Staging: initial version of the nvec driver

This is an implementation of a NVidia compliant embedded controller
protocol driver. It is used on some ARM-Tegra boards for device
communication.

Signed-off-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 468 insertions, 0 deletions

diff --git a/drivers/staging/nvec/nvec.c b/drivers/staging/nvec/nvec.c
new file mode 100644
index 000000000000..1a94364c48b5
--- /dev/null
+++ b/drivers/staging/nvec/nvec.c
@@ -0,0 +1,468 @@
+// #define DEBUG
+
+/* ToDo list (incomplete, unorderd)
+	- convert mouse, keyboard, and power to platform devices
+*/
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/serio.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/workqueue.h>
+#include <linux/clk.h>
+#include <mach/iomap.h>
+#include <mach/clk.h>
+#include <linux/semaphore.h>
+#include <linux/list.h>
+#include <linux/notifier.h>
+#include <linux/workqueue.h>
+#include <linux/platform_device.h>
+#include "nvec.h"
+
+static unsigned char EC_DISABLE_EVENT_REPORTING[] =	{'\x04','\x00','\x00'};
+static unsigned char EC_ENABLE_EVENT_REPORTING[] =	{'\x04','\x00','\x01'};
+static unsigned char EC_GET_FIRMWARE_VERSION[] =	{'\x07','\x15'};
+
+static struct nvec_chip *nvec_power_handle;
+
+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);
+
+static int nvec_status_notifier(struct notifier_block *nb, unsigned long event_type,
+				void *data)
+{
+	unsigned char *msg = (unsigned char *)data;
+	int i;
+
+	if(event_type != NVEC_CNTL)
+		return NOTIFY_DONE;
+
+	printk("unhandled msg type %ld, payload: ", event_type);
+	for (i = 0; i < msg[1]; i++)
+		printk("%0x ", msg[i+2]);
+	printk("\n");
+
+	return NOTIFY_OK;
+}
+
+void nvec_write_async(struct nvec_chip *nvec, unsigned char *data, short size)
+{
+	struct nvec_msg *msg = kzalloc(sizeof(struct nvec_msg), GFP_NOWAIT);
+
+	msg->data = kzalloc(size, GFP_NOWAIT);
+	msg->data[0] = size;
+	memcpy(msg->data + 1, data, size);
+	msg->size = size + 1;
+	msg->pos = 0;
+	INIT_LIST_HEAD(&msg->node);
+
+	list_add_tail(&msg->node, &nvec->tx_data);
+
+	gpio_set_value(nvec->gpio, 0);
+}
+EXPORT_SYMBOL(nvec_write_async);
+
+static void nvec_request_master(struct work_struct *work)
+{
+	struct nvec_chip *nvec = container_of(work, struct nvec_chip, tx_work);
+
+	if(!list_empty(&nvec->tx_data)) {
+		gpio_set_value(nvec->gpio, 0);
+	}
+}
+
+static int parse_msg(struct nvec_chip *nvec, struct nvec_msg *msg)
+{
+	int i;
+
+	if((msg->data[0] & 1<<7) == 0 && msg->data[3]) {
+		dev_err(nvec->dev, "ec responded %02x %02x %02x %02x\n", msg->data[0],
+			msg->data[1], msg->data[2], msg->data[3]);
+		return -EINVAL;
+	}
+
+	if ((msg->data[0] >> 7 ) == 1 && (msg->data[0] & 0x0f) == 5)
+	{
+		dev_warn(nvec->dev, "ec system event ");
+		for (i=0; i < msg->data[1]; i++)
+			dev_warn(nvec->dev, "%02x ", msg->data[2+i]);
+		dev_warn(nvec->dev, "\n");
+	}
+
+	atomic_notifier_call_chain(&nvec->notifier_list, msg->data[0] & 0x8f, msg->data);
+
+	return 0;
+}
+
+static struct nvec_msg *nvec_write_sync(struct nvec_chip *nvec, unsigned char *data, short size)
+{
+	down(&nvec->sync_write_mutex);
