[PATCH v3 13/20] pinctrl: samsung: Add filter selection support for alive banks
William McVicker
willmcvicker at google.com
Wed Oct 11 14:51:42 PDT 2023
On 10/11/2023, Peter Griffin wrote:
> Newer Exynos SoCs have a filter selection register on alive bank pins.
> This allows the selection of a digital or delay filter for each pin. If
> the filter selection register is not available then the default filter
> (digital) is applied.
>
> On suspend we apply the analog filter to all pins in the bank, and on
> resume the digital filter is reapplied to all pins in the bank.
>
> Signed-off-by: Peter Griffin <peter.griffin at linaro.org>
Tested-by: Will McVicker <willmcvicker at google.com>
Thanks,
Will
> ---
> drivers/pinctrl/samsung/pinctrl-exynos.c | 82 ++++++++++++++++++++++-
> drivers/pinctrl/samsung/pinctrl-exynos.h | 7 ++
> drivers/pinctrl/samsung/pinctrl-samsung.c | 2 +
> drivers/pinctrl/samsung/pinctrl-samsung.h | 23 +++++++
> 4 files changed, 113 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pinctrl/samsung/pinctrl-exynos.c b/drivers/pinctrl/samsung/pinctrl-exynos.c
> index a8212fc126bf..800831aa8357 100644
> --- a/drivers/pinctrl/samsung/pinctrl-exynos.c
> +++ b/drivers/pinctrl/samsung/pinctrl-exynos.c
> @@ -269,6 +269,68 @@ struct exynos_eint_gpio_save {
> u32 eint_mask;
> };
>
> +static void exynos_eint_flt_config(struct samsung_pinctrl_drv_data *d,
> + struct samsung_pin_bank *bank, int filter)
> +{
> + unsigned int flt_reg, flt_con = 0;
> + unsigned int val, shift;
> + int i;
> + int loop_cnt;
> +
> + /*
> + * This function sets the desired filter (digital or delay) to
> + * every pin in the bank. Note the filter selection bitfield is
> + * only found on alive banks. The FLTCON register has the
> + * following layout
> + *
> + * BitfieldName[PinNum][Bit:Bit]
> + *
> + * FLT_EN[3][31] FLT_SEL[3][30] FLT_WIDTH[3][29:24]
> + * FLT_EN[2][23] FLT_SEL[2][22] FLT_WIDTH[2][21:16]
> + * FLT_EN[1][15] FLT_SEL[1][14] FLT_WIDTH[1][13:8]
> + * FLT_EN[0][7] FLT_SEL[0][6] FLT_WIDTH[0][5:0]
> + */
> +
> + flt_con |= EXYNOS9_FLTCON_EN;
> +
> + if (filter)
> + flt_con |= EXYNOS9_FLTCON_SEL_DIGITAL;
> +
> + flt_reg = EXYNOS_GPIO_EFLTCON_OFFSET + bank->fltcon_offset;
> +
> + if (bank->nr_pins > EXYNOS9_FLTCON_NR_PIN)
> + /*
> + * if nr_pins > 4, we should set FLTCON0 register fully.
> + * (pin0 ~ 3). So loop 4 times in case of FLTCON0.
> + */
> + loop_cnt = EXYNOS9_FLTCON_NR_PIN;
> + else
> + loop_cnt = bank->nr_pins;
> +
> + val = readl(d->virt_base + flt_reg);
> +
> + for (i = 0; i < loop_cnt; i++) {
> + shift = i * EXYNOS9_FLTCON_LEN;
> + val &= ~(EXYNOS9_FLTCON_MASK << shift);
> + val |= (flt_con << shift);
> + }
> +
> + writel(val, d->virt_base + flt_reg);
> +
> + /* loop for FLTCON1 pin 4 ~ 7 */
> + if (bank->nr_pins > EXYNOS9_FLTCON_NR_PIN) {
> + val = readl(d->virt_base + flt_reg + 0x4);
> + loop_cnt = (bank->nr_pins - EXYNOS9_FLTCON_NR_PIN);
> +
> + for (i = 0; i < loop_cnt; i++) {
> + shift = i * EXYNOS9_FLTCON_LEN;
> + val &= ~(EXYNOS9_FLTCON_MASK << shift);
> + val |= (flt_con << shift);
> + }
> + writel(val, d->virt_base + flt_reg + 0x4);
> + }
> +}
> +
> /*
> * exynos_eint_gpio_init() - setup handling of external gpio interrupts.
