blob: 2823cacde130937f33638604c89d1d077647df60 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* NVEC: NVIDIA compliant embedded controller interface
*
* Copyright (C) 2011 The AC100 Kernel Team <ac100@lists.lauchpad.net>
*
* Authors: Pierre-Hugues Husson <phhusson@free.fr>
* Ilya Petrov <ilya.muromec@gmail.com>
* Marc Dietrich <marvin24@gmx.de>
* Julian Andres Klode <jak@jak-linux.org>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/atomic.h>
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/list.h>
#include <linux/mfd/core.h>
#include <linux/mutex.h>
#include <linux/notifier.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include "nvec.h"
#define I2C_CNFG 0x00
#define I2C_CNFG_PACKET_MODE_EN BIT(10)
#define I2C_CNFG_NEW_MASTER_SFM BIT(11)
#define I2C_CNFG_DEBOUNCE_CNT_SHIFT 12
#define I2C_SL_CNFG 0x20
#define I2C_SL_NEWSL BIT(2)
#define I2C_SL_NACK BIT(1)
#define I2C_SL_RESP BIT(0)
#define I2C_SL_IRQ BIT(3)
#define END_TRANS BIT(4)
#define RCVD BIT(2)
#define RNW BIT(1)
#define I2C_SL_RCVD 0x24
#define I2C_SL_STATUS 0x28
#define I2C_SL_ADDR1 0x2c
#define I2C_SL_ADDR2 0x30
#define I2C_SL_DELAY_COUNT 0x3c
/**
* enum nvec_msg_category - Message categories for nvec_msg_alloc()
* @NVEC_MSG_RX: The message is an incoming message (from EC)
* @NVEC_MSG_TX: The message is an outgoing message (to EC)
*/
enum nvec_msg_category {
NVEC_MSG_RX,
NVEC_MSG_TX,
};
enum nvec_sleep_subcmds {
GLOBAL_EVENTS,
AP_PWR_DOWN,
AP_SUSPEND,
};
#define CNF_EVENT_REPORTING 0x01
#define GET_FIRMWARE_VERSION 0x15
#define LID_SWITCH BIT(1)
#define PWR_BUTTON BIT(15)
static struct nvec_chip *nvec_power_handle;
static const struct mfd_cell nvec_devices[] = {
{
.name = "nvec-kbd",
},
{
.name = "nvec-mouse",
},
{
.name = "nvec-power",
.id = 0,
},
{
.name = "nvec-power",
.id = 1,
},
{
.name = "nvec-paz00",
},
};
/**
* nvec_register_notifier - Register a notifier with nvec
* @nvec: A &struct nvec_chip
* @nb: The notifier block to register
* @events: Unused
*
* Registers a notifier with @nvec. The notifier will be added to an atomic
* notifier chain that is called for all received messages except those that
* correspond to a request initiated by nvec_write_sync().
*/
int nvec_register_notifier(struct nvec_chip *nvec, struct notifier_block *nb,
unsigned int events)
{
return atomic_notifier_chain_register(&nvec->notifier_list, nb);
}
EXPORT_SYMBOL_GPL(nvec_register_notifier);
/**
* nvec_unregister_notifier - Unregister a notifier with nvec
* @nvec: A &struct nvec_chip
* @nb: The notifier block to unregister
*
* Unregisters a notifier with @nvec. The notifier will be removed from the
* atomic notifier chain.
*/
int nvec_unregister_notifier(struct nvec_chip *nvec, struct notifier_block *nb)
{
return atomic_notifier_chain_unregister(&nvec->notifier_list, nb);
}
EXPORT_SYMBOL_GPL(nvec_unregister_notifier);
/*
* nvec_status_notifier - The final notifier
*
* Prints a message about control events not handled in the notifier
* chain.