+
+	nvec->sync_write_pending = (data[1] << 8) + data[0];
+	nvec_write_async(nvec, data, size);
+
+	dev_dbg(nvec->dev, "nvec_sync_write: 0x%04x\n", nvec->sync_write_pending);
+	wait_for_completion(&nvec->sync_write);
+	dev_dbg(nvec->dev, "nvec_sync_write: pong!\n");
+
+	up(&nvec->sync_write_mutex);
+
+	return nvec->last_sync_msg;
+}
+
+/* RX worker */
+static void nvec_dispatch(struct work_struct *work)
+{
+	struct nvec_chip *nvec = container_of(work, struct nvec_chip, rx_work);
+	struct nvec_msg *msg;
+
+	while(!list_empty(&nvec->rx_data))
+	{
+		msg = list_first_entry(&nvec->rx_data, struct nvec_msg, node);
+		list_del_init(&msg->node);
+
+		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);
+			if((!msg) || (!msg->data))
+				dev_warn(nvec->dev, "attempt access zero pointer");
+			else {
+				kfree(msg->data);
+				kfree(msg);
+			}
+		}
+	}
+}
+
+static irqreturn_t i2c_interrupt(int irq, void *dev)
+{
+	unsigned long status;
+	unsigned long received;
+	unsigned char to_send;
+	struct nvec_msg *msg;
+	struct nvec_chip *nvec = (struct nvec_chip *)dev;
+	unsigned char *i2c_regs = nvec->i2c_regs;
+
+	status = readl(i2c_regs + I2C_SL_STATUS);
+
+	if(!(status & I2C_SL_IRQ))
+	{
+		dev_warn(nvec->dev, "nvec Spurious IRQ\n");
+		//Yup, handled. ahum.
+		goto handled;
+	}
+	if(status & END_TRANS && !(status & RCVD))
+	{
+		//Reenable IRQ only when even has been sent
+		//printk("Write sequence ended !\n");
+                //parse_msg(nvec);
+		nvec->state = NVEC_WAIT;
+		if(nvec->rx->size > 1)
+		{
+			list_add_tail(&nvec->rx->node, &nvec->rx_data);
+			schedule_work(&nvec->rx_work);
+		} else {
+			kfree(nvec->rx->data);
+			kfree(nvec->rx);
+		}
+		return IRQ_HANDLED;
+	} else if(status & RNW)
+	{
+		// Work around for AP20 New Slave Hw Bug. Give 1us extra.
+		// nvec/smbus/nvec_i2c_transport.c in NV`s crap for reference
+		if(status & RCVD)
+			udelay(3);
+
+		if(status & RCVD)
+		{
+			nvec->state = NVEC_WRITE;
+			//Master wants something from us. New communication
+//			dev_dbg(nvec->dev, "New read comm!\n");
+		} else {
+			//Master wants something from us from a communication we've already started
+//			dev_dbg(nvec->dev, "Read comm cont !\n");
+		}
+		//if(msg_pos<msg_size) {
+		if(list_empty(&nvec->tx_data))
+		{
+			dev_err(nvec->dev, "nvec empty tx - sending no-op\n");
+			to_send = 0x8a;
+			nvec_write_async(nvec, "\x07\x02", 2);
+//			to_send = 0x01;
+		} else {
+			msg = list_first_entry(&nvec->tx_data, struct nvec_msg, node);
+			if(msg->pos < msg->size) {
+				to_send = msg->data[msg->pos];
+				msg->pos++;
+			} else {
+				dev_err(nvec->dev, "nvec crap! %d\n", msg->size);
+				to_send = 0x01;
+			}
+
+			if(msg->pos >= msg->size)
+			{
+				list_del_init(&msg->node);
+				kfree(msg->data);
+				kfree(msg);
+				schedule_work(&nvec->tx_work);
+				nvec->state = NVEC_WAIT;
+			}
+		}
+		writel(to_send, i2c_regs + I2C_SL_RCVD);
+
+		gpio_set_value(nvec->gpio, 1);
+
+		dev_dbg(nvec->dev, "nvec sent %x\n", to_send);
+
+		goto handled;
+	} else {
+		received = readl(i2c_regs + I2C_SL_RCVD);
+		//Workaround?
