrong and we have to stop. For the latter case, it would
* mean that the node failed even though it has no subnodes.
*/
ret = atmel_process_config_dev(dev, config);
if (!ret)
return ret;
/*
* If we reach here, it means that the subnode pinctrl's DT has multiple
* subnodes. If it does not, then something else went wrong in the
* previous call to atmel_process_config_dev.
*/
fdt_for_each_subnode(subnode, gd->fdt_blob, node) {
/* Get subnode as an udevice */
ret = uclass_find_device_by_of_offset(UCLASS_PINCONFIG, subnode,
&subconfig);
if (ret)
return ret;
/*
* If this time the function returns an error code on a subnode
* then something is totally wrong so abort.
*/
ret = atmel_process_config_dev(dev, subconfig);
if (ret)
return ret;
subnode_count++;
}
/*
* If we somehow got here and we do not have any subnodes, abort.
*/
if (!subnode_count)
return -EINVAL;
return 0;
}
const struct pinctrl_ops atmel_pinctrl_ops = {
.set_state = atmel_pinctrl_set_state,
};
static int atmel_pinctrl_probe(struct udevice *dev)
{
struct atmel_pio4_plat *plat = dev_get_plat(dev);
struct atmel_pinctrl_data *priv = (struct atmel_pinctrl_data *)dev_get_driver_data(dev);
fdt_addr_t addr_base;
addr_base = dev_read_addr(dev);
if (addr_base == FDT_ADDR_T_NONE)
return -EINVAL;
plat->reg_base = (struct atmel_pio4_port *)addr_base;
plat->slew_rate_support = priv->slew_rate_support;
return 0;
}
static int atmel_pinctrl_bind(struct udevice *dev)
{
struct udevice *g;
struct driver *drv;
ofnode node = dev_ofnode(dev);
struct atmel_pinctrl_data *priv = (struct atmel_pinctrl_data *)dev_get_driver_data(dev);
if (!CONFIG_IS_ENABLED(ATMEL_PIO4))
return 0;
/* Obtain a handle to the GPIO driver */
drv = lists_driver_lookup_name("gpio_atmel_pio4");
if (!drv)
return -ENOENT;
/*
* Bind the GPIO driver to the pinctrl DT node, together
* with its corresponding driver_data.
*/
return device_bind_with_driver_data(dev, drv, drv->name,
drv->of_match[priv->gdidx].data,
node, &g);
}
static const struct atmel_pinctrl_data atmel_sama5d2_pinctrl_data = {
.gdidx = 0,
};
static const struct atmel_pinctrl_data microchip_sama7g5_pinctrl_data = {
.slew_rate_support = 1,
.gdidx = 1,
};
static const struct udevice_id atmel_pinctrl_match[] = {
{ .compatible = "atmel,sama5d2-pinctrl",
.data = (ulong)&atmel_sama5d2_pinctrl_data, },
{ .compatible = "microchip,sama7g5-pinctrl",
.data = (ulong)&microchip_sama7g5_pinctrl_data, },
{}
};
U_BOOT_DRIVER(atmel_pinctrl) = {
.name = "pinctrl_atmel_pio4",
.id = UCLASS_PINCTRL,
.of_match = atmel_pinctrl_match,
.bind = atmel_pinctrl_bind,
.probe = atmel_pinctrl_probe,
.plat_auto = sizeof(struct atmel_pio4_plat),
.ops = &atmel_pinctrl_ops,
};