drivers/mfd/ipaq-micro.c - kernel/msm-4.9 - Gitiles

 /*
  * Compaq iPAQ h3xxx Atmel microcontroller companion support
  *
  * This is an Atmel AT90LS8535 with a special flashed-in firmware that
  * implements the special protocol used by this driver.
  *
  * based on previous kernel 2.4 version by Andrew Christian
  * Author : Alessandro Gardich <gremlin@gremlin.it>
  * Author : Dmitry Artamonow <mad_soft@inbox.ru>
  * Author : Linus Walleij <linus.walleij@linaro.org>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/pm.h>
 #include <linux/delay.h>
 #include <linux/device.h>
 #include <linux/platform_device.h>
 #include <linux/io.h>
 #include <linux/mfd/core.h>
 #include <linux/mfd/ipaq-micro.h>
 #include <linux/string.h>
 #include <linux/random.h>
 #include <linux/slab.h>
 #include <linux/list.h>

 #include <mach/hardware.h>

 static void ipaq_micro_trigger_tx(struct ipaq_micro *micro)
 {
 	struct ipaq_micro_txdev *tx = &micro->tx;
 	struct ipaq_micro_msg *msg = micro->msg;
 	int i, bp;
 	u8 checksum;
 	u32 val;

 	bp = 0;
 	tx->buf[bp++] = CHAR_SOF;

 	checksum = ((msg->id & 0x0f) << 4) | (msg->tx_len & 0x0f);
 	tx->buf[bp++] = checksum;

 	for (i = 0; i < msg->tx_len; i++) {
 		tx->buf[bp++] = msg->tx_data[i];
 		checksum += msg->tx_data[i];
 	}

 	tx->buf[bp++] = checksum;
 	tx->len = bp;
 	tx->index = 0;
 	print_hex_dump_debug("data: ", DUMP_PREFIX_OFFSET, 16, 1,
 			     tx->buf, tx->len, true);

 	/* Enable interrupt */
 	val = readl(micro->base + UTCR3);
 	val |= UTCR3_TIE;
 	writel(val, micro->base + UTCR3);
 }

 int ipaq_micro_tx_msg(struct ipaq_micro *micro, struct ipaq_micro_msg *msg)
 {
 	unsigned long flags;

 	dev_dbg(micro->dev, "TX msg: %02x, %d bytes\n", msg->id, msg->tx_len);

 	spin_lock_irqsave(&micro->lock, flags);
 	if (micro->msg) {
 		list_add_tail(&msg->node, &micro->queue);
 		spin_unlock_irqrestore(&micro->lock, flags);
 		return 0;
 	}
 	micro->msg = msg;
 	ipaq_micro_trigger_tx(micro);
 	spin_unlock_irqrestore(&micro->lock, flags);
 	return 0;
 }
 EXPORT_SYMBOL(ipaq_micro_tx_msg);

 static void micro_rx_msg(struct ipaq_micro *micro, u8 id, int len, u8 *data)
 {
 	int i;

 	dev_dbg(micro->dev, "RX msg: %02x, %d bytes\n", id, len);

 	spin_lock(&micro->lock);
 	switch (id) {
 	case MSG_VERSION:
 	case MSG_EEPROM_READ:
 	case MSG_EEPROM_WRITE:
 	case MSG_BACKLIGHT:
 	case MSG_NOTIFY_LED:
 	case MSG_THERMAL_SENSOR:
 	case MSG_BATTERY:
 		/* Handle synchronous messages */
 		if (micro->msg && micro->msg->id == id) {
 			struct ipaq_micro_msg *msg = micro->msg;