+		if(status & RCVD) {
+			writel(0, i2c_regs + I2C_SL_RCVD);
+			goto handled;
+		}
+
+		if (nvec->state == NVEC_WAIT)
+		{
+			nvec->state = NVEC_READ;
+			msg = kzalloc(sizeof(struct nvec_msg), GFP_NOWAIT);
+			msg->data = kzalloc(32, GFP_NOWAIT);
+			INIT_LIST_HEAD(&msg->node);
+			nvec->rx = msg;
+		} else
+			msg = nvec->rx;
+
+		BUG_ON(msg->pos > 32);
+
+		msg->data[msg->pos] = received;
+		msg->pos++;
+		msg->size = msg->pos;
+		dev_dbg(nvec->dev, "Got %02lx from Master (pos: %d)!\n", received, msg->pos);
+	}
+handled:
+	return IRQ_HANDLED;
+}
+
+static int __devinit nvec_add_subdev(struct nvec_chip *nvec, struct nvec_subdev *subdev)
+{
+	struct platform_device *pdev;
+
+	pdev = platform_device_alloc(subdev->name, subdev->id);
+	pdev->dev.parent = nvec->dev;
+	pdev->dev.platform_data = subdev->platform_data;
+
+	return platform_device_add(pdev);
+}
+
+static void tegra_init_i2c_slave(struct nvec_platform_data *pdata, unsigned char *i2c_regs,
+					struct clk *i2c_clk)
+{
+	u32 val;
+
+	clk_enable(i2c_clk);
+	tegra_periph_reset_assert(i2c_clk);
+	udelay(2);
+	tegra_periph_reset_deassert(i2c_clk);
+
+	writel(pdata->i2c_addr>>1, i2c_regs + I2C_SL_ADDR1);
+	writel(0, i2c_regs + I2C_SL_ADDR2);
+
+	writel(0x1E, i2c_regs + I2C_SL_DELAY_COUNT);
+	val = I2C_CNFG_NEW_MASTER_SFM | I2C_CNFG_PACKET_MODE_EN |
+		(0x2 << I2C_CNFG_DEBOUNCE_CNT_SHIFT);
+	writel(val, i2c_regs + I2C_CNFG);
+	writel(I2C_SL_NEWL, i2c_regs + I2C_SL_CNFG);
+
+	clk_disable(i2c_clk);
+}
+
+static void nvec_power_off(void)
+{
+	nvec_write_async(nvec_power_handle, EC_DISABLE_EVENT_REPORTING, 3);
+	nvec_write_async(nvec_power_handle, "\x04\x01", 2);
+}
+
+static int __devinit tegra_nvec_probe(struct platform_device *pdev)
+{
+	int err, i, ret;
+	struct clk *i2c_clk;
+	struct nvec_platform_data *pdata = pdev->dev.platform_data;
+	struct nvec_chip *nvec;
+	struct nvec_msg *msg;
+	unsigned char *i2c_regs;
+
+	nvec = kzalloc(sizeof(struct nvec_chip), GFP_KERNEL);
+	if(nvec == NULL) {
+		dev_err(&pdev->dev, "failed to reserve memory\n");
+		return -ENOMEM;
+	}
+	platform_set_drvdata(pdev, nvec);
+	nvec->dev = &pdev->dev;
+	nvec->gpio = pdata->gpio;
+	nvec->irq = pdata->irq;
+
+/*
+	i2c_clk=clk_get_sys(NULL, "i2c");
+	if(IS_ERR_OR_NULL(i2c_clk))
+		printk(KERN_ERR"No such clock tegra-i2c.2\n");
+	else
+		clk_enable(i2c_clk);
+*/
+	i2c_regs = ioremap(pdata->base, pdata->size);
+	if(!i2c_regs) {
+		dev_err(nvec->dev, "failed to ioremap registers\n");
+		goto failed;
+	}
+
+	nvec->i2c_regs = i2c_regs;
+
+	i2c_clk = clk_get_sys(pdata->clock, NULL);
+	if(IS_ERR_OR_NULL(i2c_clk)) {
+		dev_err(nvec->dev, "failed to get clock tegra-i2c.2\n");
+		goto failed;
+	}
+
+	tegra_init_i2c_slave(pdata, i2c_regs, i2c_clk);
+
+	err = request_irq(nvec->irq, i2c_interrupt, IRQF_DISABLED, "nvec", nvec);
+	if(err) {
