1 files changed, 108 insertions, 0 deletions
diff --git a/board/zinger/usb_pd_policy.c b/board/zinger/usb_pd_policy.c
new file mode 100644
index 0000000000..5f314185a3
--- /dev/null
+++ b/board/zinger/usb_pd_policy.c
@@ -0,0 +1,108 @@
+/* Copyright (c) 2014 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.
+ */
+
+#include "board.h"
+#include "common.h"
+#include "console.h"
+#include "debug.h"
+#include "hooks.h"
+#include "registers.h"
+#include "util.h"
+#include "usb_pd.h"
+
+/* ------------------------- Power supply control ------------------------ */
+
+/* GPIO level setting helpers through BSRR register */
+#define GPIO_SET(n)   (1 << (n))
+#define GPIO_RESET(n) (1 << ((n) + 16))
+
+/* Output voltage selection */
+enum volt {
+	VO_5V  = GPIO_RESET(13) | GPIO_RESET(14),
+	VO_12V = GPIO_SET(13)   | GPIO_RESET(14),
+	VO_13V = GPIO_RESET(13) | GPIO_SET(14),
+	VO_20V = GPIO_SET(13)   | GPIO_SET(14),
+};
+
+static inline void set_output_voltage(enum volt v)
+{
+	/* set voltage_select on PA13/PA14 */
+	STM32_GPIO_BSRR(GPIO_A) = v;
+}
+
+static inline void output_enable(void)
+{
+	/* GPF0 (FET driver shutdown) = 0 */
+	STM32_GPIO_BSRR(GPIO_F) = GPIO_RESET(0);
+}
+
+static inline void output_disable(void)
+{
+	/* GPF0 (FET driver shutdown) = 1 */
+	STM32_GPIO_BSRR(GPIO_F) = GPIO_SET(0);
+}
+
+/* ----------------------- USB Power delivery policy ---------------------- */
+
+/* Power Delivery Objects */
+const uint32_t pd_src_pdo[] = {
+		PDO_FIXED(5000,   500, PDO_FIXED_EXTERNAL),
+		PDO_FIXED(5000,  3000, 0),
+		PDO_FIXED(12000, 3000, 0),
+		PDO_FIXED(20000, 2000, 0),
+};
+const int pd_src_pdo_cnt = ARRAY_SIZE(pd_src_pdo);
+
+/* PDO voltages (should match the table above) */
+static enum volt voltages[ARRAY_SIZE(pd_src_pdo)] = {
+	VO_5V,
+	VO_5V,
+	VO_12V,
+	VO_20V,
+};
+
+int pd_request_voltage(uint32_t rdo)
+{
+	int op_ma = rdo & 0x3FF;
+	int max_ma = (rdo >> 10) & 0x3FF;
+	int idx = rdo >> 28;
+	uint32_t pdo;
+	uint32_t pdo_ma;
+
+	if (!idx || idx > pd_src_pdo_cnt)
+		return EC_ERROR_INVAL; /* Invalid index */
+
+	/* check current ... */
+	pdo = pd_src_pdo[idx - 1];
+	pdo_ma = (pdo & 0x3ff);
+	if (op_ma > pdo_ma)
+		return EC_ERROR_INVAL; /* too much op current */
+	if (max_ma > pdo_ma)
+		return EC_ERROR_INVAL; /* too much max current */
+
+	debug_printf("Switch to %d V %d mA (for %d/%d mA)\n",
+		     ((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
+		     ((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
+
+	output_disable();
+	/* TODO discharge ? */
+	set_output_voltage(voltages[idx-1]);
+
+	return EC_SUCCESS;
+}
+
+int pd_set_power_supply_ready(void)
+{
+	output_enable();
+	return EC_SUCCESS; /* we are ready */
+}
+
+void pd_power_supply_reset(void)
+{
+	output_disable();
+	/* TODO discharge ? */
+	set_output_voltage(VO_5V);
+	/* TODO transition delay */
+}