test: pinmux: Add test for pin muxing

This extends the pinctrl-sandbox driver to support pin muxing, and adds a
test for that behaviour. The test is done in C and not python (like the
existing tests for the pinctrl uclass) because it needs to call
pinctrl_select_state.  Another option could be to add a command that
invokes pinctrl_select_state and then test everything in
test/py/tests/test_pinmux.py.

The pinctrl-sandbox driver now mimics the way that many pinmux devices
work.  There are two groups of pins which are muxed together, as well as
four pins which are muxed individually. I have tried to test all normal
paths. However, very few error cases are explicitly checked for.

Signed-off-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

1 files changed, 138 insertions, 48 deletions

diff --git a/drivers/pinctrl/pinctrl-sandbox.c b/drivers/pinctrl/pinctrl-sandbox.c
index ac0119d198..d27f74248d 100644
--- a/drivers/pinctrl/pinctrl-sandbox.c
+++ b/drivers/pinctrl/pinctrl-sandbox.c
@@ -1,57 +1,70 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * Copyright (C) 2015  Masahiro Yamada <yamada.masahiro@socionext.com>
+ * Copyright (C) 2020 Sean Anderson <seanga2@gmail.com>
+ * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
  */
 
-/* #define DEBUG */
-
 #include <common.h>
 #include <dm.h>
-#include <log.h>
 #include <dm/pinctrl.h>
+#include <dt-bindings/pinctrl/sandbox-pinmux.h>
+#include <log.h>
 #include <linux/bitops.h>
 
+/*
+ * This driver emulates a pin controller with the following rules:
+ * - The pinctrl config for each pin must be set individually
+ * - The first three pins (P0-P2) must be muxed as a group
+ * - The next two pins (P3-P4) must be muxed as a group
+ * - The last four pins (P5-P8) must be muxed individually
+ */
+
 static const char * const sandbox_pins[] = {
-	"SCL",
-	"SDA",
-	"TX",
-	"RX",
-	"W1",
-	"GPIO0",
-	"GPIO1",
-	"GPIO2",
-	"GPIO3",
+#define PIN(x) \
+	[x] = "P" #x
+	PIN(0),
+	PIN(1),
+	PIN(2),
+	PIN(3),
+	PIN(4),
+	PIN(5),
+	PIN(6),
+	PIN(7),
+	PIN(8),
+#undef PIN
 };
 
-static const char * const sandbox_pins_muxing[] = {
-	"I2C SCL",
-	"I2C SDA",
-	"Uart TX",
-	"Uart RX",
-	"1-wire gpio",
-	"gpio",
-	"gpio",
-	"gpio",
-	"gpio",
+static const char * const sandbox_pins_muxing[][2] = {
+	{ "UART TX", "I2C SCL" },
+	{ "UART RX", "I2C SDA" },
+	{ "SPI SCLK", "I2S SCK" },
+	{ "SPI MOSI", "I2S SD" },
+	{ "SPI MISO", "I2S WS" },
+	{ "GPIO0", "SPI CS0" },
+	{ "GPIO1", "SPI CS1" },
+	{ "GPIO2", "PWM0" },
+	{ "GPIO3", "PWM1" },
 };
 
+#define SANDBOX_GROUP_I2C_UART 0
+#define SANDBOX_GROUP_SPI_I2S 1
+
 static const char * const sandbox_groups[] = {
-	"i2c",
-	"serial_a",
-	"serial_b",
-	"spi",
-	"w1",
+	[SANDBOX_GROUP_I2C_UART] = "I2C_UART",
+	[SANDBOX_GROUP_SPI_I2S] = "SPI_I2S",
 };
 
 static const char * const sandbox_functions[] = {
-	"i2c",
-	"serial",
-	"spi",
-	"w1",
-	"gpio",
-	"gpio",
-	"gpio",
-	"gpio",
+#define FUNC(id) \
+	[SANDBOX_PINMUX_##id] = #id
+	FUNC(UART),
+	FUNC(I2C),
+	FUNC(SPI),
+	FUNC(I2S),
+	FUNC(GPIO),
+	FUNC(CS),
+	FUNC(PWM),
+#undef FUNC
 };
 
 static const struct pinconf_param sandbox_conf_params[] = {
@@ -68,9 +81,12 @@ static const struct pinconf_param sandbox_conf_params[] = {
 	{ "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 },
 };
 
-/* bitfield used to save param and value of each pin/selector */
-static unsigned int sandbox_pins_param[ARRAY_SIZE(sandbox_pins)];
-static unsigned int sandbox_pins_value[ARRAY_SIZE(sandbox_pins)];
+/* Bitfield used to save param and value of each pin/selector */
+struct sandbox_pinctrl_priv {
+	unsigned int mux;
+	unsigned int pins_param[ARRAY_SIZE(sandbox_pins)];
+	unsigned int pins_value[ARRAY_SIZE(sandbox_pins)];
+};
 
 static int sandbox_get_pins_count(struct udevice *dev)
 {
@@ -87,16 +103,18 @@ static int sandbox_get_pin_muxing(struct udevice *dev,
 				  char *buf, int size)
 {
 	const struct pinconf_param *p;
+	struct sandbox_pinctrl_priv *priv = dev_get_priv(dev);
 	int i;
 
-	snprintf(buf, size, "%s", sandbox_pins_muxing[selector]);
+	snprintf(buf, size, "%s",
+		 sandbox_pins_muxing[selector][!!(priv->mux & BIT(selector))]);
 
