[deliverable/linux.git] / arch / arm / mach-u300 / dummyspichip.c

/*
 * arch/arm/mach-u300/dummyspichip.c
 *
 * Copyright (C) 2007-2009 ST-Ericsson AB
 * License terms: GNU General Public License (GPL) version 2
 * This is a dummy loopback SPI "chip" used for testing SPI.
 * Author: Linus Walleij <linus.walleij@stericsson.com>
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/sysfs.h>
#include <linux/mutex.h>
#include <linux/spi/spi.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
/*
 * WARNING! Do not include this pl022-specific controller header
 * for any generic driver. It is only done in this dummy chip
 * because we alter the chip configuration in order to test some
 * different settings on the loopback device. Normal chip configs
 * shall be STATIC and not altered by the driver!
 */
#include <linux/amba/pl022.h>

struct dummy {
	struct device *dev;
	struct mutex lock;
};

#define DMA_TEST_SIZE 2048

/* When we cat /sys/bus/spi/devices/spi0.0/looptest this will be triggered */
static ssize_t dummy_looptest(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct spi_device *spi = to_spi_device(dev);
	struct dummy *p_dummy = dev_get_drvdata(&spi->dev);

	/*
	 * WARNING! Do not dereference the chip-specific data in any normal
	 * driver for a chip. It is usually STATIC and shall not be read
	 * or written to. Your chip driver should NOT depend on fields in this
	 * struct, this is just used here to alter the behaviour of the chip
	 * in order to perform tests.
	 */
	int status;
	u8 txbuf[14] = {0xDE, 0xAD, 0xBE, 0xEF, 0x2B, 0xAD,
			0xCA, 0xFE, 0xBA, 0xBE, 0xB1, 0x05,
			0xF0, 0x0D};
	u8 rxbuf[14];
	u8 *bigtxbuf_virtual;
	u8 *bigrxbuf_virtual;

	if (mutex_lock_interruptible(&p_dummy->lock))
		return -ERESTARTSYS;

	bigtxbuf_virtual = kmalloc(DMA_TEST_SIZE, GFP_KERNEL);
	if (bigtxbuf_virtual == NULL) {
		status = -ENOMEM;
		goto out;
	}
	bigrxbuf_virtual = kmalloc(DMA_TEST_SIZE, GFP_KERNEL);

	/* Fill TXBUF with some happy pattern */
	memset(bigtxbuf_virtual, 0xAA, DMA_TEST_SIZE);

	/*
	 * Force chip to 8 bit mode
	 * WARNING: NEVER DO THIS IN REAL DRIVER CODE, THIS SHOULD BE STATIC!
	 */
	spi->bits_per_word = 8;
	/* You should NOT DO THIS EITHER */
	spi->master->setup(spi);

	/* Now run the tests for 8bit mode */
	pr_info("Simple test 1: write 0xAA byte, read back garbage byte "
		"in 8bit mode\n");
	status = spi_w8r8(spi, 0xAA);
	if (status < 0)
		pr_warn("Simple test 1: FAILURE: spi_write_then_read failed with status %d\n",
			status);
	else
		pr_info("Simple test 1: SUCCESS!\n");

	pr_info("Simple test 2: write 8 bytes, read back 8 bytes garbage "
		"in 8bit mode (full FIFO)\n");
	status = spi_write_then_read(spi, &txbuf[0], 8, &rxbuf[0], 8);
	if (status < 0)
		pr_warn("Simple test 2: FAILURE: spi_write_then_read() failed with status %d\n",
			status);
	else
		pr_info("Simple test 2: SUCCESS!\n");

	pr_info("Simple test 3: write 14 bytes, read back 14 bytes garbage "
		"in 8bit mode (see if we overflow FIFO)\n");
	status = spi_write_then_read(spi, &txbuf[0], 14, &rxbuf[0], 14);
	if (status < 0)
		pr_warn("Simple test 3: FAILURE: failed with status %d (probably FIFO overrun)\n",
			status);
	else
		pr_info("Simple test 3: SUCCESS!\n");