*/
static int nvec_status_notifier(struct notifier_block *nb,
unsigned long event_type, void *data)
{
struct nvec_chip *nvec = container_of(nb, struct nvec_chip,
nvec_status_notifier);
unsigned char *msg = data;
if (event_type != NVEC_CNTL)
return NOTIFY_DONE;
dev_warn(nvec->dev, "unhandled msg type %ld\n", event_type);
print_hex_dump(KERN_WARNING, "payload: ", DUMP_PREFIX_NONE, 16, 1,
msg, msg[1] + 2, true);
return NOTIFY_OK;
}
/**
* nvec_msg_alloc:
* @nvec: A &struct nvec_chip
* @category: Pool category, see &enum nvec_msg_category
*
* Allocate a single &struct nvec_msg object from the message pool of
* @nvec. The result shall be passed to nvec_msg_free() if no longer
* used.
*
* Outgoing messages are placed in the upper 75% of the pool, keeping the
* lower 25% available for RX buffers only. The reason is to prevent a
* situation where all buffers are full and a message is thus endlessly
* retried because the response could never be processed.
*/
static struct nvec_msg *nvec_msg_alloc(struct nvec_chip *nvec,
enum nvec_msg_category category)
{
int i = (category == NVEC_MSG_TX) ? (NVEC_POOL_SIZE / 4) : 0;
for (; i < NVEC_POOL_SIZE; i++) {
if (atomic_xchg(&nvec->msg_pool[i].used, 1) == 0) {
dev_vdbg(nvec->dev, "INFO: Allocate %i\n", i);
return &nvec->msg_pool[i];
}
}
dev_err(nvec->dev, "could not allocate %s buffer\n",
(category == NVEC_MSG_TX) ? "TX" : "RX");
return NULL;
}
/**
* nvec_msg_free:
* @nvec: A &struct nvec_chip
* @msg: A message (must be allocated by nvec_msg_alloc() and belong to @nvec)
*
* Free the given message
*/
void nvec_msg_free(struct nvec_chip *nvec, struct nvec_msg *msg)
{
if (msg != &nvec->tx_scratch)
dev_vdbg(nvec->dev, "INFO: Free %ti\n", msg - nvec->msg_pool);
atomic_set(&msg->used, 0);
}
EXPORT_SYMBOL_GPL(nvec_msg_free);
/**
* nvec_msg_is_event - Return %true if @msg is an event
* @msg: A message
*/
static bool nvec_msg_is_event(struct nvec_msg *msg)
{
return msg->data[0] >> 7;
}
/**
* nvec_msg_size - Get the size of a message
* @msg: The message to get the size for
*
* This only works for received messages, not for outgoing messages.
*/
static size_t nvec_msg_size(struct nvec_msg *msg)
{
bool is_event = nvec_msg_is_event(msg);
int event_length = (msg->data[0] & 0x60) >> 5;
/* for variable size, payload size in byte 1 + count (1) + cmd (1) */
if (!is_event || event_length == NVEC_VAR_SIZE)
return (msg->pos || msg->size) ? (msg->data[1] + 2) : 0;
else if (event_length == NVEC_2BYTES)
return 2;
else if (event_length == NVEC_3BYTES)
return 3;
return 0;
}
/**
* nvec_gpio_set_value - Set the GPIO value
* @nvec: A &struct nvec_chip
* @value: The value to write (0 or 1)
*
* Like gpio_set_value(), but generating debugging information
*/
static void nvec_gpio_set_value(struct nvec_chip *nvec, int value)
{
dev_dbg(nvec->dev, "GPIO changed from %u to %u\n",
gpiod_get_value(nvec->gpiod), value);
gpiod_set_value(nvec->gpiod, value);
}
/**
* nvec_write_async - Asynchronously write a message to NVEC
* @nvec: An nvec_chip instance
* @data: The message data, starting with the request type
* @size: The size of @data
*
* Queue a single message to be transferred to the embedded controller
* and return immediately.
*
* Returns: 0 on success, a negative error code on failure. If a failure
* occurred, the nvec driver may print an error.
