1 files changed, 675 insertions, 0 deletions

diff --git a/drivers/w1/masters/ds1wm.c b/drivers/w1/masters/ds1wm.c
new file mode 100644
index 000000000..f661695fb
--- /dev/null
+++ b/drivers/w1/masters/ds1wm.c
@@ -0,0 +1,675 @@
+/*
+ * 1-wire busmaster driver for DS1WM and ASICs with embedded DS1WMs
+ * such as HP iPAQs (including h5xxx, h2200, and devices with ASIC3
+ * like hx4700).
+ *
+ * Copyright (c) 2004-2005, Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
+ * Copyright (c) 2004-2007, Matt Reimer <mreimer@vpop.net>
+ *
+ * Use consistent with the GNU GPL is permitted,
+ * provided that this copyright notice is
+ * preserved in its entirety in all copies and derived works.
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/pm.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/ds1wm.h>
+#include <linux/slab.h>
+
+#include <asm/io.h>
+
+#include <linux/w1.h>
+
+
+#define DS1WM_CMD	0x00	/* R/W 4 bits command */
+#define DS1WM_DATA	0x01	/* R/W 8 bits, transmit/receive buffer */
+#define DS1WM_INT	0x02	/* R/W interrupt status */
+#define DS1WM_INT_EN	0x03	/* R/W interrupt enable */
+#define DS1WM_CLKDIV	0x04	/* R/W 5 bits of divisor and pre-scale */
+#define DS1WM_CNTRL	0x05	/* R/W master control register (not used yet) */
+
+#define DS1WM_CMD_1W_RESET  (1 << 0)	/* force reset on 1-wire bus */
+#define DS1WM_CMD_SRA	    (1 << 1)	/* enable Search ROM accelerator mode */
+#define DS1WM_CMD_DQ_OUTPUT (1 << 2)	/* write only - forces bus low */
+#define DS1WM_CMD_DQ_INPUT  (1 << 3)	/* read only - reflects state of bus */
+#define DS1WM_CMD_RST	    (1 << 5)	/* software reset */
+#define DS1WM_CMD_OD	    (1 << 7)	/* overdrive */
+
+#define DS1WM_INT_PD	    (1 << 0)	/* presence detect */
+#define DS1WM_INT_PDR	    (1 << 1)	/* presence detect result */
+#define DS1WM_INT_TBE	    (1 << 2)	/* tx buffer empty */
+#define DS1WM_INT_TSRE	    (1 << 3)	/* tx shift register empty */
+#define DS1WM_INT_RBF	    (1 << 4)	/* rx buffer full */
+#define DS1WM_INT_RSRF	    (1 << 5)	/* rx shift register full */
+
+#define DS1WM_INTEN_EPD	    (1 << 0)	/* enable presence detect int */
+#define DS1WM_INTEN_IAS	    (1 << 1)	/* INTR active state */
+#define DS1WM_INTEN_ETBE    (1 << 2)	/* enable tx buffer empty int */
+#define DS1WM_INTEN_ETMT    (1 << 3)	/* enable tx shift register empty int */
+#define DS1WM_INTEN_ERBF    (1 << 4)	/* enable rx buffer full int */
+#define DS1WM_INTEN_ERSRF   (1 << 5)	/* enable rx shift register full int */
+#define DS1WM_INTEN_DQO	    (1 << 6)	/* enable direct bus driving ops */
+
+#define DS1WM_INTEN_NOT_IAS (~DS1WM_INTEN_IAS)	/* all but INTR active state */
+
+#define DS1WM_TIMEOUT (HZ * 5)
+
+static struct {
+	unsigned long freq;
+	unsigned long divisor;
+} freq[] = {
+	{   1000000, 0x80 },
+	{   2000000, 0x84 },
+	{   3000000, 0x81 },
+	{   4000000, 0x88 },
+	{   5000000, 0x82 },
+	{   6000000, 0x85 },
+	{   7000000, 0x83 },
+	{   8000000, 0x8c },
+	{  10000000, 0x86 },
+	{  12000000, 0x89 },
+	{  14000000, 0x87 },
+	{  16000000, 0x90 },
+	{  20000000, 0x8a },
+	{  24000000, 0x8d },
+	{  28000000, 0x8b },
+	{  32000000, 0x94 },
+	{  40000000, 0x8e },