	pr_info("Simple test 4: write 8 bytes with spi_write(), read 8 "
		"bytes garbage with spi_read() in 8bit mode\n");
	status = spi_write(spi, &txbuf[0], 8);
	if (status < 0)
		pr_warn("Simple test 4 step 1: FAILURE: spi_write() failed with status %d\n",
			status);
	else
		pr_info("Simple test 4 step 1: SUCCESS!\n");
	status = spi_read(spi, &rxbuf[0], 8);
	if (status < 0)
		pr_warn("Simple test 4 step 2: FAILURE: spi_read() failed with status %d\n",
			status);
	else
		pr_info("Simple test 4 step 2: SUCCESS!\n");

	pr_info("Simple test 5: write 14 bytes with spi_write(), read "
		"14 bytes garbage with spi_read() in 8bit mode\n");
	status = spi_write(spi, &txbuf[0], 14);
	if (status < 0)
		pr_warn("Simple test 5 step 1: FAILURE: spi_write() failed with status %d (probably FIFO overrun)\n",
			status);
	else
		pr_info("Simple test 5 step 1: SUCCESS!\n");
	status = spi_read(spi, &rxbuf[0], 14);
	if (status < 0)
		pr_warn("Simple test 5 step 2: FAILURE: spi_read() failed with status %d (probably FIFO overrun)\n",
			status);
	else
		pr_info("Simple test 5: SUCCESS!\n");

	pr_info("Simple test 6: write %d bytes with spi_write(), "
		"read %d bytes garbage with spi_read() in 8bit mode\n",
		DMA_TEST_SIZE, DMA_TEST_SIZE);
	status = spi_write(spi, &bigtxbuf_virtual[0], DMA_TEST_SIZE);
	if (status < 0)
		pr_warn("Simple test 6 step 1: FAILURE: spi_write() failed with status %d (probably FIFO overrun)\n",
			status);
	else
		pr_info("Simple test 6 step 1: SUCCESS!\n");
	status = spi_read(spi, &bigrxbuf_virtual[0], DMA_TEST_SIZE);
	if (status < 0)
		pr_warn("Simple test 6 step 2: FAILURE: spi_read() failed with status %d (probably FIFO overrun)\n",
			status);
	else
		pr_info("Simple test 6: SUCCESS!\n");


	/*
	 * Force chip to 16 bit mode
	 * WARNING: NEVER DO THIS IN REAL DRIVER CODE, THIS SHOULD BE STATIC!
	 */
	spi->bits_per_word = 16;
	/* You should NOT DO THIS EITHER */
	spi->master->setup(spi);

	pr_info("Simple test 7: write 0xAA byte, read back garbage byte "
		"in 16bit bus mode\n");
	status = spi_w8r8(spi, 0xAA);
	if (status == -EIO)
		pr_info("Simple test 7: SUCCESS! (expected failure with "
			"status EIO)\n");
	else if (status < 0)
		pr_warn("Simple test 7: FAILURE: spi_write_then_read failed with status %d\n",
			status);
	else
		pr_warn("Simple test 7: FAILURE: spi_write_then_read succeeded but it was expected to fail!\n");

	pr_info("Simple test 8: write 8 bytes, read back 8 bytes garbage "
		"in 16bit mode (full FIFO)\n");
	status = spi_write_then_read(spi, &txbuf[0], 8, &rxbuf[0], 8);
	if (status < 0)
		pr_warn("Simple test 8: FAILURE: spi_write_then_read() failed with status %d\n",
			status);
	else
		pr_info("Simple test 8: SUCCESS!\n");

	pr_info("Simple test 9: write 14 bytes, read back 14 bytes garbage "
		"in 16bit mode (see if we overflow FIFO)\n");
	status = spi_write_then_read(spi, &txbuf[0], 14, &rxbuf[0], 14);
	if (status < 0)
		pr_warn("Simple test 9: FAILURE: failed with status %d (probably FIFO overrun)\n",
			status);
	else
		pr_info("Simple test 9: SUCCESS!\n");

	pr_info("Simple test 10: write %d bytes with spi_write(), "
	       "read %d bytes garbage with spi_read() in 16bit mode\n",
	       DMA_TEST_SIZE, DMA_TEST_SIZE);
	status = spi_write(spi, &bigtxbuf_virtual[0], DMA_TEST_SIZE);
	if (status < 0)
		pr_warn("Simple test 10 step 1: FAILURE: spi_write() failed with status %d (probably FIFO overrun)\n",
			status);
	else
		pr_info("Simple test 10 step 1: SUCCESS!\n");