*/
int nvec_write_async(struct nvec_chip *nvec, const unsigned char *data,
short size)
{
struct nvec_msg *msg;
unsigned long flags;
msg = nvec_msg_alloc(nvec, NVEC_MSG_TX);
if (!msg)
return -ENOMEM;
msg->data[0] = size;
memcpy(msg->data + 1, data, size);
msg->size = size + 1;
spin_lock_irqsave(&nvec->tx_lock, flags);
list_add_tail(&msg->node, &nvec->tx_data);
spin_unlock_irqrestore(&nvec->tx_lock, flags);
schedule_work(&nvec->tx_work);
return 0;
}
EXPORT_SYMBOL(nvec_write_async);
/**
* nvec_write_sync - Write a message to nvec and read the response
* @nvec: An &struct nvec_chip
* @data: The data to write
* @size: The size of @data
* @msg: The response message received
*
* This is similar to nvec_write_async(), but waits for the
* request to be answered before returning. This function
* uses a mutex and can thus not be called from e.g.
* interrupt handlers.
*
* Returns: 0 on success, a negative error code on failure.
* The response message is returned in @msg. Shall be freed
* with nvec_msg_free() once no longer used.
*
*/
int nvec_write_sync(struct nvec_chip *nvec,
const unsigned char *data, short size,
struct nvec_msg **msg)
{
mutex_lock(&nvec->sync_write_mutex);
*msg = NULL;
nvec->sync_write_pending = (data[1] << 8) + data[0];
if (nvec_write_async(nvec, data, size) < 0) {
mutex_unlock(&nvec->sync_write_mutex);
return -ENOMEM;
}
dev_dbg(nvec->dev, "nvec_sync_write: 0x%04x\n",
nvec->sync_write_pending);
if (!(wait_for_completion_timeout(&nvec->sync_write,
msecs_to_jiffies(2000)))) {
dev_warn(nvec->dev,
"timeout waiting for sync write to complete\n");
mutex_unlock(&nvec->sync_write_mutex);
return -ETIMEDOUT;
}
dev_dbg(nvec->dev, "nvec_sync_write: pong!\n");
*msg = nvec->last_sync_msg;
mutex_unlock(&nvec->sync_write_mutex);
return 0;
}
EXPORT_SYMBOL(nvec_write_sync);
/**
* nvec_toggle_global_events - enables or disables global event reporting
* @nvec: nvec handle
* @state: true for enable, false for disable
*
* This switches on/off global event reports by the embedded controller.
*/
static void nvec_toggle_global_events(struct nvec_chip *nvec, bool state)
{
unsigned char global_events[] = { NVEC_SLEEP, GLOBAL_EVENTS, state };
nvec_write_async(nvec, global_events, 3);
}
/**
* nvec_event_mask - fill the command string with event bitfield
* @ev: points to event command string
* @mask: bit to insert into the event mask
*
* Configure event command expects a 32 bit bitfield which describes
* which events to enable. The bitfield has the following structure
* (from highest byte to lowest):
* system state bits 7-0
* system state bits 15-8
* oem system state bits 7-0
* oem system state bits 15-8
*/
static void nvec_event_mask(char *ev, u32 mask)
{
ev[3] = mask >> 16 & 0xff;
ev[4] = mask >> 24 & 0xff;
ev[5] = mask >> 0 & 0xff;
ev[6] = mask >> 8 & 0xff;
}
/**
* nvec_request_master - Process outgoing messages
* @work: A &struct work_struct (the tx_worker member of &struct nvec_chip)
*
* Processes all outgoing requests by sending the request and awaiting the
* response, then continuing with the next request. Once a request has a
* matching response, it will be freed and removed from the list.
