[net-next-2.6.git] / drivers / gpio / mcp23s08.c

/*
 * mcp23s08.c - SPI gpio expander driver
 */

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/workqueue.h>
#include <linux/mutex.h>

#include <linux/spi/spi.h>
#include <linux/spi/mcp23s08.h>

#include <asm/gpio.h>


/* Registers are all 8 bits wide.
 *
 * The mcp23s17 has twice as many bits, and can be configured to work
 * with either 16 bit registers or with two adjacent 8 bit banks.
 *
 * Also, there are I2C versions of both chips.
 */
#define MCP_IODIR	0x00		/* init/reset:  all ones */
#define MCP_IPOL	0x01
#define MCP_GPINTEN	0x02
#define MCP_DEFVAL	0x03
#define MCP_INTCON	0x04
#define MCP_IOCON	0x05
#	define IOCON_SEQOP	(1 << 5)
#	define IOCON_HAEN	(1 << 3)
#	define IOCON_ODR	(1 << 2)
#	define IOCON_INTPOL	(1 << 1)
#define MCP_GPPU	0x06
#define MCP_INTF	0x07
#define MCP_INTCAP	0x08
#define MCP_GPIO	0x09
#define MCP_OLAT	0x0a

struct mcp23s08 {
	struct spi_device	*spi;
	u8			addr;

	u8			cache[11];
	/* lock protects the cached values */
	struct mutex		lock;

	struct gpio_chip	chip;

	struct work_struct	work;
};

/* A given spi_device can represent up to four mcp23s08 chips
 * sharing the same chipselect but using different addresses
 * (e.g. chips #0 and #3 might be populated, but not #1 or $2).
 * Driver data holds all the per-chip data.
 */
struct mcp23s08_driver_data {
	unsigned		ngpio;
	struct mcp23s08		*mcp[4];
	struct mcp23s08		chip[];
};

static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg)
{
	u8	tx[2], rx[1];
	int	status;

	tx[0] = mcp->addr | 0x01;
	tx[1] = reg;
	status = spi_write_then_read(mcp->spi, tx, sizeof tx, rx, sizeof rx);
	return (status < 0) ? status : rx[0];
}

static int mcp23s08_write(struct mcp23s08 *mcp, unsigned reg, u8 val)
{
	u8	tx[3];

	tx[0] = mcp->addr;
	tx[1] = reg;
	tx[2] = val;
	return spi_write_then_read(mcp->spi, tx, sizeof tx, NULL, 0);
}

static int
mcp23s08_read_regs(struct mcp23s08 *mcp, unsigned reg, u8 *vals, unsigned n)
{
	u8	tx[2];

	if ((n + reg) > sizeof mcp->cache)
		return -EINVAL;
	tx[0] = mcp->addr | 0x01;
	tx[1] = reg;
	return spi_write_then_read(mcp->spi, tx, sizeof tx, vals, n);
}

/*----------------------------------------------------------------------*/

static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
{
	struct mcp23s08	*mcp = container_of(chip, struct mcp23s08, chip);
	int status;

	mutex_lock(&mcp->lock);
	mcp->cache[MCP_IODIR] |= (1 << offset);
	status = mcp23s08_write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
	mutex_unlock(&mcp->lock);
	return status;
}

static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
{
	struct mcp23s08	*mcp = container_of(chip, struct mcp23s08, chip);
	int status;

	mutex_lock(&mcp->lock);

	/* REVISIT reading this clears any IRQ ... */
	status = mcp23s08_read(mcp, MCP_GPIO);
	if (status < 0)
		status = 0;
	else {
		mcp->cache[MCP_GPIO] = status;
		status = !!(status & (1 << offset));
	}
	mutex_unlock(&mcp->lock);
	return status;
}

static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, int value)
{
	u8 olat = mcp->cache[MCP_OLAT];

	if (value)
		olat |= mask;
	else
		olat &= ~mask;
	mcp->cache[MCP_OLAT] = olat;
	return mcp23s08_write(mcp, MCP_OLAT, olat);
}

static void mcp23s08_set(struct gpio_chip *chip, unsigned offset, int value)
{
	struct mcp23s08	*mcp = container_of(chip, struct mcp23s08, chip);
	u8 mask = 1 << offset;

	mutex_lock(&mcp->lock);
	__mcp23s08_set(mcp, mask, value);
	mutex_unlock(&mcp->lock);
}

static int
mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
{
	struct mcp23s08	*mcp = container_of(chip, struct mcp23s08, chip);
	u8 mask = 1 << offset;
	int status;

	mutex_lock(&mcp->lock);
	status = __mcp23s08_set(mcp, mask, value);
	if (status == 0) {
		mcp->cache[MCP_IODIR] &= ~mask;
		status = mcp23s08_write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
	}
	mutex_unlock(&mcp->lock);
	return status;
}

