spmi: Add sandbox test driver

This patch adds emulated spmi bus controller with part of
pm8916 pmic on it to sandbox and tests validating SPMI uclass.

Signed-off-by: Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/sandbox/dts/sandbox.dts b/arch/sandbox/dts/sandbox.dts
index e3f02bf..2ae4014 100644
--- a/arch/sandbox/dts/sandbox.dts
+++ b/arch/sandbox/dts/sandbox.dts
@@ -240,6 +240,26 @@
 		status = "disabled";
 	};
 
+	spmi: spmi@0 {
+		compatible = "sandbox,spmi";
+		#address-cells = <0x1>;
+		#size-cells = <0x1>;
+		pm8916@0 {
+			compatible = "qcom,spmi-pmic";
+			reg = <0x0 0x1>;
+			#address-cells = <0x1>;
+			#size-cells = <0x1>;
+
+			spmi_gpios: gpios@c000 {
+				compatible = "qcom,pm8916-gpio";
+				reg = <0xc000 0x400>;
+				gpio-controller;
+				gpio-count = <4>;
+				#gpio-cells = <2>;
+				gpio-bank-name="spmi";
+			};
+		};
+	};
 };
 
 #include "cros-ec-keyboard.dtsi"
diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 9b8d658..8930009 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -351,6 +351,26 @@
 		status = "disabled";
 	};
 
+	spmi: spmi@0 {
+		compatible = "sandbox,spmi";
+		#address-cells = <0x1>;
+		#size-cells = <0x1>;
+		pm8916@0 {
+			compatible = "qcom,spmi-pmic";
+			reg = <0x0 0x1>;
+			#address-cells = <0x1>;
+			#size-cells = <0x1>;
+
+			spmi_gpios: gpios@c000 {
+				compatible = "qcom,pm8916-gpio";
+				reg = <0xc000 0x400>;
+				gpio-controller;
+				gpio-count = <4>;
+				#gpio-cells = <2>;
+				gpio-bank-name="spmi";
+			};
+		};
+	};
 };
 
 #include "sandbox_pmic.dtsi"
diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig
index d69c9fc..bfc8b61 100644
--- a/configs/sandbox_defconfig
+++ b/configs/sandbox_defconfig
@@ -31,6 +31,7 @@
 CONFIG_BLK=y
 CONFIG_CLK=y
 CONFIG_SANDBOX_GPIO=y
+CONFIG_PM8916_GPIO=y
 CONFIG_SYS_I2C_SANDBOX=y
 CONFIG_CROS_EC_KEYB=y
 CONFIG_LED=y
@@ -59,6 +60,9 @@
 CONFIG_PINCTRL_SANDBOX=y
 CONFIG_DM_PMIC=y
 CONFIG_DM_PMIC_SANDBOX=y
+CONFIG_PMIC_PM8916=y
+CONFIG_SPMI=y
+CONFIG_SPMI_SANDBOX=y
 CONFIG_DM_REGULATOR=y
 CONFIG_DM_REGULATOR_SANDBOX=y
 CONFIG_RAM=y
diff --git a/doc/device-tree-bindings/spmi/spmi-sandbox.txt b/doc/device-tree-bindings/spmi/spmi-sandbox.txt
new file mode 100644
index 0000000..8569a1a
--- /dev/null
+++ b/doc/device-tree-bindings/spmi/spmi-sandbox.txt
@@ -0,0 +1,31 @@
+Sandbox SPMI emulated arbiter.
+
+This is bus driver for Sandbox. It includes part of emulated pm8916 pmic.
+
+Required properties:
+- compatible: "sandbox,spmi"
+- #address-cells: 0x1 - childs slave ID address
+- #size-cells: 0x1
+
+Example:
+
+spmi: spmi@0 {
+	compatible = "sandbox,spmi";
+	#address-cells = <0x1>;
+	#size-cells = <0x1>;
+	pm8916@0 {
+		compatible = "qcom,spmi-pmic";
+		reg = <0x0 0x1>;
+		#address-cells = <0x1>;
+		#size-cells = <0x1>;
+
+		spmi_gpios: gpios@c000 {
+			compatible = "qcom,pm8916-gpio";
+			reg = <0xc000 0x400>;
+			gpio-controller;
+			gpio-count = <4>;
+			#gpio-cells = <2>;
+			gpio-bank-name="spmi";
+		};
+	};
+};
diff --git a/drivers/spmi/Kconfig b/drivers/spmi/Kconfig
index 0b9bd31..c70d675 100644
--- a/drivers/spmi/Kconfig
+++ b/drivers/spmi/Kconfig
@@ -7,4 +7,12 @@
 	  Select this to enable to support SPMI bus.
 	  SPMI (System Power Management Interface) bus is used
 	  to connect PMIC devices on various SoCs.
+
+config SPMI_SANDBOX
+	boolean "Support for Sandbox SPMI bus"
+	depends on SPMI
+	---help---
+	  Demo SPMI bus implementation. Emulates part of PM8916 as single
+          slave (0) on bus. It has 4 GPIO peripherals, pid 0xC0-0xC3.
+
 endmenu
diff --git a/drivers/spmi/Makefile b/drivers/spmi/Makefile
index 99092eb..4ca65a9 100644
--- a/drivers/spmi/Makefile
+++ b/drivers/spmi/Makefile
@@ -5,3 +5,4 @@
 #
 