 			memcpy(msg->rx_data, data, len);
 			msg->rx_len = len;
 			complete(&micro->msg->ack);
 			if (!list_empty(&micro->queue)) {
 				micro->msg = list_entry(micro->queue.next,
 							struct ipaq_micro_msg,
 							node);
 				list_del_init(&micro->msg->node);
 				ipaq_micro_trigger_tx(micro);
 			} else
 				micro->msg = NULL;
 			dev_dbg(micro->dev, "OK RX message 0x%02x\n", id);
 		} else {
 			dev_err(micro->dev,
 				"out of band RX message 0x%02x\n", id);
 			if (!micro->msg)
 				dev_info(micro->dev, "no message queued\n");
 			else
 				dev_info(micro->dev, "expected message %02x\n",
 					 micro->msg->id);
 		}
 		break;
 	case MSG_KEYBOARD:
 		if (micro->key)
 			micro->key(micro->key_data, len, data);
 		else
 			dev_dbg(micro->dev, "key message ignored, no handle\n");
 		break;
 	case MSG_TOUCHSCREEN:
 		if (micro->ts)
 			micro->ts(micro->ts_data, len, data);
 		else
 			dev_dbg(micro->dev, "touchscreen message ignored, no handle\n");
 		break;
 	default:
 		dev_err(micro->dev,
 			"unknown msg %d [%d] ", id, len);
 		for (i = 0; i < len; ++i)
 			pr_cont("0x%02x ", data[i]);
 		pr_cont("\n");
 	}
 	spin_unlock(&micro->lock);
 }

 static void micro_process_char(struct ipaq_micro *micro, u8 ch)
 {
 	struct ipaq_micro_rxdev *rx = &micro->rx;

 	switch (rx->state) {
 	case STATE_SOF:	/* Looking for SOF */
 		if (ch == CHAR_SOF)
 			rx->state = STATE_ID; /* Next byte is the id and len */
 		break;
 	case STATE_ID: /* Looking for id and len byte */
 		rx->id = (ch & 0xf0) >> 4;
 		rx->len = (ch & 0x0f);
 		rx->index = 0;
 		rx->chksum = ch;
 		rx->state = (rx->len > 0) ? STATE_DATA : STATE_CHKSUM;
 		break;
 	case STATE_DATA: /* Looking for 'len' data bytes */
 		rx->chksum += ch;
 		rx->buf[rx->index] = ch;
 		if (++rx->index == rx->len)
 			rx->state = STATE_CHKSUM;
 		break;
 	case STATE_CHKSUM: /* Looking for the checksum */
 		if (ch == rx->chksum)
 			micro_rx_msg(micro, rx->id, rx->len, rx->buf);
 		rx->state = STATE_SOF;
 		break;
 	}
 }

 static void micro_rx_chars(struct ipaq_micro *micro)
 {
 	u32 status, ch;

 	while ((status = readl(micro->base + UTSR1)) & UTSR1_RNE) {
 		ch = readl(micro->base + UTDR);
 		if (status & UTSR1_PRE)
 			dev_err(micro->dev, "rx: parity error\n");
 		else if (status & UTSR1_FRE)
 			dev_err(micro->dev, "rx: framing error\n");
 		else if (status & UTSR1_ROR)
 			dev_err(micro->dev, "rx: overrun error\n");
 		micro_process_char(micro, ch);
 	}
 }

 static void ipaq_micro_get_version(struct ipaq_micro *micro)
 {
 	struct ipaq_micro_msg msg = {
 		.id = MSG_VERSION,
 	};

 	ipaq_micro_tx_msg_sync(micro, &msg);
 	if (msg.rx_len == 4) {
 		memcpy(micro->version, msg.rx_data, 4);
 		micro->version[4] = '\0';
 	} else if (msg.rx_len == 9) {
 		memcpy(micro->version, msg.rx_data, 4);
 		micro->version[4] = '\0';
 		/* Bytes 4-7 are "pack", byte 8 is "boot type" */
 	} else {
 		dev_err(micro->dev,
 			"illegal version message %d bytes\n", msg.rx_len);
 	}
 }

 static void ipaq_micro_eeprom_read(struct ipaq_micro *micro,
 				   u8 address, u8 len, u8 *data)
 {
 	struct ipaq_micro_msg msg = {
 		.id = MSG_EEPROM_READ,
 	};
 	u8 i;

