u-boot/drivers/pinctrl/pinctrl-at91-pio4.c
Claudiu Beznea 8bad34a709 pinctrl: at91-pio4: add support for slew-rate
SAMA7G5 supports slew rate configuration. Adapt the driver for this.
For switching frequencies lower than 50MHz the slew rate needs to
be enabled. Since most of the pins on SAMA7G5 fall into this category
enabled the slew rate by default.

Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
2021-03-02 09:28:33 +02:00

212 lines
5.2 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/pinctrl.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/err.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;
};
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_pinctrl_set_state(struct udevice *dev, struct udevice *config)
{
struct atmel_pio4_plat *plat = dev_get_plat(dev);
struct atmel_pio4_port *bank_base;
const void *blob = gd->fdt_blob;
int node = dev_of_offset(config);
u32 offset, func, bank, line;
u32 cells[MAX_PINMUX_ENTRIES];
u32 i, conf;
int count;
conf = atmel_pinctrl_get_pinconf(config, plat);
count = fdtdec_get_int_array_count(blob, node, "pinmux",
cells, ARRAY_SIZE(cells));
if (count < 0) {
printf("%s: bad pinmux array %d\n", __func__, count);
return -EINVAL;
}
if (count > MAX_PINMUX_ENTRIES) {
printf("%s: unsupported pinmux array count %d\n",
__func__, count);
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;
}
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);
ulong priv = dev_get_driver_data(dev);
fdt_addr_t addr_base;
dev = dev_get_parent(dev);
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;
return 0;
}
static const struct udevice_id atmel_pinctrl_match[] = {
{ .compatible = "atmel,sama5d2-pinctrl" },
{ .compatible = "microchip,sama7g5-pinctrl",
.data = (ulong)1, },
{}
};
U_BOOT_DRIVER(atmel_pinctrl) = {
.name = "pinctrl_atmel_pio4",
.id = UCLASS_PINCTRL,
.of_match = atmel_pinctrl_match,
.probe = atmel_pinctrl_probe,
.plat_auto = sizeof(struct atmel_pio4_plat),
.ops = &atmel_pinctrl_ops,
};