 obj-$(CONFIG_SPMI)  += spmi-uclass.o
+obj-$(CONFIG_SPMI_SANDBOX) += spmi-sandbox.o
diff --git a/drivers/spmi/spmi-sandbox.c b/drivers/spmi/spmi-sandbox.c
new file mode 100644
index 0000000..2f0fea0
--- /dev/null
+++ b/drivers/spmi/spmi-sandbox.c
@@ -0,0 +1,157 @@
+/*
+ * Sample SPMI bus driver
+ *
+ * It emulates bus with single pm8916-like pmic that has only GPIO reigsters.
+ *
+ * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <spmi/spmi.h>
+#include <asm/gpio.h>
+#include <asm/io.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define EMUL_GPIO_PID_START 0xC0
+#define EMUL_GPIO_PID_END   0xC3
+
+#define EMUL_GPIO_COUNT 4
+
+#define EMUL_GPIO_REG_END 0x46 /* Last valid register */
+
+#define EMUL_PERM_R 0x1
+#define EMUL_PERM_W 0x2
+#define EMUL_PERM_RW (EMUL_PERM_R | EMUL_PERM_W)
+
+struct sandbox_emul_fake_regs {
+	u8 value;
+	u8 access_mask;
+	u8 perms; /* Access permissions */
+};
+
+struct sandbox_emul_gpio {
+	struct sandbox_emul_fake_regs r[EMUL_GPIO_REG_END]; /* Fake registers */
+};
+
+struct sandbox_spmi_priv {
+	struct sandbox_emul_gpio gpios[EMUL_GPIO_COUNT];
+};
+
+/* Check if valid register was requested */
+static bool check_address_valid(int usid, int pid, int off)
+{
+	if (usid != 0)
+		return false;
+	if (pid < EMUL_GPIO_PID_START || pid > EMUL_GPIO_PID_END)
+		return false;
+	if (off > EMUL_GPIO_REG_END)
+		return false;
+	return true;
+}
+
+static int sandbox_spmi_write(struct udevice *dev, int usid, int pid, int off,
+			  uint8_t val)
+{
+	struct sandbox_spmi_priv *priv = dev_get_priv(dev);
+	struct sandbox_emul_fake_regs *regs;
+
+	if (!check_address_valid(usid, pid, off))
+		return -EIO;
+
+	regs = priv->gpios[pid & 0x3].r; /* Last 3 bits of pid are gpio # */
+
+	switch (off) {
+	case 0x40: /* Control */
+		val &= regs[off].access_mask;
+		if (((val & 0x30) == 0x10) || ((val & 0x30) == 0x20)) {
+			/* out/inout - set status register */
+			regs[0x8].value &= ~0x1;
+			regs[0x8].value |= val & 0x1;
+		}
+		break;
+	default:
+		if (regs[off].perms & EMUL_PERM_W)
+			regs[off].value = val & regs[off].access_mask;
+	}
+	return 0;
+}
+
+static int sandbox_spmi_read(struct udevice *dev, int usid, int pid, int off)
+{
+	struct sandbox_spmi_priv *priv = dev_get_priv(dev);
+	struct sandbox_emul_fake_regs *regs;
+
+	if (!check_address_valid(usid, pid, off))
+		return -EIO;
+
+	regs = priv->gpios[pid & 0x3].r; /* Last 3 bits of pid are gpio # */
+
+	if (regs[0x46].value == 0) /* Block disabled */