 	for (i = 0; i < len; i++) {
 		msg.tx_data[0] = address + i;
 		msg.tx_data[1] = 1;
 		msg.tx_len = 2;
 		ipaq_micro_tx_msg_sync(micro, &msg);
 		memcpy(data + (i * 2), msg.rx_data, 2);
 	}
 }

 static char *ipaq_micro_str(u8 *wchar, u8 len)
 {
 	char retstr[256];
 	u8 i;

 	for (i = 0; i < len / 2; i++)
 		retstr[i] = wchar[i * 2];
 	return kstrdup(retstr, GFP_KERNEL);
 }

 static u16 ipaq_micro_to_u16(u8 *data)
 {
 	return data[1] << 8 | data[0];
 }

 static void __init ipaq_micro_eeprom_dump(struct ipaq_micro *micro)
 {
 	u8 dump[256];
 	char *str;

 	ipaq_micro_eeprom_read(micro, 0, 128, dump);
 	str = ipaq_micro_str(dump, 10);
 	if (str) {
 		dev_info(micro->dev, "HW version %s\n", str);
 		kfree(str);
 	}
 	str = ipaq_micro_str(dump+10, 40);
 	if (str) {
 		dev_info(micro->dev, "serial number: %s\n", str);
 		/* Feed the random pool with this */
 		add_device_randomness(str, strlen(str));
 		kfree(str);
 	}
 	str = ipaq_micro_str(dump+50, 20);
 	if (str) {
 		dev_info(micro->dev, "module ID: %s\n", str);
 		kfree(str);
 	}
 	str = ipaq_micro_str(dump+70, 10);
 	if (str) {
 		dev_info(micro->dev, "product revision: %s\n", str);
 		kfree(str);
 	}
 	dev_info(micro->dev, "product ID: %u\n", ipaq_micro_to_u16(dump+80));
 	dev_info(micro->dev, "frame rate: %u fps\n",
 		 ipaq_micro_to_u16(dump+82));
 	dev_info(micro->dev, "page mode: %u\n", ipaq_micro_to_u16(dump+84));
 	dev_info(micro->dev, "country ID: %u\n", ipaq_micro_to_u16(dump+86));
 	dev_info(micro->dev, "color display: %s\n",
 		 ipaq_micro_to_u16(dump+88) ? "yes" : "no");
 	dev_info(micro->dev, "ROM size: %u MiB\n", ipaq_micro_to_u16(dump+90));
 	dev_info(micro->dev, "RAM size: %u KiB\n", ipaq_micro_to_u16(dump+92));
 	dev_info(micro->dev, "screen: %u x %u\n",
 		 ipaq_micro_to_u16(dump+94), ipaq_micro_to_u16(dump+96));
 	print_hex_dump_debug("eeprom: ", DUMP_PREFIX_OFFSET, 16, 1,
 			     dump, 256, true);

 }

 static void micro_tx_chars(struct ipaq_micro *micro)
 {
 	struct ipaq_micro_txdev *tx = &micro->tx;
 	u32 val;

 	while ((tx->index < tx->len) &&
 	       (readl(micro->base + UTSR1) & UTSR1_TNF)) {
 		writel(tx->buf[tx->index], micro->base + UTDR);
 		tx->index++;
 	}

 	/* Stop interrupts */
 	val = readl(micro->base + UTCR3);
 	val &= ~UTCR3_TIE;
 	writel(val, micro->base + UTCR3);
 }

 static void micro_reset_comm(struct ipaq_micro *micro)
 {
 	struct ipaq_micro_rxdev *rx = &micro->rx;
 	u32 val;

 	if (micro->msg)
 		complete(&micro->msg->ack);

 	/* Initialize Serial channel protocol frame */
 	rx->state = STATE_SOF;  /* Reset the state machine */

 	/* Set up interrupts */
 	writel(0x01, micro->sdlc + 0x0); /* Select UART mode */

 	/* Clean up CR3 */
 	writel(0x0, micro->base + UTCR3);

 	/* Format: 8N1 */
 	writel(UTCR0_8BitData | UTCR0_1StpBit, micro->base + UTCR0);

