diff options
Diffstat (limited to 'kernel/drivers/misc/eeprom')
| -rw-r--r-- | kernel/drivers/misc/eeprom/Kconfig | 112 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/Makefile | 8 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/at24.c | 719 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/at25.c | 477 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/digsy_mtc_eeprom.c | 85 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/eeprom.c | 226 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/eeprom_93cx6.c | 381 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/eeprom_93xx46.c | 398 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/max6875.c | 214 | ||||
| -rw-r--r-- | kernel/drivers/misc/eeprom/sunxi_sid.c | 156 |
10 files changed, 2776 insertions, 0 deletions
diff --git a/kernel/drivers/misc/eeprom/Kconfig b/kernel/drivers/misc/eeprom/Kconfig new file mode 100644 index 000000000..9536852fd --- /dev/null +++ b/kernel/drivers/misc/eeprom/Kconfig @@ -0,0 +1,112 @@ +menu "EEPROM support" + +config EEPROM_AT24 + tristate "I2C EEPROMs / RAMs / ROMs from most vendors" + depends on I2C && SYSFS + help + Enable this driver to get read/write support to most I2C EEPROMs + and compatible devices like FRAMs, SRAMs, ROMs etc. After you + configure the driver to know about each chip on your target + board. Use these generic chip names, instead of vendor-specific + ones like at24c64, 24lc02 or fm24c04: + + 24c00, 24c01, 24c02, spd (readonly 24c02), 24c04, 24c08, + 24c16, 24c32, 24c64, 24c128, 24c256, 24c512, 24c1024 + + Unless you like data loss puzzles, always be sure that any chip + you configure as a 24c32 (32 kbit) or larger is NOT really a + 24c16 (16 kbit) or smaller, and vice versa. Marking the chip + as read-only won't help recover from this. Also, if your chip + has any software write-protect mechanism you may want to review the + code to make sure this driver won't turn it on by accident. + + If you use this with an SMBus adapter instead of an I2C adapter, + full functionality is not available. Only smaller devices are + supported (24c16 and below, max 4 kByte). + + This driver can also be built as a module. If so, the module + will be called at24. + +config EEPROM_AT25 + tristate "SPI EEPROMs from most vendors" + depends on SPI && SYSFS + help + Enable this driver to get read/write support to most SPI EEPROMs, + after you configure the board init code to know about each eeprom + on your target board. + + This driver can also be built as a module. If so, the module + will be called at25. + +config EEPROM_LEGACY + tristate "Old I2C EEPROM reader" + depends on I2C && SYSFS + help + If you say yes here you get read-only access to the EEPROM data + available on modern memory DIMMs and Sony Vaio laptops via I2C. Such + EEPROMs could theoretically be available on other devices as well. + + This driver can also be built as a module. If so, the module + will be called eeprom. + +config EEPROM_MAX6875 + tristate "Maxim MAX6874/5 power supply supervisor" + depends on I2C + help + If you say yes here you get read-only support for the user EEPROM of + the Maxim MAX6874/5 EEPROM-programmable, quad power-supply + sequencer/supervisor. + + All other features of this chip should be accessed via i2c-dev. + + This driver can also be built as a module. If so, the module + will be called max6875. + + +config EEPROM_93CX6 + tristate "EEPROM 93CX6 support" + help + This is a driver for the EEPROM chipsets 93c46 and 93c66. + The driver supports both read as well as write commands. + + If unsure, say N. + +config EEPROM_93XX46 + tristate "Microwire EEPROM 93XX46 support" + depends on SPI && SYSFS + help + Driver for the microwire EEPROM chipsets 93xx46x. The driver + supports both read and write commands and also the command to + erase the whole EEPROM. + + This driver can also be built as a module. If so, the module + will be called eeprom_93xx46. + + If unsure, say N. + +config EEPROM_DIGSY_MTC_CFG + bool "DigsyMTC display configuration EEPROMs device" + depends on GPIO_MPC5200 && SPI_GPIO + help + This option enables access to display configuration EEPROMs + on digsy_mtc board. You have to additionally select Microwire + EEPROM 93XX46 driver. sysfs entries will be created for that + EEPROM allowing to read/write the configuration data or to + erase the whole EEPROM. + + If unsure, say N. + +config EEPROM_SUNXI_SID + tristate "Allwinner sunxi security ID support" + depends on ARCH_SUNXI && SYSFS + help + This is a driver for the 'security ID' available on various Allwinner + devices. + + Due to the potential risks involved with changing e-fuses, + this driver is read-only. + + This driver can also be built as a module. If so, the module + will be called sunxi_sid. + +endmenu diff --git a/kernel/drivers/misc/eeprom/Makefile b/kernel/drivers/misc/eeprom/Makefile new file mode 100644 index 000000000..9507aec95 --- /dev/null +++ b/kernel/drivers/misc/eeprom/Makefile @@ -0,0 +1,8 @@ +obj-$(CONFIG_EEPROM_AT24) += at24.o +obj-$(CONFIG_EEPROM_AT25) += at25.o +obj-$(CONFIG_EEPROM_LEGACY) += eeprom.o +obj-$(CONFIG_EEPROM_MAX6875) += max6875.o +obj-$(CONFIG_EEPROM_93CX6) += eeprom_93cx6.o +obj-$(CONFIG_EEPROM_93XX46) += eeprom_93xx46.o +obj-$(CONFIG_EEPROM_SUNXI_SID) += sunxi_sid.o +obj-$(CONFIG_EEPROM_DIGSY_MTC_CFG) += digsy_mtc_eeprom.o diff --git a/kernel/drivers/misc/eeprom/at24.c b/kernel/drivers/misc/eeprom/at24.c new file mode 100644 index 000000000..2d3db81be --- /dev/null +++ b/kernel/drivers/misc/eeprom/at24.c @@ -0,0 +1,719 @@ +/* + * at24.c - handle most I2C EEPROMs + * + * Copyright (C) 2005-2007 David Brownell + * Copyright (C) 2008 Wolfram Sang, Pengutronix + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/mutex.h> +#include <linux/sysfs.h> +#include <linux/mod_devicetable.h> +#include <linux/log2.h> +#include <linux/bitops.h> +#include <linux/jiffies.h> +#include <linux/of.h> +#include <linux/i2c.h> +#include <linux/platform_data/at24.h> + +/* + * I2C EEPROMs from most vendors are inexpensive and mostly interchangeable. + * Differences between different vendor product lines (like Atmel AT24C or + * MicroChip 24LC, etc) won't much matter for typical read/write access. + * There are also I2C RAM chips, likewise interchangeable. One example + * would be the PCF8570, which acts like a 24c02 EEPROM (256 bytes). + * + * However, misconfiguration can lose data. "Set 16-bit memory address" + * to a part with 8-bit addressing will overwrite data. Writing with too + * big a page size also loses data. And it's not safe to assume that the + * conventional addresses 0x50..0x57 only hold eeproms; a PCF8563 RTC + * uses 0x51, for just one example. + * + * Accordingly, explicit board-specific configuration data should be used + * in almost all cases. (One partial exception is an SMBus used to access + * "SPD" data for DRAM sticks. Those only use 24c02 EEPROMs.) + * + * So this driver uses "new style" I2C driver binding, expecting to be + * told what devices exist. That may be in arch/X/mach-Y/board-Z.c or + * similar kernel-resident tables; or, configuration data coming from + * a bootloader. + * + * Other than binding model, current differences from "eeprom" driver are + * that this one handles write access and isn't restricted to 24c02 devices. + * It also handles larger devices (32 kbit and up) with two-byte addresses, + * which won't work on pure SMBus systems. + */ + +struct at24_data { + struct at24_platform_data chip; + struct memory_accessor macc; + int use_smbus; + int use_smbus_write; + + /* + * Lock protects against activities from other Linux tasks, + * but not from changes by other I2C masters. + */ + struct mutex lock; + struct bin_attribute bin; + + u8 *writebuf; + unsigned write_max; + unsigned num_addresses; + + /* + * Some chips tie up multiple I2C addresses; dummy devices reserve + * them for us, and we'll use them with SMBus calls. + */ + struct i2c_client *client[]; +}; + +/* + * This parameter is to help this driver avoid blocking other drivers out + * of I2C for potentially troublesome amounts of time. With a 100 kHz I2C + * clock, one 256 byte read takes about 1/43 second which is excessive; + * but the 1/170 second it takes at 400 kHz may be quite reasonable; and + * at 1 MHz (Fm+) a 1/430 second delay could easily be invisible. + * + * This value is forced to be a power of two so that writes align on pages. + */ +static unsigned io_limit = 128; +module_param(io_limit, uint, 0); +MODULE_PARM_DESC(io_limit, "Maximum bytes per I/O (default 128)"); + +/* + * Specs often allow 5 msec for a page write, sometimes 20 msec; + * it's important to recover from write timeouts. + */ +static unsigned write_timeout = 25; +module_param(write_timeout, uint, 0); +MODULE_PARM_DESC(write_timeout, "Time (in ms) to try writes (default 25)"); + +#define AT24_SIZE_BYTELEN 5 +#define AT24_SIZE_FLAGS 8 + +#define AT24_BITMASK(x) (BIT(x) - 1) + +/* create non-zero magic value for given eeprom parameters */ +#define AT24_DEVICE_MAGIC(_len, _flags) \ + ((1 << AT24_SIZE_FLAGS | (_flags)) \ + << AT24_SIZE_BYTELEN | ilog2(_len)) + +static const struct i2c_device_id at24_ids[] = { + /* needs 8 addresses as A0-A2 are ignored */ + { "24c00", AT24_DEVICE_MAGIC(128 / 8, AT24_FLAG_TAKE8ADDR) }, + /* old variants can't be handled with this generic entry! */ + { "24c01", AT24_DEVICE_MAGIC(1024 / 8, 0) }, + { "24c02", AT24_DEVICE_MAGIC(2048 / 8, 0) }, + /* spd is a 24c02 in memory DIMMs */ + { "spd", AT24_DEVICE_MAGIC(2048 / 8, + AT24_FLAG_READONLY | AT24_FLAG_IRUGO) }, + { "24c04", AT24_DEVICE_MAGIC(4096 / 8, 0) }, + /* 24rf08 quirk is handled at i2c-core */ + { "24c08", AT24_DEVICE_MAGIC(8192 / 8, 0) }, + { "24c16", AT24_DEVICE_MAGIC(16384 / 8, 0) }, + { "24c32", AT24_DEVICE_MAGIC(32768 / 8, AT24_FLAG_ADDR16) }, + { "24c64", AT24_DEVICE_MAGIC(65536 / 8, AT24_FLAG_ADDR16) }, + { "24c128", AT24_DEVICE_MAGIC(131072 / 8, AT24_FLAG_ADDR16) }, + { "24c256", AT24_DEVICE_MAGIC(262144 / 8, AT24_FLAG_ADDR16) }, + { "24c512", AT24_DEVICE_MAGIC(524288 / 8, AT24_FLAG_ADDR16) }, + { "24c1024", AT24_DEVICE_MAGIC(1048576 / 8, AT24_FLAG_ADDR16) }, + { "at24", 0 }, + { /* END OF LIST */ } +}; +MODULE_DEVICE_TABLE(i2c, at24_ids); + +/*-------------------------------------------------------------------------*/ + +/* + * This routine supports chips which consume multiple I2C addresses. It + * computes the addressing information to be used for a given r/w request. + * Assumes that sanity checks for offset happened at sysfs-layer. + */ +static struct i2c_client *at24_translate_offset(struct at24_data *at24, + unsigned *offset) +{ + unsigned i; + + if (at24->chip.flags & AT24_FLAG_ADDR16) { + i = *offset >> 16; + *offset &= 0xffff; + } else { + i = *offset >> 8; + *offset &= 0xff; + } + + return at24->client[i]; +} + +static ssize_t at24_eeprom_read(struct at24_data *at24, char *buf, + unsigned offset, size_t count) +{ + struct i2c_msg msg[2]; + u8 msgbuf[2]; + struct i2c_client *client; + unsigned long timeout, read_time; + int status, i; + + memset(msg, 0, sizeof(msg)); + + /* + * REVISIT some multi-address chips don't rollover page reads to + * the next slave address, so we may need to truncate the count. + * Those chips might need another quirk flag. + * + * If the real hardware used four adjacent 24c02 chips and that + * were misconfigured as one 24c08, that would be a similar effect: + * one "eeprom" file not four, but larger reads would fail when + * they crossed certain pages. + */ + + /* + * Slave address and byte offset derive from the offset. Always + * set the byte address; on a multi-master board, another master + * may have changed the chip's "current" address pointer. + */ + client = at24_translate_offset(at24, &offset); + + if (count > io_limit) + count = io_limit; + + switch (at24->use_smbus) { + case I2C_SMBUS_I2C_BLOCK_DATA: + /* Smaller eeproms can work given some SMBus extension calls */ + if (count > I2C_SMBUS_BLOCK_MAX) + count = I2C_SMBUS_BLOCK_MAX; + break; + case I2C_SMBUS_WORD_DATA: + count = 2; + break; + case I2C_SMBUS_BYTE_DATA: + count = 1; + break; + default: + /* + * When we have a better choice than SMBus calls, use a + * combined I2C message. Write address; then read up to + * io_limit data bytes. Note that read page rollover helps us + * here (unlike writes). msgbuf is u8 and will cast to our + * needs. + */ + i = 0; + if (at24->chip.flags & AT24_FLAG_ADDR16) + msgbuf[i++] = offset >> 8; + msgbuf[i++] = offset; + + msg[0].addr = client->addr; + msg[0].buf = msgbuf; + msg[0].len = i; + + msg[1].addr = client->addr; + msg[1].flags = I2C_M_RD; + msg[1].buf = buf; + msg[1].len = count; + } + + /* + * Reads fail if the previous write didn't complete yet. We may + * loop a few times until this one succeeds, waiting at least + * long enough for one entire page write to work. + */ + timeout = jiffies + msecs_to_jiffies(write_timeout); + do { + read_time = jiffies; + switch (at24->use_smbus) { + case I2C_SMBUS_I2C_BLOCK_DATA: + status = i2c_smbus_read_i2c_block_data(client, offset, + count, buf); + break; + case I2C_SMBUS_WORD_DATA: + status = i2c_smbus_read_word_data(client, offset); + if (status >= 0) { + buf[0] = status & 0xff; + buf[1] = status >> 8; + status = count; + } + break; + case I2C_SMBUS_BYTE_DATA: + status = i2c_smbus_read_byte_data(client, offset); + if (status >= 0) { + buf[0] = status; + status = count; + } + break; + default: + status = i2c_transfer(client->adapter, msg, 2); + if (status == 2) + status = count; + } + dev_dbg(&client->dev, "read %zu@%d --> %d (%ld)\n", + count, offset, status, jiffies); + + if (status == count) + return count; + + /* REVISIT: at HZ=100, this is sloooow */ + msleep(1); + } while (time_before(read_time, timeout)); + + return -ETIMEDOUT; +} + +static ssize_t at24_read(struct at24_data *at24, + char *buf, loff_t off, size_t count) +{ + ssize_t retval = 0; + + if (unlikely(!count)) + return count; + + /* + * Read data from chip, protecting against concurrent updates + * from this host, but not from other I2C masters. + */ + mutex_lock(&at24->lock); + + while (count) { + ssize_t status; + + status = at24_eeprom_read(at24, buf, off, count); + if (status <= 0) { + if (retval == 0) + retval = status; + break; + } + buf += status; + off += status; + count -= status; + retval += status; + } + + mutex_unlock(&at24->lock); + + return retval; +} + +static ssize_t at24_bin_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, + char *buf, loff_t off, size_t count) +{ + struct at24_data *at24; + + at24 = dev_get_drvdata(container_of(kobj, struct device, kobj)); + return at24_read(at24, buf, off, count); +} + + +/* + * Note that if the hardware write-protect pin is pulled high, the whole + * chip is normally write protected. But there are plenty of product + * variants here, including OTP fuses and partial chip protect. + * + * We only use page mode writes; the alternative is sloooow. This routine + * writes at most one page. + */ +static ssize_t at24_eeprom_write(struct at24_data *at24, const char *buf, + unsigned offset, size_t count) +{ + struct i2c_client *client; + struct i2c_msg msg; + ssize_t status = 0; + unsigned long timeout, write_time; + unsigned next_page; + + /* Get corresponding I2C address and adjust offset */ + client = at24_translate_offset(at24, &offset); + + /* write_max is at most a page */ + if (count > at24->write_max) + count = at24->write_max; + + /* Never roll over backwards, to the start of this page */ + next_page = roundup(offset + 1, at24->chip.page_size); + if (offset + count > next_page) + count = next_page - offset; + + /* If we'll use I2C calls for I/O, set up the message */ + if (!at24->use_smbus) { + int i = 0; + + msg.addr = client->addr; + msg.flags = 0; + + /* msg.buf is u8 and casts will mask the values */ + msg.buf = at24->writebuf; + if (at24->chip.flags & AT24_FLAG_ADDR16) + msg.buf[i++] = offset >> 8; + + msg.buf[i++] = offset; + memcpy(&msg.buf[i], buf, count); + msg.len = i + count; + } + + /* + * Writes fail if the previous one didn't complete yet. We may + * loop a few times until this one succeeds, waiting at least + * long enough for one entire page write to work. + */ + timeout = jiffies + msecs_to_jiffies(write_timeout); + do { + write_time = jiffies; + if (at24->use_smbus_write) { + switch (at24->use_smbus_write) { + case I2C_SMBUS_I2C_BLOCK_DATA: + status = i2c_smbus_write_i2c_block_data(client, + offset, count, buf); + break; + case I2C_SMBUS_BYTE_DATA: + status = i2c_smbus_write_byte_data(client, + offset, buf[0]); + break; + } + + if (status == 0) + status = count; + } else { + status = i2c_transfer(client->adapter, &msg, 1); + if (status == 1) + status = count; + } + dev_dbg(&client->dev, "write %zu@%d --> %zd (%ld)\n", + count, offset, status, jiffies); + + if (status == count) + return count; + + /* REVISIT: at HZ=100, this is sloooow */ + msleep(1); + } while (time_before(write_time, timeout)); + + return -ETIMEDOUT; +} + +static ssize_t at24_write(struct at24_data *at24, const char *buf, loff_t off, + size_t count) +{ + ssize_t retval = 0; + + if (unlikely(!count)) + return count; + + /* + * Write data to chip, protecting against concurrent updates + * from this host, but not from other I2C masters. + */ + mutex_lock(&at24->lock); + + while (count) { + ssize_t status; + + status = at24_eeprom_write(at24, buf, off, count); + if (status <= 0) { + if (retval == 0) + retval = status; + break; + } + buf += status; + off += status; + count -= status; + retval += status; + } + + mutex_unlock(&at24->lock); + + return retval; +} + +static ssize_t at24_bin_write(struct file *filp, struct kobject *kobj, + struct bin_attribute *attr, + char *buf, loff_t off, size_t count) +{ + struct at24_data *at24; + + if (unlikely(off >= attr->size)) + return -EFBIG; + + at24 = dev_get_drvdata(container_of(kobj, struct device, kobj)); + return at24_write(at24, buf, off, count); +} + +/*-------------------------------------------------------------------------*/ + +/* + * This lets other kernel code access the eeprom data. For example, it + * might hold a board's Ethernet address, or board-specific calibration + * data generated on the manufacturing floor. + */ + +static ssize_t at24_macc_read(struct memory_accessor *macc, char *buf, + off_t offset, size_t count) +{ + struct at24_data *at24 = container_of(macc, struct at24_data, macc); + + return at24_read(at24, buf, offset, count); +} + +static ssize_t at24_macc_write(struct memory_accessor *macc, const char *buf, + off_t offset, size_t count) +{ + struct at24_data *at24 = container_of(macc, struct at24_data, macc); + + return at24_write(at24, buf, offset, count); +} + +/*-------------------------------------------------------------------------*/ + +#ifdef CONFIG_OF +static void at24_get_ofdata(struct i2c_client *client, + struct at24_platform_data *chip) +{ + const __be32 *val; + struct device_node *node = client->dev.of_node; + + if (node) { + if (of_get_property(node, "read-only", NULL)) + chip->flags |= AT24_FLAG_READONLY; + val = of_get_property(node, "pagesize", NULL); + if (val) + chip->page_size = be32_to_cpup(val); + } +} +#else +static void at24_get_ofdata(struct i2c_client *client, + struct at24_platform_data *chip) +{ } +#endif /* CONFIG_OF */ + +static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + struct at24_platform_data chip; + bool writable; + int use_smbus = 0; + int use_smbus_write = 0; + struct at24_data *at24; + int err; + unsigned i, num_addresses; + kernel_ulong_t magic; + + if (client->dev.platform_data) { + chip = *(struct at24_platform_data *)client->dev.platform_data; + } else { + if (!id->driver_data) + return -ENODEV; + + magic = id->driver_data; + chip.byte_len = BIT(magic & AT24_BITMASK(AT24_SIZE_BYTELEN)); + magic >>= AT24_SIZE_BYTELEN; + chip.flags = magic & AT24_BITMASK(AT24_SIZE_FLAGS); + /* + * This is slow, but we can't know all eeproms, so we better + * play safe. Specifying custom eeprom-types via platform_data + * is recommended anyhow. + */ + chip.page_size = 1; + + /* update chipdata if OF is present */ + at24_get_ofdata(client, &chip); + + chip.setup = NULL; + chip.context = NULL; + } + + if (!is_power_of_2(chip.byte_len)) + dev_warn(&client->dev, + "byte_len looks suspicious (no power of 2)!\n"); + if (!chip.page_size) { + dev_err(&client->dev, "page_size must not be 0!\n"); + return -EINVAL; + } + if (!is_power_of_2(chip.page_size)) + dev_warn(&client->dev, + "page_size looks suspicious (no power of 2)!\n"); + + /* Use I2C operations unless we're stuck with SMBus extensions. */ + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + if (chip.flags & AT24_FLAG_ADDR16) + return -EPFNOSUPPORT; + + if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { + use_smbus = I2C_SMBUS_I2C_BLOCK_DATA; + } else if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_WORD_DATA)) { + use_smbus = I2C_SMBUS_WORD_DATA; + } else if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_BYTE_DATA)) { + use_smbus = I2C_SMBUS_BYTE_DATA; + } else { + return -EPFNOSUPPORT; + } + } + + /* Use I2C operations unless we're stuck with SMBus extensions. */ + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) { + use_smbus_write = I2C_SMBUS_I2C_BLOCK_DATA; + } else if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) { + use_smbus_write = I2C_SMBUS_BYTE_DATA; + chip.page_size = 1; + } + } + + if (chip.flags & AT24_FLAG_TAKE8ADDR) + num_addresses = 8; + else + num_addresses = DIV_ROUND_UP(chip.byte_len, + (chip.flags & AT24_FLAG_ADDR16) ? 65536 : 256); + + at24 = devm_kzalloc(&client->dev, sizeof(struct at24_data) + + num_addresses * sizeof(struct i2c_client *), GFP_KERNEL); + if (!at24) + return -ENOMEM; + + mutex_init(&at24->lock); + at24->use_smbus = use_smbus; + at24->use_smbus_write = use_smbus_write; + at24->chip = chip; + at24->num_addresses = num_addresses; + + /* + * Export the EEPROM bytes through sysfs, since that's convenient. + * By default, only root should see the data (maybe passwords etc) + */ + sysfs_bin_attr_init(&at24->bin); + at24->bin.attr.name = "eeprom"; + at24->bin.attr.mode = chip.flags & AT24_FLAG_IRUGO ? S_IRUGO : S_IRUSR; + at24->bin.read = at24_bin_read; + at24->bin.size = chip.byte_len; + + at24->macc.read = at24_macc_read; + + writable = !(chip.flags & AT24_FLAG_READONLY); + if (writable) { + if (!use_smbus || use_smbus_write) { + + unsigned write_max = chip.page_size; + + at24->macc.write = at24_macc_write; + + at24->bin.write = at24_bin_write; + at24->bin.attr.mode |= S_IWUSR; + + if (write_max > io_limit) + write_max = io_limit; + if (use_smbus && write_max > I2C_SMBUS_BLOCK_MAX) + write_max = I2C_SMBUS_BLOCK_MAX; + at24->write_max = write_max; + + /* buffer (data + address at the beginning) */ + at24->writebuf = devm_kzalloc(&client->dev, + write_max + 2, GFP_KERNEL); + if (!at24->writebuf) + return -ENOMEM; + } else { + dev_warn(&client->dev, + "cannot write due to controller restrictions."); + } + } + + at24->client[0] = client; + + /* use dummy devices for multiple-address chips */ + for (i = 1; i < num_addresses; i++) { + at24->client[i] = i2c_new_dummy(client->adapter, + client->addr + i); + if (!at24->client[i]) { + dev_err(&client->dev, "address 0x%02x unavailable\n", + client->addr + i); + err = -EADDRINUSE; + goto err_clients; + } + } + + err = sysfs_create_bin_file(&client->dev.kobj, &at24->bin); + if (err) + goto err_clients; + + i2c_set_clientdata(client, at24); + + dev_info(&client->dev, "%zu byte %s EEPROM, %s, %u bytes/write\n", + at24->bin.size, client->name, + writable ? "writable" : "read-only", at24->write_max); + if (use_smbus == I2C_SMBUS_WORD_DATA || + use_smbus == I2C_SMBUS_BYTE_DATA) { + dev_notice(&client->dev, "Falling back to %s reads, " + "performance will suffer\n", use_smbus == + I2C_SMBUS_WORD_DATA ? "word" : "byte"); + } + + /* export data to kernel code */ + if (chip.setup) + chip.setup(&at24->macc, chip.context); + + return 0; + +err_clients: + for (i = 1; i < num_addresses; i++) + if (at24->client[i]) + i2c_unregister_device(at24->client[i]); + + return err; +} + +static int at24_remove(struct i2c_client *client) +{ + struct at24_data *at24; + int i; + + at24 = i2c_get_clientdata(client); + sysfs_remove_bin_file(&client->dev.kobj, &at24->bin); + + for (i = 1; i < at24->num_addresses; i++) + i2c_unregister_device(at24->client[i]); + + return 0; +} + +/*-------------------------------------------------------------------------*/ + +static struct i2c_driver at24_driver = { + .driver = { + .name = "at24", + .owner = THIS_MODULE, + }, + .probe = at24_probe, + .remove = at24_remove, + .id_table = at24_ids, +}; + +static int __init at24_init(void) +{ + if (!io_limit) { + pr_err("at24: io_limit must not be 0!\n"); + return -EINVAL; + } + + io_limit = rounddown_pow_of_two(io_limit); + return i2c_add_driver(&at24_driver); +} +module_init(at24_init); + +static void __exit at24_exit(void) +{ + i2c_del_driver(&at24_driver); +} +module_exit(at24_exit); + +MODULE_DESCRIPTION("Driver for most I2C EEPROMs"); +MODULE_AUTHOR("David Brownell and Wolfram Sang"); +MODULE_LICENSE("GPL"); diff --git a/kernel/drivers/misc/eeprom/at25.c b/kernel/drivers/misc/eeprom/at25.c new file mode 100644 index 000000000..0a1af93ec --- /dev/null +++ b/kernel/drivers/misc/eeprom/at25.c @@ -0,0 +1,477 @@ +/* + * at25.c -- support most SPI EEPROMs, such as Atmel AT25 models + * + * Copyright (C) 2006 David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/sched.h> + +#include <linux/spi/spi.h> +#include <linux/spi/eeprom.h> +#include <linux/property.h> + +/* + * NOTE: this is an *EEPROM* driver. The vagaries of product naming + * mean that some AT25 products are EEPROMs, and others are FLASH. + * Handle FLASH chips with the drivers/mtd/devices/m25p80.c driver, + * not this one! + */ + +struct at25_data { + struct spi_device *spi; + struct memory_accessor mem; + struct mutex lock; + struct spi_eeprom chip; + struct bin_attribute bin; + unsigned addrlen; +}; + +#define AT25_WREN 0x06 /* latch the write enable */ +#define AT25_WRDI 0x04 /* reset the write enable */ +#define AT25_RDSR 0x05 /* read status register */ +#define AT25_WRSR 0x01 /* write status register */ +#define AT25_READ 0x03 /* read byte(s) */ +#define AT25_WRITE 0x02 /* write byte(s)/sector */ + +#define AT25_SR_nRDY 0x01 /* nRDY = write-in-progress */ +#define AT25_SR_WEN 0x02 /* write enable (latched) */ +#define AT25_SR_BP0 0x04 /* BP for software writeprotect */ +#define AT25_SR_BP1 0x08 +#define AT25_SR_WPEN 0x80 /* writeprotect enable */ + +#define AT25_INSTR_BIT3 0x08 /* Additional address bit in instr */ + +#define EE_MAXADDRLEN 3 /* 24 bit addresses, up to 2 MBytes */ + +/* Specs often allow 5 msec for a page write, sometimes 20 msec; + * it's important to recover from write timeouts. + */ +#define EE_TIMEOUT 25 + +/*-------------------------------------------------------------------------*/ + +#define io_limit PAGE_SIZE /* bytes */ + +static ssize_t +at25_ee_read( + struct at25_data *at25, + char *buf, + unsigned offset, + size_t count +) +{ + u8 command[EE_MAXADDRLEN + 1]; + u8 *cp; + ssize_t