+		return 0;
+
+	switch (off) {
+	case 0x8: /* Status */
+		if (regs[0x46].value == 0) /* Block disabled */
+			return 0;
+		return regs[off].value;
+	default:
+		if (regs[off].perms & EMUL_PERM_R)
+			return regs[off].value;
+		else
+			return 0;
+	}
+}
+
+static struct dm_spmi_ops sandbox_spmi_ops = {
+	.read = sandbox_spmi_read,
+	.write = sandbox_spmi_write,
+};
+
+static int sandbox_spmi_probe(struct udevice *dev)
+{
+	struct sandbox_spmi_priv *priv = dev_get_priv(dev);
+	int i;
+
+	for (i = 0; i < EMUL_GPIO_COUNT; ++i) {
+		struct sandbox_emul_fake_regs *regs = priv->gpios[i].r;
+		regs[4].perms = EMUL_PERM_R;
+		regs[4].value = 0x10;
+		regs[5].perms = EMUL_PERM_R;
+		regs[5].value = 0x5;
+		regs[8].access_mask = 0x81;
+		regs[8].perms = EMUL_PERM_RW;
+		regs[0x40].access_mask = 0x7F;
+		regs[0x40].perms = EMUL_PERM_RW;
+		regs[0x41].access_mask = 7;
+		regs[0x41].perms = EMUL_PERM_RW;
+		regs[0x42].access_mask = 7;
+		regs[0x42].perms = EMUL_PERM_RW;
+		regs[0x42].value = 0x4;
+		regs[0x45].access_mask = 0x3F;
+		regs[0x45].perms = EMUL_PERM_RW;
+		regs[0x45].value = 0x1;
+		regs[0x46].access_mask = 0x80;
+		regs[0x46].perms = EMUL_PERM_RW;
+		regs[0x46].value = 0x80;
+	}
+	return 0;
+}
+
+static const struct udevice_id sandbox_spmi_ids[] = {
+	{ .compatible = "sandbox,spmi" },
+	{ }
+};
+
+U_BOOT_DRIVER(msm_spmi) = {
+	.name = "sandbox_spmi",
+	.id = UCLASS_SPMI,
+	.of_match = sandbox_spmi_ids,
+	.ops = &sandbox_spmi_ops,
+	.probe = sandbox_spmi_probe,
+	.priv_auto_alloc_size = sizeof(struct sandbox_spmi_priv),
+};
diff --git a/test/dm/Makefile b/test/dm/Makefile
index df2d71f..9a11ae0 100644
--- a/test/dm/Makefile
+++ b/test/dm/Makefile
@@ -37,4 +37,5 @@
 obj-$(CONFIG_TIMER) += timer.o
 obj-$(CONFIG_DM_VIDEO) += video.o
 obj-$(CONFIG_ADC) += adc.o
+obj-$(CONFIG_SPMI) += spmi.o
 endif
diff --git a/test/dm/spmi.c b/test/dm/spmi.c
new file mode 100644
index 0000000..d519a90
--- /dev/null
+++ b/test/dm/spmi.c
@@ -0,0 +1,114 @@
+/*
+ * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <fdtdec.h>
+#include <dm.h>
+#include <dm/device.h>
+#include <dm/root.h>
+#include <dm/test.h>
+#include <dm/util.h>
+#include <power/pmic.h>
+#include <spmi/spmi.h>
+#include <asm/gpio.h>
+#include <test/ut.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* Test if bus childs got probed propperly*/
+static int dm_test_spmi_probe(struct unit_test_state *uts)
+{
+	const char *name = "spmi@0";
+	struct udevice *bus, *dev;
