drivers: pinctrl: Add pinctrl driver for Microchip PIC32.

In PIC32 pin-controller is a combined gpio-controller, pin-mux and
pin-config module. Remappable peripherals are assigned pins through
per-pin based muxing logic. And pin configuration are performed on
specific port registers which are shared along with gpio controller.
Note, non-remappable peripherals have default pins assigned thus
require no muxing.

Signed-off-by: Purna Chandra Mandal <purna.mandal@microchip.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

3 files changed, 374 insertions, 0 deletions

diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 57e6142..5dd2ddd 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -131,6 +131,16 @@ config PINCTRL_SANDBOX
 	  actually does nothing but print debug messages when pinctrl
 	  operations are invoked.
 
+config PIC32_PINCTRL
+	bool "Microchip PIC32 pin-control and pin-mux driver"
+	depends on DM && MACH_PIC32
+	default y
+	help
+	  Supports individual pin selection and configuration for each remappable
+	  peripheral available on Microchip PIC32 SoCs. This driver is controlled
+	  by a device tree node which contains both GPIO defintion and pin control
+	  functions.
+
 endif
 
 source "drivers/pinctrl/uniphier/Kconfig"
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index 70d25dc..b4f4650 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip/
 obj-$(CONFIG_PINCTRL_SANDBOX)	+= pinctrl-sandbox.o
 
