driver/usb_switch_tsu6721.c - chromiumos/platform/ec - Git at Google

 /* Copyright (c) 2012 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.
  *
  * TI TSU6721 USB port switch driver.
  */

 #include "console.h"
 #include "ec_commands.h"
 #include "hooks.h"
 #include "host_command.h"
 #include "i2c.h"
 #include "system.h"
 #include "timer.h"
 #include "tsu6721.h"
 #include "util.h"

 /* Console output macros */
 #define CPUTS(outstr) cputs(CC_USBCHARGE, outstr)
 #define CPRINTS(format, args...) cprints(CC_USBCHARGE, format, ## args)

 /* 8-bit I2C address */
 #define TSU6721_I2C_ADDR (0x25 << 1)

 /* Delay values */
 #define TSU6721_SW_RESET_DELAY 15

 /* Number of retries when reset fails */
 #define TSU6721_SW_RESET_RETRY 3

 static int saved_interrupts;

 uint8_t tsu6721_read(uint8_t reg)
 {
 	int res;
 	int val;

 	res = i2c_read8(I2C_PORT_MASTER, TSU6721_I2C_ADDR, reg, &val);
 	if (res)
 		return 0xee;

 	return val;
 }

 int tsu6721_write(uint8_t reg, uint8_t val)
 {
 	int res;

 	res = i2c_write8(I2C_PORT_MASTER, TSU6721_I2C_ADDR, reg, val);
 	if (res)
 		CPRINTS("TSU6721 I2C write failed");
 	return res;
 }

 int tsu6721_enable_interrupts(void)
 {
 	int ctrl = tsu6721_read(TSU6721_REG_CONTROL);
 	return tsu6721_write(TSU6721_REG_CONTROL, ctrl & 0x1e);
 }

 int  tsu6721_disable_interrupts(void)
 {
 	int ctrl = tsu6721_read(TSU6721_REG_CONTROL);
 	int rv;

 	rv = tsu6721_write(TSU6721_REG_CONTROL, ctrl | 0x1);
 	tsu6721_get_interrupts();
 	return rv;
 }

 int  tsu6721_set_interrupt_mask(uint16_t mask)
 {
 	return tsu6721_write(TSU6721_REG_INT_MASK1, (~mask) & 0xff) |
 	       tsu6721_write(TSU6721_REG_INT_MASK2, ((~mask) >> 8) & 0xff);
 }

 int tsu6721_get_interrupts(void)
 {
 	int ret = tsu6721_peek_interrupts();
 	saved_interrupts = 0;
 	return ret;
 }

 int tsu6721_peek_interrupts(void)
 {
 	saved_interrupts |= (tsu6721_read(TSU6721_REG_INT2) << 8) |
 			    (tsu6721_read(TSU6721_REG_INT1));
 	return saved_interrupts;
 }

 int tsu6721_get_device_type(void)
 {
 	return (tsu6721_read(TSU6721_REG_DEV_TYPE3) << 16) |
 	       (tsu6721_read(TSU6721_REG_DEV_TYPE2) << 8) |
 	       (tsu6721_read(TSU6721_REG_DEV_TYPE1));
 }

 void tsu6721_reset(void)
 {
 	int i;

 	for (i = 0; i < TSU6721_SW_RESET_RETRY; ++i) {
 		if (i != 0) {
 			CPRINTS("TSU6721 init failed. Retrying");
 			msleep(500);
 		}
 		if (tsu6721_write(TSU6721_REG_RESET, 0x1))
 			continue;
 		/* TSU6721 reset takes ~10ms. Let's wait for 15ms to be safe. */
 		msleep(TSU6721_SW_RESET_DELAY);
 		if (tsu6721_init() == EC_SUCCESS)
 			break;
 	}
 }

 int tsu6721_mux(enum tsu6721_mux sel)
 {
 	uint8_t id = tsu6721_read(TSU6721_REG_ADC);
 	uint8_t vbus1 = tsu6721_read(TSU6721_REG_DEV_TYPE1) & 0x74;
 	uint8_t vbus3 = tsu6721_read(TSU6721_REG_DEV_TYPE3) & 0x74;
 	uint8_t ctrl = tsu6721_read(TSU6721_REG_CONTROL);