+
+	ut_assertok(uclass_get_device(UCLASS_SPMI, 0, &bus));
+
+	/* Check bus name */
+	ut_asserteq_str(name, bus->name);
+
+	/* Check that it has some devices */
+	ut_asserteq(device_has_children(bus), true);
+
+	ut_assertok(device_find_first_child(bus, &dev));
+
+	/* There should be at least one child */
+	ut_assertnonnull(dev);
+
+	/* Check that only PMICs are connected to the bus */
+	while (dev) {
+		ut_asserteq(device_get_uclass_id(dev), UCLASS_PMIC);
+		device_find_next_child(&dev);
+	}
+
+	return 0;
+}
+DM_TEST(dm_test_spmi_probe, DM_TESTF_SCAN_FDT);
+
+/* Test if it's possible to read bus directly and indirectly */
+static int dm_test_spmi_access(struct unit_test_state *uts)
+{
+	const char *pmic_name = "pm8916@0";
+	struct udevice *bus, *pmic;
+
+	ut_assertok(uclass_get_device(UCLASS_SPMI, 0, &bus));
+
+	ut_assertok(device_get_child(bus, 0, &pmic));
+
+	/* Sanity check if it's proper PMIC */
+	ut_asserteq_str(pmic_name, pmic->name);
+
+	/* Read PMIC ID reg using SPMI bus - it assumes it has slaveID == 0*/
+	ut_asserteq(spmi_reg_read(bus, 0, 0xC0, 0x4), 0x10);
+	ut_asserteq(spmi_reg_read(bus, 0, 0xC0, 0x5), 0x5);
+
+	/* Read ID reg via pmic interface */
+	ut_asserteq(pmic_reg_read(pmic, 0xC004), 0x10);
+	ut_asserteq(pmic_reg_read(pmic, 0xC005), 0x5);
+
+	return 0;
+}
+DM_TEST(dm_test_spmi_access, DM_TESTF_SCAN_FDT);
+
+
+/* Test if it's possible to access GPIO that should be in pmic */
+static int dm_test_spmi_access_peripheral(struct unit_test_state *uts)
+{
+	struct udevice *dev;
+	unsigned int offset, gpio;
+	const char *name;
+	int offset_count;
+
+	/* Get second pin of PMIC GPIO */
+	ut_assertok(gpio_lookup_name("spmi1", &dev, &offset, &gpio));
+
+	/* Check if PMIC is parent */
+	ut_asserteq(device_get_uclass_id(dev->parent), UCLASS_PMIC);
+
+	/* This should be second gpio */
+	ut_asserteq(1, offset);
+
+	name = gpio_get_bank_info(dev, &offset_count);
+
+	/* Check bank name */
+	ut_asserteq_str("spmi", name);
+	/* Check pin count */
+	ut_asserteq(4, offset_count);
+
+	ut_assertok(gpio_request(gpio, "testing"));
+
+	/* Try to set/clear gpio */
+	ut_assertok(gpio_direction_output(gpio, 0));
+	ut_asserteq(gpio_get_value(gpio), 0);
+	ut_assertok(gpio_direction_output(gpio, 1));
+	ut_asserteq(gpio_get_value(gpio), 1);
+	ut_assertok(gpio_direction_input(gpio));
+	ut_asserteq(gpio_get_value(gpio), 1);
+
+	ut_assertok(gpio_free(gpio));
+
+	return 0;
+}
+DM_TEST(dm_test_spmi_access_peripheral, DM_TESTF_SCAN_FDT);