+		dev_err(nvec->dev, "couldn't request irq");
+		goto failed;
+	}
+
+	clk_enable(i2c_clk);
+	clk_set_rate(i2c_clk, 8*80000);
+
+	/* Set the gpio to low when we've got something to say */
+	err = gpio_request(nvec->gpio, "nvec gpio");
+	if(err < 0)
+		dev_err(nvec->dev, "couldn't request gpio\n");
+
+	tegra_gpio_enable(nvec->gpio);
+	gpio_direction_output(nvec->gpio, 1);
+	gpio_set_value(nvec->gpio, 1);
+
+	ATOMIC_INIT_NOTIFIER_HEAD(&nvec->notifier_list);
+
+	init_completion(&nvec->sync_write);
+	sema_init(&nvec->sync_write_mutex, 1);
+	INIT_LIST_HEAD(&nvec->tx_data);
+	INIT_LIST_HEAD(&nvec->rx_data);
+	INIT_WORK(&nvec->rx_work, nvec_dispatch);
+	INIT_WORK(&nvec->tx_work, nvec_request_master);
+
+	/* enable event reporting */
+	nvec_write_async(nvec, EC_ENABLE_EVENT_REPORTING,
+				sizeof(EC_ENABLE_EVENT_REPORTING));
+
+	nvec_kbd_init(nvec);
+#ifdef CONFIG_SERIO_NVEC_PS2
+	nvec_ps2(nvec);
+#endif
+
+        /* setup subdevs */
+	for (i = 0; i < pdata->num_subdevs; i++) {
+		ret = nvec_add_subdev(nvec, &pdata->subdevs[i]);
+	}
+
+	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 */
+	msg = nvec_write_sync(nvec, EC_GET_FIRMWARE_VERSION,
+		sizeof(EC_GET_FIRMWARE_VERSION));
+
+	dev_warn(nvec->dev, "ec firmware version %02x.%02x.%02x / %02x\n",
+			msg->data[4], msg->data[5], msg->data[6], msg->data[7]);
+
+	kfree(msg->data);
+	kfree(msg);
+
+	/* unmute speakers? */
+	nvec_write_async(nvec, "\x0d\x10\x59\x94", 4);
+
+	/* enable lid switch event */
+	nvec_write_async(nvec, "\x01\x01\x01\x00\x00\x02\x00", 7);
+
+	/* enable power button event */
+	nvec_write_async(nvec, "\x01\x01\x01\x00\x00\x80\x00", 7);
+
+	return 0;
+
+failed:
+	kfree(nvec);
+	return -ENOMEM;
+}
+
+static int __devexit tegra_nvec_remove(struct platform_device *pdev)
+{
+	// TODO: unregister
+	return 0;
+}
+
+#ifdef CONFIG_PM
+
+static int tegra_nvec_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct nvec_chip *nvec = platform_get_drvdata(pdev);
+
+	dev_dbg(nvec->dev, "suspending\n");
+	nvec_write_async(nvec, EC_DISABLE_EVENT_REPORTING, 3);
+	nvec_write_async(nvec, "\x04\x02", 2);
+
+	return 0;
+}
+
+static int tegra_nvec_resume(struct platform_device *pdev) {
+
+	struct nvec_chip *nvec = platform_get_drvdata(pdev);
+
+	dev_dbg(nvec->dev, "resuming\n");
+	nvec_write_async(nvec, EC_ENABLE_EVENT_REPORTING, 3);
+
+	return 0;
+}
+
+#else
+#define tegra_nvec_suspend NULL
+#define tegra_nvec_resume NULL
+#endif
+
+static struct platform_driver nvec_device_driver =
+{
+	.probe = tegra_nvec_probe,
+	.remove = __devexit_p(tegra_nvec_remove),
+	.suspend = tegra_nvec_suspend,
+	.resume = tegra_nvec_resume,
+	.driver = {
+		.name = "nvec",
+		.owner = THIS_MODULE,
+	}
+};
+
+static int __init tegra_nvec_init(void)
+{
+	return platform_driver_register(&nvec_device_driver);
+}
+
+module_init(tegra_nvec_init);
+MODULE_ALIAS("platform:nvec");