status; + struct spi_transfer t[2]; + struct spi_message m; + u8 instr; + + if (unlikely(offset >= at25->bin.size)) + return 0; + if ((offset + count) > at25->bin.size) + count = at25->bin.size - offset; + if (unlikely(!count)) + return count; + + cp = command; + + instr = AT25_READ; + if (at25->chip.flags & EE_INSTR_BIT3_IS_ADDR) + if (offset >= (1U << (at25->addrlen * 8))) + instr |= AT25_INSTR_BIT3; + *cp++ = instr; + + /* 8/16/24-bit address is written MSB first */ + switch (at25->addrlen) { + default: /* case 3 */ + *cp++ = offset >> 16; + case 2: + *cp++ = offset >> 8; + case 1: + case 0: /* can't happen: for better codegen */ + *cp++ = offset >> 0; + } + + spi_message_init(&m); + memset(t, 0, sizeof t); + + t[0].tx_buf = command; + t[0].len = at25->addrlen + 1; + spi_message_add_tail(&t[0], &m); + + t[1].rx_buf = buf; + t[1].len = count; + spi_message_add_tail(&t[1], &m); + + mutex_lock(&at25->lock); + + /* Read it all at once. + * + * REVISIT that's potentially a problem with large chips, if + * other devices on the bus need to be accessed regularly or + * this chip is clocked very slowly + */ + status = spi_sync(at25->spi, &m); + dev_dbg(&at25->spi->dev, + "read %Zd bytes at %d --> %d\n", + count, offset, (int) status); + + mutex_unlock(&at25->lock); + return status ? status : count; +} + +static ssize_t +at25_bin_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t count) +{ + struct device *dev; + struct at25_data *at25; + + dev = container_of(kobj, struct device, kobj); + at25 = dev_get_drvdata(dev); + + return at25_ee_read(at25, buf, off, count); +} + + +static ssize_t +at25_ee_write(struct at25_data *at25, const char *buf, loff_t off, + size_t count) +{ + ssize_t status = 0; + unsigned written = 0; + unsigned buf_size; + u8 *bounce; + + if (unlikely(off >= at25->bin.size)) + return -EFBIG; + if ((off + count) > at25->bin.size) + count = at25->bin.size - off; + if (unlikely(!count)) + return count; + + /* Temp buffer starts with command and address */ + buf_size = at25->chip.page_size; + if (buf_size > io_limit) + buf_size = io_limit; + bounce = kmalloc(buf_size + at25->addrlen + 1, GFP_KERNEL); + if (!bounce) + return -ENOMEM; + + /* For write, rollover is within the page ... so we write at + * most one page, then manually roll over to the next page. + */ + mutex_lock(&at25->lock); + do { + unsigned long timeout, retries; + unsigned segment; + unsigned offset = (unsigned) off; + u8 *cp = bounce; + int sr; + u8 instr; + + *cp = AT25_WREN; + status = spi_write(at25->spi, cp, 1); + if (status < 0) { + dev_dbg(&at25->spi->dev, "WREN --> %d\n", + (int) status); + break; + } + + instr = AT25_WRITE; + if (at25->chip.flags & EE_INSTR_BIT3_IS_ADDR) + if (offset >= (1U << (at25->addrlen * 8))) + instr |= AT25_INSTR_BIT3; + *cp++ = instr; + + /* 8/16/24-bit address is written MSB first */ + switch (at25->addrlen) { + default: /* case 3 */ + *cp++ = offset >> 16; + case 2: + *cp++ = offset >> 8; + case 1: + case 0: /* can't happen: for better codegen */ + *cp++ = offset >> 0; + } + + /* Write as much of a page as we can */ + segment = buf_size - (offset % buf_size); + if (segment > count) + segment = count; + memcpy(cp, buf, segment); + status = spi_write(at25->spi, bounce, + segment + at25->addrlen + 1); + dev_dbg(&at25->spi->dev, + "write %u bytes at %u --> %d\n", + segment, offset, (int) status); + if (status < 0) + break; + + /* REVISIT this should detect (or prevent) failed writes + * to readonly sections of the EEPROM... + */ + + /* Wait for non-busy status */ + timeout = jiffies + msecs_to_jiffies(EE_TIMEOUT); + retries = 0; + do { + + sr = spi_w8r8(at25->spi, AT25_RDSR); + if (sr < 0 || (sr & AT25_SR_nRDY)) { + dev_dbg(&at25->spi->dev, + "rdsr --> %d (%02x)\n", sr, sr); + /* at HZ=100, this is sloooow */ + msleep(1); + continue; + } + if (!(sr & AT25_SR_nRDY)) + break; + } while (retries++ < 3 || time_before_eq(jiffies, timeout)); + + if ((sr < 0) || (sr & AT25_SR_nRDY)) { + dev_err(&at25->spi->dev, + "write %d bytes offset %d, " + "timeout after %u msecs\n", + segment, offset, + jiffies_to_msecs(jiffies - + (timeout - EE_TIMEOUT))); + status = -ETIMEDOUT; + break; + } + + off += segment; + buf += segment; + count -= segment; + written += segment; + + } while (count > 0); + + mutex_unlock(&at25->lock); + + kfree(bounce); + return written ? written : status; +} + +static ssize_t +at25_bin_write(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t count) +{ + struct device *dev; + struct at25_data *at25; + + dev = container_of(kobj, struct device, kobj); + at25 = dev_get_drvdata(dev); + + return at25_ee_write(at25, buf, off, count); +} + +/*-------------------------------------------------------------------------*/ + +/* Let in-kernel code access the eeprom data. */ + +static ssize_t at25_mem_read(struct memory_accessor *mem, char *buf, + off_t offset, size_t count) +{ + struct at25_data *at25 = container_of(mem, struct at25_data, mem); + + return at25_ee_read(at25, buf, offset, count); +} + +static ssize_t at25_mem_write(struct memory_accessor *mem, const char *buf, + off_t offset, size_t count) +{ + struct at25_data *at25 = container_of(mem, struct at25_data, mem); + + return at25_ee_write(at25, buf, offset, count); +} + +/*-------------------------------------------------------------------------*/ + +static int at25_fw_to_chip(struct device *dev, struct spi_eeprom *chip) +{ + u32 val; + + memset(chip, 0, sizeof(*chip)); + strncpy(chip->name, "at25", sizeof(chip->name)); + + if (device_property_read_u32(dev, "size", &val) == 0 || + device_property_read_u32(dev, "at25,byte-len", &val) == 0) { + chip->byte_len = val; + } else { + dev_err(dev, "Error: missing \"size\" property\n"); + return -ENODEV; + } + + if (device_property_read_u32(dev, "pagesize", &val) == 0 || + device_property_read_u32(dev, "at25,page-size", &val) == 0) { + chip->page_size = (u16)val; + } else { + dev_err(dev, "Error: missing \"pagesize\" property\n"); + return -ENODEV; + } + + if (device_property_read_u32(dev, "at25,addr-mode", &val) == 0) { + chip->flags = (u16)val; + } else { + if (device_property_read_u32(dev, "address-width", &val)) { + dev_err(dev, + "Error: missing \"address-width\" property\n"); + return -ENODEV; + } + switch (val) { + case 8: + chip->flags |= EE_ADDR1; + break; + case 16: + chip->flags |= EE_ADDR2; + break; + case 24: + chip->flags |= EE_ADDR3; + break; + default: + dev_err(dev, + "Error: bad \"address-width\" property: %u\n", + val); + return -ENODEV; + } + if (device_property_present(dev, "read-only")) + chip->flags |= EE_READONLY; + } + return 0; +} + +static int at25_probe(struct spi_device *spi) +{ + struct at25_data *at25 = NULL; + struct spi_eeprom chip; + int err; + int sr; + int addrlen; + + /* Chip description */ + if (!spi->dev.platform_data) { + err = at25_fw_to_chip(&spi->dev, &chip); + if (err) + return err; + } else + chip = *(struct spi_eeprom *)spi->dev.platform_data; + + /* For now we only support 8/16/24 bit addressing */ + if (chip.flags & EE_ADDR1) + addrlen = 1; + else if (chip.flags & EE_ADDR2) + addrlen = 2; + else if (chip.flags & EE_ADDR3) + addrlen = 3; + else { + dev_dbg(&spi->dev, "unsupported address type\n"); + return -EINVAL; + } + + /* Ping the chip ... the status register is pretty portable, + * unlike probing manufacturer IDs. We do expect that system + * firmware didn't write it in the past few milliseconds! + */ + sr = spi_w8r8(spi, AT25_RDSR); + if (sr < 0 || sr & AT25_SR_nRDY) { + dev_dbg(&spi->dev, "rdsr --> %d (%02x)\n", sr, sr); + return -ENXIO; + } + + at25 = devm_kzalloc(&spi->dev, sizeof(struct at25_data), GFP_KERNEL); + if (!at25) + return -ENOMEM; + + mutex_init(&at25->lock); + at25->chip = chip; + at25->spi = spi_dev_get(spi); + spi_set_drvdata(spi, at25); + at25->addrlen = addrlen; + + /* Export the EEPROM bytes through sysfs, since that's convenient. + * And maybe to other kernel code; it might hold a board's Ethernet + * address, or board-specific calibration data generated on the + * manufacturing floor. + * + * Default to root-only access to the data; EEPROMs often hold data + * that's sensitive for read and/or write, like ethernet addresses, + * security codes, board-specific manufacturing calibrations, etc. + */ + sysfs_bin_attr_init(&at25->bin); + at25->bin.attr.name = "eeprom"; + at25->bin.attr.mode = S_IRUSR; + at25->bin.read = at25_bin_read; + at25->mem.read = at25_mem_read; + + at25->bin.size = at25->chip.byte_len; + if (!