> * @d: driver data of samsung pinctrl driver.
> @@ -321,6 +383,9 @@ __init int exynos_eint_gpio_init(struct samsung_pinctrl_drv_data *d)
> goto err_domains;
> }
>
> + /* Set Delay Analog Filter */
> + if (bank->fltcon_type != FLT_DEFAULT)
> + exynos_eint_flt_config(d, bank, EXYNOS9_FLTCON_SEL_DELAY);
> }
>
> return 0;
> @@ -555,6 +620,10 @@ __init int exynos_eint_wkup_init(struct samsung_pinctrl_drv_data *d)
> if (bank->eint_type != EINT_TYPE_WKUP)
> continue;
>
> + /* Set Digital Filter */
> + if (bank->fltcon_type != FLT_DEFAULT)
> + exynos_eint_flt_config(d, bank, EXYNOS9_FLTCON_SEL_DIGITAL);
> +
> bank->irq_chip = devm_kmemdup(dev, irq_chip, sizeof(*irq_chip),
> GFP_KERNEL);
> if (!bank->irq_chip) {
> @@ -658,6 +727,7 @@ static void exynos_pinctrl_suspend_bank(
> void exynos_pinctrl_suspend(struct samsung_pinctrl_drv_data *drvdata)
> {
> struct samsung_pin_bank *bank = drvdata->pin_banks;
> + struct samsung_pinctrl_drv_data *d = bank->drvdata;
> struct exynos_irq_chip *irq_chip = NULL;
> int i;
>
> @@ -665,6 +735,9 @@ void exynos_pinctrl_suspend(struct samsung_pinctrl_drv_data *drvdata)
> if (bank->eint_type == EINT_TYPE_GPIO)
> exynos_pinctrl_suspend_bank(drvdata, bank);
> else if (bank->eint_type == EINT_TYPE_WKUP) {
> + /* Setting Delay (Analog) Filter */
> + if (bank->fltcon_type != FLT_DEFAULT)
> + exynos_eint_flt_config(d, bank, EXYNOS9_FLTCON_SEL_DELAY);
> if (!irq_chip) {
> irq_chip = bank->irq_chip;
> irq_chip->set_eint_wakeup_mask(drvdata,
> @@ -707,11 +780,18 @@ static void exynos_pinctrl_resume_bank(
> void exynos_pinctrl_resume(struct samsung_pinctrl_drv_data *drvdata)
> {
> struct samsung_pin_bank *bank = drvdata->pin_banks;
> + struct samsung_pinctrl_drv_data *d = bank->drvdata;
> int i;
>
> for (i = 0; i < drvdata->nr_banks; ++i, ++bank)
> - if (bank->eint_type == EINT_TYPE_GPIO)
> + if (bank->eint_type == EINT_TYPE_GPIO) {
> exynos_pinctrl_resume_bank(drvdata, bank);
> + } else if (bank->eint_type == EINT_TYPE_WKUP ||
> + bank->eint_type == EINT_TYPE_WKUP_MUX) {
> + /* Set Digital Filter */
> + if (bank->fltcon_type != FLT_DEFAULT)
> + exynos_eint_flt_config(d, bank, EXYNOS9_FLTCON_SEL_DIGITAL);
> + }
> }
>
> static void exynos_retention_enable(struct samsung_pinctrl_drv_data *drvdata)
> diff --git a/drivers/pinctrl/samsung/pinctrl-exynos.h b/drivers/pinctrl/samsung/pinctrl-exynos.h
> index 7bd6d82c9f36..63b2426ad5d6 100644
> --- a/drivers/pinctrl/samsung/pinctrl-exynos.h
> +++ b/drivers/pinctrl/samsung/pinctrl-exynos.h
> @@ -50,6 +50,13 @@
>
> #define EXYNOS_EINT_MAX_PER_BANK 8
> #define EXYNOS_EINT_NR_WKUP_EINT
> +/* EINT filter configuration */
> +#define EXYNOS9_FLTCON_EN BIT(7)
> +#define EXYNOS9_FLTCON_SEL_DIGITAL BIT(6)
> +#define EXYNOS9_FLTCON_SEL_DELAY 0
> +#define EXYNOS9_FLTCON_MASK 0xff
> +#define EXYNOS9_FLTCON_LEN 8
> +#define EXYNOS9_FLTCON_NR_PIN 4
>
> #define EXYNOS_PIN_BANK_EINTN(pins, reg, id) \
> { \
> diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.c b/drivers/pinctrl/samsung/pinctrl-samsung.c
