pinctrl: at91: add pinctrl driver
AT91 PIO controller is a combined gpio-controller, pin-mux and
pin-config module. The peripheral's pins are assigned through
per-pin based muxing logic.
Each SoC will have to describe the its limitation and pin
configuration via device tree. This will allow to do not need
to touch the C code when adding new SoC if the IP version is
supported.
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/pinctrl/pinctrl-at91.c b/drivers/pinctrl/pinctrl-at91.c
new file mode 100644
index 0000000..904e1bd
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-at91.c
@@ -0,0 +1,453 @@
+/*
+ * Atmel PIO pinctrl driver
+ *
+ * Copyright (C) 2016 Atmel Corporation
+ * Wenyou.Yang <wenyou.yang@atmel.com>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm/device.h>
+#include <dm/pinctrl.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <mach/at91_pio.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define MAX_GPIO_BANKS 5
+#define MAX_NB_GPIO_PER_BANK 32
+
+#define MAX_PINMUX_ENTRIES 200
+
+struct at91_pinctrl_priv {
+ struct at91_port *reg_base[MAX_GPIO_BANKS];
+ u32 nbanks;
+};
+
+#define PULL_UP BIT(0)
+#define MULTI_DRIVE BIT(1)
+#define DEGLITCH BIT(2)
+#define PULL_DOWN BIT(3)
+#define DIS_SCHMIT BIT(4)
+#define DRIVE_STRENGTH_SHIFT 5
+#define DRIVE_STRENGTH_MASK 0x3
+#define DRIVE_STRENGTH (DRIVE_STRENGTH_MASK << DRIVE_STRENGTH_SHIFT)
+#define OUTPUT BIT(7)
+#define OUTPUT_VAL_SHIFT 8
+#define OUTPUT_VAL (0x1 << OUTPUT_VAL_SHIFT)
+#define DEBOUNCE BIT(16)
+#define DEBOUNCE_VAL_SHIFT 17
+#define DEBOUNCE_VAL (0x3fff << DEBOUNCE_VAL_SHIFT)
+
+/**
+ * These defines will translated the dt binding settings to our internal
+ * settings. They are not necessarily the same value as the register setting.
+ * The actual drive strength current of low, medium and high must be looked up
+ * from the corresponding device datasheet. This value is different for pins
+ * that are even in the same banks. It is also dependent on VCC.
+ * DRIVE_STRENGTH_DEFAULT is just a placeholder to avoid changing the drive
+ * strength when there is no dt config for it.
+ */
+#define DRIVE_STRENGTH_DEFAULT (0 << DRIVE_STRENGTH_SHIFT)
+#define DRIVE_STRENGTH_LOW (1 << DRIVE_STRENGTH_SHIFT)
+#define DRIVE_STRENGTH_MED (2 << DRIVE_STRENGTH_SHIFT)
+#define DRIVE_STRENGTH_HI (3 << DRIVE_STRENGTH_SHIFT)
+
+enum at91_mux {
+ AT91_MUX_GPIO = 0,
+ AT91_MUX_PERIPH_A = 1,
+ AT91_MUX_PERIPH_B = 2,
+ AT91_MUX_PERIPH_C = 3,
+ AT91_MUX_PERIPH_D = 4,
+};
+
+/**
+ * struct at91_pinctrl_mux_ops - describes an AT91 mux ops group
+ * on new IP with support for periph C and D the way to mux in
+ * periph A and B has changed
+ * So provide the right callbacks
+ * if not present means the IP does not support it
+ * @mux_A_periph: assign the corresponding pin to the peripheral A function.
+ * @mux_B_periph: assign the corresponding pin to the peripheral B function.
+ * @mux_C_periph: assign the corresponding pin to the peripheral C function.
+ * @mux_D_periph: assign the corresponding pin to the peripheral D function.
+ * @set_deglitch: enable/disable the deglitch feature.
+ * @set_debounce: enable/disable the debounce feature.
+ * @set_pulldown: enable/disable the pulldown feature.