 	/* Baud rate: 115200 */
 	writel(0x0, micro->base + UTCR1);
 	writel(0x1, micro->base + UTCR2);

 	/* Clear SR0 */
 	writel(0xff, micro->base + UTSR0);

 	/* Enable RX int, disable TX int */
 	writel(UTCR3_TXE | UTCR3_RXE | UTCR3_RIE, micro->base + UTCR3);
 	val = readl(micro->base + UTCR3);
 	val &= ~UTCR3_TIE;
 	writel(val, micro->base + UTCR3);
 }

 static irqreturn_t micro_serial_isr(int irq, void *dev_id)
 {
 	struct ipaq_micro *micro = dev_id;
 	struct ipaq_micro_txdev *tx = &micro->tx;
 	u32 status;

 	status = readl(micro->base + UTSR0);
 	do {
 		if (status & (UTSR0_RID | UTSR0_RFS)) {
 			if (status & UTSR0_RID)
 				/* Clear the Receiver IDLE bit */
 				writel(UTSR0_RID, micro->base + UTSR0);
 			micro_rx_chars(micro);
 		}

 		/* Clear break bits */
 		if (status & (UTSR0_RBB | UTSR0_REB))
 			writel(status & (UTSR0_RBB | UTSR0_REB),
 			       micro->base + UTSR0);

 		if (status & UTSR0_TFS)
 			micro_tx_chars(micro);

 		status = readl(micro->base + UTSR0);

 	} while (((tx->index < tx->len) && (status & UTSR0_TFS)) ||
 		 (status & (UTSR0_RFS | UTSR0_RID)));

 	return IRQ_HANDLED;
 }

 static const struct mfd_cell micro_cells[] = {
 	{ .name = "ipaq-micro-backlight", },
 	{ .name = "ipaq-micro-battery", },
 	{ .name = "ipaq-micro-keys", },
 	{ .name = "ipaq-micro-ts", },
 	{ .name = "ipaq-micro-leds", },
 };

 static int __maybe_unused micro_resume(struct device *dev)
 {
 	struct ipaq_micro *micro = dev_get_drvdata(dev);

 	micro_reset_comm(micro);
 	mdelay(10);

 	return 0;
 }

 static int __init micro_probe(struct platform_device *pdev)
 {
 	struct ipaq_micro *micro;
 	struct resource *res;
 	int ret;
 	int irq;

 	micro = devm_kzalloc(&pdev->dev, sizeof(*micro), GFP_KERNEL);
 	if (!micro)
 		return -ENOMEM;

 	micro->dev = &pdev->dev;

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	if (!res)
 		return -EINVAL;

 	micro->base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(micro->base))
 		return PTR_ERR(micro->base);

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 	if (!res)
 		return -EINVAL;

 	micro->sdlc = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(micro->sdlc))
 		return PTR_ERR(micro->sdlc);

 	micro_reset_comm(micro);

 	irq = platform_get_irq(pdev, 0);
 	if (!irq)
 		return -EINVAL;
 	ret = devm_request_irq(&pdev->dev, irq, micro_serial_isr,
 			       IRQF_SHARED, "ipaq-micro",
 			       micro);
 	if (ret) {
 		dev_err(&pdev->dev, "unable to grab serial port IRQ\n");
 		return ret;
 	} else
 		dev_info(&pdev->dev, "grabbed serial port IRQ\n");

 	spin_lock_init(&micro->lock);
 	INIT_LIST_HEAD(&micro->queue);
 	platform_set_drvdata(pdev, micro);

 	ret = mfd_add_devices(&pdev->dev, pdev->id, micro_cells,
 			      ARRAY_SIZE(micro_cells), NULL, 0, NULL);
 	if (ret) {
 		dev_err(&pdev->dev, "error adding MFD cells");
 		return ret;
 	}