(chip.flags & EE_READONLY)) { + at25->bin.write = at25_bin_write; + at25->bin.attr.mode |= S_IWUSR; + at25->mem.write = at25_mem_write; + } + + err = sysfs_create_bin_file(&spi->dev.kobj, &at25->bin); + if (err) + return err; + + if (chip.setup) + chip.setup(&at25->mem, chip.context); + + dev_info(&spi->dev, "%Zd %s %s eeprom%s, pagesize %u\n", + (at25->bin.size < 1024) + ? at25->bin.size + : (at25->bin.size / 1024), + (at25->bin.size < 1024) ? "Byte" : "KByte", + at25->chip.name, + (chip.flags & EE_READONLY) ? " (readonly)" : "", + at25->chip.page_size); + return 0; +} + +static int at25_remove(struct spi_device *spi) +{ + struct at25_data *at25; + + at25 = spi_get_drvdata(spi); + sysfs_remove_bin_file(&spi->dev.kobj, &at25->bin); + return 0; +} + +/*-------------------------------------------------------------------------*/ + +static const struct of_device_id at25_of_match[] = { + { .compatible = "atmel,at25", }, + { } +}; +MODULE_DEVICE_TABLE(of, at25_of_match); + +static struct spi_driver at25_driver = { + .driver = { + .name = "at25", + .owner = THIS_MODULE, + .of_match_table = at25_of_match, + }, + .probe = at25_probe, + .remove = at25_remove, +}; + +module_spi_driver(at25_driver); + +MODULE_DESCRIPTION("Driver for most SPI EEPROMs"); +MODULE_AUTHOR("David Brownell"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("spi:at25"); diff --git a/kernel/drivers/misc/eeprom/digsy_mtc_eeprom.c b/kernel/drivers/misc/eeprom/digsy_mtc_eeprom.c new file mode 100644 index 000000000..66d9e1bae --- /dev/null +++ b/kernel/drivers/misc/eeprom/digsy_mtc_eeprom.c @@ -0,0 +1,85 @@ +/* + * EEPROMs access control driver for display configuration EEPROMs + * on DigsyMTC board. + * + * (C) 2011 DENX Software Engineering, Anatolij Gustschin <agust@denx.de> + * + * 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/gpio.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi_gpio.h> +#include <linux/eeprom_93xx46.h> + +#define GPIO_EEPROM_CLK 216 +#define GPIO_EEPROM_CS 210 +#define GPIO_EEPROM_DI 217 +#define GPIO_EEPROM_DO 249 +#define GPIO_EEPROM_OE 255 +#define EE_SPI_BUS_NUM 1 + +static void digsy_mtc_op_prepare(void *p) +{ + /* enable */ + gpio_set_value(GPIO_EEPROM_OE, 0); +} + +static void digsy_mtc_op_finish(void *p) +{ + /* disable */ + gpio_set_value(GPIO_EEPROM_OE, 1); +} + +struct eeprom_93xx46_platform_data digsy_mtc_eeprom_data = { + .flags = EE_ADDR8, + .prepare = digsy_mtc_op_prepare, + .finish = digsy_mtc_op_finish, +}; + +static struct spi_gpio_platform_data eeprom_spi_gpio_data = { + .sck = GPIO_EEPROM_CLK, + .mosi = GPIO_EEPROM_DI, + .miso = GPIO_EEPROM_DO, + .num_chipselect = 1, +}; + +static struct platform_device digsy_mtc_eeprom = { + .name = "spi_gpio", + .id = EE_SPI_BUS_NUM, + .dev = { + .platform_data = &eeprom_spi_gpio_data, + }, +}; + +static struct spi_board_info digsy_mtc_eeprom_info[] __initdata = { + { + .modalias = "93xx46", + .max_speed_hz = 1000000, + .bus_num = EE_SPI_BUS_NUM, + .chip_select = 0, + .mode = SPI_MODE_0, + .controller_data = (void *)GPIO_EEPROM_CS, + .platform_data = &digsy_mtc_eeprom_data, + }, +}; + +static int __init digsy_mtc_eeprom_devices_init(void) +{ + int ret; + + ret = gpio_request_one(GPIO_EEPROM_OE, GPIOF_OUT_INIT_HIGH, + "93xx46 EEPROMs OE"); + if (ret) { + pr_err("can't request gpio %d\n", GPIO_EEPROM_OE); + return ret; + } + spi_register_board_info(digsy_mtc_eeprom_info, + ARRAY_SIZE(digsy_mtc_eeprom_info)); + return platform_device_register(&digsy_mtc_eeprom); +} +device_initcall(digsy_mtc_eeprom_devices_init); diff --git a/kernel/drivers/misc/eeprom/eeprom.c b/kernel/drivers/misc/eeprom/eeprom.c new file mode 100644 index 000000000..b432873de --- /dev/null +++ b/kernel/drivers/misc/eeprom/eeprom.c @@ -0,0 +1,226 @@ +/* + * Copyright (C) 1998, 1999 Frodo Looijaard <frodol@dds.nl> and + * Philip Edelbrock <phil@netroedge.com> + * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com> + * Copyright (C) 2003 IBM Corp. + * Copyright (C) 2004 Jean Delvare <jdelvare@suse.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/jiffies.h> +#include <linux/i2c.h> +#include <linux/mutex.h> + +/* Addresses to scan */ +static const unsigned short normal_i2c[] = { 0x50, 0x51, 0x52, 0x53, 0x54, + 0x55, 0x56, 0x57, I2C_CLIENT_END }; + + +/* Size of EEPROM in bytes */ +#define EEPROM_SIZE 256 + +/* possible types of eeprom devices */ +enum eeprom_nature { + UNKNOWN, + VAIO, +}; + +/* Each client has this additional data */ +struct eeprom_data { + struct mutex update_lock; + u8 valid; /* bitfield, bit!=0 if slice is valid */ + unsigned long last_updated[8]; /* In jiffies, 8 slices */ + u8 data[EEPROM_SIZE]; /* Register values */ + enum eeprom_nature nature; +}; + + +static void eeprom_update_client(struct i2c_client *client, u8 slice) +{ + struct eeprom_data *data = i2c_get_clientdata(client); + int i; + + mutex_lock(&data->update_lock); + + if (!(data->valid & (1 << slice)) || + time_after(jiffies, data->last_updated[slice] + 300 * HZ)) { + dev_dbg(&client->dev, "Starting eeprom update, slice %u\n", slice); + + if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { + for (i = slice << 5; i < (slice + 1) << 5; i += 32) + if (i2c_smbus_read_i2c_block_data(client, i, + 32, data->data + i) + != 32) + goto exit; + } else { + for (i = slice << 5; i < (slice + 1) << 5; i += 2) { + int word = i2c_smbus_read_word_data(client, i); + if (word < 0) + goto exit; + data->data[i] = word & 0xff; + data->data[i + 1] = word >> 8; + } + } + data->last_updated[slice] = jiffies; + data->valid |= (1 << slice); + } +exit: + mutex_unlock(&data->update_lock); +} + +static ssize_t eeprom_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t count) +{ + struct i2c_client *client = to_i2c_client(container_of(kobj, struct device, kobj)); + struct eeprom_data *data = i2c_get_clientdata(client); + u8 slice; + + if (off > EEPROM_SIZE) + return 0; + if (off + count > EEPROM_SIZE) + count = EEPROM_SIZE - off; + + /* Only refresh slices which contain requested bytes */ + for (slice = off >> 5; slice <= (off + count - 1) >> 5; slice++) + eeprom_update_client(client, slice); + + /* Hide Vaio private settings to regular users: + - BIOS passwords: bytes 0x00 to 0x0f + - UUID: bytes 0x10 to 0x1f + - Serial number: 0xc0 to 0xdf */ + if (data->nature == VAIO && !capable(CAP_SYS_ADMIN)) { + int i; + + for (i = 0; i < count; i++) { + if ((off + i <= 0x1f) || + (off + i >= 0xc0 && off + i <= 0xdf)) + buf[i] = 0; + else + buf[i] = data->data[off + i]; + } + } else { + memcpy(buf, &data->data[off], count); + } + + return count; +} + +static struct bin_attribute eeprom_attr = { + .attr = { + .name = "eeprom", + .mode = S_IRUGO, + }, + .size = EEPROM_SIZE, + .read = eeprom_read, +}; + +/* Return 0 if detection is successful, -ENODEV otherwise */ +static int eeprom_detect(struct i2c_client *client, struct i2c_board_info *info) +{ + struct i2c_adapter *adapter = client->adapter; + + /* EDID EEPROMs are often 24C00 EEPROMs, which answer to all + addresses 0x50-0x57, but we only care about 0x50. So decline + attaching to addresses >= 0x51 on DDC buses */ + if (!(adapter->class & I2C_CLASS_SPD) && client->addr >= 0x51) + return -ENODEV; + + /* There are four ways we can read the EEPROM data: + (1) I2C block reads (faster, but unsupported by most adapters) + (2) Word reads (128% overhead) + (3) Consecutive byte reads (88% overhead, unsafe) + (4) Regular byte data reads (265% overhead) + The third and fourth methods are not implemented by this driver + because all known adapters support one of the first two. */ + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_WORD_DATA) + && !i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) + return -ENODEV; + + strlcpy(info->type, "eeprom", I2C_NAME_SIZE); + + return 0; +} + +static int eeprom_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adapter = client->adapter; + struct eeprom_data *data; + + data = devm_kzalloc(&client->dev, sizeof(struct eeprom_data), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + memset(data->data, 0xff, EEPROM_SIZE); + i2c_set_clientdata(client, data); + mutex_init(&data->update_lock); + data->nature = UNKNOWN; + + /* Detect the Vaio nature of EEPROMs. + We use the "PCG-" or "VGN-" prefix as the signature. */ + if (client->addr == 0x57 + && i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) { + char name[4]; + + name[0] = i2c_smbus_read_byte_data(client, 0x80); + name[1] = i2c_smbus_read_byte_data(client, 0x81); + name[2] = i2c_smbus_read_byte_data(client, 0x82); + name[3] = i2c_smbus_read_byte_data(client, 0x83); + + if (!memcmp(name, "PCG-", 4) || !memcmp(name, "VGN-", 4)) { + dev_info(&client->dev, "Vaio EEPROM detected, " + "enabling privacy protection\n"); + data->nature = VAIO; + } + } + + /* create the sysfs eeprom file */ + return sysfs_create_bin_file(&client->dev.kobj, &eeprom_attr); +} + +static int eeprom_remove(struct i2c_client *client) +{ + sysfs_remove_bin_file(&client->dev.kobj, &eeprom_attr); + + return 0; +} + +static const struct i2c_device_id eeprom_id[] = { + { "eeprom", 0 }, + { } +}; + +static struct i2c_driver eeprom_driver = { + .driver = { + .name = "eeprom", + }, + .probe = eeprom_probe, + .remove = eeprom_remove, + .id_table = eeprom_id, + + .class = I2C_CLASS_DDC | I2C_CLASS_SPD, + .detect = eeprom_detect, + .address_list = normal_i2c, +}; + +module_i2c_driver(eeprom_driver); + +MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and " + "Philip Edelbrock <phil@netroedge.com> and " + "Greg Kroah-Hartman <greg@kroah.com>"); +MODULE_DESCRIPTION("I2C EEPROM driver"); +MODULE_LICENSE("GPL"); diff --git a/kernel/drivers/misc/eeprom/eeprom_93cx6.c b/kernel/drivers/misc/eeprom/eeprom_93cx6.c new file mode 100644 index 000000000..0cf2c9d67 --- /dev/null +++ b/kernel/drivers/misc/eeprom/eeprom_93cx6.c @@ -0,0 +1,381 @@ +/* + * Copyright (C) 2004 - 2006 rt2x00 SourceForge Project + * <http://rt2x00.serialmonkey.