+ * @disable_schmitt_trig: disable schmitt trigger
+ */
+struct at91_pinctrl_mux_ops {
+ void (*mux_A_periph)(struct at91_port *pio, u32 mask);
+ void (*mux_B_periph)(struct at91_port *pio, u32 mask);
+ void (*mux_C_periph)(struct at91_port *pio, u32 mask);
+ void (*mux_D_periph)(struct at91_port *pio, u32 mask);
+ void (*set_deglitch)(struct at91_port *pio, u32 mask, bool is_on);
+ void (*set_debounce)(struct at91_port *pio, u32 mask, bool is_on,
+ u32 div);
+ void (*set_pulldown)(struct at91_port *pio, u32 mask, bool is_on);
+ void (*disable_schmitt_trig)(struct at91_port *pio, u32 mask);
+ void (*set_drivestrength)(struct at91_port *pio, u32 pin,
+ u32 strength);
+};
+
+static u32 two_bit_pin_value_shift_amount(u32 pin)
+{
+ /* return the shift value for a pin for "two bit" per pin registers,
+ * i.e. drive strength */
+ return 2 * ((pin >= MAX_NB_GPIO_PER_BANK/2)
+ ? pin - MAX_NB_GPIO_PER_BANK/2 : pin);
+}
+
+static void at91_mux_disable_interrupt(struct at91_port *pio, u32 mask)
+{
+ writel(mask, &pio->idr);
+}
+
+static void at91_mux_set_pullup(struct at91_port *pio, u32 mask, bool on)
+{
+ if (on)
+ writel(mask, &pio->mux.pio3.ppddr);
+
+ writel(mask, (on ? &pio->puer : &pio->pudr));
+}
+
+static void at91_mux_set_output(struct at91_port *pio, unsigned mask,
+ bool is_on, bool val)
+{
+ writel(mask, (val ? &pio->sodr : &pio->codr));
+ writel(mask, (is_on ? &pio->oer : &pio->odr));
+}
+
+static void at91_mux_set_multidrive(struct at91_port *pio, u32 mask, bool on)
+{
+ writel(mask, (on ? &pio->mder : &pio->mddr));
+}
+
+static void at91_mux_set_A_periph(struct at91_port *pio, u32 mask)
+{
+ writel(mask, &pio->mux.pio2.asr);
+}
+
+static void at91_mux_set_B_periph(struct at91_port *pio, u32 mask)
+{
+ writel(mask, &pio->mux.pio2.bsr);
+}
+
+static void at91_mux_pio3_set_A_periph(struct at91_port *pio, u32 mask)
+{
+ writel(readl(&pio->mux.pio3.abcdsr1) & ~mask, &pio->mux.pio3.abcdsr1);
+ writel(readl(&pio->mux.pio3.abcdsr2) & ~mask, &pio->mux.pio3.abcdsr2);
+}
+
+static void at91_mux_pio3_set_B_periph(struct at91_port *pio, u32 mask)
+{
+ writel(readl(&pio->mux.pio3.abcdsr1) | mask, &pio->mux.pio3.abcdsr1);
+ writel(readl(&pio->mux.pio3.abcdsr2) & ~mask, &pio->mux.pio3.abcdsr2);
+}
+
+static void at91_mux_pio3_set_C_periph(struct at91_port *pio, u32 mask)
+{
+ writel(readl(&pio->mux.pio3.abcdsr1) & ~mask, &pio->mux.pio3.abcdsr1);
+ writel(readl(&pio->mux.pio3.abcdsr2) | mask, &pio->mux.pio3.abcdsr2);
+}
+
+static void at91_mux_pio3_set_D_periph(struct at91_port *pio, u32 mask)
+{
+ writel(readl(&pio->mux.pio3.abcdsr1) | mask, &pio->mux.pio3.abcdsr1);
+ writel(readl(&pio->mux.pio3.abcdsr2) | mask, &pio->mux.pio3.abcdsr2);
+}
+
+static void at91_mux_set_deglitch(struct at91_port *pio, u32 mask, bool is_on)
+{
+ writel(mask, (is_on ? &pio->ifer : &pio->ifdr));
+}
+
+static void at91_mux_pio3_set_deglitch(struct at91_port *pio,
+ u32 mask, bool is_on)
+{
+ if (is_on)
+ writel(mask, &pio->mux.pio3.ifscdr);
+ at91_mux_set_deglitch(pio, mask, is_on);
+}
+
+static void at91_mux_pio3_set_debounce(struct at91_port *pio, u32 mask,
+ bool is_on, u32 div)
+{
+ if (is_on) {
+ writel(mask, &pio->mux.pio3.ifscer);
+ writel(div & PIO_SCDR_DIV, &pio->mux.pio3.scdr);
+ writel(mask, &pio->ifer);
+ } else {
+ writel(mask, &pio->mux.pio3.ifscdr);
+ }
+}
+
+static void at91_mux_pio3_set_pulldown(struct at91_port *pio,
+ u32 mask, bool is_on)
+{
+ if (is_on)
+ writel(mask, &pio->pudr);
+