/*----------------------------------------------------------------------*/

#ifdef CONFIG_DEBUG_FS

#include <linux/seq_file.h>

/*
 * This shows more info than the generic gpio dump code:
 * pullups, deglitching, open drain drive.
 */
static void mcp23s08_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
	struct mcp23s08	*mcp;
	char		bank;
	int		t;
	unsigned	mask;

	mcp = container_of(chip, struct mcp23s08, chip);

	/* NOTE: we only handle one bank for now ... */
	bank = '0' + ((mcp->addr >> 1) & 0x3);

	mutex_lock(&mcp->lock);
	t = mcp23s08_read_regs(mcp, 0, mcp->cache, sizeof mcp->cache);
	if (t < 0) {
		seq_printf(s, " I/O ERROR %d\n", t);
		goto done;
	}

	for (t = 0, mask = 1; t < 8; t++, mask <<= 1) {
		const char	*label;

		label = gpiochip_is_requested(chip, t);
		if (!label)
			continue;

		seq_printf(s, " gpio-%-3d P%c.%d (%-12s) %s %s %s",
			chip->base + t, bank, t, label,
			(mcp->cache[MCP_IODIR] & mask) ? "in " : "out",
			(mcp->cache[MCP_GPIO] & mask) ? "hi" : "lo",
			(mcp->cache[MCP_GPPU] & mask) ? "  " : "up");
		/* NOTE:  ignoring the irq-related registers */
		seq_printf(s, "\n");
	}
done:
	mutex_unlock(&mcp->lock);
}

#else
#define mcp23s08_dbg_show	NULL
#endif

/*----------------------------------------------------------------------*/

static int mcp23s08_probe_one(struct spi_device *spi, unsigned addr,
		unsigned base, unsigned pullups)
{
	struct mcp23s08_driver_data	*data = spi_get_drvdata(spi);
	struct mcp23s08			*mcp = data->mcp[addr];
	int				status;
	int				do_update = 0;

	mutex_init(&mcp->lock);

	mcp->spi = spi;
	mcp->addr = 0x40 | (addr << 1);

	mcp->chip.label = "mcp23s08",

	mcp->chip.direction_input = mcp23s08_direction_input;
	mcp->chip.get = mcp23s08_get;
	mcp->chip.direction_output = mcp23s08_direction_output;
	mcp->chip.set = mcp23s08_set;
	mcp->chip.dbg_show = mcp23s08_dbg_show;

	mcp->chip.base = base;
	mcp->chip.ngpio = 8;
	mcp->chip.can_sleep = 1;
	mcp->chip.dev = &spi->dev;
	mcp->chip.owner = THIS_MODULE;

	/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
	 * and MCP_IOCON.HAEN = 1, so we work with all chips.
	 */
	status = mcp23s08_read(mcp, MCP_IOCON);
	if (status < 0)
		goto fail;
	if ((status & IOCON_SEQOP) || !(status & IOCON_HAEN)) {
		status &= ~IOCON_SEQOP;
		status |= IOCON_HAEN;
		status = mcp23s08_write(mcp, MCP_IOCON, (u8) status);
		if (status < 0)
			goto fail;
	}

	/* configure ~100K pullups */
	status = mcp23s08_write(mcp, MCP_GPPU, pullups);
	if (status < 0)
		goto fail;

	status = mcp23s08_read_regs(mcp, 0, mcp->cache, sizeof mcp->cache);
	if (status < 0)
		goto fail;

	/* disable inverter on input */
	if (mcp->cache[MCP_IPOL] != 0) {
		mcp->cache[MCP_IPOL] = 0;
		do_update = 1;
	}