 	/* Check version */
 	ipaq_micro_get_version(micro);
 	dev_info(&pdev->dev, "Atmel micro ASIC version %s\n", micro->version);
 	ipaq_micro_eeprom_dump(micro);

 	return 0;
 }

 static const struct dev_pm_ops micro_dev_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(NULL, micro_resume)
 };

 static struct platform_driver micro_device_driver = {
 	.driver   = {
 		.name	= "ipaq-h3xxx-micro",
 		.pm	= &micro_dev_pm_ops,
 		.suppress_bind_attrs = true,
 	},
 };
 builtin_platform_driver_probe(micro_device_driver, micro_probe);
	/*
	* Compaq iPAQ h3xxx Atmel microcontroller companion support
	*
	* This is an Atmel AT90LS8535 with a special flashed-in firmware that
	* implements the special protocol used by this driver.
	*
	* based on previous kernel 2.4 version by Andrew Christian
	* Author : Alessandro Gardich <gremlin@gremlin.it>
	* Author : Dmitry Artamonow <mad_soft@inbox.ru>
	* Author : Linus Walleij <linus.walleij@linaro.org>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/interrupt.h>
	#include <linux/pm.h>
	#include <linux/delay.h>
	#include <linux/device.h>
	#include <linux/platform_device.h>
	#include <linux/io.h>
	#include <linux/mfd/core.h>
	#include <linux/mfd/ipaq-micro.h>
	#include <linux/string.h>
	#include <linux/random.h>
	#include <linux/slab.h>
	#include <linux/list.h>

	#include <mach/hardware.h>

	static void ipaq_micro_trigger_tx(struct ipaq_micro *micro)
	{
	struct ipaq_micro_txdev *tx = &micro->tx;
	struct ipaq_micro_msg *msg = micro->msg;
	int i, bp;
	u8 checksum;
	u32 val;

	bp = 0;
	tx->buf[bp++] = CHAR_SOF;

	checksum = ((msg->id & 0x0f) << 4) \| (msg->tx_len & 0x0f);
	tx->buf[bp++] = checksum;

	for (i = 0; i < msg->tx_len; i++) {
	tx->buf[bp++] = msg->tx_data[i];
	checksum += msg->tx_data[i];
	}

	tx->buf[bp++] = checksum;
	tx->len = bp;
	tx->index = 0;
	print_hex_dump_debug("data: ", DUMP_PREFIX_OFFSET, 16, 1,
	tx->buf, tx->len, true);

	/* Enable interrupt */
	val = readl(micro->base + UTCR3);
	val \|= UTCR3_TIE;
	writel(val, micro->base + UTCR3);
	}

	int ipaq_micro_tx_msg(struct ipaq_micro micro, struct ipaq_micro_msg msg)
	{
	unsigned long flags;

	dev_dbg(micro->dev, "TX msg: %02x, %d bytes\n", msg->id, msg->tx_len);

	spin_lock_irqsave(&micro->lock, flags);
	if (micro->msg) {
	list_add_tail(&msg->node, &micro->queue);
	spin_unlock_irqrestore(&micro->lock, flags);
	return 0;
	}
	micro->msg = msg;
	ipaq_micro_trigger_tx(micro);
	spin_unlock_irqrestore(&micro->lock, flags);
	return 0;
	}
	EXPORT_SYMBOL(ipaq_micro_tx_msg);

	static void micro_rx_msg(struct ipaq_micro micro, u8 id, int len, u8 data)
	{
	int i;

	dev_dbg(micro->dev, "RX msg: %02x, %d bytes\n", id, len);

	spin_lock(&micro->lock);
	switch (id) {
	case MSG_VERSION:
	case MSG_EEPROM_READ:
	case MSG_EEPROM_WRITE:
	case MSG_BACKLIGHT:
	case MSG_NOTIFY_LED:
	case MSG_THERMAL_SENSOR:
	case MSG_BATTERY:
	/* Handle synchronous messages */
	if (micro->msg && micro->msg->id == id) {
	struct ipaq_micro_msg *msg = micro->msg;

