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pinctrl: bcm2835: Add support for BCM2711 pull-up functionality

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The BCM2711 has a new way of selecting the pull-up/pull-down setting
for a GPIO pin. The registers used for the BCM2835, GP_PUD and
GP_PUDCLKn0, are no longer connected. A new set of registers,
GP_GPIO_PUP_PDN_CNTRL_REGx must be used. This commit will add
a new compatible string "brcm,bcm2711-gpio" and the kernel
driver will use it to select which method is used to select
pull-up/pull-down.

This patch based on a patch by Al Cooper which was intended for the
BCM7211. This is a bugfixed and improved version.

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Link: https://lore.kernel.org/r/1563776607-8368-3-git-send-email-wahrenst@gmx.net
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Stefan Wahren 2019-07-22 08:23:25 +02:00 committed by Linus Walleij
parent 9cd6237d66
commit e38a9a437f
1 changed files with 100 additions and 5 deletions
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105
drivers/pinctrl/bcm/pinctrl-bcm2835.c
View File

@ -57,15 +57,24 @@
#define GPAFEN0 0x88 /* Pin Async Falling Edge Detect */
#define GPPUD 0x94 /* Pin Pull-up/down Enable */
#define GPPUDCLK0 0x98 /* Pin Pull-up/down Enable Clock */
#define GP_GPIO_PUP_PDN_CNTRL_REG0 0xe4 /* 2711 Pin Pull-up/down select */
#define FSEL_REG(p) (GPFSEL0 + (((p) / 10) * 4))
#define FSEL_SHIFT(p) (((p) % 10) * 3)
#define GPIO_REG_OFFSET(p) ((p) / 32)
#define GPIO_REG_SHIFT(p) ((p) % 32)
#define PUD_2711_MASK 0x3
#define PUD_2711_REG_OFFSET(p) ((p) / 16)
#define PUD_2711_REG_SHIFT(p) (((p) % 16) * 2)
/* argument: bcm2835_pinconf_pull */
#define BCM2835_PINCONF_PARAM_PULL (PIN_CONFIG_END + 1)
#define BCM2711_PULL_NONE 0x0
#define BCM2711_PULL_UP 0x1
#define BCM2711_PULL_DOWN 0x2
struct bcm2835_pinctrl {
struct device *dev;
void __iomem *base;
@ -975,6 +984,77 @@ static const struct pinconf_ops bcm2835_pinconf_ops = {
.pin_config_set = bcm2835_pinconf_set,
};
static void bcm2711_pull_config_set(struct bcm2835_pinctrl *pc,
unsigned int pin, unsigned int arg)
{
u32 shifter;
u32 value;
u32 off;
off = PUD_2711_REG_OFFSET(pin);
shifter = PUD_2711_REG_SHIFT(pin);
value = bcm2835_gpio_rd(pc, GP_GPIO_PUP_PDN_CNTRL_REG0 + (off * 4));
value &= ~(PUD_2711_MASK << shifter);
value |= (arg << shifter);
bcm2835_gpio_wr(pc, GP_GPIO_PUP_PDN_CNTRL_REG0 + (off * 4), value);
}
static int bcm2711_pinconf_set(struct pinctrl_dev *pctldev,
unsigned int pin, unsigned long *configs,
unsigned int num_configs)
{
struct bcm2835_pinctrl *pc = pinctrl_dev_get_drvdata(pctldev);
u32 param, arg;
int i;
for (i = 0; i < num_configs; i++) {
param = pinconf_to_config_param(configs[i]);
arg = pinconf_to_config_argument(configs[i]);
switch (param) {
/* convert legacy brcm,pull */
case BCM2835_PINCONF_PARAM_PULL:
if (arg == BCM2835_PUD_UP)
arg = BCM2711_PULL_UP;
else if (arg == BCM2835_PUD_DOWN)
arg = BCM2711_PULL_DOWN;
else
arg = BCM2711_PULL_NONE;
bcm2711_pull_config_set(pc, pin, arg);
break;
/* Set pull generic bindings */
case PIN_CONFIG_BIAS_DISABLE:
bcm2711_pull_config_set(pc, pin, BCM2711_PULL_NONE);
break;
case PIN_CONFIG_BIAS_PULL_DOWN:
bcm2711_pull_config_set(pc, pin, BCM2711_PULL_DOWN);
break;
case PIN_CONFIG_BIAS_PULL_UP:
bcm2711_pull_config_set(pc, pin, BCM2711_PULL_UP);
break;
/* Set output-high or output-low */
case PIN_CONFIG_OUTPUT:
bcm2835_gpio_set_bit(pc, arg ? GPSET0 : GPCLR0, pin);
break;
default:
return -ENOTSUPP;
}
} /* for each config */
return 0;
}
static const struct pinconf_ops bcm2711_pinconf_ops = {
.is_generic = true,
.pin_config_get = bcm2835_pinconf_get,
.pin_config_set = bcm2711_pinconf_set,
};
static struct pinctrl_desc bcm2835_pinctrl_desc = {
.name = MODULE_NAME,
.pins = bcm2835_gpio_pins,
@ -990,6 +1070,18 @@ static struct pinctrl_gpio_range bcm2835_pinctrl_gpio_range = {
.npins = BCM2835_NUM_GPIOS,
};
static const struct of_device_id bcm2835_pinctrl_match[] = {
{
.compatible = "brcm,bcm2835-gpio",
.data = &bcm2835_pinconf_ops,
},
{
.compatible = "brcm,bcm2711-gpio",
.data = &bcm2711_pinconf_ops,
},
{}
};
static int bcm2835_pinctrl_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@ -997,6 +1089,8 @@ static int bcm2835_pinctrl_probe(struct platform_device *pdev)
struct bcm2835_pinctrl *pc;
struct resource iomem;
int err, i;
const struct of_device_id *match;
BUILD_BUG_ON(ARRAY_SIZE(bcm2835_gpio_pins) != BCM2835_NUM_GPIOS);
BUILD_BUG_ON(ARRAY_SIZE(bcm2835_gpio_groups) != BCM2835_NUM_GPIOS);
@ -1073,6 +1167,12 @@ static int bcm2835_pinctrl_probe(struct platform_device *pdev)
bcm2835_gpio_irq_handler);
}
match = of_match_node(bcm2835_pinctrl_match, pdev->dev.of_node);
if (match) {
bcm2835_pinctrl_desc.confops =
(const struct pinconf_ops *)match->data;
}
pc->pctl_dev = devm_pinctrl_register(dev, &bcm2835_pinctrl_desc, pc);
if (IS_ERR(pc->pctl_dev)) {
gpiochip_remove(&pc->gpio_chip);
@ -1087,11 +1187,6 @@ static int bcm2835_pinctrl_probe(struct platform_device *pdev)
return 0;
}
static const struct of_device_id bcm2835_pinctrl_match[] = {
{ .compatible = "brcm,bcm2835-gpio" },
{}
};
static struct platform_driver bcm2835_pinctrl_driver = {
.probe = bcm2835_pinctrl_probe,
.driver = {