-	if (sandbox_pins_param[selector]) {
+	if (priv->pins_param[selector]) {
 		for (i = 0, p = sandbox_conf_params;
 		     i < ARRAY_SIZE(sandbox_conf_params);
 		     i++, p++) {
-			if ((sandbox_pins_param[selector] & BIT(p->param)) &&
-			    (!!(sandbox_pins_value[selector] & BIT(p->param)) ==
+			if ((priv->pins_param[selector] & BIT(p->param)) &&
+			    (!!(priv->pins_value[selector] & BIT(p->param)) ==
 			     p->default_value)) {
 				strncat(buf, " ", size);
 				strncat(buf, p->property, size);
@@ -133,12 +151,32 @@ static const char *sandbox_get_function_name(struct udevice *dev,
 static int sandbox_pinmux_set(struct udevice *dev, unsigned pin_selector,
 			      unsigned func_selector)
 {
+	int mux;
+	struct sandbox_pinctrl_priv *priv = dev_get_priv(dev);
+
 	debug("sandbox pinmux: pin = %d (%s), function = %d (%s)\n",
 	      pin_selector, sandbox_get_pin_name(dev, pin_selector),
 	      func_selector, sandbox_get_function_name(dev, func_selector));
 
-	sandbox_pins_param[pin_selector] = 0;
-	sandbox_pins_value[pin_selector] = 0;
+	if (pin_selector < 5)
+		return -EINVAL;
+
+	switch (func_selector) {
+	case SANDBOX_PINMUX_GPIO:
+		mux = 0;
+		break;
+	case SANDBOX_PINMUX_CS:
+	case SANDBOX_PINMUX_PWM:
+		mux = BIT(pin_selector);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	priv->mux &= ~BIT(pin_selector);
+	priv->mux |= mux;
+	priv->pins_param[pin_selector] = 0;
+	priv->pins_value[pin_selector] = 0;
 
 	return 0;
 }
@@ -147,25 +185,75 @@ static int sandbox_pinmux_group_set(struct udevice *dev,
 				    unsigned group_selector,
 				    unsigned func_selector)
 {
+	bool mux;
+	int i, group_start, group_end;
+	struct sandbox_pinctrl_priv *priv = dev_get_priv(dev);
+	unsigned int mask;
+
 	debug("sandbox pinmux: group = %d (%s), function = %d (%s)\n",
 	      group_selector, sandbox_get_group_name(dev, group_selector),
 	      func_selector, sandbox_get_function_name(dev, func_selector));
 
+	if (group_selector == SANDBOX_GROUP_I2C_UART) {
+		group_start = 0;
+		group_end = 1;
+
+		if (func_selector == SANDBOX_PINMUX_UART)
+			mux = false;
+		else if (func_selector == SANDBOX_PINMUX_I2C)
+			mux = true;
+		else
+			return -EINVAL;
+	} else if (group_selector == SANDBOX_GROUP_SPI_I2S) {
+		group_start = 2;
+		group_end = 4;
+
+		if (func_selector == SANDBOX_PINMUX_SPI)
+			mux = false;
+		else if (func_selector == SANDBOX_PINMUX_I2S)
+			mux = true;
+		else
+			return -EINVAL;
+	} else {
+		return -EINVAL;
+	}
+
+	mask = GENMASK(group_end, group_start);
+	priv->mux &= ~mask;
+	priv->mux |= mux ? mask : 0;
+
+	for (i = group_start; i < group_end; i++) {
+		priv->pins_param[i] = 0;
+		priv->pins_value[i] = 0;
+	}
+
 	return 0;
 }
 
+static int sandbox_pinmux_property_set(struct udevice *dev, u32 pinmux_group)
+{
+	int ret;
+	unsigned pin_selector = pinmux_group & 0xFFFF;
+	unsigned func_selector = pinmux_group >> 16;
+
+	ret = sandbox_pinmux_set(dev, pin_selector, func_selector);
+	return ret ? ret : pin_selector;
+}
+
 static int sandbox_pinconf_set(struct udevice *dev, unsigned pin_selector,
 			       unsigned param, unsigned argument)
 {
+	struct sandbox_pinctrl_priv *priv = dev_get_priv(dev);
+
 	debug("sandbox pinconf: pin = %d (%s), param = %d, arg = %d\n",
 	      pin_selector, sandbox_get_pin_name(dev, pin_selector),
 	      param, argument);
 
-	sandbox_pins_param[pin_selector] |= BIT(param);
+	priv->pins_param[pin_selector] |= BIT(param);
 	if (argument)
-		sandbox_pins_value[pin_selector] |= BIT(param);
+		priv->pins_value[pin_selector] |= BIT(param);
 	else
-		sandbox_pins_value[pin_selector] &= ~BIT(param);
+		priv->pins_value[pin_selector] &= ~BIT(param);
 
 	return 0;
 }
@@ -191,6 +279,7 @@ const struct pinctrl_ops sandbox_pinctrl_ops = {
 	.get_function_name = sandbox_get_function_name,
 	.pinmux_set = sandbox_pinmux_set,
 	.pinmux_group_set = sandbox_pinmux_group_set,
+	.pinmux_property_set = sandbox_pinmux_property_set,
 	.pinconf_num_params = ARRAY_SIZE(sandbox_conf_params),
 	.pinconf_params = sandbox_conf_params,
 	.pinconf_set = sandbox_pinconf_set,
@@ -207,5 +296,6 @@ U_BOOT_DRIVER(sandbox_pinctrl) = {
 	.name = "sandbox_pinctrl",
 	.id = UCLASS_PINCTRL,
 	.of_match = sandbox_pinctrl_match,
+	.priv_auto_alloc_size = sizeof(struct sandbox_pinctrl_priv),
 	.ops = &sandbox_pinctrl_ops,
 };