+	{  48000000, 0x91 },
+	{  56000000, 0x8f },
+	{  64000000, 0x98 },
+	{  80000000, 0x92 },
+	{  96000000, 0x95 },
+	{ 112000000, 0x93 },
+	{ 128000000, 0x9c },
+/* you can continue this table, consult the OPERATION - CLOCK DIVISOR
+   section of the ds1wm spec sheet. */
+};
+
+struct ds1wm_data {
+	void     __iomem *map;
+	unsigned int      bus_shift; /* # of shifts to calc register offsets */
+	bool      is_hw_big_endian;
+	struct platform_device *pdev;
+	const struct mfd_cell   *cell;
+	int      irq;
+	int      slave_present;
+	void     *reset_complete;
+	void     *read_complete;
+	void     *write_complete;
+	int      read_error;
+	/* last byte received */
+	u8       read_byte;
+	/* byte to write that makes all intr disabled, */
+	/* considering active_state (IAS) (optimization) */
+	u8       int_en_reg_none;
+	unsigned int reset_recover_delay; /* see ds1wm.h */
+};
+
+static inline void ds1wm_write_register(struct ds1wm_data *ds1wm_data, u32 reg,
+					u8 val)
+{
+	if (ds1wm_data->is_hw_big_endian) {
+		switch (ds1wm_data->bus_shift) {
+		case 0:
+			iowrite8(val, ds1wm_data->map + (reg << 0));
+			break;
+		case 1:
+			iowrite16be((u16)val, ds1wm_data->map + (reg << 1));
+			break;
+		case 2:
+			iowrite32be((u32)val, ds1wm_data->map + (reg << 2));
+			break;
+		}
+	} else {
+		switch (ds1wm_data->bus_shift) {
+		case 0:
+			iowrite8(val, ds1wm_data->map + (reg << 0));
+			break;
+		case 1:
+			iowrite16((u16)val, ds1wm_data->map + (reg << 1));
+			break;
+		case 2:
+			iowrite32((u32)val, ds1wm_data->map + (reg << 2));
+			break;
+		}
+	}
+}
+
+static inline u8 ds1wm_read_register(struct ds1wm_data *ds1wm_data, u32 reg)
+{
+	u32 val = 0;
+
+	if (ds1wm_data->is_hw_big_endian) {
+		switch (ds1wm_data->bus_shift) {
+		case 0:
+			val = ioread8(ds1wm_data->map + (reg << 0));
+			break;
+		case 1:
+			val = ioread16be(ds1wm_data->map + (reg << 1));
+			break;
+		case 2:
+			val = ioread32be(ds1wm_data->map + (reg << 2));
+			break;
+		}
+	} else {
+		switch (ds1wm_data->bus_shift) {
+		case 0:
+			val = ioread8(ds1wm_data->map + (reg << 0));
+			break;
+		case 1:
+			val = ioread16(ds1wm_data->map + (reg << 1));
+			break;
+		case 2:
+			val = ioread32(ds1wm_data->map + (reg << 2));
+			break;
+		}
+	}
+	dev_dbg(&ds1wm_data->pdev->dev,
+		"ds1wm_read_register reg: %d, 32 bit val:%x\n", reg, val);
+	return (u8)val;
+}
+
+
+static irqreturn_t ds1wm_isr(int isr, void *data)
+{
+	struct ds1wm_data *ds1wm_data = data;
+	u8 intr;
+	u8 inten = ds1wm_read_register(ds1wm_data, DS1WM_INT_EN);
+	/* if no bits are set in int enable register (except the IAS)
+	than go no further, reading the regs below has side effects */
+	if (!(inten & DS1WM_INTEN_NOT_IAS))
+		return IRQ_NONE;
+
+	ds1wm_write_register(ds1wm_data,
+		DS1WM_INT_EN, ds1wm_data->int_en_reg_none);
+
+	/* this read action clears the INTR and certain flags in ds1wm */
+	intr = ds1wm_read_register(ds1wm_data, DS1WM_INT);
+
+	ds1wm_data->slave_present = (intr & DS1WM_INT_PDR) ? 0 : 1;
+
+	if ((intr & DS1WM_INT_TSRE) && ds1wm_data->write_complete) {
+		inten &= ~DS1WM_INTEN_ETMT;
+		complete(ds1wm_data->write_complete);
+	}
+	if (intr & DS1WM_INT_RBF) {