	/* disable irqs */
	if (mcp->cache[MCP_GPINTEN] != 0) {
		mcp->cache[MCP_GPINTEN] = 0;
		do_update = 1;
	}

	if (do_update) {
		u8 tx[4];

		tx[0] = mcp->addr;
		tx[1] = MCP_IPOL;
		memcpy(&tx[2], &mcp->cache[MCP_IPOL], sizeof(tx) - 2);
		status = spi_write_then_read(mcp->spi, tx, sizeof tx, NULL, 0);
		if (status < 0)
			goto fail;
	}

	status = gpiochip_add(&mcp->chip);
fail:
	if (status < 0)
		dev_dbg(&spi->dev, "can't setup chip %d, --> %d\n",
				addr, status);
	return status;
}

static int mcp23s08_probe(struct spi_device *spi)
{
	struct mcp23s08_platform_data	*pdata;
	unsigned			addr;
	unsigned			chips = 0;
	struct mcp23s08_driver_data	*data;
	int				status;
	unsigned			base;

	pdata = spi->dev.platform_data;
	if (!pdata || !gpio_is_valid(pdata->base)) {
		dev_dbg(&spi->dev, "invalid or missing platform data\n");
		return -EINVAL;
	}

	for (addr = 0; addr < 4; addr++) {
		if (!pdata->chip[addr].is_present)
			continue;
		chips++;
	}
	if (!chips)
		return -ENODEV;

	data = kzalloc(sizeof *data + chips * sizeof(struct mcp23s08),
			GFP_KERNEL);
	if (!data)
		return -ENOMEM;
	spi_set_drvdata(spi, data);

	base = pdata->base;
	for (addr = 0; addr < 4; addr++) {
		if (!pdata->chip[addr].is_present)
			continue;
		chips--;
		data->mcp[addr] = &data->chip[chips];
		status = mcp23s08_probe_one(spi, addr, base,
				pdata->chip[addr].pullups);
		if (status < 0)
			goto fail;
		base += 8;
	}
	data->ngpio = base - pdata->base;

	/* NOTE:  these chips have a relatively sane IRQ framework, with
	 * per-signal masking and level/edge triggering.  It's not yet
	 * handled here...
	 */

	if (pdata->setup) {
		status = pdata->setup(spi,
				pdata->base, data->ngpio,
				pdata->context);
		if (status < 0)
			dev_dbg(&spi->dev, "setup --> %d\n", status);
	}

	return 0;

fail:
	for (addr = 0; addr < 4; addr++) {
		int tmp;

		if (!data->mcp[addr])
			continue;
		tmp = gpiochip_remove(&data->mcp[addr]->chip);
		if (tmp < 0)
			dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
	}
	kfree(data);
	return status;
}

static int mcp23s08_remove(struct spi_device *spi)
{
	struct mcp23s08_driver_data	*data = spi_get_drvdata(spi);
	struct mcp23s08_platform_data	*pdata = spi->dev.platform_data;
	unsigned			addr;
	int				status = 0;

	if (pdata->teardown) {
		status = pdata->teardown(spi,
				pdata->base, data->ngpio,
				pdata->context);
		if (status < 0) {
			dev_err(&spi->dev, "%s --> %d\n", "teardown", status);
			return status;
		}
	}

	for (addr = 0; addr < 4; addr++) {
		int tmp;

		if (!data->mcp[addr])
			continue;

		tmp = gpiochip_remove(&data->mcp[addr]->chip);
		if (tmp < 0) {
			dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
			status = tmp;
		}
	}
	if (status == 0)
		kfree(data);
	return status;
}

static struct spi_driver mcp23s08_driver = {
	.probe		= mcp23s08_probe,
	.remove		= mcp23s08_remove,
	.driver = {
		.name	= "mcp23s08",
		.owner	= THIS_MODULE,
	},
};

/*----------------------------------------------------------------------*/

static int __init mcp23s08_init(void)
{
	return spi_register_driver(&mcp23s08_driver);
}
/* register after spi postcore initcall and before
 * subsys initcalls that may rely on these GPIOs
 */
subsys_initcall(mcp23s08_init);

static void __exit mcp23s08_exit(void)
{
	spi_unregister_driver(&mcp23s08_driver);
}
module_exit(mcp23s08_exit);