> index e54847040b4a..449f8109d8b5 100644
> --- a/drivers/pinctrl/samsung/pinctrl-samsung.c
> +++ b/drivers/pinctrl/samsung/pinctrl-samsung.c
> @@ -1104,6 +1104,8 @@ samsung_pinctrl_get_soc_data(struct samsung_pinctrl_drv_data *d,
> bank->eint_func = bdata->eint_func;
> bank->eint_type = bdata->eint_type;
> bank->eint_mask = bdata->eint_mask;
> + bank->fltcon_type = bdata->fltcon_type;
> + bank->fltcon_offset = bdata->fltcon_offset;
> bank->eint_offset = bdata->eint_offset;
> bank->name = bdata->name;
>
> diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.h b/drivers/pinctrl/samsung/pinctrl-samsung.h
> index 9af93e3d8d9f..de2ca8e8b378 100644
> --- a/drivers/pinctrl/samsung/pinctrl-samsung.h
> +++ b/drivers/pinctrl/samsung/pinctrl-samsung.h
> @@ -82,6 +82,21 @@ enum eint_type {
> EINT_TYPE_WKUP_MUX,
> };
>
> +/**
> + * enum fltcon_type - filter selection
> + * @FLT_DEFAULT: filter not selectable, default digital filter
> + * @FLT_SELECT: filter selectable (digital or delay)
> + *
> + * Some banks on some SoCs (gs101 and possibly others) have a selectable
> + * filter on alive banks of 'delay/analog' or 'digital'. If the filter
> + * selection is not available then the default filter is used (digital).
> + */
> +
> +enum fltcon_type {
> + FLT_DEFAULT,
> + FLT_SELECTABLE,
> +};
> +
> /* maximum length of a pin in pin descriptor (example: "gpa0-0") */
> #define PIN_NAME_LENGTH 10
>
> @@ -122,6 +137,8 @@ struct samsung_pin_bank_type {
> * @eint_type: type of the external interrupt supported by the bank.
> * @eint_mask: bit mask of pins which support EINT function.
> * @eint_offset: SoC-specific EINT register or interrupt offset of bank.
> + * @fltcon_type: whether the filter (delay/digital) is selectable
> + * @fltcon_offset: SoC-specific EINT filter control register offset of bank.
> * @name: name to be prefixed for each pin in this pin bank.
> */
> struct samsung_pin_bank_data {
> @@ -133,6 +150,8 @@ struct samsung_pin_bank_data {
> enum eint_type eint_type;
> u32 eint_mask;
> u32 eint_offset;
> + enum fltcon_type fltcon_type;
> + u32 fltcon_offset;
> const char *name;
> };
>
> @@ -147,6 +166,8 @@ struct samsung_pin_bank_data {
> * @eint_type: type of the external interrupt supported by the bank.
> * @eint_mask: bit mask of pins which support EINT function.
> * @eint_offset: SoC-specific EINT register or interrupt offset of bank.
> + * @fltcon_type: whether the filter (delay/digital) is selectable
> + * @fltcon_offset: SoC-specific EINT filter control register offset of bank.
> * @name: name to be prefixed for each pin in this pin bank.
> * @pin_base: starting pin number of the bank.
> * @soc_priv: per-bank private data for SoC-specific code.
> @@ -169,6 +190,8 @@ struct samsung_pin_bank {
> enum eint_type eint_type;
> u32 eint_mask;
> u32 eint_offset;
> + enum fltcon_type fltcon_type;
> + u32 fltcon_offset;
> const char *name;
>
> u32 pin_base;
> --
> 2.42.0.655.g421f12c284-goog
>
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