+		/* this read clears the RBF flag */
+		ds1wm_data->read_byte = ds1wm_read_register(ds1wm_data,
+		DS1WM_DATA);
+		inten &= ~DS1WM_INTEN_ERBF;
+		if (ds1wm_data->read_complete)
+			complete(ds1wm_data->read_complete);
+	}
+	if ((intr & DS1WM_INT_PD) && ds1wm_data->reset_complete) {
+		inten &= ~DS1WM_INTEN_EPD;
+		complete(ds1wm_data->reset_complete);
+	}
+
+	ds1wm_write_register(ds1wm_data, DS1WM_INT_EN, inten);
+	return IRQ_HANDLED;
+}
+
+static int ds1wm_reset(struct ds1wm_data *ds1wm_data)
+{
+	unsigned long timeleft;
+	DECLARE_COMPLETION_ONSTACK(reset_done);
+
+	ds1wm_data->reset_complete = &reset_done;
+
+	/* enable Presence detect only */
+	ds1wm_write_register(ds1wm_data, DS1WM_INT_EN, DS1WM_INTEN_EPD |
+	ds1wm_data->int_en_reg_none);
+
+	ds1wm_write_register(ds1wm_data, DS1WM_CMD, DS1WM_CMD_1W_RESET);
+
+	timeleft = wait_for_completion_timeout(&reset_done, DS1WM_TIMEOUT);
+	ds1wm_data->reset_complete = NULL;
+	if (!timeleft) {
+		dev_err(&ds1wm_data->pdev->dev, "reset failed, timed out\n");
+		return 1;
+	}
+
+	if (!ds1wm_data->slave_present) {
+		dev_dbg(&ds1wm_data->pdev->dev, "reset: no devices found\n");
+		return 1;
+	}
+
+	if (ds1wm_data->reset_recover_delay)
+		msleep(ds1wm_data->reset_recover_delay);
+
+	return 0;
+}
+
+static int ds1wm_write(struct ds1wm_data *ds1wm_data, u8 data)
+{
+	unsigned long timeleft;
+	DECLARE_COMPLETION_ONSTACK(write_done);
+	ds1wm_data->write_complete = &write_done;
+
+	ds1wm_write_register(ds1wm_data, DS1WM_INT_EN,
+	ds1wm_data->int_en_reg_none | DS1WM_INTEN_ETMT);
+
+	ds1wm_write_register(ds1wm_data, DS1WM_DATA, data);
+
+	timeleft = wait_for_completion_timeout(&write_done, DS1WM_TIMEOUT);
+
+	ds1wm_data->write_complete = NULL;
+	if (!timeleft) {
+		dev_err(&ds1wm_data->pdev->dev, "write failed, timed out\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static u8 ds1wm_read(struct ds1wm_data *ds1wm_data, unsigned char write_data)
+{
+	unsigned long timeleft;
+	u8 intEnable = DS1WM_INTEN_ERBF | ds1wm_data->int_en_reg_none;
+	DECLARE_COMPLETION_ONSTACK(read_done);
+
+	ds1wm_read_register(ds1wm_data, DS1WM_DATA);
+
+	ds1wm_data->read_complete = &read_done;
+	ds1wm_write_register(ds1wm_data, DS1WM_INT_EN, intEnable);
+
+	ds1wm_write_register(ds1wm_data, DS1WM_DATA, write_data);
+	timeleft = wait_for_completion_timeout(&read_done, DS1WM_TIMEOUT);
+
+	ds1wm_data->read_complete = NULL;
+	if (!timeleft) {
+		dev_err(&ds1wm_data->pdev->dev, "read failed, timed out\n");
+		ds1wm_data->read_error = -ETIMEDOUT;
+		return 0xFF;
+	}
+	ds1wm_data->read_error = 0;
+	return ds1wm_data->read_byte;
+}
+
+static int ds1wm_find_divisor(int gclk)
+{
+	int i;
+
+	for (i = ARRAY_SIZE(freq)-1; i >= 0; --i)
+		if (gclk >= freq[i].freq)
+			return freq[i].divisor;
+
+	return 0;
+}
+
+static void ds1wm_up(struct ds1wm_data *ds1wm_data)
+{
+	int divisor;
+	struct device *dev = &ds1wm_data->pdev->dev;
+	struct ds1wm_driver_data *plat = dev_get_platdata(dev);
+
+	if (ds1wm_data->cell->enable)
+		ds1wm_data->cell->enable(ds1wm_data->pdev);
+
+	divisor = ds1wm_find_divisor(plat->clock_rate);
+	dev_dbg(dev, "found divisor 0x%x for clock %d\n",