MODULE_LICENSE("GPL");
Commit	Line	Data
e58b9e27 DB	1	/*
	2	* mcp23s08.c - SPI gpio expander driver
	3	*/
	4
	5	#include <linux/kernel.h>
	6	#include <linux/device.h>
	7	#include <linux/workqueue.h>
	8	#include <linux/mutex.h>
	9
	10	#include <linux/spi/spi.h>
	11	#include <linux/spi/mcp23s08.h>
	12
	13	#include <asm/gpio.h>
	14
	15
	16	/* Registers are all 8 bits wide.
	17	*
	18	* The mcp23s17 has twice as many bits, and can be configured to work
	19	* with either 16 bit registers or with two adjacent 8 bit banks.
	20	*
	21	* Also, there are I2C versions of both chips.
	22	*/
	23	#define MCP_IODIR 0x00 /* init/reset: all ones */
	24	#define MCP_IPOL 0x01
	25	#define MCP_GPINTEN 0x02
	26	#define MCP_DEFVAL 0x03
	27	#define MCP_INTCON 0x04
	28	#define MCP_IOCON 0x05
	29	# define IOCON_SEQOP (1 << 5)
	30	# define IOCON_HAEN (1 << 3)
	31	# define IOCON_ODR (1 << 2)
	32	# define IOCON_INTPOL (1 << 1)
	33	#define MCP_GPPU 0x06
	34	#define MCP_INTF 0x07
	35	#define MCP_INTCAP 0x08
	36	#define MCP_GPIO 0x09
	37	#define MCP_OLAT 0x0a
	38
	39	struct mcp23s08 {
	40	struct spi_device *spi;
	41	u8 addr;
	42
8f1cc3b1	43	u8 cache[11];
e58b9e27 DB	44	/* lock protects the cached values */
e58b9e27 DB	45	struct mutex lock;
e58b9e27 DB	46
	47	struct gpio_chip chip;
	48
	49	struct work_struct work;
	50	};
	51
8f1cc3b1 DB	52	/* A given spi_device can represent up to four mcp23s08 chips
	53	* sharing the same chipselect but using different addresses
	54	* (e.g. chips #0 and #3 might be populated, but not #1 or $2).
	55	* Driver data holds all the per-chip data.
	56	*/
	57	struct mcp23s08_driver_data {
	58	unsigned ngpio;
	59	struct mcp23s08 *mcp[4];
	60	struct mcp23s08 chip[];
	61	};
	62
e58b9e27 DB	63	static int mcp23s08_read(struct mcp23s08 *mcp, unsigned reg)
	64	{
	65	u8 tx[2], rx[1];
	66	int status;
	67
	68	tx[0] = mcp->addr \| 0x01;
	69	tx[1] = reg;
	70	status = spi_write_then_read(mcp->spi, tx, sizeof tx, rx, sizeof rx);
	71	return (status < 0) ? status : rx[0];
	72	}
	73
	74	static int mcp23s08_write(struct mcp23s08 *mcp, unsigned reg, u8 val)
	75	{
	76	u8 tx[3];
	77
	78	tx[0] = mcp->addr;
	79	tx[1] = reg;
	80	tx[2] = val;
	81	return spi_write_then_read(mcp->spi, tx, sizeof tx, NULL, 0);
	82	}
	83
	84	static int
	85	mcp23s08_read_regs(struct mcp23s08 mcp, unsigned reg, u8 vals, unsigned n)
	86	{
	87	u8 tx[2];
	88
	89	if ((n + reg) > sizeof mcp->cache)
	90	return -EINVAL;
	91	tx[0] = mcp->addr \| 0x01;
	92	tx[1] = reg;
	93	return spi_write_then_read(mcp->spi, tx, sizeof tx, vals, n);
	94	}
	95
	96	/----------------------------------------------------------------------/
	97
	98	static int mcp23s08_direction_input(struct gpio_chip *chip, unsigned offset)
	99	{
	100	struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
	101	int status;
	102
	103	mutex_lock(&mcp->lock);
	104	mcp->cache[MCP_IODIR] \|= (1 << offset);
	105	status = mcp23s08_write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
	106	mutex_unlock(&mcp->lock);
	107	return status;
	108	}
	109
