[PATCH v3 4/5] gpio: gpio-aspeed-sgpio: Add set_config function

From: Steven Lee
Date: Thu Jun 03 2021 - 06:18:55 EST


AST SoC supports *retain pin state* function when wdt reset.
The patch adds set_config function for handling sgpio reset tolerance
register.

Signed-off-by: Steven Lee <steven_lee@xxxxxxxxxxxxxx>
---
drivers/gpio/gpio-aspeed-sgpio.c | 54 +++++++++++++++++++++++++++++---
1 file changed, 50 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpio-aspeed-sgpio.c b/drivers/gpio/gpio-aspeed-sgpio.c
index aa894c92143e..8003308811f7 100644
--- a/drivers/gpio/gpio-aspeed-sgpio.c
+++ b/drivers/gpio/gpio-aspeed-sgpio.c
@@ -52,9 +52,10 @@ struct aspeed_sgpio {
};

struct aspeed_sgpio_bank {
- uint16_t val_regs;
- uint16_t rdata_reg;
- uint16_t irq_regs;
+ u16 val_regs;
+ u16 rdata_reg;
+ u16 irq_regs;
+ u16 tolerance_regs;
const char names[4][3];
};

@@ -70,24 +71,28 @@ static const struct aspeed_sgpio_bank aspeed_sgpio_banks[] = {
.val_regs = 0x0000,
.rdata_reg = 0x0070,
.irq_regs = 0x0004,
+ .tolerance_regs = 0x0018,
.names = { "A", "B", "C", "D" },
},
{
.val_regs = 0x001C,
.rdata_reg = 0x0074,
.irq_regs = 0x0020,
+ .tolerance_regs = 0x0034,
.names = { "E", "F", "G", "H" },
},
{
.val_regs = 0x0038,
.rdata_reg = 0x0078,
.irq_regs = 0x003C,
+ .tolerance_regs = 0x0050,
.names = { "I", "J", "K", "L" },
},
{
.val_regs = 0x0090,
.rdata_reg = 0x007C,
.irq_regs = 0x0094,
+ .tolerance_regs = 0x00A8,
.names = { "M", "N", "O", "P" },
},
};
@@ -100,6 +105,7 @@ enum aspeed_sgpio_reg {
reg_irq_type1,
reg_irq_type2,
reg_irq_status,
+ reg_tolerance,
};

#define GPIO_VAL_VALUE 0x00
@@ -128,6 +134,8 @@ static void __iomem *bank_reg(struct aspeed_sgpio *gpio,
return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE2;
case reg_irq_status:
return gpio->base + bank->irq_regs + GPIO_IRQ_STATUS;
+ case reg_tolerance:
+ return gpio->base + bank->tolerance_regs;
default:
/* acturally if code runs to here, it's an error case */
BUG();
@@ -484,6 +492,44 @@ static int aspeed_sgpio_setup_irqs(struct aspeed_sgpio *gpio,
return 0;
}

+static int aspeed_sgpio_reset_tolerance(struct gpio_chip *chip,
+ unsigned int offset, bool enable)
+{
+ struct aspeed_sgpio *gpio = gpiochip_get_data(chip);
+ unsigned long flags;
+ void __iomem *reg;
+ u32 val;
+
+ reg = bank_reg(gpio, to_bank(offset, gpio), reg_tolerance);
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ val = readl(reg);
+
+ if (enable)
+ val |= GPIO_BIT(offset, gpio);
+ else
+ val &= ~GPIO_BIT(offset, gpio);
+
+ writel(val, reg);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return 0;
+}
+
+static int aspeed_sgpio_set_config(struct gpio_chip *chip, unsigned int offset,
+ unsigned long config)
+{
+ unsigned long param = pinconf_to_config_param(config);
+ u32 arg = pinconf_to_config_argument(config);
+
+ if (param == PIN_CONFIG_PERSIST_STATE)
+ return aspeed_sgpio_reset_tolerance(chip, offset, arg);
+ else
+ return -EOPNOTSUPP;
+}
+
static const struct aspeed_sgpio_pdata ast2600_sgpiom1_pdata = {
.max_ngpios = 128,
.pin_mask = GENMASK(10, 6),
@@ -591,7 +637,7 @@ static int __init aspeed_sgpio_probe(struct platform_device *pdev)
gpio->chip.free = NULL;
gpio->chip.get = aspeed_sgpio_get;
gpio->chip.set = aspeed_sgpio_set;
- gpio->chip.set_config = NULL;
+ gpio->chip.set_config = aspeed_sgpio_set_config;
gpio->chip.label = dev_name(&pdev->dev);
gpio->chip.base = -1;

--
2.17.1