[RFC PATCH 5/5] gpio: aspeed: Add support for reset tolerance

Andrew Jeffery
2017-10-20T03:37:27Z

Use the new pinconf parameter for reset tolerance to expose the
associated capability of the Aspeed GPIO controller.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
---
drivers/gpio/gpio-aspeed.c | 39 +++++++++++++++++++++++++++++++++++++--
1 file changed, 37 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
index bfc53995064a..0492cd917178 100644
--- a/drivers/gpio/gpio-aspeed.c
+++ b/drivers/gpio/gpio-aspeed.c
@@ -60,6 +60,7 @@ struct aspeed_gpio_bank {
uint16_t val_regs;
uint16_t irq_regs;
uint16_t debounce_regs;
+ uint16_t tolerance_regs;
const char names[4][3];
};

@@ -70,48 +71,56 @@ static const struct aspeed_gpio_bank aspeed_gpio_banks[] = {
.val_regs = 0x0000,
.irq_regs = 0x0008,
.debounce_regs = 0x0040,
+ .tolerance_regs = 0x001c,
.names = { "A", "B", "C", "D" },
},
{
.val_regs = 0x0020,
.irq_regs = 0x0028,
.debounce_regs = 0x0048,
+ .tolerance_regs = 0x003c,
.names = { "E", "F", "G", "H" },
},
{
.val_regs = 0x0070,
.irq_regs = 0x0098,
.debounce_regs = 0x00b0,
+ .tolerance_regs = 0x00ac,
.names = { "I", "J", "K", "L" },
},
{
.val_regs = 0x0078,
.irq_regs = 0x00e8,
.debounce_regs = 0x0100,
+ .tolerance_regs = 0x00fc,
.names = { "M", "N", "O", "P" },
},
{
.val_regs = 0x0080,
.irq_regs = 0x0118,
.debounce_regs = 0x0130,
+ .tolerance_regs = 0x012c,
.names = { "Q", "R", "S", "T" },
},
{
.val_regs = 0x0088,
.irq_regs = 0x0148,
.debounce_regs = 0x0160,
+ .tolerance_regs = 0x015c,
.names = { "U", "V", "W", "X" },
},
{
.val_regs = 0x01E0,
.irq_regs = 0x0178,
.debounce_regs = 0x0190,
+ .tolerance_regs = 0x018c,
.names = { "Y", "Z", "AA", "AB" },
},
{
- .val_regs = 0x01E8,
- .irq_regs = 0x01A8,
+ .val_regs = 0x01e8,
+ .irq_regs = 0x01a8,
.debounce_regs = 0x01c0,
+ .tolerance_regs = 0x01bc,
.names = { "AC", "", "", "" },
},
};
@@ -531,6 +540,30 @@ static int aspeed_gpio_setup_irqs(struct aspeed_gpio *gpio,
return 0;
}

+static int aspeed_gpio_reset_tolerance(struct gpio_chip *chip,
+ unsigned int offset, bool enable)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+ const struct aspeed_gpio_bank *bank;
+ unsigned long flags;
+ u32 val;
+
+ bank = to_bank(offset);
+
+ spin_lock_irqsave(&gpio->lock, flags);
+ val = readl(gpio->base + bank->tolerance_regs);
+
+ if (enable)
+ val |= GPIO_BIT(offset);
+ else
+ val &= ~GPIO_BIT(offset);
+
+ writel(val, gpio->base + bank->tolerance_regs);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return 0;
+}
+
static int aspeed_gpio_request(struct gpio_chip *chip, unsigned int offset)
{
if (!have_gpio(gpiochip_get_data(chip), offset))
@@ -768,6 +801,8 @@ static int aspeed_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
param == PIN_CONFIG_DRIVE_OPEN_SOURCE)
/* Return -ENOTSUPP to trigger emulation, as per datasheet */
return -ENOTSUPP;
+ else if (param == PIN_CONFIG_RESET_TOLERANT)
+ return aspeed_gpio_reset_tolerance(chip, offset, arg);

return -ENOTSUPP;
}
--
2.11.0