	status = spi_read(spi, &bigrxbuf_virtual[0], DMA_TEST_SIZE);
	if (status < 0)
		pr_warn("Simple test 10 step 2: FAILURE: spi_read() failed with status %d (probably FIFO overrun)\n",
			status);
	else
		pr_info("Simple test 10: SUCCESS!\n");

	status = sprintf(buf, "loop test complete\n");
	kfree(bigrxbuf_virtual);
	kfree(bigtxbuf_virtual);
 out:
	mutex_unlock(&p_dummy->lock);
	return status;
}

static DEVICE_ATTR(looptest, S_IRUGO, dummy_looptest, NULL);

static int pl022_dummy_probe(struct spi_device *spi)
{
	struct dummy *p_dummy;
	int status;

	dev_info(&spi->dev, "probing dummy SPI device\n");

	p_dummy = kzalloc(sizeof *p_dummy, GFP_KERNEL);
	if (!p_dummy)
		return -ENOMEM;

	dev_set_drvdata(&spi->dev, p_dummy);
	mutex_init(&p_dummy->lock);

	/* sysfs hook */
	status = device_create_file(&spi->dev, &dev_attr_looptest);
	if (status) {
		dev_dbg(&spi->dev, "device_create_file looptest failure.\n");
		goto out_dev_create_looptest_failed;
	}

	return 0;

out_dev_create_looptest_failed:
	dev_set_drvdata(&spi->dev, NULL);
	kfree(p_dummy);
	return status;
}

static int pl022_dummy_remove(struct spi_device *spi)
{
	struct dummy *p_dummy = dev_get_drvdata(&spi->dev);

	dev_info(&spi->dev, "removing dummy SPI device\n");
	device_remove_file(&spi->dev, &dev_attr_looptest);
	dev_set_drvdata(&spi->dev, NULL);
	kfree(p_dummy);

	return 0;
}

static const struct of_device_id pl022_dummy_dt_match[] = {
	{ .compatible = "arm,pl022-dummy" },
	{},
};

static struct spi_driver pl022_dummy_driver = {
	.driver = {
		.name	= "spi-dummy",
		.owner	= THIS_MODULE,
		.of_match_table = pl022_dummy_dt_match,
	},
	.probe	= pl022_dummy_probe,
	.remove	= pl022_dummy_remove,
};