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * Module: eeprom_93cx6 + * Abstract: EEPROM reader routines for 93cx6 chipsets. + * Supported chipsets: 93c46 & 93c66. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/eeprom_93cx6.h> + +MODULE_AUTHOR("http://rt2x00.serialmonkey.com"); +MODULE_VERSION("1.0"); +MODULE_DESCRIPTION("EEPROM 93cx6 chip driver"); +MODULE_LICENSE("GPL"); + +static inline void eeprom_93cx6_pulse_high(struct eeprom_93cx6 *eeprom) +{ + eeprom->reg_data_clock = 1; + eeprom->register_write(eeprom); + + /* + * Add a short delay for the pulse to work. + * According to the specifications the "maximum minimum" + * time should be 450ns. + */ + ndelay(450); +} + +static inline void eeprom_93cx6_pulse_low(struct eeprom_93cx6 *eeprom) +{ + eeprom->reg_data_clock = 0; + eeprom->register_write(eeprom); + + /* + * Add a short delay for the pulse to work. + * According to the specifications the "maximum minimum" + * time should be 450ns. + */ + ndelay(450); +} + +static void eeprom_93cx6_startup(struct eeprom_93cx6 *eeprom) +{ + /* + * Clear all flags, and enable chip select. + */ + eeprom->register_read(eeprom); + eeprom->reg_data_in = 0; + eeprom->reg_data_out = 0; + eeprom->reg_data_clock = 0; + eeprom->reg_chip_select = 1; + eeprom->drive_data = 1; + eeprom->register_write(eeprom); + + /* + * kick a pulse. + */ + eeprom_93cx6_pulse_high(eeprom); + eeprom_93cx6_pulse_low(eeprom); +} + +static void eeprom_93cx6_cleanup(struct eeprom_93cx6 *eeprom) +{ + /* + * Clear chip_select and data_in flags. + */ + eeprom->register_read(eeprom); + eeprom->reg_data_in = 0; + eeprom->reg_chip_select = 0; + eeprom->register_write(eeprom); + + /* + * kick a pulse. + */ + eeprom_93cx6_pulse_high(eeprom); + eeprom_93cx6_pulse_low(eeprom); +} + +static void eeprom_93cx6_write_bits(struct eeprom_93cx6 *eeprom, + const u16 data, const u16 count) +{ + unsigned int i; + + eeprom->register_read(eeprom); + + /* + * Clear data flags. + */ + eeprom->reg_data_in = 0; + eeprom->reg_data_out = 0; + eeprom->drive_data = 1; + + /* + * Start writing all bits. + */ + for (i = count; i > 0; i--) { + /* + * Check if this bit needs to be set. + */ + eeprom->reg_data_in = !!(data & (1 << (i - 1))); + + /* + * Write the bit to the eeprom register. + */ + eeprom->register_write(eeprom); + + /* + * Kick a pulse. + */ + eeprom_93cx6_pulse_high(eeprom); + eeprom_93cx6_pulse_low(eeprom); + } + + eeprom->reg_data_in = 0; + eeprom->register_write(eeprom); +} + +static void eeprom_93cx6_read_bits(struct eeprom_93cx6 *eeprom, + u16 *data, const u16 count) +{ + unsigned int i; + u16 buf = 0; + + eeprom->register_read(eeprom); + + /* + * Clear data flags. + */ + eeprom->reg_data_in = 0; + eeprom->reg_data_out = 0; + eeprom->drive_data = 0; + + /* + * Start reading all bits. + */ + for (i = count; i > 0; i--) { + eeprom_93cx6_pulse_high(eeprom); + + eeprom->register_read(eeprom); + + /* + * Clear data_in flag. + */ + eeprom->reg_data_in = 0; + + /* + * Read if the bit has been set. + */ + if (eeprom->reg_data_out) + buf |= (1 << (i - 1)); + + eeprom_93cx6_pulse_low(eeprom); + } + + *data = buf; +} + +/** + * eeprom_93cx6_read - Read a word from eeprom + * @eeprom: Pointer to eeprom structure + * @word: Word index from where we should start reading + * @data: target pointer where the information will have to be stored + * + * This function will read the eeprom data as host-endian word + * into the given data pointer. + */ +void eeprom_93cx6_read(struct eeprom_93cx6 *eeprom, const u8 word, + u16 *data) +{ + u16 command; + + /* + * Initialize the eeprom register + */ + eeprom_93cx6_startup(eeprom); + + /* + * Select the read opcode and the word to be read. + */ + command = (PCI_EEPROM_READ_OPCODE << eeprom->width) | word; + eeprom_93cx6_write_bits(eeprom, command, + PCI_EEPROM_WIDTH_OPCODE + eeprom->width); + + /* + * Read the requested 16 bits. + */ + eeprom_93cx6_read_bits(eeprom, data, 16); + + /* + * Cleanup eeprom register. + */ + eeprom_93cx6_cleanup(eeprom); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_read); + +/** + * eeprom_93cx6_multiread - Read multiple words from eeprom + * @eeprom: Pointer to eeprom structure + * @word: Word index from where we should start reading + * @data: target pointer where the information will have to be stored + * @words: Number of words that should be read. + * + * This function will read all requested words from the eeprom, + * this is done by calling eeprom_93cx6_read() multiple times. + * But with the additional change that while the eeprom_93cx6_read + * will return host ordered bytes, this method will return little + * endian words. + */ +void eeprom_93cx6_multiread(struct eeprom_93cx6 *eeprom, const u8 word, + __le16 *data, const u16 words) +{ + unsigned int i; + u16 tmp; + + for (i = 0; i < words; i++) { + tmp = 0; + eeprom_93cx6_read(eeprom, word + i, &tmp); + data[i] = cpu_to_le16(tmp); + } +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_multiread); + +/** + * eeprom_93cx6_readb - Read a byte from eeprom + * @eeprom: Pointer to eeprom structure + * @word: Byte index from where we should start reading + * @data: target pointer where the information will have to be stored + * + * This function will read a byte of the eeprom data + * into the given data pointer. + */ +void eeprom_93cx6_readb(struct eeprom_93cx6 *eeprom, const u8 byte, + u8 *data) +{ + u16 command; + u16 tmp; + + /* + * Initialize the eeprom register + */ + eeprom_93cx6_startup(eeprom); + + /* + * Select the read opcode and the byte to be read. + */ + command = (PCI_EEPROM_READ_OPCODE << (eeprom->width + 1)) | byte; + eeprom_93cx6_write_bits(eeprom, command, + PCI_EEPROM_WIDTH_OPCODE + eeprom->width + 1); + + /* + * Read the requested 8 bits. + */ + eeprom_93cx6_read_bits(eeprom, &tmp, 8); + *data = tmp & 0xff; + + /* + * Cleanup eeprom register. + */ + eeprom_93cx6_cleanup(eeprom); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_readb); + +/** + * eeprom_93cx6_multireadb - Read multiple bytes from eeprom + * @eeprom: Pointer to eeprom structure + * @byte: Index from where we should start reading + * @data: target pointer where the information will have to be stored + * @words: Number of bytes that should be read. + * + * This function will read all requested bytes from the eeprom, + * this is done by calling eeprom_93cx6_readb() multiple times. + */ +void eeprom_93cx6_multireadb(struct eeprom_93cx6 *eeprom, const u8 byte, + u8 *data, const u16 bytes) +{ + unsigned int i; + + for (i = 0; i < bytes; i++) + eeprom_93cx6_readb(eeprom, byte + i, &data[i]); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_multireadb); + +/** + * eeprom_93cx6_wren - set the write enable state + * @eeprom: Pointer to eeprom structure + * @enable: true to enable writes, otherwise disable writes + * + * Set the EEPROM write enable state to either allow or deny + * writes depending on the @enable value. + */ +void eeprom_93cx6_wren(struct eeprom_93cx6 *eeprom, bool enable) +{ + u16 command; + + /* start the command */ + eeprom_93cx6_startup(eeprom); + + /* create command to enable/disable */ + + command = enable ? PCI_EEPROM_EWEN_OPCODE : PCI_EEPROM_EWDS_OPCODE; + command <<= (eeprom->width - 2); + + eeprom_93cx6_write_bits(eeprom, command, + PCI_EEPROM_WIDTH_OPCODE + eeprom->width); + + eeprom_93cx6_cleanup(eeprom); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_wren); + +/** + * eeprom_93cx6_write - write data to the EEPROM + * @eeprom: Pointer to eeprom structure + * @addr: Address to write data to. + * @data: The data to write to address @addr. + * + * Write the @data to the specified @addr in the EEPROM and + * waiting for the device to finish writing. + * + * Note, since we do not expect large number of write operations + * we delay in between parts of the operation to avoid using excessive + * amounts of CPU time busy waiting. + */ +void eeprom_93cx6_write(struct eeprom_93cx6 *eeprom, u8 addr, u16 data) +{ + int timeout = 100; + u16 command; + + /* start the command */ + eeprom_93cx6_startup(eeprom); + + command = PCI_EEPROM_WRITE_OPCODE << eeprom->width; + command |= addr; + + /* send write command */ + eeprom_93cx6_write_bits(eeprom, command, + PCI_EEPROM_WIDTH_OPCODE + eeprom->width); + + /* send data */ + eeprom_93cx6_write_bits(eeprom, data, 16); + + /* get ready to check for busy */ + eeprom->drive_data = 0; + eeprom->reg_chip_select = 1; + eeprom->register_write(eeprom); + + /* wait at-least 250ns to get DO to be the busy signal */ + usleep_range(1000, 2000); + + /* wait for DO to go high to signify finish */ + + while (true) { + eeprom->register_read(eeprom); + + if (eeprom->reg_data_out) + break; + + usleep_range(1000, 2000); + + if (--timeout <= 0) { + printk(KERN_ERR "%s: timeout\n", __func__); + break; + } + } + + eeprom_93cx6_cleanup(eeprom); +} +EXPORT_SYMBOL_GPL(eeprom_93cx6_write); diff --git a/kernel/drivers/misc/eeprom/eeprom_93xx46.c b/kernel/drivers/misc/eeprom/eeprom_93xx46.c new file mode 100644 index 000000000..9ebeacdb8 --- /dev/null +++ b/kernel/drivers/misc/eeprom/eeprom_93xx46.c @@ -0,0 +1,398 @@ +/* + * Driver for 93xx46 EEPROMs + * + * (C) 2011 DENX Software Engineering, Anatolij Gustschin <agust@denx.de> + * + * 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/delay.