+ writel(mask, (is_on ? &pio->mux.pio3.ppder : &pio->mux.pio3.ppddr));
+}
+
+static void at91_mux_pio3_disable_schmitt_trig(struct at91_port *pio,
+ u32 mask)
+{
+ writel(readl(&pio->schmitt) | mask, &pio->schmitt);
+}
+
+static void set_drive_strength(void *reg, u32 pin, u32 strength)
+{
+ u32 shift = two_bit_pin_value_shift_amount(pin);
+
+ clrsetbits_le32(reg, DRIVE_STRENGTH_MASK << shift, strength << shift);
+}
+
+static void at91_mux_sama5d3_set_drivestrength(struct at91_port *pio,
+ u32 pin, u32 setting)
+{
+ void *reg;
+
+ reg = &pio->driver12;
+ if (pin >= MAX_NB_GPIO_PER_BANK / 2)
+ reg = &pio->driver2;
+
+ /* do nothing if setting is zero */
+ if (!setting)
+ return;
+
+ /* strength is 1 to 1 with setting for SAMA5 */
+ set_drive_strength(reg, pin, setting);
+}
+
+static void at91_mux_sam9x5_set_drivestrength(struct at91_port *pio,
+ u32 pin, u32 setting)
+{
+ void *reg;
+
+ reg = &pio->driver1;
+ if (pin >= MAX_NB_GPIO_PER_BANK / 2)
+ reg = &pio->driver12;
+
+ /* do nothing if setting is zero */
+ if (!setting)
+ return;
+
+ /* strength is inverse on SAM9x5s with our defines
+ * 0 = hi, 1 = med, 2 = low, 3 = rsvd */
+ setting = DRIVE_STRENGTH_HI - setting;
+
+ set_drive_strength(reg, pin, setting);
+}
+
+static struct at91_pinctrl_mux_ops at91rm9200_ops = {
+ .mux_A_periph = at91_mux_set_A_periph,
+ .mux_B_periph = at91_mux_set_B_periph,
+ .set_deglitch = at91_mux_set_deglitch,
+};
+
+static struct at91_pinctrl_mux_ops at91sam9x5_ops = {
+ .mux_A_periph = at91_mux_pio3_set_A_periph,
+ .mux_B_periph = at91_mux_pio3_set_B_periph,
+ .mux_C_periph = at91_mux_pio3_set_C_periph,
+ .mux_D_periph = at91_mux_pio3_set_D_periph,
+ .set_deglitch = at91_mux_pio3_set_deglitch,
+ .set_debounce = at91_mux_pio3_set_debounce,
+ .set_pulldown = at91_mux_pio3_set_pulldown,
+ .disable_schmitt_trig = at91_mux_pio3_disable_schmitt_trig,
+ .set_drivestrength = at91_mux_sam9x5_set_drivestrength,
+};
+
+static struct at91_pinctrl_mux_ops sama5d3_ops = {
+ .mux_A_periph = at91_mux_pio3_set_A_periph,
+ .mux_B_periph = at91_mux_pio3_set_B_periph,
+ .mux_C_periph = at91_mux_pio3_set_C_periph,
+ .mux_D_periph = at91_mux_pio3_set_D_periph,
+ .set_deglitch = at91_mux_pio3_set_deglitch,
+ .set_debounce = at91_mux_pio3_set_debounce,
+ .set_pulldown = at91_mux_pio3_set_pulldown,
+ .disable_schmitt_trig = at91_mux_pio3_disable_schmitt_trig,
+ .set_drivestrength = at91_mux_sama5d3_set_drivestrength,
+};
+
+static void at91_mux_gpio_disable(struct at91_port *pio, u32 mask)
+{
+ writel(mask, &pio->pdr);
+}
+
+static void at91_mux_gpio_enable(struct at91_port *pio, u32 mask, bool input)
+{
+ writel(mask, &pio->per);
+ writel(mask, (input ? &pio->odr : &pio->oer));
+}
+
+static int at91_pmx_set(struct at91_pinctrl_mux_ops *ops,
+ struct at91_port *pio, u32 mask, enum at91_mux mux)
+{
+ at91_mux_disable_interrupt(pio, mask);
+ switch (mux) {
+ case AT91_MUX_GPIO:
+ at91_mux_gpio_enable(pio, mask, 1);
+ break;
+ case AT91_MUX_PERIPH_A:
+ ops->mux_A_periph(pio, mask);
+ break;
+ case AT91_MUX_PERIPH_B:
+ ops->mux_B_periph(pio, mask);
+ break;
+ case AT91_MUX_PERIPH_C:
+ if (!ops->mux_C_periph)
+ return -EINVAL;
+ ops->mux_C_periph(pio, mask);
+ break;
+ case AT91_MUX_PERIPH_D:
+ if (!ops->mux_D_periph)
+ return -EINVAL;
+ ops->mux_D_periph(pio, mask);
+ break;
+ }
+ if (mux)
+ at91_mux_gpio_disable(pio, mask);
+
+ return 0;
+}
+
+static int at91_pinconf_set(struct at91_pinctrl_mux_ops *ops,
+ struct at91_port *pio, u32 pin, u32 config)
+{
