dm: i2c: Add tests for I2C

Add some basic tests to check that the system works as expected.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Heiko Schocher <hs@denx.de>
diff --git a/include/dm/ut.h b/include/dm/ut.h
index fa9eac0..ec61465 100644
--- a/include/dm/ut.h
+++ b/include/dm/ut.h
@@ -89,6 +89,18 @@
 	}								\
 }
 
+/* Assert that a pointer is not NULL */
+#define ut_assertnonnull(expr) {					\
+	const void *val = (expr);					\
+									\
+	if (val == NULL) {						\
+		ut_failf(dms, __FILE__, __LINE__, __func__,		\
+			 #expr " = NULL",				\
+			 "Expected non-null, got NULL");		\
+		return -1;						\
+	}								\
+}
+
 /* Assert that an operation succeeds (returns 0) */
 #define ut_assertok(cond)	ut_asserteq(0, cond)
 
diff --git a/test/dm/Makefile b/test/dm/Makefile
index 75d3d41..612aa95 100644
--- a/test/dm/Makefile
+++ b/test/dm/Makefile
@@ -20,4 +20,5 @@
 obj-$(CONFIG_DM_GPIO) += gpio.o
 obj-$(CONFIG_DM_SPI) += spi.o
 obj-$(CONFIG_DM_SPI_FLASH) += sf.o
+obj-$(CONFIG_DM_I2C) += i2c.o
 endif
diff --git a/test/dm/i2c.c b/test/dm/i2c.c
new file mode 100644
index 0000000..a53e28d
--- /dev/null
+++ b/test/dm/i2c.c
@@ -0,0 +1,216 @@
+/*
+ * Copyright (C) 2013 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * Note: Test coverage does not include 10-bit addressing
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <fdtdec.h>
+#include <i2c.h>
+#include <dm/device-internal.h>
+#include <dm/test.h>
+#include <dm/uclass-internal.h>
+#include <dm/ut.h>
+#include <dm/util.h>
+#include <asm/state.h>
+#include <asm/test.h>
+
+static const int busnum;
+static const int chip = 0x2c;
+
+/* Test that we can find buses and chips */
+static int dm_test_i2c_find(struct dm_test_state *dms)
+{
+	struct udevice *bus, *dev;
+	const int no_chip = 0x10;
+
+	ut_asserteq(-ENODEV, uclass_find_device_by_seq(UCLASS_I2C, busnum,
+						       false, &bus));
+
+	/*
+	 * i2c_post_bind() will bind devices to chip selects. Check this then
+	 * remove the emulation and the slave device.
+	 */
+	ut_assertok(uclass_get_device_by_seq(UCLASS_I2C, busnum, &bus));
+	ut_assertok(i2c_probe(bus, chip, 0, &dev));
+	ut_asserteq(-ENODEV, i2c_probe(bus, no_chip, 0, &dev));
+	ut_asserteq(-ENODEV, uclass_get_device_by_seq(UCLASS_I2C, 1, &bus));
+
+	return 0;
+}
+DM_TEST(dm_test_i2c_find, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+static int dm_test_i2c_read_write(struct dm_test_state *dms)
+{
+	struct udevice *bus, *dev;
+	uint8_t buf[5];
+
+	ut_assertok(uclass_get_device_by_seq(UCLASS_I2C, busnum, &bus));
+	ut_assertok(i2c_get_chip(bus, chip, &dev));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\0\0\0\0", sizeof(buf)));
+	ut_assertok(i2c_write(dev, 2, (uint8_t *)"AB", 2));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\0AB\0", sizeof(buf)));
+
+	return 0;
+}
+DM_TEST(dm_test_i2c_read_write, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+static int dm_test_i2c_speed(struct dm_test_state *dms)
+{
+	struct udevice *bus, *dev;
+	uint8_t buf[5];
+
+	ut_assertok(uclass_get_device_by_seq(UCLASS_I2C, busnum, &bus));
+	ut_assertok(i2c_get_chip(bus, chip, &dev));
+	ut_assertok(i2c_set_bus_speed(bus, 100000));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(i2c_set_bus_speed(bus, 400000));
+	ut_asserteq(400000, i2c_get_bus_speed(bus));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_asserteq(-EINVAL, i2c_write(dev, 0, buf, 5));
+
+	return 0;
+}
+DM_TEST(dm_test_i2c_speed, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+static int dm_test_i2c_offset_len(struct dm_test_state *dms)
+{
+	struct udevice *bus, *dev;
+	uint8_t buf[5];
+
+	ut_assertok(uclass_get_device_by_seq(UCLASS_I2C, busnum, &bus));
+	ut_assertok(i2c_get_chip(bus, chip, &dev));
+	ut_assertok(i2c_set_chip_offset_len(dev, 1));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+
+	/* This is not supported by the uclass */
+	ut_asserteq(-EINVAL, i2c_set_chip_offset_len(dev, 5));
+
+	return 0;
+}
+DM_TEST(dm_test_i2c_offset_len, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+static int dm_test_i2c_probe_empty(struct dm_test_state *dms)
+{
+	struct udevice *bus, *dev;
+
+	ut_assertok(uclass_get_device_by_seq(UCLASS_I2C, busnum, &bus));
+	ut_assertok(i2c_probe(bus, SANDBOX_I2C_TEST_ADDR, 0, &dev));
+
+	return 0;
+}
+DM_TEST(dm_test_i2c_probe_empty, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+static int dm_test_i2c_bytewise(struct dm_test_state *dms)