module_spi_driver(pl022_dummy_driver);
MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
MODULE_DESCRIPTION("PL022 SSP/SPI DUMMY Linux driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
c7c8c78f LW	1	/*
	2	* arch/arm/mach-u300/dummyspichip.c
	3	*
	4	* Copyright (C) 2007-2009 ST-Ericsson AB
	5	* License terms: GNU General Public License (GPL) version 2
	6	* This is a dummy loopback SPI "chip" used for testing SPI.
	7	* Author: Linus Walleij <linus.walleij@stericsson.com>
	8	*/
	9	#include <linux/init.h>
	10	#include <linux/module.h>
	11	#include <linux/kernel.h>
	12	#include <linux/device.h>
	13	#include <linux/err.h>
	14	#include <linux/sysfs.h>
	15	#include <linux/mutex.h>
	16	#include <linux/spi/spi.h>
	17	#include <linux/dma-mapping.h>
5a0e3ad6	18	#include <linux/slab.h>
c7c8c78f LW	19	/*
	20	* WARNING! Do not include this pl022-specific controller header
	21	* for any generic driver. It is only done in this dummy chip
	22	* because we alter the chip configuration in order to test some
	23	* different settings on the loopback device. Normal chip configs
	24	* shall be STATIC and not altered by the driver!
	25	*/
	26	#include <linux/amba/pl022.h>
	27
	28	struct dummy {
	29	struct device *dev;
	30	struct mutex lock;
	31	};
	32
	33	#define DMA_TEST_SIZE 2048
	34
	35	/* When we cat /sys/bus/spi/devices/spi0.0/looptest this will be triggered */
	36	static ssize_t dummy_looptest(struct device *dev,
	37	struct device_attribute attr, char buf)
	38	{
	39	struct spi_device *spi = to_spi_device(dev);
	40	struct dummy *p_dummy = dev_get_drvdata(&spi->dev);
	41
	42	/*
	43	* WARNING! Do not dereference the chip-specific data in any normal
	44	* driver for a chip. It is usually STATIC and shall not be read
	45	* or written to. Your chip driver should NOT depend on fields in this
	46	* struct, this is just used here to alter the behaviour of the chip
	47	* in order to perform tests.
	48	*/
c7c8c78f LW	49	int status;
	50	u8 txbuf[14] = {0xDE, 0xAD, 0xBE, 0xEF, 0x2B, 0xAD,
	51	0xCA, 0xFE, 0xBA, 0xBE, 0xB1, 0x05,
	52	0xF0, 0x0D};
	53	u8 rxbuf[14];
	54	u8 *bigtxbuf_virtual;
	55	u8 *bigrxbuf_virtual;
	56
	57	if (mutex_lock_interruptible(&p_dummy->lock))
	58	return -ERESTARTSYS;
	59
	60	bigtxbuf_virtual = kmalloc(DMA_TEST_SIZE, GFP_KERNEL);
	61	if (bigtxbuf_virtual == NULL) {
	62	status = -ENOMEM;
	63	goto out;
	64	}
	65	bigrxbuf_virtual = kmalloc(DMA_TEST_SIZE, GFP_KERNEL);
	66
	67	/* Fill TXBUF with some happy pattern */
	68	memset(bigtxbuf_virtual, 0xAA, DMA_TEST_SIZE);
	69
	70	/*
	71	* Force chip to 8 bit mode
	72	* WARNING: NEVER DO THIS IN REAL DRIVER CODE, THIS SHOULD BE STATIC!
	73	*/
bde435a9	74	spi->bits_per_word = 8;
c7c8c78f LW	75	/* You should NOT DO THIS EITHER */
	76	spi->master->setup(spi);
	77
	78	/* Now run the tests for 8bit mode */
	79	pr_info("Simple test 1: write 0xAA byte, read back garbage byte "
	80	"in 8bit mode\n");
	81	status = spi_w8r8(spi, 0xAA);
	82	if (status < 0)
2197eb81 JP	83	pr_warn("Simple test 1: FAILURE: spi_write_then_read failed with status %d\n",
2197eb81 JP	84	status);
c7c8c78f LW	85	else
	86	pr_info("Simple test 1: SUCCESS!\n");
	87
	88	pr_info("Simple test 2: write 8 bytes, read back 8 bytes garbage "
	89	"in 8bit mode (full FIFO)\n");
	90	status = spi_write_then_read(spi, &txbuf[0], 8, &rxbuf[0], 8);
	91	if (status < 0)
2197eb81 JP	92	pr_warn("Simple test 2: FAILURE: spi_write_then_read() failed with status %d\n",
2197eb81 JP	93	status);
c7c8c78f LW	94	else