	110	static int mcp23s08_get(struct gpio_chip *chip, unsigned offset)
	111	{
	112	struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
	113	int status;
	114
	115	mutex_lock(&mcp->lock);
	116
	117	/* REVISIT reading this clears any IRQ ... */
	118	status = mcp23s08_read(mcp, MCP_GPIO);
	119	if (status < 0)
	120	status = 0;
	121	else {
	122	mcp->cache[MCP_GPIO] = status;
	123	status = !!(status & (1 << offset));
	124	}
	125	mutex_unlock(&mcp->lock);
	126	return status;
127	}
128
129	static int __mcp23s08_set(struct mcp23s08 *mcp, unsigned mask, int value)
130	{
131	u8 olat = mcp->cache[MCP_OLAT];
132
133	if (value)
134	olat \|= mask;
135	else
136	olat &= ~mask;
137	mcp->cache[MCP_OLAT] = olat;
138	return mcp23s08_write(mcp, MCP_OLAT, olat);
139	}
140
141	static void mcp23s08_set(struct gpio_chip *chip, unsigned offset, int value)
142	{
143	struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
144	u8 mask = 1 << offset;
145
146	mutex_lock(&mcp->lock);
147	__mcp23s08_set(mcp, mask, value);
148	mutex_unlock(&mcp->lock);
149	}
150
151	static int
152	mcp23s08_direction_output(struct gpio_chip *chip, unsigned offset, int value)
153	{
154	struct mcp23s08 *mcp = container_of(chip, struct mcp23s08, chip);
155	u8 mask = 1 << offset;
156	int status;
157
158	mutex_lock(&mcp->lock);
159	status = __mcp23s08_set(mcp, mask, value);
160	if (status == 0) {
161	mcp->cache[MCP_IODIR] &= ~mask;
162	status = mcp23s08_write(mcp, MCP_IODIR, mcp->cache[MCP_IODIR]);
163	}
164	mutex_unlock(&mcp->lock);
165	return status;
166	}
167
168	/----------------------------------------------------------------------/
169
170	#ifdef CONFIG_DEBUG_FS
171
172	#include <linux/seq_file.h>
173
174	/*
175	* This shows more info than the generic gpio dump code:
176	* pullups, deglitching, open drain drive.
177	*/
178	static void mcp23s08_dbg_show(struct seq_file s, struct gpio_chip chip)
179	{
180	struct mcp23s08 *mcp;
181	char bank;
1d1c1d9b	182	int t;
e58b9e27 DB	183	unsigned mask;
	184
	185	mcp = container_of(chip, struct mcp23s08, chip);
	186
	187	/* NOTE: we only handle one bank for now ... */
	188	bank = '0' + ((mcp->addr >> 1) & 0x3);
	189
	190	mutex_lock(&mcp->lock);
	191	t = mcp23s08_read_regs(mcp, 0, mcp->cache, sizeof mcp->cache);
	192	if (t < 0) {
	193	seq_printf(s, " I/O ERROR %d\n", t);
	194	goto done;
	195	}
	196
	197	for (t = 0, mask = 1; t < 8; t++, mask <<= 1) {
	198	const char *label;
	199
	200	label = gpiochip_is_requested(chip, t);
	201	if (!label)
	202	continue;
	203
	204	seq_printf(s, " gpio-%-3d P%c.%d (%-12s) %s %s %s",
	205	chip->base + t, bank, t, label,
	206	(mcp->cache[MCP_IODIR] & mask) ? "in " : "out",
	207	(mcp->cache[MCP_GPIO] & mask) ? "hi" : "lo",
	208	(mcp->cache[MCP_GPPU] & mask) ? " " : "up");
	209	/* NOTE: ignoring the irq-related registers */
	210	seq_printf(s, "\n");
	211	}
	212	done:
	213	mutex_unlock(&mcp->lock);
	214	}
	215
	216	#else
	217	#define mcp23s08_dbg_show NULL
	218	#endif
	219
	220	/----------------------------------------------------------------------/
