Move source files to driver/ and power/ subdirs

The common/ subdir was getting cluttered.  Move drivers for external
components to a new driver/ tree, and move what used to be called
chipset_*.c to a new power/ directory.

This does not move/rename header files or CONFIG options.  That will
be done in subsequent steps, since moving and modifying .c files in
the same CL is harder to review.

BUG=chrome-os-partner:18343
BRANCH=none
TEST=build all boards; pass unit tests

Change-Id: I67a3003dc8564783a320335cf0e9620a21982d5e
Signed-off-by: Randall Spangler <rspangler@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/173601
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Tested-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Vic Yang <victoryang@chromium.org>

1 files changed, 166 insertions, 0 deletions

diff --git a/driver/led/ds2413.c b/driver/led/ds2413.c
new file mode 100644
index 0000000000..9babd75992
--- /dev/null
+++ b/driver/led/ds2413.c
@@ -0,0 +1,166 @@
+/* Copyright (c) 2013 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/* Power LED control for Chrome EC */
+
+#include "charge_state.h"
+#include "console.h"
+#include "hooks.h"
+#include "onewire.h"
+#include "timer.h"
+#include "util.h"
+
+#define ONEWIRE_RETRIES 10
+
+enum led_color {
+	LED_OFF = 0,
+	LED_RED,
+	LED_YELLOW,
+	LED_GREEN,
+	LED_COLOR_COUNT  /* Number of colors, not a color itself */
+};
+
+static const uint8_t led_masks[LED_COLOR_COUNT] = {0xff, 0xfe, 0xfc, 0xfd};
+static const char * const color_names[LED_COLOR_COUNT] = {
+	"off", "red", "yellow", "green"};
+
+/**
+ * Set the onewire LED GPIO controller outputs
+ *
+ * @param mask		Mask of outputs to enable
+ *
+ * @return EC_SUCCESS, or non-zero if error.
+ */
+static int led_set_mask(int mask)
+{
+	int rv;
+
+	/* Reset the 1-wire bus */
+	rv = onewire_reset();
+	if (rv)
+		return rv;
+
+	/* Skip ROM, since only one device */
+	onewire_write(0xcc);
+
+	/* Write and turn on the LEDs */
+	onewire_write(0x5a);
+	onewire_write(mask);
+	onewire_write(~mask);  /* Repeat inverted */
+
+	rv = onewire_read();   /* Confirmation byte */
+	if (rv != 0xaa)
+		return EC_ERROR_UNKNOWN;
+
+	/* The next byte is a read-back of the chip status.  Since we're only
+	 * using lines as outputs, we can ignore it. */
+	return EC_SUCCESS;
+}
+
+static int led_set(enum led_color color)
+{
+	int rv = EC_SUCCESS;
+	int i;
+
+	/*
+	 * 1-wire communication can fail for timing reasons in the current
+	 * system.  We have a limited timing window to send/receive bits, but
+	 * we can't disable interrupts for the rest of the system to guarantee
+	 * we hit that window.  Instead, simply retry the low-level command a
+	 * few times.
+	 */
+	for (i = 0; i < ONEWIRE_RETRIES; i++) {
+		rv = led_set_mask(led_masks[color]);
+		if (rv == EC_SUCCESS)
+			break;
+
+		/*
+		 * Sleep for a bit between tries.  This gives the 1-wire GPIO
+		 * chip time to recover from the failed attempt, and allows
+		 * lower-priority tasks a chance to run.
+		 */
+		usleep(100);
+	}
+
+	return rv;
+}
+
+/*****************************************************************************/
+/* Hooks */
+
+static void onewire_led_tick(void)
+{
+	static enum led_color current_color = LED_COLOR_COUNT;
+	static int tick_count;
+
+	enum led_color new_color = LED_OFF;
+	uint32_t chflags = charge_get_flags();
+
+	tick_count++;
+
+	if (!(chflags & CHARGE_FLAG_EXTERNAL_POWER)) {
+		/* AC isn't present, so the power LED on the AC plug is off */
+		current_color = LED_OFF;
+		return;
+	}
+
+	/* Translate charge state to LED color */
+	switch (charge_get_state()) {
+	case PWR_STATE_IDLE:
+		if (chflags & CHARGE_FLAG_FORCE_IDLE)
+			new_color = (tick_count & 1) ? LED_GREEN : LED_OFF;
+		else
+			new_color = LED_GREEN;
+		break;
+	case PWR_STATE_CHARGE:
+		new_color = LED_YELLOW;
+		break;
+	case PWR_STATE_CHARGE_NEAR_FULL:
+		new_color = LED_GREEN;
+		break;
+	case PWR_STATE_ERROR:
+		new_color = LED_RED;
+		break;
+	default:
+		/* Other states don't change LED color */
+		break;
+	}
+
+	/*
+	 * The power adapter on link can partially unplug and lose its LED
+	 * state.  There's no way to detect this, so just assume it forgets its
+	 * state every 10 seconds.
+	 */
+	if (!(tick_count % 10))
+		current_color = LED_COLOR_COUNT;
+
+	/* If current color is still correct, leave now */
+	if (new_color == current_color)
+		return;
+
+	/* Update LED */
+	if (!led_set(new_color))
+		current_color = new_color;
+}
+DECLARE_HOOK(HOOK_SECOND, onewire_led_tick, HOOK_PRIO_DEFAULT);
+
+/*****************************************************************************/
+/* Console commands */
+
+static int command_powerled(int argc, char **argv)
+{
+	int i;
+
+	/* Pick a color, any color... */
+	for (i = 0; i < LED_COLOR_COUNT; i++) {
+		if (!strcasecmp(argv[1], color_names[i]))
+			return led_set(i);
+	}
+	return EC_ERROR_PARAM1;
+}
+DECLARE_CONSOLE_COMMAND(powerled, command_powerled,
+			"<off | red | yellow | green>",
+			"Set power LED color",
+			NULL);