*/
static void nvec_request_master(struct work_struct *work)
{
struct nvec_chip *nvec = container_of(work, struct nvec_chip, tx_work);
unsigned long flags;
long err;
struct nvec_msg *msg;
spin_lock_irqsave(&nvec->tx_lock, flags);
while (!list_empty(&nvec->tx_data)) {
msg = list_first_entry(&nvec->tx_data, struct nvec_msg, node);
spin_unlock_irqrestore(&nvec->tx_lock, flags);
nvec_gpio_set_value(nvec, 0);
err = wait_for_completion_interruptible_timeout(&nvec->ec_transfer,
msecs_to_jiffies(5000));
if (err == 0) {
dev_warn(nvec->dev, "timeout waiting for ec transfer\n");
nvec_gpio_set_value(nvec, 1);
msg->pos = 0;
}
spin_lock_irqsave(&nvec->tx_lock, flags);
if (err > 0) {
list_del_init(&msg->node);
nvec_msg_free(nvec, msg);
}
}
spin_unlock_irqrestore(&nvec->tx_lock, flags);
}
/**
* parse_msg - Print some information and call the notifiers on an RX message
* @nvec: A &struct nvec_chip
* @msg: A message received by @nvec
*
* Paarse some pieces of the message and then call the chain of notifiers
* registered via nvec_register_notifier.
*/
static int parse_msg(struct nvec_chip *nvec, struct nvec_msg *msg)
{
if ((msg->data[0] & 1 << 7) == 0 && msg->data[3]) {
dev_err(nvec->dev, "ec responded %*ph\n", 4, msg->data);
return -EINVAL;
}
if ((msg->data[0] >> 7) == 1 && (msg->data[0] & 0x0f) == 5)
print_hex_dump(KERN_WARNING, "ec system event ",
DUMP_PREFIX_NONE, 16, 1, msg->data,
msg->data[1] + 2, true);
atomic_notifier_call_chain(&nvec->notifier_list, msg->data[0] & 0x8f,
msg->data);
return 0;
}
/**
* nvec_dispatch - Process messages received from the EC
* @work: A &struct work_struct (the tx_worker member of &struct nvec_chip)
*
* Process messages previously received from the EC and put into the RX
* queue of the &struct nvec_chip instance associated with @work.
*/
static void nvec_dispatch(struct work_struct *work)
{
struct nvec_chip *nvec = container_of(work, struct nvec_chip, rx_work);
unsigned long flags;
struct nvec_msg *msg;
spin_lock_irqsave(&nvec->rx_lock, flags);
while (!list_empty(&nvec->rx_data)) {
msg = list_first_entry(&nvec->rx_data, struct nvec_msg, node);
list_del_init(&msg->node);
spin_unlock_irqrestore(&nvec->rx_lock, flags);
if (nvec->sync_write_pending ==
(msg->data[2] << 8) + msg->data[0]) {
dev_dbg(nvec->dev, "sync write completed!\n");
nvec->sync_write_pending = 0;
nvec->last_sync_msg = msg;
complete(&nvec->sync_write);
} else {
parse_msg(nvec, msg);
nvec_msg_free(nvec, msg);
}
spin_lock_irqsave(&nvec->rx_lock, flags);
}
spin_unlock_irqrestore(&nvec->rx_lock, flags);
}
/**
* nvec_tx_completed - Complete the current transfer
* @nvec: A &struct nvec_chip
*
* This is called when we have received an END_TRANS on a TX transfer.
*/
static void nvec_tx_completed(struct nvec_chip *nvec)
{
/* We got an END_TRANS, let's skip this, maybe there's an event */
if (nvec->tx->pos != nvec->tx->size) {
dev_err(nvec->dev, "premature END_TRANS, resending\n");
nvec->tx->pos = 0;
nvec_gpio_set_value(nvec, 0);
} else {
nvec->state = 0;
}
}
/**
* nvec_rx_completed - Complete the current transfer
* @nvec: A &struct nvec_chip
*
* This is called when we have received an END_TRANS on a RX transfer.