 	/*
 	 * silicon limitation: the chip stays in low power mode and cannot
 	 * activate manual mode if it is not detecting either a VBUS or
 	 * something known on the ID pin
 	 */
 	if (sel != TSU6721_MUX_AUTO && (id == 0x1f) && !vbus1 && !vbus3) {
 		CPRINTS("TSU6721 cannot use manual mode: no VBUS or ID");
 		return EC_ERROR_INVAL;
 	}

 	if (sel == TSU6721_MUX_AUTO) {
 		tsu6721_write(TSU6721_REG_CONTROL, ctrl | TSU6721_CTRL_AUTO);
 	} else {
 		tsu6721_write(TSU6721_REG_MANUAL1, sel);
 		tsu6721_write(TSU6721_REG_CONTROL, ctrl & ~TSU6721_CTRL_AUTO);
 	}

 	return EC_SUCCESS;
 }

 void tsu6721_set_pins(int mask)
 {
 	tsu6721_write(TSU6721_REG_MANUAL2, mask);
 }

 int tsu6721_init(void)
 {
 	uint8_t settings;
 	uint8_t dev_id = tsu6721_read(TSU6721_REG_DEV_ID);
 	int res = 0;

 	if ((dev_id != 0x0a) && (dev_id != 0x12)) {
 		CPRINTS("TSU6721 invalid device ID 0x%02x", dev_id);
 		return EC_ERROR_UNKNOWN;
 	}

 	/* set USB charger detection timeout to 600ms */
 	settings = tsu6721_read(TSU6721_REG_TIMER);
 	if (settings == 0xee)
 		return EC_ERROR_UNKNOWN;
 	settings = (settings & ~0x38);
 	res |= tsu6721_write(TSU6721_REG_TIMER, settings);

 	res |= tsu6721_set_interrupt_mask(TSU6721_INT_ATTACH |
 					  TSU6721_INT_DETACH |
 					  TSU6721_INT_ADC_CHANGE |
 					  TSU6721_INT_VBUS);
 	res |= tsu6721_enable_interrupts();

 	return res ? EC_ERROR_UNKNOWN : EC_SUCCESS;
 }
 /*
  * TODO(crosbug.com/p/23741): Using I2C early in the HOOK_INIT currently
  * triggers all sort of badness.  Debug this before re-activating
  * initialization in HOOK_INIT.
  */
 #if 0
 DECLARE_HOOK(HOOK_INIT, tsu6721_init, HOOK_PRIO_DEFAULT);
 #endif

 static void tsu6721_dump(void)
 {
 	int i;
 	uint8_t id = tsu6721_read(TSU6721_REG_ADC);
 	uint8_t ctrl = tsu6721_read(TSU6721_REG_CONTROL);

 	if (ctrl & TSU6721_CTRL_AUTO)
 		ccprintf("Auto: %02x %02x %02x\n",
 			tsu6721_read(TSU6721_REG_DEV_TYPE1),
 			tsu6721_read(TSU6721_REG_DEV_TYPE2),
 			tsu6721_read(TSU6721_REG_DEV_TYPE3));
 	else
 		ccprintf("Manual: %02x %02x\n",
 			tsu6721_read(TSU6721_REG_MANUAL1),
 			tsu6721_read(TSU6721_REG_MANUAL2));
 	ccprintf("ID: 0x%02x\n", id);
 	for (i = 1; i < 0x24; i++)
 		ccprintf("%02x ", tsu6721_read(i));
 	ccprintf("\n");
 }

 /*****************************************************************************/
 /* Console commands */
 #ifdef CONFIG_CMD_USBMUX
 static int command_usbmux(int argc, char **argv)
 {
 	if (1 == argc) { /* dump all registers */
 		tsu6721_dump();
 		return EC_SUCCESS;
 	} else if (2 == argc) {
 		if (!strcasecmp(argv[1], "usb")) {
 			tsu6721_mux(TSU6721_MUX_USB);
 		} else if (!strcasecmp(argv[1], "uart1")) {
 			tsu6721_mux(TSU6721_MUX_UART);
 		} else if (!strcasecmp(argv[1], "uart2")) {
 			tsu6721_mux(TSU6721_MUX_AUDIO);
 		} else if (!strcasecmp(argv[1], "auto")) {
 			tsu6721_mux(TSU6721_MUX_AUTO);
 		} else { /* read one register */
 			ccprintf("Invalid mux value: %s\n", argv[1]);
 			return EC_ERROR_INVAL;
 		}
 		return EC_SUCCESS;
 	}

 	return EC_ERROR_INVAL;
 }
 DECLARE_CONSOLE_COMMAND(usbmux, command_usbmux,
 			"[usb|uart1|uart2|auto]",
 			"TSU6721 USB mux control",
 			NULL);
 #endif

 /*****************************************************************************/
 /* Host commands */

 static int usb_command_mux(struct host_cmd_handler_args *args)
 {
 	const struct ec_params_usb_mux *p = args->params;

 	if (system_is_locked())
 		return EC_RES_ACCESS_DENIED;

 	/* Safety check */
 	if (p->mux != TSU6721_MUX_AUTO &&
 	    p->mux != TSU6721_MUX_USB &&
 	    p->mux != TSU6721_MUX_UART &&
 	    p->mux != TSU6721_MUX_AUDIO)
 		return EC_RES_ERROR;

 	if (tsu6721_mux(p->mux))
 		return EC_RES_ERROR;
 	return EC_RES_SUCCESS;
 }
 DECLARE_HOST_COMMAND(EC_CMD_USB_MUX, usb_command_mux, EC_VER_MASK(0));
	/* Copyright (c) 2012 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.
	*
	* TI TSU6721 USB port switch driver.
	*/

