From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/arm/mach-u300/dummyspichip.c | 277 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 277 insertions(+) create mode 100644 arch/arm/mach-u300/dummyspichip.c (limited to 'arch/arm/mach-u300/dummyspichip.c') diff --git a/arch/arm/mach-u300/dummyspichip.c b/arch/arm/mach-u300/dummyspichip.c new file mode 100644 index 000000000..131996805 --- /dev/null +++ b/arch/arm/mach-u300/dummyspichip.c @@ -0,0 +1,277 @@ +/* + * 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 + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +/* + * 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 + +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 "); +MODULE_DESCRIPTION("PL022 SSP/SPI DUMMY Linux driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3-54-g00ecf