+		divisor, plat->clock_rate);
+	if (divisor == 0) {
+		dev_err(dev, "no suitable divisor for %dHz clock\n",
+			plat->clock_rate);
+		return;
+	}
+	ds1wm_write_register(ds1wm_data, DS1WM_CLKDIV, divisor);
+
+	/* Let the w1 clock stabilize. */
+	msleep(1);
+
+	ds1wm_reset(ds1wm_data);
+}
+
+static void ds1wm_down(struct ds1wm_data *ds1wm_data)
+{
+	ds1wm_reset(ds1wm_data);
+
+	/* Disable interrupts. */
+	ds1wm_write_register(ds1wm_data, DS1WM_INT_EN,
+		ds1wm_data->int_en_reg_none);
+
+	if (ds1wm_data->cell->disable)
+		ds1wm_data->cell->disable(ds1wm_data->pdev);
+}
+
+/* --------------------------------------------------------------------- */
+/* w1 methods */
+
+static u8 ds1wm_read_byte(void *data)
+{
+	struct ds1wm_data *ds1wm_data = data;
+
+	return ds1wm_read(ds1wm_data, 0xff);
+}
+
+static void ds1wm_write_byte(void *data, u8 byte)
+{
+	struct ds1wm_data *ds1wm_data = data;
+
+	ds1wm_write(ds1wm_data, byte);
+}
+
+static u8 ds1wm_reset_bus(void *data)
+{
+	struct ds1wm_data *ds1wm_data = data;
+
+	ds1wm_reset(ds1wm_data);
+
+	return 0;
+}
+
+static void ds1wm_search(void *data, struct w1_master *master_dev,
+			u8 search_type, w1_slave_found_callback slave_found)
+{
+	struct ds1wm_data *ds1wm_data = data;
+	int i;
+	int ms_discrep_bit = -1;
+	u64 r = 0; /* holds the progress of the search */
+	u64 r_prime, d;
+	unsigned slaves_found = 0;
+	unsigned int pass = 0;
+
+	dev_dbg(&ds1wm_data->pdev->dev, "search begin\n");
+	while (true) {
+		++pass;
+		if (pass > 100) {
+			dev_dbg(&ds1wm_data->pdev->dev,
+				"too many attempts (100), search aborted\n");
+			return;
+		}
+
+		mutex_lock(&master_dev->bus_mutex);
+		if (ds1wm_reset(ds1wm_data)) {
+			mutex_unlock(&master_dev->bus_mutex);
+			dev_dbg(&ds1wm_data->pdev->dev,
+				"pass: %d reset error (or no slaves)\n", pass);
+			break;
+		}
+
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d r : %0#18llx writing SEARCH_ROM\n", pass, r);
+		ds1wm_write(ds1wm_data, search_type);
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d entering ASM\n", pass);
+		ds1wm_write_register(ds1wm_data, DS1WM_CMD, DS1WM_CMD_SRA);
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d beginning nibble loop\n", pass);
+
+		r_prime = 0;
+		d = 0;
+		/* we work one nibble at a time */
+		/* each nibble is interleaved to form a byte */
+		for (i = 0; i < 16; i++) {
+
+			unsigned char resp, _r, _r_prime, _d;
+
+			_r = (r >> (4*i)) & 0xf;
+			_r = ((_r & 0x1) << 1) |
+			((_r & 0x2) << 2) |
+			((_r & 0x4) << 3) |
+			((_r & 0x8) << 4);
+
+			/* writes _r, then reads back: */
+			resp = ds1wm_read(ds1wm_data, _r);
+
+			if (ds1wm_data->read_error) {
+				dev_err(&ds1wm_data->pdev->dev,
+				"pass: %d nibble: %d read error\n", pass, i);
+				break;
+			}
+
+			_r_prime = ((resp & 0x02) >> 1) |
+			((resp & 0x08) >> 2) |
+			((resp & 0x20) >> 3) |
+			((resp & 0x80) >> 4);
+
+			_d = ((resp & 0x01) >> 0) |
+			((resp & 0x04) >> 1) |
+			((resp & 0x10) >> 2) |
+			((resp & 0x40) >> 3);
+
+			r_prime |= (unsigned long long) _r_prime << (i * 4);
+			d |= (unsigned long long) _d << (i * 4);
+
+		}
+		if (ds1wm_data->read_error) {
+			mutex_unlock(&master_dev->bus_mutex);