*/
static void nvec_rx_completed(struct nvec_chip *nvec)
{
if (nvec->rx->pos != nvec_msg_size(nvec->rx)) {
dev_err(nvec->dev, "RX incomplete: Expected %u bytes, got %u\n",
(uint)nvec_msg_size(nvec->rx),
(uint)nvec->rx->pos);
nvec_msg_free(nvec, nvec->rx);
nvec->state = 0;
/* Battery quirk - Often incomplete, and likes to crash */
if (nvec->rx->data[0] == NVEC_BAT)
complete(&nvec->ec_transfer);
return;
}
spin_lock(&nvec->rx_lock);
/*
* Add the received data to the work list and move the ring buffer
* pointer to the next entry.
*/
list_add_tail(&nvec->rx->node, &nvec->rx_data);
spin_unlock(&nvec->rx_lock);
nvec->state = 0;
if (!nvec_msg_is_event(nvec->rx))
complete(&nvec->ec_transfer);
schedule_work(&nvec->rx_work);
}
/**
* nvec_invalid_flags - Send an error message about invalid flags and jump
* @nvec: The nvec device
* @status: The status flags
* @reset: Whether we shall jump to state 0.
*/
static void nvec_invalid_flags(struct nvec_chip *nvec, unsigned int status,
bool reset)
{
dev_err(nvec->dev, "unexpected status flags 0x%02x during state %i\n",
status, nvec->state);
if (reset)
nvec->state = 0;
}
/**
* nvec_tx_set - Set the message to transfer (nvec->tx)
* @nvec: A &struct nvec_chip
*
* Gets the first entry from the tx_data list of @nvec and sets the
* tx member to it. If the tx_data list is empty, this uses the
* tx_scratch message to send a no operation message.
*/
static void nvec_tx_set(struct nvec_chip *nvec)
{
spin_lock(&nvec->tx_lock);
if (list_empty(&nvec->tx_data)) {
dev_err(nvec->dev, "empty tx - sending no-op\n");
memcpy(nvec->tx_scratch.data, "\x02\x07\x02", 3);
nvec->tx_scratch.size = 3;
nvec->tx_scratch.pos = 0;
nvec->tx = &nvec->tx_scratch;
list_add_tail(&nvec->tx->node, &nvec->tx_data);
} else {
nvec->tx = list_first_entry(&nvec->tx_data, struct nvec_msg,
node);
nvec->tx->pos = 0;
}
spin_unlock(&nvec->tx_lock);
dev_dbg(nvec->dev, "Sending message of length %u, command 0x%x\n",
(uint)nvec->tx->size, nvec->tx->data[1]);
}
/**
* nvec_interrupt - Interrupt handler
* @irq: The IRQ
* @dev: The nvec device
*
* Interrupt handler that fills our RX buffers and empties our TX
* buffers. This uses a finite state machine with ridiculous amounts
* of error checking, in order to be fairly reliable.
*/
static irqreturn_t nvec_interrupt(int irq, void *dev)
{
unsigned long status;
unsigned int received = 0;
unsigned char to_send = 0xff;
const unsigned long irq_mask = I2C_SL_IRQ | END_TRANS | RCVD | RNW;
struct nvec_chip *nvec = dev;
unsigned int state = nvec->state;
status = readl(nvec->base + I2C_SL_STATUS);
/* Filter out some errors */
if ((status & irq_mask) == 0 && (status & ~irq_mask) != 0) {
dev_err(nvec->dev, "unexpected irq mask %lx\n", status);
return IRQ_HANDLED;
}
if ((status & I2C_SL_IRQ) == 0) {
dev_err(nvec->dev, "Spurious IRQ\n");
return IRQ_HANDLED;
}
/* The EC did not request a read, so it send us something, read it */
if ((status & RNW) == 0) {
received = readl(nvec->base + I2C_SL_RCVD);
if (status & RCVD)