 obj-$(CONFIG_ARCH_UNIPHIER)	+= uniphier/
+obj-$(CONFIG_PIC32_PINCTRL)	+= pinctrl_pic32.o
diff --git a/drivers/pinctrl/pinctrl_pic32.c b/drivers/pinctrl/pinctrl_pic32.c
new file mode 100644
index 0000000..5cf97ec
--- /dev/null
+++ b/drivers/pinctrl/pinctrl_pic32.c
@@ -0,0 +1,363 @@
+/*
+ * Pinctrl driver for Microchip PIC32 SoCs
+ * Copyright (c) 2015 Microchip Technology Inc.
+ * Written by Purna Chandra Mandal <purna.mandal@microchip.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <dm/pinctrl.h>
+#include <dm/root.h>
+#include <mach/pic32.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* PIC32 has 10 peripheral ports with 16 pins each.
+ * Ports are marked PORTA-PORTK or PORT0-PORT9.
+ */
+enum {
+	PIC32_PORT_A = 0,
+	PIC32_PORT_B = 1,
+	PIC32_PORT_C = 2,
+	PIC32_PORT_D = 3,
+	PIC32_PORT_E = 4,
+	PIC32_PORT_F = 5,
+	PIC32_PORT_G = 6,
+	PIC32_PORT_H = 7,
+	PIC32_PORT_J = 8, /* no PORT_I */
+	PIC32_PORT_K = 9,
+	PIC32_PINS_PER_PORT = 16,
+};
+
+#define PIN_CONFIG_PIC32_DIGITAL	(PIN_CONFIG_END + 1)
+#define PIN_CONFIG_PIC32_ANALOG		(PIN_CONFIG_END + 2)
+
+/* pin configuration descriptor */
+struct pic32_pin_config {
+	u16 port;	/* port number */
+	u16 pin;	/* pin number in the port */
+	u32 config;	/* one of PIN_CONFIG_* */
+};
+#define PIN_CONFIG(_prt, _pin, _cfg) \
+	{.port = (_prt), .pin = (_pin), .config = (_cfg), }
+
+/* In PIC32 muxing is performed at pin-level through two
+ * different set of registers - one set for input functions,
+ * and other for output functions.
+ * Pin configuration is handled through port register.
+ */
+/* Port control registers */
+struct pic32_reg_port {
+	struct pic32_reg_atomic ansel;
+	struct pic32_reg_atomic tris;
+	struct pic32_reg_atomic port;
+	struct pic32_reg_atomic lat;
+	struct pic32_reg_atomic odc;
+	struct pic32_reg_atomic cnpu;
+	struct pic32_reg_atomic cnpd;
+	struct pic32_reg_atomic cncon;
+	struct pic32_reg_atomic unused[8];
+};
+
+/* Input function mux registers */
+struct pic32_reg_in_mux {
+	u32 unused0;
+	u32 int1[4];
+	u32 unused1;
+	u32 t2ck[8];
+	u32 ic1[9];
+	u32 unused2;
+	u32 ocfar;
+	u32 unused3;
+	u32 u1rx;
+	u32 u1cts;
+	u32 u2rx;
+	u32 u2cts;
+	u32 u3rx;
+	u32 u3cts;
+	u32 u4rx;
+	u32 u4cts;
+	u32 u5rx;
+	u32 u5cts;
+	u32 u6rx;
+	u32 u6cts;
+	u32 unused4;
+	u32 sdi1;
+	u32 ss1;
+	u32 unused5;
+	u32 sdi2;
+	u32 ss2;
+	u32 unused6;
+	u32 sdi3;
+	u32 ss3;
+	u32 unused7;
+	u32 sdi4;
+	u32 ss4;
+	u32 unused8;
+	u32 sdi5;
+	u32 ss5;
+	u32 unused9;
+	u32 sdi6;
+	u32 ss6;
+	u32 c1rx;
+	u32 c2rx;
+	u32 refclki1;
+	u32 refclki2;
+	u32 refclki3;
+	u32 refclki4;
+};
+
+/* output mux register offset */
+#define PPS_OUT(__port, __pin) \
+	(((__port) * PIC32_PINS_PER_PORT + (__pin)) << 2)
+
+
+struct pic32_pinctrl_priv {
+	struct pic32_reg_in_mux *mux_in; /* mux input function */
+	struct pic32_reg_port *pinconf; /* pin configuration*/
+	void __iomem *mux_out;	/* mux output function */
+};
+
+enum {
+	PERIPH_ID_UART1,
+	PERIPH_ID_UART2,
+	PERIPH_ID_ETH,
+	PERIPH_ID_USB,
+	PERIPH_ID_SDHCI,
+	PERIPH_ID_I2C1,
+	PERIPH_ID_I2C2,
+	PERIPH_ID_SPI1,
+	PERIPH_ID_SPI2,
+	PERIPH_ID_SQI,
+};
+
+static int pic32_pinconfig_one(struct pic32_pinctrl_priv *priv,
+			       u32 port_nr, u32 pin, u32 param)
+{
+	struct pic32_reg_port *port;
+
+	port = &priv->pinconf[port_nr];
+	switch (param) {
+	case PIN_CONFIG_PIC32_DIGITAL:
+		writel(BIT(pin), &port->ansel.clr);
+		break;
+	case PIN_CONFIG_PIC32_ANALOG:
+		writel(BIT(pin), &port->ansel.set);
+		break;
+	case PIN_CONFIG_INPUT_ENABLE:
+		writel(BIT(pin), &port->tris.set);
+		break;
+	case PIN_CONFIG_OUTPUT:
+		writel(BIT(pin), &port->tris.clr);
+		break;
+	case PIN_CONFIG_BIAS_PULL_UP:
+		writel(BIT(pin), &port->cnpu.set);
+		break;
+	case PIN_CONFIG_BIAS_PULL_DOWN:
+		writel(BIT(pin), &port->cnpd.set);
+		break;
+	case PIN_CONFIG_DRIVE_OPEN_DRAIN:
+		writel(BIT(pin), &port->odc.set);
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static int pic32_pinconfig_set(struct pic32_pinctrl_priv *priv,
+			       const struct pic32_pin_config *list, int count)
+{
+	int i;
+
+	for (i = 0 ; i < count; i++)
+		pic32_pinconfig_one(priv, list[i].port,
+				    list[i].pin, list[i].config);
+
+	return 0;
+}
+
+static void pic32_eth_pin_config(struct udevice *dev)
+{
+	struct pic32_pinctrl_priv *priv = dev_get_priv(dev);
+	const struct pic32_pin_config configs[] = {
+		/* EMDC - D11 */
+		PIN_CONFIG(PIC32_PORT_D, 11, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_D, 11, PIN_CONFIG_OUTPUT),
+		/* ETXEN */
+		PIN_CONFIG(PIC32_PORT_D, 6, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_D, 6, PIN_CONFIG_OUTPUT),
+		/* ECRSDV */