+			dev_err(&ds1wm_data->pdev->dev,
+				"pass: %d read error, retrying\n", pass);
+			break;
+		}
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d r\': %0#18llx d:%0#18llx\n",
+			pass, r_prime, d);
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d nibble loop complete, exiting ASM\n", pass);
+		ds1wm_write_register(ds1wm_data, DS1WM_CMD, ~DS1WM_CMD_SRA);
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d resetting bus\n", pass);
+		ds1wm_reset(ds1wm_data);
+		mutex_unlock(&master_dev->bus_mutex);
+		if ((r_prime & ((u64)1 << 63)) && (d & ((u64)1 << 63))) {
+			dev_err(&ds1wm_data->pdev->dev,
+				"pass: %d bus error, retrying\n", pass);
+			continue; /* start over */
+		}
+
+
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d found %0#18llx\n", pass, r_prime);
+		slave_found(master_dev, r_prime);
+		++slaves_found;
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d complete, preparing next pass\n", pass);
+
+		/* any discrepency found which we already choose the
+		   '1' branch is now is now irrelevant we reveal the
+		   next branch with this: */
+		d &= ~r;
+		/* find last bit set, i.e. the most signif. bit set */
+		ms_discrep_bit = fls64(d) - 1;
+		dev_dbg(&ds1wm_data->pdev->dev,
+			"pass: %d new d:%0#18llx MS discrep bit:%d\n",
+			pass, d, ms_discrep_bit);
+
+		/* prev_ms_discrep_bit = ms_discrep_bit;
+		   prepare for next ROM search:		    */
+		if (ms_discrep_bit == -1)
+			break;
+
+		r = (r &  ~(~0ull << (ms_discrep_bit))) | 1 << ms_discrep_bit;
+	} /* end while true */
+	dev_dbg(&ds1wm_data->pdev->dev,
+		"pass: %d total: %d search done ms d bit pos: %d\n", pass,
+		slaves_found, ms_discrep_bit);
+}
+
+/* --------------------------------------------------------------------- */
+
+static struct w1_bus_master ds1wm_master = {
+	.read_byte  = ds1wm_read_byte,
+	.write_byte = ds1wm_write_byte,
+	.reset_bus  = ds1wm_reset_bus,
+	.search	    = ds1wm_search,
+};
+
+static int ds1wm_probe(struct platform_device *pdev)
+{
+	struct ds1wm_data *ds1wm_data;
+	struct ds1wm_driver_data *plat;
+	struct resource *res;
+	int ret;
+	u8 inten;
+
+	if (!pdev)
+		return -ENODEV;
+
+	ds1wm_data = devm_kzalloc(&pdev->dev, sizeof(*ds1wm_data), GFP_KERNEL);
+	if (!ds1wm_data)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, ds1wm_data);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENXIO;
+	ds1wm_data->map = devm_ioremap(&pdev->dev, res->start,
+				       resource_size(res));
+	if (!ds1wm_data->map)
+		return -ENOMEM;
+
+	ds1wm_data->pdev = pdev;
+	ds1wm_data->cell = mfd_get_cell(pdev);
+	if (!ds1wm_data->cell)
+		return -ENODEV;
+	plat = dev_get_platdata(&pdev->dev);
+	if (!plat)
+		return -ENODEV;
+
+	/* how many bits to shift register number to get register offset */
+	if (plat->bus_shift > 2) {
+		dev_err(&ds1wm_data->pdev->dev,
+			"illegal bus shift %d, not written",
+			ds1wm_data->bus_shift);
+		return -EINVAL;
+	}
+
+	ds1wm_data->bus_shift = plat->bus_shift;
+	/* make sure resource has space for 8 registers */
+	if ((8 << ds1wm_data->bus_shift) > resource_size(res)) {
+		dev_err(&ds1wm_data->pdev->dev,
+			"memory resource size %d to small, should be %d\n",