	memcpy(msg->rx_data, data, len);
	msg->rx_len = len;
	complete(&micro->msg->ack);
	if (!list_empty(&micro->queue)) {
	micro->msg = list_entry(micro->queue.next,
	struct ipaq_micro_msg,
	node);
	list_del_init(&micro->msg->node);
	ipaq_micro_trigger_tx(micro);
	} else
	micro->msg = NULL;
	dev_dbg(micro->dev, "OK RX message 0x%02x\n", id);
	} else {
	dev_err(micro->dev,
	"out of band RX message 0x%02x\n", id);
	if (!micro->msg)
	dev_info(micro->dev, "no message queued\n");
	else
	dev_info(micro->dev, "expected message %02x\n",
	micro->msg->id);
	}
	break;
	case MSG_KEYBOARD:
	if (micro->key)
	micro->key(micro->key_data, len, data);
	else
	dev_dbg(micro->dev, "key message ignored, no handle\n");
	break;
	case MSG_TOUCHSCREEN:
	if (micro->ts)
	micro->ts(micro->ts_data, len, data);
	else
	dev_dbg(micro->dev, "touchscreen message ignored, no handle\n");
	break;
	default:
	dev_err(micro->dev,
	"unknown msg %d [%d] ", id, len);
	for (i = 0; i < len; ++i)
	pr_cont("0x%02x ", data[i]);
	pr_cont("\n");
	}
	spin_unlock(&micro->lock);
	}

	static void micro_process_char(struct ipaq_micro *micro, u8 ch)
	{
	struct ipaq_micro_rxdev *rx = &micro->rx;

	switch (rx->state) {
	case STATE_SOF: /* Looking for SOF */
	if (ch == CHAR_SOF)
	rx->state = STATE_ID; /* Next byte is the id and len */
	break;
	case STATE_ID: /* Looking for id and len byte */
	rx->id = (ch & 0xf0) >> 4;
	rx->len = (ch & 0x0f);
	rx->index = 0;
	rx->chksum = ch;
	rx->state = (rx->len > 0) ? STATE_DATA : STATE_CHKSUM;
	break;
	case STATE_DATA: /* Looking for 'len' data bytes */
	rx->chksum += ch;
	rx->buf[rx->index] = ch;
	if (++rx->index == rx->len)
	rx->state = STATE_CHKSUM;
	break;
	case STATE_CHKSUM: /* Looking for the checksum */
	if (ch == rx->chksum)
	micro_rx_msg(micro, rx->id, rx->len, rx->buf);
	rx->state = STATE_SOF;
	break;
	}
	}

	static void micro_rx_chars(struct ipaq_micro *micro)
	{
	u32 status, ch;

	while ((status = readl(micro->base + UTSR1)) & UTSR1_RNE) {
	ch = readl(micro->base + UTDR);
	if (status & UTSR1_PRE)
	dev_err(micro->dev, "rx: parity error\n");
	else if (status & UTSR1_FRE)
	dev_err(micro->dev, "rx: framing error\n");
	else if (status & UTSR1_ROR)
	dev_err(micro->dev, "rx: overrun error\n");
	micro_process_char(micro, ch);
	}
	}

	static void ipaq_micro_get_version(struct ipaq_micro *micro)
	{
	struct ipaq_micro_msg msg = {
	.id = MSG_VERSION,
	};

	ipaq_micro_tx_msg_sync(micro, &msg);
	if (msg.rx_len == 4) {
	memcpy(micro->version, msg.rx_data, 4);
	micro->version[4] = '\0';
	} else if (msg.rx_len == 9) {
	memcpy(micro->version, msg.rx_data, 4);
	micro->version[4] = '\0';
	/* Bytes 4-7 are "pack", byte 8 is "boot type" */
	} else {
	dev_err(micro->dev,
	"illegal version message %d bytes\n", msg.rx_len);
	}
	}

	static void ipaq_micro_eeprom_read(struct ipaq_micro *micro,
	u8 address, u8 len, u8 *data)
	{
	struct ipaq_micro_msg msg = {
	.id = MSG_EEPROM_READ,
	};
	u8 i;