+		PIN_CONFIG(PIC32_PORT_H, 13, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_H, 13, PIN_CONFIG_INPUT_ENABLE),
+		/* ERXD0 */
+		PIN_CONFIG(PIC32_PORT_H, 8, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_H, 8, PIN_CONFIG_INPUT_ENABLE),
+		PIN_CONFIG(PIC32_PORT_H, 8, PIN_CONFIG_BIAS_PULL_DOWN),
+		/* ERXD1 */
+		PIN_CONFIG(PIC32_PORT_H, 5, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_H, 5, PIN_CONFIG_INPUT_ENABLE),
+		PIN_CONFIG(PIC32_PORT_H, 5, PIN_CONFIG_BIAS_PULL_DOWN),
+		/* EREFCLK */
+		PIN_CONFIG(PIC32_PORT_J, 11, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_J, 11, PIN_CONFIG_INPUT_ENABLE),
+		/* ETXD1 */
+		PIN_CONFIG(PIC32_PORT_J, 9, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_J, 9, PIN_CONFIG_OUTPUT),
+		/* ETXD0 */
+		PIN_CONFIG(PIC32_PORT_J, 8, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_J, 8, PIN_CONFIG_OUTPUT),
+		/* EMDIO */
+		PIN_CONFIG(PIC32_PORT_J, 1, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_J, 1, PIN_CONFIG_INPUT_ENABLE),
+		/* ERXERR */
+		PIN_CONFIG(PIC32_PORT_F, 3, PIN_CONFIG_PIC32_DIGITAL),
+		PIN_CONFIG(PIC32_PORT_F, 3, PIN_CONFIG_INPUT_ENABLE),
+	};
+
+	pic32_pinconfig_set(priv, configs, ARRAY_SIZE(configs));
+}
+
+static int pic32_pinctrl_request(struct udevice *dev, int func, int flags)
+{
+	struct pic32_pinctrl_priv *priv = dev_get_priv(dev);
+
+	switch (func) {
+	case PERIPH_ID_UART2:
+		/* PPS for U2 RX/TX */
+		writel(0x02, priv->mux_out + PPS_OUT(PIC32_PORT_G, 9));
+		writel(0x05, &priv->mux_in->u2rx); /* B0 */
+		/* set digital mode */
+		pic32_pinconfig_one(priv, PIC32_PORT_G, 9,
+				    PIN_CONFIG_PIC32_DIGITAL);
+		pic32_pinconfig_one(priv, PIC32_PORT_B, 0,
+				    PIN_CONFIG_PIC32_DIGITAL);
+		break;
+	case PERIPH_ID_ETH:
+		pic32_eth_pin_config(dev);
+		break;
+	default:
+		debug("%s: unknown-unhandled case\n", __func__);
+		break;
+	}
+
+	return 0;
+}
+
+static int pic32_pinctrl_get_periph_id(struct udevice *dev,
+				       struct udevice *periph)
+{
+	int ret;
+	u32 cell[2];
+
+	ret = fdtdec_get_int_array(gd->fdt_blob, periph->of_offset,
+				   "interrupts", cell, ARRAY_SIZE(cell));
+	if (ret < 0)
+		return -EINVAL;
+
+	/* interrupt number */
+	switch (cell[0]) {
+	case 112 ... 114:
+		return PERIPH_ID_UART1;
+	case 145 ... 147:
+		return PERIPH_ID_UART2;
+	case 109 ... 111:
+		return PERIPH_ID_SPI1;
+	case 142 ... 144:
+		return PERIPH_ID_SPI2;
+	case 115 ... 117:
+		return PERIPH_ID_I2C1;
+	case 148 ... 150:
+		return PERIPH_ID_I2C2;
+	case 132 ... 133:
+		return PERIPH_ID_USB;
+	case 169:
+		return PERIPH_ID_SQI;
+	case 191:
+		return PERIPH_ID_SDHCI;
+	case 153:
+		return PERIPH_ID_ETH;
+	default:
+		break;
+	}
+
+	return -ENOENT;
+}
+
+static int pic32_pinctrl_set_state_simple(struct udevice *dev,
+					  struct udevice *periph)
+{
+	int func;
+
+	debug("%s: periph %s\n", __func__, periph->name);
+	func = pic32_pinctrl_get_periph_id(dev, periph);
+	if (func < 0)
+		return func;
+	return pic32_pinctrl_request(dev, func, 0);
+}
+
+static struct pinctrl_ops pic32_pinctrl_ops = {
+	.set_state_simple	= pic32_pinctrl_set_state_simple,
+	.request		= pic32_pinctrl_request,
+	.get_periph_id		= pic32_pinctrl_get_periph_id,
+};
+
+static int pic32_pinctrl_probe(struct udevice *dev)
+{
+	struct pic32_pinctrl_priv *priv = dev_get_priv(dev);
+	struct fdt_resource res;
+	void *fdt = (void *)gd->fdt_blob;
+	int node = dev->of_offset;
+	int ret;
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "ppsin", &res);
+	if (ret < 0) {
+		printf("pinctrl: resource \"ppsin\" not found\n");
+		return ret;
+	}
+	priv->mux_in = ioremap(res.start, fdt_resource_size(&res));
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "ppsout", &res);
+	if (ret < 0) {
+		printf("pinctrl: resource \"ppsout\" not found\n");
+		return ret;
+	}
+	priv->mux_out = ioremap(res.start, fdt_resource_size(&res));
+
+	ret = fdt_get_named_resource(fdt, node, "reg", "reg-names",
+				     "port", &res);
+	if (ret < 0) {
+		printf("pinctrl: resource \"port\" not found\n");
+		return ret;
+	}
+	priv->pinconf = ioremap(res.start, fdt_resource_size(&res));
+
+	return 0;
+}
+
+static int pic32_pinctrl_bind(struct udevice *dev)
+{
+	/* scan child GPIO banks */
+	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
+}
+
+static const struct udevice_id pic32_pinctrl_ids[] = {
+	{ .compatible = "microchip,pic32mzda-pinctrl" },
+	{ }
+};
+
+U_BOOT_DRIVER(pinctrl_pic32) = {
+	.name		= "pinctrl_pic32",
+	.id		= UCLASS_PINCTRL,
+	.of_match	= pic32_pinctrl_ids,
+	.ops		= &pic32_pinctrl_ops,
+	.probe		= pic32_pinctrl_probe,
+	.bind		= pic32_pinctrl_bind,
+	.priv_auto_alloc_size = sizeof(struct pic32_pinctrl_priv),
+};