	95	pr_info("Simple test 2: SUCCESS!\n");
	96
	97	pr_info("Simple test 3: write 14 bytes, read back 14 bytes garbage "
	98	"in 8bit mode (see if we overflow FIFO)\n");
	99	status = spi_write_then_read(spi, &txbuf[0], 14, &rxbuf[0], 14);
	100	if (status < 0)
2197eb81 JP	101	pr_warn("Simple test 3: FAILURE: failed with status %d (probably FIFO overrun)\n",
2197eb81 JP	102	status);
c7c8c78f LW	103	else
	104	pr_info("Simple test 3: SUCCESS!\n");
	105
	106	pr_info("Simple test 4: write 8 bytes with spi_write(), read 8 "
	107	"bytes garbage with spi_read() in 8bit mode\n");
	108	status = spi_write(spi, &txbuf[0], 8);
	109	if (status < 0)
2197eb81 JP	110	pr_warn("Simple test 4 step 1: FAILURE: spi_write() failed with status %d\n",
2197eb81 JP	111	status);
c7c8c78f LW	112	else
	113	pr_info("Simple test 4 step 1: SUCCESS!\n");
	114	status = spi_read(spi, &rxbuf[0], 8);
	115	if (status < 0)
2197eb81 JP	116	pr_warn("Simple test 4 step 2: FAILURE: spi_read() failed with status %d\n",
2197eb81 JP	117	status);
c7c8c78f LW	118	else
	119	pr_info("Simple test 4 step 2: SUCCESS!\n");
	120
	121	pr_info("Simple test 5: write 14 bytes with spi_write(), read "
	122	"14 bytes garbage with spi_read() in 8bit mode\n");
	123	status = spi_write(spi, &txbuf[0], 14);
	124	if (status < 0)
2197eb81 JP	125	pr_warn("Simple test 5 step 1: FAILURE: spi_write() failed with status %d (probably FIFO overrun)\n",
2197eb81 JP	126	status);
c7c8c78f LW	127	else
	128	pr_info("Simple test 5 step 1: SUCCESS!\n");
	129	status = spi_read(spi, &rxbuf[0], 14);
	130	if (status < 0)
2197eb81 JP	131	pr_warn("Simple test 5 step 2: FAILURE: spi_read() failed with status %d (probably FIFO overrun)\n",
2197eb81 JP	132	status);
c7c8c78f LW	133	else
	134	pr_info("Simple test 5: SUCCESS!\n");
	135
	136	pr_info("Simple test 6: write %d bytes with spi_write(), "
	137	"read %d bytes garbage with spi_read() in 8bit mode\n",
	138	DMA_TEST_SIZE, DMA_TEST_SIZE);
	139	status = spi_write(spi, &bigtxbuf_virtual[0], DMA_TEST_SIZE);
	140	if (status < 0)
2197eb81 JP	141	pr_warn("Simple test 6 step 1: FAILURE: spi_write() failed with status %d (probably FIFO overrun)\n",
2197eb81 JP	142	status);
c7c8c78f LW	143	else
	144	pr_info("Simple test 6 step 1: SUCCESS!\n");
	145	status = spi_read(spi, &bigrxbuf_virtual[0], DMA_TEST_SIZE);
	146	if (status < 0)
2197eb81 JP	147	pr_warn("Simple test 6 step 2: FAILURE: spi_read() failed with status %d (probably FIFO overrun)\n",
2197eb81 JP	148	status);
c7c8c78f LW	149	else
	150	pr_info("Simple test 6: SUCCESS!\n");
	151
	152
	153	/*
	154	* Force chip to 16 bit mode
	155	* WARNING: NEVER DO THIS IN REAL DRIVER CODE, THIS SHOULD BE STATIC!
	156	*/
bde435a9	157	spi->bits_per_word = 16;
c7c8c78f LW	158	/* You should NOT DO THIS EITHER */
	159	spi->master->setup(spi);
	160
	161	pr_info("Simple test 7: write 0xAA byte, read back garbage byte "
	162	"in 16bit bus mode\n");
	163	status = spi_w8r8(spi, 0xAA);
	164	if (status == -EIO)
	165	pr_info("Simple test 7: SUCCESS! (expected failure with "
	166	"status EIO)\n");
	167	else if (status < 0)
2197eb81 JP	168	pr_warn("Simple test 7: FAILURE: spi_write_then_read failed with status %d\n",
2197eb81 JP	169	status);
c7c8c78f	170	else
2197eb81	171	pr_warn("Simple test 7: FAILURE: spi_write_then_read succeeded but it was expected to fail!\n");
c7c8c78f LW	172
	173	pr_info("Simple test 8: write 8 bytes, read back 8 bytes garbage "
	174	"in 16bit mode (full FIFO)\n");
	175	status = spi_write_then_read(spi, &txbuf[0], 8, &rxbuf[0], 8);