	221
8f1cc3b1 DB	222	static int mcp23s08_probe_one(struct spi_device *spi, unsigned addr,
8f1cc3b1 DB	223	unsigned base, unsigned pullups)
e58b9e27	224	{
8f1cc3b1 DB	225	struct mcp23s08_driver_data *data = spi_get_drvdata(spi);
8f1cc3b1 DB	226	struct mcp23s08 *mcp = data->mcp[addr];
e58b9e27 DB	227	int status;
	228	int do_update = 0;
	229
e58b9e27 DB	230	mutex_init(&mcp->lock);
	231
	232	mcp->spi = spi;
8f1cc3b1	233	mcp->addr = 0x40 \| (addr << 1);
e58b9e27 DB	234
	235	mcp->chip.label = "mcp23s08",
	236
	237	mcp->chip.direction_input = mcp23s08_direction_input;
	238	mcp->chip.get = mcp23s08_get;
	239	mcp->chip.direction_output = mcp23s08_direction_output;
	240	mcp->chip.set = mcp23s08_set;
	241	mcp->chip.dbg_show = mcp23s08_dbg_show;
	242
8f1cc3b1	243	mcp->chip.base = base;
e58b9e27 DB	244	mcp->chip.ngpio = 8;
e58b9e27 DB	245	mcp->chip.can_sleep = 1;
d8f388d8	246	mcp->chip.dev = &spi->dev;
d72cbed0	247	mcp->chip.owner = THIS_MODULE;
e58b9e27	248
8f1cc3b1 DB	249	/* verify MCP_IOCON.SEQOP = 0, so sequential reads work,
	250	* and MCP_IOCON.HAEN = 1, so we work with all chips.
	251	*/
e58b9e27 DB	252	status = mcp23s08_read(mcp, MCP_IOCON);
	253	if (status < 0)
	254	goto fail;
8f1cc3b1	255	if ((status & IOCON_SEQOP) \|\| !(status & IOCON_HAEN)) {
e58b9e27	256	status &= ~IOCON_SEQOP;
8f1cc3b1	257	status \|= IOCON_HAEN;
e58b9e27 DB	258	status = mcp23s08_write(mcp, MCP_IOCON, (u8) status);
	259	if (status < 0)
	260	goto fail;
	261	}
	262
	263	/* configure ~100K pullups */
8f1cc3b1	264	status = mcp23s08_write(mcp, MCP_GPPU, pullups);
e58b9e27 DB	265	if (status < 0)
	266	goto fail;
	267
	268	status = mcp23s08_read_regs(mcp, 0, mcp->cache, sizeof mcp->cache);
	269	if (status < 0)
	270	goto fail;
	271
	272	/* disable inverter on input */
	273	if (mcp->cache[MCP_IPOL] != 0) {
	274	mcp->cache[MCP_IPOL] = 0;
	275	do_update = 1;
	276	}
	277
	278	/* disable irqs */
	279	if (mcp->cache[MCP_GPINTEN] != 0) {
	280	mcp->cache[MCP_GPINTEN] = 0;
	281	do_update = 1;
	282	}
	283
	284	if (do_update) {
	285	u8 tx[4];
	286
	287	tx[0] = mcp->addr;
	288	tx[1] = MCP_IPOL;
	289	memcpy(&tx[2], &mcp->cache[MCP_IPOL], sizeof(tx) - 2);
	290	status = spi_write_then_read(mcp->spi, tx, sizeof tx, NULL, 0);
8f1cc3b1 DB	291	if (status < 0)
8f1cc3b1 DB	292	goto fail;
e58b9e27 DB	293	}
	294
	295	status = gpiochip_add(&mcp->chip);
8f1cc3b1 DB	296	fail:
	297	if (status < 0)
	298	dev_dbg(&spi->dev, "can't setup chip %d, --> %d\n",
	299	addr, status);
	300	return status;
	301	}
	302
	303	static int mcp23s08_probe(struct spi_device *spi)
	304	{
	305	struct mcp23s08_platform_data *pdata;
	306	unsigned addr;
	307	unsigned chips = 0;
	308	struct mcp23s08_driver_data *data;
	309	int status;
	310	unsigned base;
	311
	312	pdata = spi->dev.platform_data;
a342d215 BD	313	if (!pdata \|\| !gpio_is_valid(pdata->base)) {
	314	dev_dbg(&spi->dev, "invalid or missing platform data\n");
	315	return -EINVAL;
	316	}
8f1cc3b1 DB	317
	318	for (addr = 0; addr < 4; addr++) {
	319	if (!pdata->chip[addr].is_present)