+ u32 mask = BIT(pin);
+
+ if ((config & PULL_UP) && (config & PULL_DOWN))
+ return -EINVAL;
+
+ at91_mux_set_output(pio, mask, config & OUTPUT,
+ (config & OUTPUT_VAL) >> OUTPUT_VAL_SHIFT);
+ at91_mux_set_pullup(pio, mask, config & PULL_UP);
+ at91_mux_set_multidrive(pio, mask, config & MULTI_DRIVE);
+ if (ops->set_deglitch)
+ ops->set_deglitch(pio, mask, config & DEGLITCH);
+ if (ops->set_debounce)
+ ops->set_debounce(pio, mask, config & DEBOUNCE,
+ (config & DEBOUNCE_VAL) >> DEBOUNCE_VAL_SHIFT);
+ if (ops->set_pulldown)
+ ops->set_pulldown(pio, mask, config & PULL_DOWN);
+ if (ops->disable_schmitt_trig && config & DIS_SCHMIT)
+ ops->disable_schmitt_trig(pio, mask);
+ if (ops->set_drivestrength)
+ ops->set_drivestrength(pio, pin,
+ (config & DRIVE_STRENGTH) >> DRIVE_STRENGTH_SHIFT);
+
+ return 0;
+}
+
+static int at91_pin_check_config(struct udevice *dev, u32 bank, u32 pin)
+{
+ struct at91_pinctrl_priv *priv = dev_get_priv(dev);
+
+ if (bank >= priv->nbanks) {
+ debug("pin conf bank %d >= nbanks %d\n", bank, priv->nbanks);
+ return -EINVAL;
+ }
+
+ if (pin >= MAX_NB_GPIO_PER_BANK) {
+ debug("pin conf pin %d >= %d\n", pin, MAX_NB_GPIO_PER_BANK);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int at91_pinctrl_set_state(struct udevice *dev, struct udevice *config)
+{
+ struct at91_pinctrl_priv *priv = dev_get_priv(dev);
+ const void *blob = gd->fdt_blob;
+ int node = config->of_offset;
+ u32 cells[MAX_PINMUX_ENTRIES];
+ const u32 *list = cells;
+ u32 bank, pin;
+ u32 conf, mask, count, i;
+ int size;
+ int ret;
+ enum at91_mux mux;
+ struct at91_port *pio;
+ struct at91_pinctrl_mux_ops *ops =
+ (struct at91_pinctrl_mux_ops *)dev_get_driver_data(dev);
+
+ /*
+ * the binding format is atmel,pins = <bank pin mux CONFIG ...>,
+ * do sanity check and calculate pins number
+ */
+ size = fdtdec_get_int_array_count(blob, node, "atmel,pins",
+ cells, ARRAY_SIZE(cells));
+
+ /* we do not check return since it's safe node passed down */
+ count = size >> 2;
+ if (!count)
+ return -EINVAL;
+
+ for (i = 0; i < count; i++) {
+ bank = *list++;
+ pin = *list++;
+ mux = *list++;
+ conf = *list++;
+
+ ret = at91_pin_check_config(dev, bank, pin);
+ if (ret)
+ return ret;
+
+ pio = priv->reg_base[bank];
+ mask = BIT(pin);
+
+ ret = at91_pmx_set(ops, pio, mask, mux);
+ if (ret)
+ return ret;
+
+ ret = at91_pinconf_set(ops, pio, pin, conf);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+const struct pinctrl_ops at91_pinctrl_ops = {
+ .set_state = at91_pinctrl_set_state,
+};
+
+static int at91_pinctrl_probe(struct udevice *dev)
+{
+ struct at91_pinctrl_priv *priv = dev_get_priv(dev);
+ fdt_addr_t addr_base;
+ int index;
+
+ for (index = 0; index < MAX_GPIO_BANKS; index++) {
+ addr_base = dev_get_addr_index(dev, index);
+ if (addr_base == FDT_ADDR_T_NONE)
+ break;
+
+ priv->reg_base[index] = (struct at91_port *)addr_base;
+ }
+
+ priv->nbanks = index;
+
+ return 0;
+}
+
+static const struct udevice_id at91_pinctrl_match[] = {
+ { .compatible = "atmel,sama5d3-pinctrl", .data = (ulong)&sama5d3_ops },
+ { .compatible = "atmel,at91sam9x5-pinctrl", .data = (ulong)&at91sam9x5_ops },
+ { .compatible = "atmel,at91rm9200-pinctrl", .data = (ulong)&at91rm9200_ops },
+ {}
+};
+
+U_BOOT_DRIVER(at91_pinctrl) = {
+ .name = "pinctrl_at91",
+ .id = UCLASS_PINCTRL,
+ .of_match = at91_pinctrl_match,
+ .probe = at91_pinctrl_probe,
+ .priv_auto_alloc_size = sizeof(struct at91_pinctrl_priv),
+ .ops = &at91_pinctrl_ops,
+};