	176	if (status < 0)
2197eb81 JP	177	pr_warn("Simple test 8: FAILURE: spi_write_then_read() failed with status %d\n",
2197eb81 JP	178	status);
c7c8c78f LW	179	else
	180	pr_info("Simple test 8: SUCCESS!\n");
	181
	182	pr_info("Simple test 9: write 14 bytes, read back 14 bytes garbage "
	183	"in 16bit mode (see if we overflow FIFO)\n");
	184	status = spi_write_then_read(spi, &txbuf[0], 14, &rxbuf[0], 14);
	185	if (status < 0)
2197eb81 JP	186	pr_warn("Simple test 9: FAILURE: failed with status %d (probably FIFO overrun)\n",
2197eb81 JP	187	status);
c7c8c78f LW	188	else
	189	pr_info("Simple test 9: SUCCESS!\n");
	190
	191	pr_info("Simple test 10: write %d bytes with spi_write(), "
	192	"read %d bytes garbage with spi_read() in 16bit mode\n",
	193	DMA_TEST_SIZE, DMA_TEST_SIZE);
	194	status = spi_write(spi, &bigtxbuf_virtual[0], DMA_TEST_SIZE);
	195	if (status < 0)
2197eb81 JP	196	pr_warn("Simple test 10 step 1: FAILURE: spi_write() failed with status %d (probably FIFO overrun)\n",
2197eb81 JP	197	status);
c7c8c78f LW	198	else
	199	pr_info("Simple test 10 step 1: SUCCESS!\n");
	200
	201	status = spi_read(spi, &bigrxbuf_virtual[0], DMA_TEST_SIZE);
	202	if (status < 0)
2197eb81 JP	203	pr_warn("Simple test 10 step 2: FAILURE: spi_read() failed with status %d (probably FIFO overrun)\n",
2197eb81 JP	204	status);
c7c8c78f LW	205	else
	206	pr_info("Simple test 10: SUCCESS!\n");
	207
	208	status = sprintf(buf, "loop test complete\n");
	209	kfree(bigrxbuf_virtual);
	210	kfree(bigtxbuf_virtual);
	211	out:
	212	mutex_unlock(&p_dummy->lock);
	213	return status;
	214	}
	215
	216	static DEVICE_ATTR(looptest, S_IRUGO, dummy_looptest, NULL);
	217
351a102d	218	static int pl022_dummy_probe(struct spi_device *spi)
c7c8c78f LW	219	{
	220	struct dummy *p_dummy;
	221	int status;
	222
	223	dev_info(&spi->dev, "probing dummy SPI device\n");
	224
	225	p_dummy = kzalloc(sizeof *p_dummy, GFP_KERNEL);
	226	if (!p_dummy)
	227	return -ENOMEM;
	228
	229	dev_set_drvdata(&spi->dev, p_dummy);
	230	mutex_init(&p_dummy->lock);
	231
	232	/* sysfs hook */
	233	status = device_create_file(&spi->dev, &dev_attr_looptest);
	234	if (status) {
	235	dev_dbg(&spi->dev, "device_create_file looptest failure.\n");
	236	goto out_dev_create_looptest_failed;
	237	}
	238
	239	return 0;
	240
	241	out_dev_create_looptest_failed:
	242	dev_set_drvdata(&spi->dev, NULL);
	243	kfree(p_dummy);
	244	return status;
	245	}
	246
351a102d	247	static int pl022_dummy_remove(struct spi_device *spi)
c7c8c78f LW	248	{
	249	struct dummy *p_dummy = dev_get_drvdata(&spi->dev);
	250
	251	dev_info(&spi->dev, "removing dummy SPI device\n");
	252	device_remove_file(&spi->dev, &dev_attr_looptest);
	253	dev_set_drvdata(&spi->dev, NULL);
	254	kfree(p_dummy);
	255
	256	return 0;
	257	}
	258
20d4af68 LW	259	static const struct of_device_id pl022_dummy_dt_match[] = {
	260	{ .compatible = "arm,pl022-dummy" },
	261	{},
	262	};
	263
c7c8c78f LW	264	static struct spi_driver pl022_dummy_driver = {
	265	.driver = {
	266	.name = "spi-dummy",
	267	.owner = THIS_MODULE,
20d4af68	268	.of_match_table = pl022_dummy_dt_match,
c7c8c78f LW	269	},
c7c8c78f LW	270	.probe = pl022_dummy_probe,
351a102d	271	.remove = pl022_dummy_remove,
c7c8c78f LW	272	};
c7c8c78f LW	273
be2885a5	274	module_spi_driver(pl022_dummy_driver);
c7c8c78f LW	275	MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
	276	MODULE_DESCRIPTION("PL022 SSP/SPI DUMMY Linux driver");
	277	MODULE_LICENSE("GPL");