	320	continue;
	321	chips++;
	322	}
	323	if (!chips)
	324	return -ENODEV;
	325
	326	data = kzalloc(sizeof data + chips sizeof(struct mcp23s08),
	327	GFP_KERNEL);
	328	if (!data)
	329	return -ENOMEM;
	330	spi_set_drvdata(spi, data);
	331
	332	base = pdata->base;
	333	for (addr = 0; addr < 4; addr++) {
	334	if (!pdata->chip[addr].is_present)
	335	continue;
	336	chips--;
	337	data->mcp[addr] = &data->chip[chips];
	338	status = mcp23s08_probe_one(spi, addr, base,
	339	pdata->chip[addr].pullups);
	340	if (status < 0)
	341	goto fail;
	342	base += 8;
	343	}
	344	data->ngpio = base - pdata->base;
e58b9e27 DB	345
	346	/* NOTE: these chips have a relatively sane IRQ framework, with
	347	* per-signal masking and level/edge triggering. It's not yet
	348	* handled here...
	349	*/
	350
	351	if (pdata->setup) {
8f1cc3b1 DB	352	status = pdata->setup(spi,
	353	pdata->base, data->ngpio,
	354	pdata->context);
e58b9e27 DB	355	if (status < 0)
	356	dev_dbg(&spi->dev, "setup --> %d\n", status);
	357	}
	358
	359	return 0;
	360
	361	fail:
8f1cc3b1 DB	362	for (addr = 0; addr < 4; addr++) {
	363	int tmp;
	364
	365	if (!data->mcp[addr])
	366	continue;
	367	tmp = gpiochip_remove(&data->mcp[addr]->chip);
	368	if (tmp < 0)
	369	dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
	370	}
	371	kfree(data);
e58b9e27 DB	372	return status;
	373	}
	374
	375	static int mcp23s08_remove(struct spi_device *spi)
	376	{
8f1cc3b1	377	struct mcp23s08_driver_data *data = spi_get_drvdata(spi);
e58b9e27	378	struct mcp23s08_platform_data *pdata = spi->dev.platform_data;
8f1cc3b1	379	unsigned addr;
e58b9e27 DB	380	int status = 0;
	381
	382	if (pdata->teardown) {
	383	status = pdata->teardown(spi,
8f1cc3b1	384	pdata->base, data->ngpio,
e58b9e27 DB	385	pdata->context);
	386	if (status < 0) {
	387	dev_err(&spi->dev, "%s --> %d\n", "teardown", status);
	388	return status;
	389	}
	390	}
	391
8f1cc3b1 DB	392	for (addr = 0; addr < 4; addr++) {
	393	int tmp;
	394
	395	if (!data->mcp[addr])
	396	continue;
	397
	398	tmp = gpiochip_remove(&data->mcp[addr]->chip);
	399	if (tmp < 0) {
	400	dev_err(&spi->dev, "%s --> %d\n", "remove", tmp);
	401	status = tmp;
	402	}
	403	}
e58b9e27	404	if (status == 0)
8f1cc3b1	405	kfree(data);
e58b9e27 DB	406	return status;
	407	}
	408
	409	static struct spi_driver mcp23s08_driver = {
	410	.probe = mcp23s08_probe,
	411	.remove = mcp23s08_remove,
	412	.driver = {
	413	.name = "mcp23s08",
	414	.owner = THIS_MODULE,
	415	},
	416	};
	417
	418	/----------------------------------------------------------------------/
	419
	420	static int __init mcp23s08_init(void)
	421	{
	422	return spi_register_driver(&mcp23s08_driver);
	423	}
673c0c00 DB	424	/* register after spi postcore initcall and before
	425	* subsys initcalls that may rely on these GPIOs
	426	*/
	427	subsys_initcall(mcp23s08_init);
e58b9e27 DB	428
	429	static void __exit mcp23s08_exit(void)
	430	{
	431	spi_unregister_driver(&mcp23s08_driver);
	432	}
	433	module_exit(mcp23s08_exit);
	434
	435	MODULE_LICENSE("GPL");