+{
+	struct udevice *bus, *dev;
+	struct udevice *eeprom;
+	uint8_t buf[5];
+
+	ut_assertok(uclass_get_device_by_seq(UCLASS_I2C, busnum, &bus));
+	ut_assertok(i2c_get_chip(bus, chip, &dev));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\0\0\0\0", sizeof(buf)));
+
+	/* Tell the EEPROM to only read/write one register at a time */
+	ut_assertok(uclass_first_device(UCLASS_I2C_EMUL, &eeprom));
+	ut_assertnonnull(eeprom);
+	sandbox_i2c_eeprom_set_test_mode(eeprom, SIE_TEST_MODE_SINGLE_BYTE);
+
+	/* Now we only get the first byte - the rest will be 0xff */
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\xff\xff\xff\xff", sizeof(buf)));
+
+	/* If we do a separate transaction for each byte, it works */
+	ut_assertok(i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\0\0\0\0", sizeof(buf)));
+
+	/* This will only write A */
+	ut_assertok(i2c_set_chip_flags(dev, 0));
+	ut_assertok(i2c_write(dev, 2, (uint8_t *)"AB", 2));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\xff\xff\xff\xff", sizeof(buf)));
+
+	/* Check that the B was ignored */
+	ut_assertok(i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\0A\0\0\0", sizeof(buf)));
+
+	/* Now write it again with the new flags, it should work */
+	ut_assertok(i2c_set_chip_flags(dev, DM_I2C_CHIP_WR_ADDRESS));
+	ut_assertok(i2c_write(dev, 2, (uint8_t *)"AB", 2));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\xff\xff\xff\xff", sizeof(buf)));
+
+	ut_assertok(i2c_set_chip_flags(dev, DM_I2C_CHIP_WR_ADDRESS |
+						DM_I2C_CHIP_RD_ADDRESS));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "\0\0AB\0\0", sizeof(buf)));
+
+	/* Restore defaults */
+	sandbox_i2c_eeprom_set_test_mode(eeprom, SIE_TEST_MODE_NONE);
+	ut_assertok(i2c_set_chip_flags(dev, 0));
+
+	return 0;
+}
+DM_TEST(dm_test_i2c_bytewise, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
+
+static int dm_test_i2c_offset(struct dm_test_state *dms)
+{
+	struct udevice *eeprom;
+	struct udevice *dev;
+	uint8_t buf[5];
+
+	ut_assertok(i2c_get_chip_for_busnum(busnum, chip, &dev));
+
+	/* Do a transfer so we can find the emulator */
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(uclass_first_device(UCLASS_I2C_EMUL, &eeprom));
+
+	/* Offset length 0 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 0);
+	ut_assertok(i2c_set_chip_offset_len(dev, 0));
+	ut_assertok(i2c_write(dev, 10 /* ignored */, (uint8_t *)"AB", 2));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "AB\0\0\0\0", sizeof(buf)));
+
+	/* Offset length 1 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 1);
+	ut_assertok(i2c_set_chip_offset_len(dev, 1));
+	ut_assertok(i2c_write(dev, 2, (uint8_t *)"AB", 2));
+	ut_assertok(i2c_read(dev, 0, buf, 5));
+	ut_assertok(memcmp(buf, "ABAB\0", sizeof(buf)));
+
+	/* Offset length 2 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 2);
+	ut_assertok(i2c_set_chip_offset_len(dev, 2));
+	ut_assertok(i2c_write(dev, 0x210, (uint8_t *)"AB", 2));
+	ut_assertok(i2c_read(dev, 0x210, buf, 5));
+	ut_assertok(memcmp(buf, "AB\0\0\0", sizeof(buf)));
+
+	/* Offset length 3 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 2);
+	ut_assertok(i2c_set_chip_offset_len(dev, 2));
+	ut_assertok(i2c_write(dev, 0x410, (uint8_t *)"AB", 2));
+	ut_assertok(i2c_read(dev, 0x410, buf, 5));
+	ut_assertok(memcmp(buf, "AB\0\0\0", sizeof(buf)));
+
+	/* Offset length 4 */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 2);
+	ut_assertok(i2c_set_chip_offset_len(dev, 2));
+	ut_assertok(i2c_write(dev, 0x420, (uint8_t *)"AB", 2));
+	ut_assertok(i2c_read(dev, 0x420, buf, 5));
+	ut_assertok(memcmp(buf, "AB\0\0\0", sizeof(buf)));
+
+	/* Restore defaults */
+	sandbox_i2c_eeprom_set_offset_len(eeprom, 1);
+
+	return 0;
+}
+DM_TEST(dm_test_i2c_offset, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);
diff --git a/test/dm/test.dts b/test/dm/test.dts
index 1fba792..fb0272a 100644
--- a/test/dm/test.dts
+++ b/test/dm/test.dts
@@ -93,6 +93,23 @@
 		num-gpios = <10>;
 	};
 
+	i2c@0 {
+		#address-cells = <1>;
+		#size-cells = <0>;
+		reg = <0>;
+		compatible = "sandbox,i2c";
+		clock-frequency = <100000>;
+		eeprom@2c {
+			reg = <0x2c>;
+			compatible = "i2c-eeprom";
+			emul {
+				compatible = "sandbox,i2c-eeprom";
+				sandbox,filename = "i2c.bin";
+				sandbox,size = <256>;
+			};
+		};
+	};
+
 	spi@0 {
 		#address-cells = <1>;
 		#size-cells = <0>;