writel(0, nvec->base + I2C_SL_RCVD);
}
if (status == (I2C_SL_IRQ | RCVD))
nvec->state = 0;
switch (nvec->state) {
case 0: /* Verify that its a transfer start, the rest later */
if (status != (I2C_SL_IRQ | RCVD))
nvec_invalid_flags(nvec, status, false);
break;
case 1: /* command byte */
if (status != I2C_SL_IRQ) {
nvec_invalid_flags(nvec, status, true);
} else {
nvec->rx = nvec_msg_alloc(nvec, NVEC_MSG_RX);
/* Should not happen in a normal world */
if (unlikely(!nvec->rx)) {
nvec->state = 0;
break;
}
nvec->rx->data[0] = received;
nvec->rx->pos = 1;
nvec->state = 2;
}
break;
case 2: /* first byte after command */
if (status == (I2C_SL_IRQ | RNW | RCVD)) {
udelay(33);
if (nvec->rx->data[0] != 0x01) {
dev_err(nvec->dev,
"Read without prior read command\n");
nvec->state = 0;
break;
}
nvec_msg_free(nvec, nvec->rx);
nvec->state = 3;
nvec_tx_set(nvec);
to_send = nvec->tx->data[0];
nvec->tx->pos = 1;
} else if (status == (I2C_SL_IRQ)) {
nvec->rx->data[1] = received;
nvec->rx->pos = 2;
nvec->state = 4;
} else {
nvec_invalid_flags(nvec, status, true);
}
break;
case 3: /* EC does a block read, we transmit data */
if (status & END_TRANS) {
nvec_tx_completed(nvec);
} else if ((status & RNW) == 0 || (status & RCVD)) {
nvec_invalid_flags(nvec, status, true);
} else if (nvec->tx && nvec->tx->pos < nvec->tx->size) {
to_send = nvec->tx->data[nvec->tx->pos++];
} else {
dev_err(nvec->dev,
"tx buffer underflow on %p (%u > %u)\n",
nvec->tx,
(uint)(nvec->tx ? nvec->tx->pos : 0),
(uint)(nvec->tx ? nvec->tx->size : 0));
nvec->state = 0;
}
break;
case 4: /* EC does some write, we read the data */
if ((status & (END_TRANS | RNW)) == END_TRANS)
nvec_rx_completed(nvec);
else if (status & (RNW | RCVD))
nvec_invalid_flags(nvec, status, true);
else if (nvec->rx && nvec->rx->pos < NVEC_MSG_SIZE)
nvec->rx->data[nvec->rx->pos++] = received;
else
dev_err(nvec->dev,
"RX buffer overflow on %p: Trying to write byte %u of %u\n",
nvec->rx, nvec->rx ? nvec->rx->pos : 0,
NVEC_MSG_SIZE);
break;
default:
nvec->state = 0;
}
/* If we are told that a new transfer starts, verify it */
if ((status & (RCVD | RNW)) == RCVD) {
if (received != nvec->i2c_addr)
dev_err(nvec->dev,
"received address 0x%02x, expected 0x%02x\n",
received, nvec->i2c_addr);
nvec->state = 1;
}
/* Send data if requested, but not on end of transmission */
if ((status & (RNW | END_TRANS)) == RNW)
writel(to_send, nvec->base + I2C_SL_RCVD);
/* If we have send the first byte */
if (status == (I2C_SL_IRQ | RNW | RCVD))
nvec_gpio_set_value(nvec, 1);
dev_dbg(nvec->dev,
"Handled: %s 0x%02x, %s 0x%02x in state %u [%s%s%s]\n",
(status & RNW) == 0 ? "received" : "R=",
received,
(status & (RNW | END_TRANS)) ? "sent" : "S=",
to_send,
state,
status & END_TRANS ? " END_TRANS" : "",
status & RCVD ? " RCVD" : "",
status & RNW ? " RNW" : "");
/*
* TODO: A correct fix needs to be found for this.
*
* We experience less incomplete messages with this delay than without
* it, but we don't know why. Help is appreciated.