	#include "console.h"
	#include "ec_commands.h"
	#include "hooks.h"
	#include "host_command.h"
	#include "i2c.h"
	#include "system.h"
	#include "timer.h"
	#include "tsu6721.h"
	#include "util.h"

	/* Console output macros */
	#define CPUTS(outstr) cputs(CC_USBCHARGE, outstr)
	#define CPRINTS(format, args...) cprints(CC_USBCHARGE, format, ## args)

	/* 8-bit I2C address */
	#define TSU6721_I2C_ADDR (0x25 << 1)

	/* Delay values */
	#define TSU6721_SW_RESET_DELAY 15

	/* Number of retries when reset fails */
	#define TSU6721_SW_RESET_RETRY 3

	static int saved_interrupts;

	uint8_t tsu6721_read(uint8_t reg)
	{
	int res;
	int val;

	res = i2c_read8(I2C_PORT_MASTER, TSU6721_I2C_ADDR, reg, &val);
	if (res)
	return 0xee;

	return val;
	}

	int tsu6721_write(uint8_t reg, uint8_t val)
	{
	int res;

	res = i2c_write8(I2C_PORT_MASTER, TSU6721_I2C_ADDR, reg, val);
	if (res)
	CPRINTS("TSU6721 I2C write failed");
	return res;
	}

	int tsu6721_enable_interrupts(void)
	{
	int ctrl = tsu6721_read(TSU6721_REG_CONTROL);
	return tsu6721_write(TSU6721_REG_CONTROL, ctrl & 0x1e);
	}

	int tsu6721_disable_interrupts(void)
	{
	int ctrl = tsu6721_read(TSU6721_REG_CONTROL);
	int rv;

	rv = tsu6721_write(TSU6721_REG_CONTROL, ctrl \| 0x1);
	tsu6721_get_interrupts();
	return rv;
	}

	int tsu6721_set_interrupt_mask(uint16_t mask)
	{
	return tsu6721_write(TSU6721_REG_INT_MASK1, (~mask) & 0xff) \|
	tsu6721_write(TSU6721_REG_INT_MASK2, ((~mask) >> 8) & 0xff);
	}

	int tsu6721_get_interrupts(void)
	{
	int ret = tsu6721_peek_interrupts();
	saved_interrupts = 0;
	return ret;
	}

	int tsu6721_peek_interrupts(void)
	{
	saved_interrupts \|= (tsu6721_read(TSU6721_REG_INT2) << 8) \|
	(tsu6721_read(TSU6721_REG_INT1));
	return saved_interrupts;
	}

	int tsu6721_get_device_type(void)
	{
	return (tsu6721_read(TSU6721_REG_DEV_TYPE3) << 16) \|
	(tsu6721_read(TSU6721_REG_DEV_TYPE2) << 8) \|
	(tsu6721_read(TSU6721_REG_DEV_TYPE1));
	}

	void tsu6721_reset(void)
	{
	int i;

	for (i = 0; i < TSU6721_SW_RESET_RETRY; ++i) {
	if (i != 0) {
	CPRINTS("TSU6721 init failed. Retrying");
	msleep(500);
	}
	if (tsu6721_write(TSU6721_REG_RESET, 0x1))
	continue;
	/* TSU6721 reset takes ~10ms. Let's wait for 15ms to be safe. */
	msleep(TSU6721_SW_RESET_DELAY);
	if (tsu6721_init() == EC_SUCCESS)
	break;
	}
	}

	int tsu6721_mux(enum tsu6721_mux sel)
	{
	uint8_t id = tsu6721_read(TSU6721_REG_ADC);
	uint8_t vbus1 = tsu6721_read(TSU6721_REG_DEV_TYPE1) & 0x74;
	uint8_t vbus3 = tsu6721_read(TSU6721_REG_DEV_TYPE3) & 0x74;
	uint8_t ctrl = tsu6721_read(TSU6721_REG_CONTROL);