	for (i = 0; i < len; i++) {
	msg.tx_data[0] = address + i;
	msg.tx_data[1] = 1;
	msg.tx_len = 2;
	ipaq_micro_tx_msg_sync(micro, &msg);
	memcpy(data + (i * 2), msg.rx_data, 2);
	}
	}

	static char ipaq_micro_str(u8 wchar, u8 len)
	{
	char retstr[256];
	u8 i;

	for (i = 0; i < len / 2; i++)
	retstr[i] = wchar[i * 2];
	return kstrdup(retstr, GFP_KERNEL);
	}

	static u16 ipaq_micro_to_u16(u8 *data)
	{
	return data[1] << 8 \| data[0];
	}

	static void __init ipaq_micro_eeprom_dump(struct ipaq_micro *micro)
	{
	u8 dump[256];
	char *str;

	ipaq_micro_eeprom_read(micro, 0, 128, dump);
	str = ipaq_micro_str(dump, 10);
	if (str) {
	dev_info(micro->dev, "HW version %s\n", str);
	kfree(str);
	}
	str = ipaq_micro_str(dump+10, 40);
	if (str) {
	dev_info(micro->dev, "serial number: %s\n", str);
	/* Feed the random pool with this */
	add_device_randomness(str, strlen(str));
	kfree(str);
	}
	str = ipaq_micro_str(dump+50, 20);
	if (str) {
	dev_info(micro->dev, "module ID: %s\n", str);
	kfree(str);
	}
	str = ipaq_micro_str(dump+70, 10);
	if (str) {
	dev_info(micro->dev, "product revision: %s\n", str);
	kfree(str);
	}
	dev_info(micro->dev, "product ID: %u\n", ipaq_micro_to_u16(dump+80));
	dev_info(micro->dev, "frame rate: %u fps\n",
	ipaq_micro_to_u16(dump+82));
	dev_info(micro->dev, "page mode: %u\n", ipaq_micro_to_u16(dump+84));
	dev_info(micro->dev, "country ID: %u\n", ipaq_micro_to_u16(dump+86));
	dev_info(micro->dev, "color display: %s\n",
	ipaq_micro_to_u16(dump+88) ? "yes" : "no");
	dev_info(micro->dev, "ROM size: %u MiB\n", ipaq_micro_to_u16(dump+90));
	dev_info(micro->dev, "RAM size: %u KiB\n", ipaq_micro_to_u16(dump+92));
	dev_info(micro->dev, "screen: %u x %u\n",
	ipaq_micro_to_u16(dump+94), ipaq_micro_to_u16(dump+96));
	print_hex_dump_debug("eeprom: ", DUMP_PREFIX_OFFSET, 16, 1,
	dump, 256, true);

	}

	static void micro_tx_chars(struct ipaq_micro *micro)
	{
	struct ipaq_micro_txdev *tx = &micro->tx;
	u32 val;

	while ((tx->index < tx->len) &&
	(readl(micro->base + UTSR1) & UTSR1_TNF)) {
	writel(tx->buf[tx->index], micro->base + UTDR);
	tx->index++;
	}

	/* Stop interrupts */
	val = readl(micro->base + UTCR3);
	val &= ~UTCR3_TIE;
	writel(val, micro->base + UTCR3);
	}

	static void micro_reset_comm(struct ipaq_micro *micro)
	{
	struct ipaq_micro_rxdev *rx = &micro->rx;
	u32 val;

	if (micro->msg)
	complete(&micro->msg->ack);

	/* Initialize Serial channel protocol frame */
	rx->state = STATE_SOF; /* Reset the state machine */

	/* Set up interrupts */
	writel(0x01, micro->sdlc + 0x0); /* Select UART mode */

	/* Clean up CR3 */
	writel(0x0, micro->base + UTCR3);

	/* Format: 8N1 */
	writel(UTCR0_8BitData \| UTCR0_1StpBit, micro->base + UTCR0);

	/* Baud rate: 115200 */
	writel(0x0, micro->base + UTCR1);
	writel(0x1, micro->base + UTCR2);

	/* Clear SR0 */
	writel(0xff, micro->base + UTSR0);