*/
udelay(100);
return IRQ_HANDLED;
}
static void tegra_init_i2c_slave(struct nvec_chip *nvec)
{
u32 val;
clk_prepare_enable(nvec->i2c_clk);
reset_control_assert(nvec->rst);
udelay(2);
reset_control_deassert(nvec->rst);
val = I2C_CNFG_NEW_MASTER_SFM | I2C_CNFG_PACKET_MODE_EN |
(0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT);
writel(val, nvec->base + I2C_CNFG);
clk_set_rate(nvec->i2c_clk, 8 * 80000);
writel(I2C_SL_NEWSL, nvec->base + I2C_SL_CNFG);
writel(0x1E, nvec->base + I2C_SL_DELAY_COUNT);
writel(nvec->i2c_addr >> 1, nvec->base + I2C_SL_ADDR1);
writel(0, nvec->base + I2C_SL_ADDR2);
enable_irq(nvec->irq);
}
#ifdef CONFIG_PM_SLEEP
static void nvec_disable_i2c_slave(struct nvec_chip *nvec)
{
disable_irq(nvec->irq);
writel(I2C_SL_NEWSL | I2C_SL_NACK, nvec->base + I2C_SL_CNFG);
clk_disable_unprepare(nvec->i2c_clk);
}
#endif
static void nvec_power_off(void)
{
char ap_pwr_down[] = { NVEC_SLEEP, AP_PWR_DOWN };
nvec_toggle_global_events(nvec_power_handle, false);
nvec_write_async(nvec_power_handle, ap_pwr_down, 2);
}
static int tegra_nvec_probe(struct platform_device *pdev)
{
int err, ret;
struct clk *i2c_clk;
struct device *dev = &pdev->dev;
struct nvec_chip *nvec;
struct nvec_msg *msg;
void __iomem *base;
char get_firmware_version[] = { NVEC_CNTL, GET_FIRMWARE_VERSION },
unmute_speakers[] = { NVEC_OEM0, 0x10, 0x59, 0x95 },
enable_event[7] = { NVEC_SYS, CNF_EVENT_REPORTING, true };
if (!dev->of_node) {
dev_err(dev, "must be instantiated using device tree\n");
return -ENODEV;
}
nvec = devm_kzalloc(dev, sizeof(struct nvec_chip), GFP_KERNEL);
if (!nvec)
return -ENOMEM;
platform_set_drvdata(pdev, nvec);
nvec->dev = dev;
if (of_property_read_u32(dev->of_node, "slave-addr", &nvec->i2c_addr)) {
dev_err(dev, "no i2c address specified");
return -ENODEV;
}
base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(base))
return PTR_ERR(base);
nvec->irq = platform_get_irq(pdev, 0);
if (nvec->irq < 0)
return -ENODEV;
i2c_clk = devm_clk_get(dev, "div-clk");
if (IS_ERR(i2c_clk)) {
dev_err(dev, "failed to get controller clock\n");
return -ENODEV;
}
nvec->rst = devm_reset_control_get_exclusive(dev, "i2c");
if (IS_ERR(nvec->rst)) {
dev_err(dev, "failed to get controller reset\n");
return PTR_ERR(nvec->rst);
}
nvec->base = base;
nvec->i2c_clk = i2c_clk;
nvec->rx = &nvec->msg_pool[0];
ATOMIC_INIT_NOTIFIER_HEAD(&nvec->notifier_list);
init_completion(&nvec->sync_write);
init_completion(&nvec->ec_transfer);
mutex_init(&nvec->sync_write_mutex);
spin_lock_init(&nvec->tx_lock);
spin_lock_init(&nvec->rx_lock);
INIT_LIST_HEAD(&nvec->rx_data);
INIT_LIST_HEAD(&nvec->tx_data);
INIT_WORK(&nvec->rx_work, nvec_dispatch);
INIT_WORK(&nvec->tx_work, nvec_request_master);
nvec->gpiod = devm_gpiod_get(dev, "request", GPIOD_OUT_HIGH);
if (IS_ERR(nvec->gpiod)) {
dev_err(dev, "couldn't request gpio\n");
return PTR_ERR(nvec->gpiod);
}
