i2c_shell: Add write/read multiple-byte commands

Allow writing multiple registers (or a single 16-bit register) and
reading multiple registers.

   i2c read I2C_2 36 40
   00000000: 12 34 00 00 0F 3D 80 80 AF 9C 17 00 90 01 00 00

   i2c write I2C_2 36 40 12 34 56 78 90 12 34 56 78 90

   i2c read I2C_2 36 40
   00000000: 12 34 00 00 90 12 80 80 AF 9C 17 00 90 01 00 00

Signed-off-by: Simon Glass <[email protected]>

Author: sjg20

drivers/i2c/i2c_shell.c

@@ -19,6 +19,9 @@ LOG_MODULE_REGISTER(i2c_shell, CONFIG_LOG_DEFAULT_LEVEL);
 extern struct device __device_start[];
 extern struct device __device_end[];
 
+/* Maximum bytes we can write or read at once */
+#define MAX_I2C_BYTES	16
+
 static int cmd_i2c_scan(const struct shell *shell,
 			size_t argc, char **argv)
 {
@@ -88,6 +91,42 @@ static int cmd_i2c_recover(const struct shell *shell,
 	return 0;
 }
 
+/* i2c write <device> <dev_addr> [<byte1>, ...] */
+static int cmd_i2c_write(const struct shell *shell, size_t argc, char **argv)
+{
+	u8_t buf[MAX_I2C_BYTES];
+	struct device *dev;
+	int num_bytes;
+	int reg_addr;
+	int dev_addr;
+	int i;
+
+	dev = device_get_binding(argv[1]);
+	if (!dev) {
+		shell_error(shell, "I2C: Device driver %s not found.", argv[1]);
+		return -ENODEV;
+	}
+
+	dev_addr = strtol(argv[2], NULL, 16);
+	reg_addr = strtol(argv[3], NULL, 16);
+	num_bytes = argc - 4;
+	if (num_bytes < 0)
+		return 0;
+	if (num_bytes > MAX_I2C_BYTES) {
+		num_bytes = MAX_I2C_BYTES;
+	}
+	for (i = 0; i < num_bytes; i++) {
+		buf[i] = (uint8_t)strtol(argv[4 + i], NULL, 16);
+	}
+
+	if (i2c_burst_write(dev, dev_addr, reg_addr, buf, num_bytes) < 0) {
+		shell_error(shell, "Failed to write to device: %s", argv[1]);
+		return -EIO;
+	}
+
+	return 0;
+}
+
 static int cmd_i2c_write_byte(const struct shell *shell,
 			      size_t argc, char **argv)
 {
@@ -143,6 +182,41 @@ static int cmd_i2c_read_byte(const struct shell *shell,
 	return 0;
 }
 
+/* i2c read <device> <dev_addr> [<numbytes>] */
+static int cmd_i2c_read(const struct shell *shell, size_t argc, char **argv)
+{
+	u8_t buf[MAX_I2C_BYTES];
+	struct device *dev;
+	int num_bytes;
+	int reg_addr;
+	int dev_addr;
+
+	dev = device_get_binding(argv[1]);
+	if (!dev) {
+		shell_error(shell, "I2C: Device driver %s not found.", argv[1]);
+		return -ENODEV;
+	}
+
+	dev_addr = strtol(argv[2], NULL, 16);
+	reg_addr = strtol(argv[3], NULL, 16);
+	if (argc > 4) {
+		num_bytes = strtol(argv[4], NULL, 16);
+		if (num_bytes > MAX_I2C_BYTES)
+			num_bytes = MAX_I2C_BYTES;
+	} else {
+		num_bytes = MAX_I2C_BYTES;
+	}
+
+	if (i2c_burst_read(dev, dev_addr, reg_addr, buf, num_bytes) < 0) {
+		shell_error(shell, "Failed to read from device: %s", argv[1]);
+		return -EIO;
+	}
+
+	shell_hexdump(shell, buf, num_bytes);
+
+	return 0;
+}
+
 static void device_name_get(size_t idx, struct shell_static_entry *entry);
 
 SHELL_DYNAMIC_CMD_CREATE(dsub_device_name, device_name_get);
@@ -175,9 +249,15 @@ SHELL_STATIC_SUBCMD_SET_CREATE(sub_i2c_cmds,
 					 "Scan I2C devices", cmd_i2c_scan),
 			       SHELL_CMD(recover, &dsub_device_name,
 					 "Recover I2C bus", cmd_i2c_recover),
+			       SHELL_CMD_ARG(read, &dsub_device_name,
+					     "Read bytes from an I2C device",
+					     cmd_i2c_read, 3, MAX_I2C_BYTES),
 			       SHELL_CMD_ARG(read_byte, &dsub_device_name,
 					     "Read a byte from an I2C device",
 					     cmd_i2c_read_byte, 3, 1),
+			       SHELL_CMD_ARG(write, &dsub_device_name,
+					     "Write bytes to an I2C device",
+					     cmd_i2c_write, 3, MAX_I2C_BYTES),
 			       SHELL_CMD_ARG(write_byte, &dsub_device_name,
 					     "Write a byte to an I2C device",
 					     cmd_i2c_write_byte, 4, 1),