	/*
	* silicon limitation: the chip stays in low power mode and cannot
	* activate manual mode if it is not detecting either a VBUS or
	* something known on the ID pin
	*/
	if (sel != TSU6721_MUX_AUTO && (id == 0x1f) && !vbus1 && !vbus3) {
	CPRINTS("TSU6721 cannot use manual mode: no VBUS or ID");
	return EC_ERROR_INVAL;
	}

	if (sel == TSU6721_MUX_AUTO) {
	tsu6721_write(TSU6721_REG_CONTROL, ctrl \| TSU6721_CTRL_AUTO);
	} else {
	tsu6721_write(TSU6721_REG_MANUAL1, sel);
	tsu6721_write(TSU6721_REG_CONTROL, ctrl & ~TSU6721_CTRL_AUTO);
	}

	return EC_SUCCESS;
	}

	void tsu6721_set_pins(int mask)
	{
	tsu6721_write(TSU6721_REG_MANUAL2, mask);
	}

	int tsu6721_init(void)
	{
	uint8_t settings;
	uint8_t dev_id = tsu6721_read(TSU6721_REG_DEV_ID);
	int res = 0;

	if ((dev_id != 0x0a) && (dev_id != 0x12)) {
	CPRINTS("TSU6721 invalid device ID 0x%02x", dev_id);
	return EC_ERROR_UNKNOWN;
	}

	/* set USB charger detection timeout to 600ms */
	settings = tsu6721_read(TSU6721_REG_TIMER);
	if (settings == 0xee)
	return EC_ERROR_UNKNOWN;
	settings = (settings & ~0x38);
	res \|= tsu6721_write(TSU6721_REG_TIMER, settings);

	res \|= tsu6721_set_interrupt_mask(TSU6721_INT_ATTACH \|
	TSU6721_INT_DETACH \|
	TSU6721_INT_ADC_CHANGE \|
	TSU6721_INT_VBUS);
	res \|= tsu6721_enable_interrupts();

	return res ? EC_ERROR_UNKNOWN : EC_SUCCESS;
	}
	/*
	* TODO(crosbug.com/p/23741): Using I2C early in the HOOK_INIT currently
	* triggers all sort of badness. Debug this before re-activating
	* initialization in HOOK_INIT.
	*/
	#if 0
	DECLARE_HOOK(HOOK_INIT, tsu6721_init, HOOK_PRIO_DEFAULT);
	#endif

	static void tsu6721_dump(void)
	{
	int i;
	uint8_t id = tsu6721_read(TSU6721_REG_ADC);
	uint8_t ctrl = tsu6721_read(TSU6721_REG_CONTROL);

	if (ctrl & TSU6721_CTRL_AUTO)
	ccprintf("Auto: %02x %02x %02x\n",
	tsu6721_read(TSU6721_REG_DEV_TYPE1),
	tsu6721_read(TSU6721_REG_DEV_TYPE2),
	tsu6721_read(TSU6721_REG_DEV_TYPE3));
	else
	ccprintf("Manual: %02x %02x\n",
	tsu6721_read(TSU6721_REG_MANUAL1),
	tsu6721_read(TSU6721_REG_MANUAL2));
	ccprintf("ID: 0x%02x\n", id);
	for (i = 1; i < 0x24; i++)
	ccprintf("%02x ", tsu6721_read(i));
	ccprintf("\n");
	}

	/*****************************************************************************/
	/* Console commands */
	#ifdef CONFIG_CMD_USBMUX
	static int command_usbmux(int argc, char **argv)
	{
	if (1 == argc) { /* dump all registers */
	tsu6721_dump();
	return EC_SUCCESS;
	} else if (2 == argc) {
	if (!strcasecmp(argv[1], "usb")) {
	tsu6721_mux(TSU6721_MUX_USB);
	} else if (!strcasecmp(argv[1], "uart1")) {
	tsu6721_mux(TSU6721_MUX_UART);
	} else if (!strcasecmp(argv[1], "uart2")) {
	tsu6721_mux(TSU6721_MUX_AUDIO);
	} else if (!strcasecmp(argv[1], "auto")) {
	tsu6721_mux(TSU6721_MUX_AUTO);
	} else { /* read one register */
	ccprintf("Invalid mux value: %s\n", argv[1]);
	return EC_ERROR_INVAL;
	}
	return EC_SUCCESS;
	}

	return EC_ERROR_INVAL;
	}
	DECLARE_CONSOLE_COMMAND(usbmux, command_usbmux,
	"[usb\|uart1\|uart2\|auto]",
	"TSU6721 USB mux control",
	NULL);
	#endif

	/*****************************************************************************/
	/* Host commands */

	static int usb_command_mux(struct host_cmd_handler_args *args)
	{
	const struct ec_params_usb_mux *p = args->params;

	if (system_is_locked())
	return EC_RES_ACCESS_DENIED;

	/* Safety check */
	if (p->mux != TSU6721_MUX_AUTO &&
	p->mux != TSU6721_MUX_USB &&
	p->mux != TSU6721_MUX_UART &&
	p->mux != TSU6721_MUX_AUDIO)
	return EC_RES_ERROR;

	if (tsu6721_mux(p->mux))
	return EC_RES_ERROR;
	return EC_RES_SUCCESS;
	}
	DECLARE_HOST_COMMAND(EC_CMD_USB_MUX, usb_command_mux, EC_VER_MASK(0));