common/i2c: Implement i2cspeed console command

This adds the "i2cspeed port [speed]" console command. If only the port
number is given, then the current port bus speed is reported. With 2
arguments, the port bus speed is changed. Valid speeds are 100, 400,
1000 and the unit is kHz.

BRANCH=none
BUG=b:201039003
TEST=with follow-on patches, switched I2C bus speed between 400 kHz
	and 1 MHz.

Change-Id: I7ca6b2c7a8fd9abe8e8ec77e4d1702529b297fe8
Signed-off-by: Caveh Jalali <caveh@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3181504
Reviewed-by: Keith Short <keithshort@chromium.org>
Commit-Queue: Keith Short <keithshort@chromium.org>

4 files changed, 90 insertions, 0 deletions

diff --git a/common/i2c_controller.c b/common/i2c_controller.c
index 9fd68aaa2d..59aff3d69e 100644
--- a/common/i2c_controller.c
+++ b/common/i2c_controller.c
@@ -1724,6 +1724,80 @@ DECLARE_CONSOLE_COMMAND(i2cxfer, command_i2cxfer,
 			"Read write I2C");
 #endif
 
+#ifdef CONFIG_CMD_I2C_SPEED
+
+static const char * const i2c_freq_str[] = {
+	[I2C_FREQ_1000KHZ] = "1000 kHz",
+	[I2C_FREQ_400KHZ] = "400 kHz",
+	[I2C_FREQ_100KHZ] = "100 kHz",
+	[I2C_FREQ_COUNT] = "unknown",
+};
+
+BUILD_ASSERT(ARRAY_SIZE(i2c_freq_str) == I2C_FREQ_COUNT + 1);
+
+static int command_i2c_speed(int argc, char **argv)
+{
+	int port;
+	char *e;
+	enum i2c_freq freq;
+	enum i2c_freq new_freq = I2C_FREQ_COUNT;
+
+	if (argc < 2 || argc > 3)
+		return EC_ERROR_PARAM_COUNT;
+
+	port = strtoi(argv[1], &e, 0);
+	if (*e)
+		return EC_ERROR_PARAM1;
+
+	if (port < 0 || port >= I2C_PORT_COUNT)
+		return EC_ERROR_INVAL;
+
+	freq = i2c_get_freq(port);
+	if (freq < 0 || freq > I2C_FREQ_COUNT)
+		return EC_ERROR_UNKNOWN;
+
+	if (argc == 3) {
+		int khz;
+		int rv;
+
+		khz = strtoi(argv[2], &e, 0);
+		if (*e)
+			return EC_ERROR_PARAM2;
+
+		switch (khz) {
+		case 100:
+			new_freq = I2C_FREQ_100KHZ;
+			break;
+		case 400:
+			new_freq = I2C_FREQ_400KHZ;
+			break;
+		case 1000:
+			new_freq = I2C_FREQ_1000KHZ;
+			break;
+		default:
+			return EC_ERROR_PARAM2;
+		}
+		rv = i2c_set_freq(port, new_freq);
+		if (rv != EC_SUCCESS)
+			return rv;
+	}
+
+	if (new_freq != I2C_FREQ_COUNT)
+		ccprintf("Port %d speed changed from %s to %s\n", port,
+			 i2c_freq_str[freq],
+			 i2c_freq_str[new_freq]);
+	else
+		ccprintf("Port %d speed is %s\n", port, i2c_freq_str[freq]);
+
+	return EC_SUCCESS;
+}
+
+DECLARE_CONSOLE_COMMAND(i2cspeed, command_i2c_speed,
+			"port [speed in kHz]",
+			"Get or set I2C port speed");
+
+#endif /* CONFIG_CMD_I2C_SPEED */
+
 #ifdef CONFIG_CMD_I2C_STRESS_TEST
 static void i2c_test_status(struct i2c_test_results *i2c_test, int test_dev)
 {
diff --git a/include/config.h b/include/config.h
index 5c0975c713..2753cc715c 100644
--- a/include/config.h
+++ b/include/config.h
@@ -1418,6 +1418,7 @@
 #undef  CONFIG_CMD_I2CWEDGE
 #undef  CONFIG_CMD_I2C_PROTECT
 #define CONFIG_CMD_I2C_SCAN
+#undef  CONFIG_CMD_I2C_SPEED
 #undef  CONFIG_CMD_I2C_STRESS_TEST
 #undef  CONFIG_CMD_I2C_STRESS_TEST_ACCEL
 #undef  CONFIG_CMD_I2C_STRESS_TEST_ALS
diff --git a/zephyr/Kconfig b/zephyr/Kconfig
index 2f4a653fea..07f09ae46e 100644
--- a/zephyr/Kconfig
+++ b/zephyr/Kconfig
@@ -484,6 +484,16 @@ config PLATFORM_EC_CONSOLE_CMD_I2C_PORTMAP
 	  display the mapping of the I2C ports defined by the named-i2c-ports
 	  node to the physical port and remote port indexes.
 
+config PLATFORM_EC_CONSOLE_CMD_I2C_SPEED
+	bool "Console command: i2cspeed"
+	default n
+	depends on PLATFORM_EC_I2C
+	help
+	  Enable the 'i2cspeed' console command. This comamnd is used to
+	  display an I2C port's bus speed. Additionally, for ports with
+	  the DYNAMIC_SPEED port flag set, the speed can be set. In all
+	  cases, the bus speed is in units of kHz.
+
 config PLATFORM_EC_SMBUS_PEC
 	bool "Packet error checking support for SMBus"
 	help
diff --git a/zephyr/shim/include/config_chip.h b/zephyr/shim/include/config_chip.h
index a19a2e1775..04d2ca1d5d 100644
--- a/zephyr/shim/include/config_chip.h
+++ b/zephyr/shim/include/config_chip.h
@@ -169,6 +169,11 @@
 #define CONFIG_I2C_PASSTHRU_RESTRICTED
 #endif
 
+#undef CONFIG_CMD_I2C_SPEED
+#ifdef CONFIG_PLATFORM_EC_CONSOLE_CMD_I2C_SPEED
+#define CONFIG_CMD_I2C_SPEED
+#endif
+
 #undef CONFIG_BATTERY_PRESENT_CUSTOM
 #ifdef CONFIG_PLATFORM_EC_BATTERY_PRESENT_CUSTOM
 #define CONFIG_BATTERY_PRESENT_CUSTOM