	/* Enable RX int, disable TX int */
	writel(UTCR3_TXE \| UTCR3_RXE \| UTCR3_RIE, micro->base + UTCR3);
	val = readl(micro->base + UTCR3);
	val &= ~UTCR3_TIE;
	writel(val, micro->base + UTCR3);
	}

	static irqreturn_t micro_serial_isr(int irq, void *dev_id)
	{
	struct ipaq_micro *micro = dev_id;
	struct ipaq_micro_txdev *tx = &micro->tx;
	u32 status;

	status = readl(micro->base + UTSR0);
	do {
	if (status & (UTSR0_RID \| UTSR0_RFS)) {
	if (status & UTSR0_RID)
	/* Clear the Receiver IDLE bit */
	writel(UTSR0_RID, micro->base + UTSR0);
	micro_rx_chars(micro);
	}

	/* Clear break bits */
	if (status & (UTSR0_RBB \| UTSR0_REB))
	writel(status & (UTSR0_RBB \| UTSR0_REB),
	micro->base + UTSR0);

	if (status & UTSR0_TFS)
	micro_tx_chars(micro);

	status = readl(micro->base + UTSR0);

	} while (((tx->index < tx->len) && (status & UTSR0_TFS)) \|\|
	(status & (UTSR0_RFS \| UTSR0_RID)));

	return IRQ_HANDLED;
	}

	static const struct mfd_cell micro_cells[] = {
	{ .name = "ipaq-micro-backlight", },
	{ .name = "ipaq-micro-battery", },
	{ .name = "ipaq-micro-keys", },
	{ .name = "ipaq-micro-ts", },
	{ .name = "ipaq-micro-leds", },
	};

	static int __maybe_unused micro_resume(struct device *dev)
	{
	struct ipaq_micro *micro = dev_get_drvdata(dev);

	micro_reset_comm(micro);
	mdelay(10);

	return 0;
	}

	static int __init micro_probe(struct platform_device *pdev)
	{
	struct ipaq_micro *micro;
	struct resource *res;
	int ret;
	int irq;

	micro = devm_kzalloc(&pdev->dev, sizeof(*micro), GFP_KERNEL);
	if (!micro)
	return -ENOMEM;

	micro->dev = &pdev->dev;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
	return -EINVAL;

	micro->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(micro->base))
	return PTR_ERR(micro->base);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	if (!res)
	return -EINVAL;

	micro->sdlc = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(micro->sdlc))
	return PTR_ERR(micro->sdlc);

	micro_reset_comm(micro);

	irq = platform_get_irq(pdev, 0);
	if (!irq)
	return -EINVAL;
	ret = devm_request_irq(&pdev->dev, irq, micro_serial_isr,
	IRQF_SHARED, "ipaq-micro",
	micro);
	if (ret) {
	dev_err(&pdev->dev, "unable to grab serial port IRQ\n");
	return ret;
	} else
	dev_info(&pdev->dev, "grabbed serial port IRQ\n");

	spin_lock_init(&micro->lock);
	INIT_LIST_HEAD(&micro->queue);
	platform_set_drvdata(pdev, micro);

	ret = mfd_add_devices(&pdev->dev, pdev->id, micro_cells,
	ARRAY_SIZE(micro_cells), NULL, 0, NULL);
	if (ret) {
	dev_err(&pdev->dev, "error adding MFD cells");
	return ret;
	}

	/* Check version */
	ipaq_micro_get_version(micro);
	dev_info(&pdev->dev, "Atmel micro ASIC version %s\n", micro->version);
	ipaq_micro_eeprom_dump(micro);

	return 0;
	}

	static const struct dev_pm_ops micro_dev_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(NULL, micro_resume)
	};

	static struct platform_driver micro_device_driver = {
	.driver = {
	.name = "ipaq-h3xxx-micro",
	.pm = &micro_dev_pm_ops,
	.suppress_bind_attrs = true,
	},
	};
	builtin_platform_driver_probe(micro_device_driver, micro_probe);