+			(int)resource_size(res),
+			8 << ds1wm_data->bus_shift);
+		return -EINVAL;
+	}
+
+	ds1wm_data->is_hw_big_endian = plat->is_hw_big_endian;
+
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!res)
+		return -ENXIO;
+	ds1wm_data->irq = res->start;
+	ds1wm_data->int_en_reg_none = (plat->active_high ? DS1WM_INTEN_IAS : 0);
+	ds1wm_data->reset_recover_delay = plat->reset_recover_delay;
+
+	/* Mask interrupts, set IAS before claiming interrupt */
+	inten = ds1wm_read_register(ds1wm_data, DS1WM_INT_EN);
+	ds1wm_write_register(ds1wm_data,
+		DS1WM_INT_EN, ds1wm_data->int_en_reg_none);
+
+	if (res->flags & IORESOURCE_IRQ_HIGHEDGE)
+		irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_EDGE_RISING);
+	if (res->flags & IORESOURCE_IRQ_LOWEDGE)
+		irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_EDGE_FALLING);
+	if (res->flags & IORESOURCE_IRQ_HIGHLEVEL)
+		irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_LEVEL_HIGH);
+	if (res->flags & IORESOURCE_IRQ_LOWLEVEL)
+		irq_set_irq_type(ds1wm_data->irq, IRQ_TYPE_LEVEL_LOW);
+
+	ret = devm_request_irq(&pdev->dev, ds1wm_data->irq, ds1wm_isr,
+			IRQF_SHARED, "ds1wm", ds1wm_data);
+	if (ret) {
+		dev_err(&ds1wm_data->pdev->dev,
+			"devm_request_irq %d failed with errno %d\n",
+			ds1wm_data->irq,
+			ret);
+
+		return ret;
+	}
+
+	ds1wm_up(ds1wm_data);
+
+	ds1wm_master.data = (void *)ds1wm_data;
+
+	ret = w1_add_master_device(&ds1wm_master);
+	if (ret)
+		goto err;
+
+	dev_dbg(&ds1wm_data->pdev->dev,
+		"ds1wm: probe successful, IAS: %d, rec.delay: %d, clockrate: %d, bus-shift: %d, is Hw Big Endian: %d\n",
+		plat->active_high,
+		plat->reset_recover_delay,
+		plat->clock_rate,
+		ds1wm_data->bus_shift,
+		ds1wm_data->is_hw_big_endian);
+	return 0;
+
+err:
+	ds1wm_down(ds1wm_data);
+
+	return ret;
+}
+
+#ifdef CONFIG_PM
+static int ds1wm_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct ds1wm_data *ds1wm_data = platform_get_drvdata(pdev);
+
+	ds1wm_down(ds1wm_data);
+
+	return 0;
+}
+
+static int ds1wm_resume(struct platform_device *pdev)
+{
+	struct ds1wm_data *ds1wm_data = platform_get_drvdata(pdev);
+
+	ds1wm_up(ds1wm_data);
+
+	return 0;
+}
+#else
+#define ds1wm_suspend NULL
+#define ds1wm_resume NULL
+#endif
+
+static int ds1wm_remove(struct platform_device *pdev)
+{
+	struct ds1wm_data *ds1wm_data = platform_get_drvdata(pdev);
+
+	w1_remove_master_device(&ds1wm_master);
+	ds1wm_down(ds1wm_data);
+
+	return 0;
+}
+
+static struct platform_driver ds1wm_driver = {
+	.driver   = {
+		.name = "ds1wm",
+	},
+	.probe    = ds1wm_probe,
+	.remove   = ds1wm_remove,
+	.suspend  = ds1wm_suspend,
+	.resume   = ds1wm_resume
+};
+
+static int __init ds1wm_init(void)
+{
+	pr_info("DS1WM w1 busmaster driver - (c) 2004 Szabolcs Gyurko\n");
+	return platform_driver_register(&ds1wm_driver);
+}
+
+static void __exit ds1wm_exit(void)
+{
+	platform_driver_unregister(&ds1wm_driver);
+}
+
+module_init(ds1wm_init);
+module_exit(ds1wm_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
+	"Matt Reimer <mreimer@vpop.net>,"
+	"Jean-Francois Dagenais <dagenaisj@sonatest.com>");
+MODULE_DESCRIPTION("DS1WM w1 busmaster driver");