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <linux/spi/spi.h> +#include <linux/sysfs.h> +#include <linux/eeprom_93xx46.h> + +#define OP_START 0x4 +#define OP_WRITE (OP_START | 0x1) +#define OP_READ (OP_START | 0x2) +#define ADDR_EWDS 0x00 +#define ADDR_ERAL 0x20 +#define ADDR_EWEN 0x30 + +struct eeprom_93xx46_dev { + struct spi_device *spi; + struct eeprom_93xx46_platform_data *pdata; + struct bin_attribute bin; + struct mutex lock; + int addrlen; +}; + +static ssize_t +eeprom_93xx46_bin_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t count) +{ + struct eeprom_93xx46_dev *edev; + struct device *dev; + struct spi_message m; + struct spi_transfer t[2]; + int bits, ret; + u16 cmd_addr; + + dev = container_of(kobj, struct device, kobj); + edev = dev_get_drvdata(dev); + + if (unlikely(off >= edev->bin.size)) + return 0; + if ((off + count) > edev->bin.size) + count = edev->bin.size - off; + if (unlikely(!count)) + return count; + + cmd_addr = OP_READ << edev->addrlen; + + if (edev->addrlen == 7) { + cmd_addr |= off & 0x7f; + bits = 10; + } else { + cmd_addr |= off & 0x3f; + bits = 9; + } + + dev_dbg(&edev->spi->dev, "read cmd 0x%x, %d Hz\n", + cmd_addr, edev->spi->max_speed_hz); + + spi_message_init(&m); + memset(t, 0, sizeof(t)); + + t[0].tx_buf = (char *)&cmd_addr; + t[0].len = 2; + t[0].bits_per_word = bits; + spi_message_add_tail(&t[0], &m); + + t[1].rx_buf = buf; + t[1].len = count; + t[1].bits_per_word = 8; + spi_message_add_tail(&t[1], &m); + + mutex_lock(&edev->lock); + + if (edev->pdata->prepare) + edev->pdata->prepare(edev); + + ret = spi_sync(edev->spi, &m); + /* have to wait at least Tcsl ns */ + ndelay(250); + if (ret) { + dev_err(&edev->spi->dev, "read %zu bytes at %d: err. %d\n", + count, (int)off, ret); + } + + if (edev->pdata->finish) + edev->pdata->finish(edev); + + mutex_unlock(&edev->lock); + return ret ? : count; +} + +static int eeprom_93xx46_ew(struct eeprom_93xx46_dev *edev, int is_on) +{ + struct spi_message m; + struct spi_transfer t; + int bits, ret; + u16 cmd_addr; + + cmd_addr = OP_START << edev->addrlen; + if (edev->addrlen == 7) { + cmd_addr |= (is_on ? ADDR_EWEN : ADDR_EWDS) << 1; + bits = 10; + } else { + cmd_addr |= (is_on ? ADDR_EWEN : ADDR_EWDS); + bits = 9; + } + + dev_dbg(&edev->spi->dev, "ew cmd 0x%04x\n", cmd_addr); + + spi_message_init(&m); + memset(&t, 0, sizeof(t)); + + t.tx_buf = &cmd_addr; + t.len = 2; + t.bits_per_word = bits; + spi_message_add_tail(&t, &m); + + mutex_lock(&edev->lock); + + if (edev->pdata->prepare) + edev->pdata->prepare(edev); + + ret = spi_sync(edev->spi, &m); + /* have to wait at least Tcsl ns */ + ndelay(250); + if (ret) + dev_err(&edev->spi->dev, "erase/write %sable error %d\n", + is_on ? "en" : "dis", ret); + + if (edev->pdata->finish) + edev->pdata->finish(edev); + + mutex_unlock(&edev->lock); + return ret; +} + +static ssize_t +eeprom_93xx46_write_word(struct eeprom_93xx46_dev *edev, + const char *buf, unsigned off) +{ + struct spi_message m; + struct spi_transfer t[2]; + int bits, data_len, ret; + u16 cmd_addr; + + cmd_addr = OP_WRITE << edev->addrlen; + + if (edev->addrlen == 7) { + cmd_addr |= off & 0x7f; + bits = 10; + data_len = 1; + } else { + cmd_addr |= off & 0x3f; + bits = 9; + data_len = 2; + } + + dev_dbg(&edev->spi->dev, "write cmd 0x%x\n", cmd_addr); + + spi_message_init(&m); + memset(t, 0, sizeof(t)); + + t[0].tx_buf = (char *)&cmd_addr; + t[0].len = 2; + t[0].bits_per_word = bits; + spi_message_add_tail(&t[0], &m); + + t[1].tx_buf = buf; + t[1].len = data_len; + t[1].bits_per_word = 8; + spi_message_add_tail(&t[1], &m); + + ret = spi_sync(edev->spi, &m); + /* have to wait program cycle time Twc ms */ + mdelay(6); + return ret; +} + +static ssize_t +eeprom_93xx46_bin_write(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t count) +{ + struct eeprom_93xx46_dev *edev; + struct device *dev; + int i, ret, step = 1; + + dev = container_of(kobj, struct device, kobj); + edev = dev_get_drvdata(dev); + + if (unlikely(off >= edev->bin.size)) + return -EFBIG; + if ((off + count) > edev->bin.size) + count = edev->bin.size - off; + if (unlikely(!count)) + return count; + + /* only write even number of bytes on 16-bit devices */ + if (edev->addrlen == 6) { + step = 2; + count &= ~1; + } + + /* erase/write enable */ + ret = eeprom_93xx46_ew(edev, 1); + if (ret) + return ret; + + mutex_lock(&edev->lock); + + if (edev->pdata->prepare) + edev->pdata->prepare(edev); + + for (i = 0; i < count; i += step) { + ret = eeprom_93xx46_write_word(edev, &buf[i], off + i); + if (ret) { + dev_err(&edev->spi->dev, "write failed at %d: %d\n", + (int)off + i, ret); + break; + } + } + + if (edev->pdata->finish) + edev->pdata->finish(edev); + + mutex_unlock(&edev->lock); + + /* erase/write disable */ + eeprom_93xx46_ew(edev, 0); + return ret ? : count; +} + +static int eeprom_93xx46_eral(struct eeprom_93xx46_dev *edev) +{ + struct eeprom_93xx46_platform_data *pd = edev->pdata; + struct spi_message m; + struct spi_transfer t; + int bits, ret; + u16 cmd_addr; + + cmd_addr = OP_START << edev->addrlen; + if (edev->addrlen == 7) { + cmd_addr |= ADDR_ERAL << 1; + bits = 10; + } else { + cmd_addr |= ADDR_ERAL; + bits = 9; + } + + spi_message_init(&m); + memset(&t, 0, sizeof(t)); + + t.tx_buf = &cmd_addr; + t.len = 2; + t.bits_per_word = bits; + spi_message_add_tail(&t, &m); + + mutex_lock(&edev->lock); + + if (edev->pdata->prepare) + edev->pdata->prepare(edev); + + ret = spi_sync(edev->spi, &m); + if (ret) + dev_err(&edev->spi->dev, "erase error %d\n", ret); + /* have to wait erase cycle time Tec ms */ + mdelay(6); + + if (pd->finish) + pd->finish(edev); + + mutex_unlock(&edev->lock); + return ret; +} + +static ssize_t eeprom_93xx46_store_erase(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct eeprom_93xx46_dev *edev = dev_get_drvdata(dev); + int erase = 0, ret; + + sscanf(buf, "%d", &erase); + if (erase) { + ret = eeprom_93xx46_ew(edev, 1); + if (ret) + return ret; + ret = eeprom_93xx46_eral(edev); + if (ret) + return ret; + ret = eeprom_93xx46_ew(edev, 0); + if (ret) + return ret; + } + return count; +} +static DEVICE_ATTR(erase, S_IWUSR, NULL, eeprom_93xx46_store_erase); + +static int eeprom_93xx46_probe(struct spi_device *spi) +{ + struct eeprom_93xx46_platform_data *pd; + struct eeprom_93xx46_dev *edev; + int err; + + pd = spi->dev.platform_data; + if (!pd) { + dev_err(&spi->dev, "missing platform data\n"); + return -ENODEV; + } + + edev = kzalloc(sizeof(*edev), GFP_KERNEL); + if (!edev) + return -ENOMEM; + + if (pd->flags & EE_ADDR8) + edev->addrlen = 7; + else if (pd->flags & EE_ADDR16) + edev->addrlen = 6; + else { + dev_err(&spi->dev, "unspecified address type\n"); + err = -EINVAL; + goto fail; + } + + mutex_init(&edev->lock); + + edev->spi = spi_dev_get(spi); + edev->pdata = pd; + + sysfs_bin_attr_init(&edev->bin); + edev->bin.attr.name = "eeprom"; + edev->bin.attr.mode = S_IRUSR; + edev->bin.read = eeprom_93xx46_bin_read; + edev->bin.size = 128; + if (!(pd->flags & EE_READONLY)) { + edev->bin.write = eeprom_93xx46_bin_write; + edev->bin.attr.mode |= S_IWUSR; + } + + err = sysfs_create_bin_file(&spi->dev.kobj, &edev->bin); + if (err) + goto fail; + + dev_info(&spi->dev, "%d-bit eeprom %s\n", + (pd->flags & EE_ADDR8) ? 8 : 16, + (pd->flags & EE_READONLY) ? "(readonly)" : ""); + + if (!(pd->flags & EE_READONLY)) { + if (device_create_file(&spi->dev, &dev_attr_erase)) + dev_err(&spi->dev, "can't create erase interface\n"); + } + + spi_set_drvdata(spi, edev); + return 0; +fail: + kfree(edev); + return err; +} + +static int eeprom_93xx46_remove(struct spi_device *spi) +{ + struct eeprom_93xx46_dev *edev = spi_get_drvdata(spi); + + if (!(edev->pdata->flags & EE_READONLY)) + device_remove_file(&spi->dev, &dev_attr_erase); + + sysfs_remove_bin_file(&spi->dev.kobj, &edev->bin); + kfree(edev); + return 0; +} + +static struct spi_driver eeprom_93xx46_driver = { + .driver = { + .name = "93xx46", + .owner = THIS_MODULE, + }, + .probe = eeprom_93xx46_probe, + .remove = eeprom_93xx46_remove, +}; + +module_spi_driver(eeprom_93xx46_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Driver for 93xx46 EEPROMs"); +MODULE_AUTHOR("Anatolij Gustschin <agust@denx.de>"); +MODULE_ALIAS("spi:93xx46"); diff --git a/kernel/drivers/misc/eeprom/max6875.c b/kernel/drivers/misc/eeprom/max6875.c new file mode 100644 index 000000000..580ff9df5 --- /dev/null +++ b/kernel/drivers/misc/eeprom/max6875.c @@ -0,0 +1,214 @@ +/* + * max6875.c - driver for MAX6874/MAX6875 + * + * Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com> + * + * Based on eeprom.c + * + * The MAX6875 has a bank of registers and two banks of EEPROM. + * Address ranges are defined as follows: + * * 0x0000 - 0x0046 = configuration registers + * * 0x8000 - 0x8046 = configuration EEPROM + * * 0x8100 - 0x82FF = user EEPROM + * + * This driver makes the user EEPROM available for read. + * + * The registers & config EEPROM should be accessed via i2c-dev. + * + * The MAX6875 ignores the lowest address bit, so each chip responds to + * two addresses - 0x50/0x51 and 0x52/0x53. + * + * Note that the MAX6875 uses i2c_smbus_write_byte_data() to set the read + * address, so this driver is destructive if loaded for the wrong EEPROM chip. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/mutex.h> + +/* The MAX6875 can only read/write 16 bytes at a time */ +#define SLICE_SIZE 16 +#define SLICE_BITS 4 + +/* USER EEPROM is at addresses 0x8100 - 0x82FF */ +#define USER_EEPROM_BASE 0x8100 +#define USER_EEPROM_SIZE 0x0200 +#define USER_EEPROM_SLICES 32 + +/* MAX6875 commands */ +#define MAX6875_CMD_BLK_READ 0x84 + +/* Each client has this additional data */ +struct max6875_data { + struct i2c_client *fake_client; + struct mutex update_lock; + + u32 valid; + u8 data[USER_EEPROM_SIZE]; + unsigned long last_updated[USER_EEPROM_SLICES]; +}; + +static void max6875_update_slice(struct i2c_client *client, int slice) +{ + struct max6875_data *data = i2c_get_clientdata(client); + int i, j, addr; + u8 *buf; + + if (slice >= USER_EEPROM_SLICES) + return; + + mutex_lock(&data->update_lock); + + buf = &data->data[slice << SLICE_BITS]; + + if (!(data->valid & (1 << slice)) || + time_after(jiffies, data->last_updated[slice])) { + + dev_dbg(&client->dev, "Starting update of slice %u\n", slice); + + data->valid &= ~(1 << slice); + + addr = USER_EEPROM_BASE + (slice << SLICE_BITS); + + /* select the eeprom address */ + if (i2c_smbus_write_byte_data(client, addr >> 8, addr & 0xFF)) { + dev_err(&client->dev, "address set failed\n"); + goto exit_up; + } + + if (i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { + if (i2c_smbus_read_i2c_block_data(client, + MAX6875_CMD_BLK_READ, + SLICE_SIZE, + buf) != SLICE_SIZE) { + goto exit_up; + } + } else { + for (i = 0; i < SLICE_SIZE; i++) { + j = i2c_smbus_read_byte(client); + if (j < 0) { + goto exit_up; + } + buf[i] = j; + } + } + data->last_updated[slice] = jiffies; + data->valid |= (1 << slice); + } +exit_up: + mutex_unlock(&data->update_lock); +} + +static ssize_t max6875_read(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t count) +{ + struct i2c_client *client = kobj_to_i2c_client(kobj); + struct max6875_data *data = i2c_get_clientdata(client); + int slice, max_slice; + + if (off > USER_EEPROM_SIZE) + return 0; + + if (off + count > USER_EEPROM_SIZE) + count = USER_EEPROM_SIZE - off; + + /* refresh slices which contain requested bytes */ + max_slice = (off + count - 1) >> SLICE_BITS; + for (slice = (off >> SLICE_BITS); slice <= max_slice; slice++) + max6875_update_slice(client, slice); + + memcpy(buf, &data->data[off], count); + + return count; +} + +static struct bin_attribute user_eeprom_attr = { + .attr = { + .name = "eeprom", + .mode = S_IRUGO, + }, + .size = USER_EEPROM_SIZE, + .read = max6875_read, +}; + +static int max6875_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct i2c_adapter *adapter = client->adapter; + struct max6875_data *data; + int err; + + if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_WRITE_BYTE_DATA + | I2C_FUNC_SMBUS_READ_BYTE)) + return -ENODEV; + + /* Only bind to even addresses */ + if (client->addr & 1) + return -ENODEV; + + if (!(data = kzalloc(sizeof(struct max6875_data), GFP_KERNEL))) + return -ENOMEM; + + /* A fake client is created on the odd address */ + data->fake_client = i2c_new_dummy(client->adapter, client->addr + 1); + if (!data->fake_client) { + err = -ENOMEM; + goto exit_kfree; + } + + /* Init real i2c_client */ + i2c_set_clientdata(client, data); + mutex_init(&data->update_lock); + + err = sysfs_create_bin_file(&client->dev.kobj, &user_eeprom_attr); + if (err) + goto exit_remove_fake; + + return 0; + +exit_remove_fake: + i2c_unregister_device(data->fake_client); +exit_kfree: + kfree(data); + return err; +} + +static int max6875_remove(struct i2c_client *client) +{ + struct max6875_data *data = i2c_get_clientdata(client); + + i2c_unregister_device(data->fake_client); + + sysfs_remove_bin_file(&client->dev.kobj, &user_eeprom_attr); + kfree(data); + + return 0; +} + +static const struct i2c_device_id max6875_id[] = { + { "max6875", 0 }, + { } +}; + +static struct i2c_driver max6875_driver = { + .driver = { + .name = "max6875", + }, + .probe = max6875_probe, + .remove = max6875_remove, + .id_table = max6875_id, +}; + +module_i2c_driver(max6875_driver); + +MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>"); +MODULE_DESCRIPTION("MAX6875 driver"); +MODULE_LICENSE("GPL"); diff --git a/kernel/drivers/misc/eeprom/sunxi_sid.c b/kernel/drivers/misc/eeprom/sunxi_sid.c new file mode 100644 index 000000000..8385177ff --- /dev/null +++ b/kernel/drivers/misc/eeprom/sunxi_sid.c @@ -0,0 +1,156 @@ +/* + * Copyright (c) 2013 Oliver Schinagl <oliver@schinagl.nl> + * http://www.linux-sunxi.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * This driver exposes the Allwinner security ID, efuses exported in byte- + * sized chunks. + */ + +#include <linux/compiler.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/export.h> +#include <linux/fs.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/kobject.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/random.h> +#include <linux/slab.h> +#include <linux/stat.h> +#include <linux/sysfs.h> +#include <linux/types.h> + +#define DRV_NAME "sunxi-sid" + +struct sunxi_sid_data { + void __iomem *reg_base; + unsigned int keysize; +}; + +/* We read the entire key, due to a 32 bit read alignment requirement. Since we + * want to return the requested byte, this results in somewhat slower code and + * uses 4 times more reads as needed but keeps code simpler. Since the SID is + * only very rarely probed, this is not really an issue. + */ +static u8 sunxi_sid_read_byte(const struct sunxi_sid_data *sid_data, + const unsigned int offset) +{ + u32 sid_key; + + if (offset >= sid_data->keysize) + return 0; + + sid_key = ioread32be(sid_data->reg_base + round_down(offset, 4)); + sid_key >>= (offset % 4) * 8; + + return sid_key; /* Only return the last byte */ +} + +static ssize_t sid_read(struct file *fd, struct kobject *kobj, + struct bin_attribute *attr, char *buf, + loff_t pos, size_t size) +{ + struct platform_device *pdev; + struct sunxi_sid_data *sid_data; + int i; + + pdev = to_platform_device(kobj_to_dev(kobj)); + sid_data = platform_get_drvdata(pdev); + + if (pos < 0 || pos >= sid_data->keysize) + return 0; + if (size > sid_data->keysize - pos) + size = sid_data->keysize - pos; + + for (i = 0; i < size; i++) + buf[i] = sunxi_sid_read_byte(sid_data, pos + i); + + return i; +} + +static struct bin_attribute sid_bin_attr = { + .attr = { .name = "eeprom", .mode = S_IRUGO, }, + .read = sid_read, +}; + +static int sunxi_sid_remove(struct platform_device *pdev) +{ + device_remove_bin_file(&pdev->dev, &sid_bin_attr); + dev_dbg(&pdev->dev, "driver unloaded\n"); + + return 0; +} + +static const struct of_device_id sunxi_sid_of_match[] = { + { .compatible = "allwinner,sun4i-a10-sid", .data = (void *)16}, + { .compatible = "allwinner,sun7i-a20-sid", .data = (void *)512}, + {/* sentinel */}, +}; +MODULE_DEVICE_TABLE(of, sunxi_sid_of_match); + +static int sunxi_sid_probe(struct platform_device *pdev) +{ + struct sunxi_sid_data *sid_data; + struct resource *res; + const struct of_device_id *of_dev_id; + u8 *entropy; + unsigned int i; + + sid_data = devm_kzalloc(&pdev->dev, sizeof(struct sunxi_sid_data), + GFP_KERNEL); + if (!sid_data) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + sid_data->reg_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(sid_data->reg_base)) + return PTR_ERR(sid_data->reg_base); + + of_dev_id = of_match_device(sunxi_sid_of_match, &pdev->dev); + if (!of_dev_id) + return -ENODEV; + sid_data->keysize = (int)of_dev_id->data; + + platform_set_drvdata(pdev, sid_data); + + sid_bin_attr.size = sid_data->keysize; + if (device_create_bin_file(&pdev->dev, &sid_bin_attr)) + return -ENODEV; + + entropy = kzalloc(sizeof(u8) * sid_data->keysize, GFP_KERNEL); + for (i = 0; i < sid_data->keysize; i++) + entropy[i] = sunxi_sid_read_byte(sid_data, i); + add_device_randomness(entropy, sid_data->keysize); + kfree(entropy); + + dev_dbg(&pdev->dev, "loaded\n"); + + return 0; +} + +static struct platform_driver sunxi_sid_driver = { + .probe = sunxi_sid_probe, + .remove = sunxi_sid_remove, + .driver = { + .name = DRV_NAME, + .of_match_table = sunxi_sid_of_match, + }, +}; +module_platform_driver(sunxi_sid_driver); + +MODULE_AUTHOR("Oliver Schinagl <oliver@schinagl.nl>"); +MODULE_DESCRIPTION("Allwinner sunxi security id driver"); +MODULE_LICENSE("GPL"); |