Re: [PATCH v7 7/7] gpio: aspeed: Support G7 Aspeed gpio controller

[Andrew Jeffery <andrew@xxxxxxxxxxxxxxxxxxxx>]

On Tue, 2024-10-08 at 16:14 +0800, Billy Tsai wrote:
> In the 7th generation of the SoC from Aspeed, the control logic of the
> GPIO controller has been updated to support per-pin control. Each pin now
> has its own 32-bit register, allowing for individual control of the pin's
> value, direction, interrupt type, and other settings. The permission for
> coprocessor access is supported by the hardware but hasn't been
> implemented in the current patch.
> 
> Signed-off-by: Billy Tsai <billy_tsai@xxxxxxxxxxxxxx>
> ---
>  drivers/gpio/gpio-aspeed.c | 147 +++++++++++++++++++++++++++++++++++++
>  1 file changed, 147 insertions(+)
> 
> diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
> index 5d583cc9cbc7..208f95fb585e 100644
> --- a/drivers/gpio/gpio-aspeed.c
> +++ b/drivers/gpio/gpio-aspeed.c
> @@ -30,6 +30,27 @@
>  #include <linux/gpio/consumer.h>
>  #include "gpiolib.h"
>  
> +/* Non-constant mask variant of FIELD_GET() and FIELD_PREP() */
> +#define field_get(_mask, _reg)	(((_reg) & (_mask)) >> (ffs(_mask) - 1))
> +#define field_prep(_mask, _val)	(((_val) << (ffs(_mask) - 1)) & (_mask))
> +
> +#define GPIO_G7_IRQ_STS_BASE 0x100
> +#define GPIO_G7_IRQ_STS_OFFSET(x) (GPIO_G7_IRQ_STS_BASE + (x) * 0x4)
> +#define GPIO_G7_CTRL_REG_BASE 0x180
> +#define GPIO_G7_CTRL_REG_OFFSET(x) (GPIO_G7_CTRL_REG_BASE + (x) * 0x4)
> +#define GPIO_G7_CTRL_OUT_DATA BIT(0)
> +#define GPIO_G7_CTRL_DIR BIT(1)
> +#define GPIO_G7_CTRL_IRQ_EN BIT(2)
> +#define GPIO_G7_CTRL_IRQ_TYPE0 BIT(3)
> +#define GPIO_G7_CTRL_IRQ_TYPE1 BIT(4)
> +#define GPIO_G7_CTRL_IRQ_TYPE2 BIT(5)
> +#define GPIO_G7_CTRL_RST_TOLERANCE BIT(6)
> +#define GPIO_G7_CTRL_DEBOUNCE_SEL1 BIT(7)
> +#define GPIO_G7_CTRL_DEBOUNCE_SEL2 BIT(8)
> +#define GPIO_G7_CTRL_INPUT_MASK BIT(9)
> +#define GPIO_G7_CTRL_IRQ_STS BIT(12)
> +#define GPIO_G7_CTRL_IN_DATA BIT(13)
> +
>  struct aspeed_bank_props {
>  	unsigned int bank;
>  	u32 input;
> @@ -95,6 +116,22 @@ struct aspeed_gpio_bank {
>   */
>  
>  static const int debounce_timers[4] = { 0x00, 0x50, 0x54, 0x58 };
> +static const int g7_debounce_timers[4] = { 0x00, 0x00, 0x04, 0x08 };
> +
> +/*
> + * The debounce timers array is used to configure the debounce timer settings.Here’s how it works:
> + * Array Value: Indicates the offset for configuring the debounce timer.
> + * Array Index: Corresponds to the debounce setting register.
> + * The debounce timers array follows this pattern for configuring the debounce setting registers:
> + * Array Index 0: No debounce timer is set;
> + *		  Array Value is irrelevant (don’t care).
> + * Array Index 1: Debounce setting #2 is set to 1, and debounce setting #1 is set to 0.
> + *		  Array Value: offset for configuring debounce timer 0 (g4: 0x50, g7: 0x00)
> + * Array Index 2: Debounce setting #2 is set to 0, and debounce setting #1 is set to 1.
> + *		  Array Value: offset for configuring debounce timer 1 (g4: 0x54, g7: 0x04)
> + * Array Index 3: Debounce setting #2 is set to 1, and debounce setting #1 is set to 1.
> + *		  Array Value: offset for configuring debounce timer 2 (g4: 0x58, g7: 0x8)
> + */
>  
>  static const struct aspeed_gpio_copro_ops *copro_ops;
>  static void *copro_data;
> @@ -250,6 +287,39 @@ static void __iomem *aspeed_gpio_g4_bank_reg(struct aspeed_gpio *gpio,
>  	BUG();
>  }
>  
> +static u32 aspeed_gpio_g7_reg_mask(const enum aspeed_gpio_reg reg)
> +{
> +	switch (reg) {
> +	case reg_val:
> +		return GPIO_G7_CTRL_OUT_DATA;

I think a problem is that we want this to be GPIO_G7_CTRL_IN_DATA for
reads, but GPIO_G7_CTRL_OUT_DATA for writes?

> +	case reg_dir:
> +		return GPIO_G7_CTRL_DIR;
> +	case reg_irq_enable:
> +		return GPIO_G7_CTRL_IRQ_EN;
> +	case reg_irq_type0:
> +		return GPIO_G7_CTRL_IRQ_TYPE0;
> +	case reg_irq_type1:
> +		return GPIO_G7_CTRL_IRQ_TYPE1;
> +	case reg_irq_type2:
> +		return GPIO_G7_CTRL_IRQ_TYPE2;
> +	case reg_tolerance:
> +		return GPIO_G7_CTRL_RST_TOLERANCE;
> +	case reg_debounce_sel1:
> +		return GPIO_G7_CTRL_DEBOUNCE_SEL1;
> +	case reg_debounce_sel2:
> +		return GPIO_G7_CTRL_DEBOUNCE_SEL2;
> +	case reg_rdata:
> +		return GPIO_G7_CTRL_OUT_DATA;

I think this is correct regardless of the access type though.

If we can resolve the query above, the rest looks alright to me.

Andrew