err = devm_request_irq(dev, nvec->irq, nvec_interrupt, 0,
"nvec", nvec);
if (err) {
dev_err(dev, "couldn't request irq\n");
return -ENODEV;
}
disable_irq(nvec->irq);
tegra_init_i2c_slave(nvec);
/* enable event reporting */
nvec_toggle_global_events(nvec, true);
nvec->nvec_status_notifier.notifier_call = nvec_status_notifier;
nvec_register_notifier(nvec, &nvec->nvec_status_notifier, 0);
nvec_power_handle = nvec;
pm_power_off = nvec_power_off;
/* Get Firmware Version */
err = nvec_write_sync(nvec, get_firmware_version, 2, &msg);
if (!err) {
dev_warn(dev,
"ec firmware version %02x.%02x.%02x / %02x\n",
msg->data[4], msg->data[5],
msg->data[6], msg->data[7]);
nvec_msg_free(nvec, msg);
}
ret = mfd_add_devices(dev, 0, nvec_devices,
ARRAY_SIZE(nvec_devices), NULL, 0, NULL);
if (ret)
dev_err(dev, "error adding subdevices\n");
/* unmute speakers? */
nvec_write_async(nvec, unmute_speakers, 4);
/* enable lid switch event */
nvec_event_mask(enable_event, LID_SWITCH);
nvec_write_async(nvec, enable_event, 7);
/* enable power button event */
nvec_event_mask(enable_event, PWR_BUTTON);
nvec_write_async(nvec, enable_event, 7);
return 0;
}
static void tegra_nvec_remove(struct platform_device *pdev)
{
struct nvec_chip *nvec = platform_get_drvdata(pdev);
nvec_toggle_global_events(nvec, false);
mfd_remove_devices(nvec->dev);
nvec_unregister_notifier(nvec, &nvec->nvec_status_notifier);
cancel_work_sync(&nvec->rx_work);
cancel_work_sync(&nvec->tx_work);
/* FIXME: needs check whether nvec is responsible for power off */
pm_power_off = NULL;
}
#ifdef CONFIG_PM_SLEEP
static int nvec_suspend(struct device *dev)
{
int err;
struct nvec_chip *nvec = dev_get_drvdata(dev);
struct nvec_msg *msg;
char ap_suspend[] = { NVEC_SLEEP, AP_SUSPEND };
dev_dbg(nvec->dev, "suspending\n");
/* keep these sync or you'll break suspend */
nvec_toggle_global_events(nvec, false);
err = nvec_write_sync(nvec, ap_suspend, sizeof(ap_suspend), &msg);
if (!err)
nvec_msg_free(nvec, msg);
nvec_disable_i2c_slave(nvec);
return 0;
}
static int nvec_resume(struct device *dev)
{
struct nvec_chip *nvec = dev_get_drvdata(dev);
dev_dbg(nvec->dev, "resuming\n");
tegra_init_i2c_slave(nvec);
nvec_toggle_global_events(nvec, true);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(nvec_pm_ops, nvec_suspend, nvec_resume);
/* Match table for of_platform binding */
static const struct of_device_id nvidia_nvec_of_match[] = {
{ .compatible = "nvidia,nvec", },
{},
};
MODULE_DEVICE_TABLE(of, nvidia_nvec_of_match);
static struct platform_driver nvec_device_driver = {
.probe = tegra_nvec_probe,
.remove_new = tegra_nvec_remove,
.driver = {
.name = "nvec",
.pm = &nvec_pm_ops,
.of_match_table = nvidia_nvec_of_match,
}
};
module_platform_driver(nvec_device_driver);
MODULE_ALIAS("platform:nvec");
MODULE_DESCRIPTION("NVIDIA compliant embedded controller interface");
MODULE_AUTHOR("Marc Dietrich <marvin24@gmx.de>");
MODULE_LICENSE("GPL");