diff options
| -rw-r--r-- | drivers/w1/slaves/Kconfig | 8 | ||||
| -rw-r--r-- | drivers/w1/slaves/Makefile | 1 | ||||
| -rw-r--r-- | drivers/w1/slaves/w1_ds2805.c | 313 | ||||
| -rw-r--r-- | drivers/w1/w1.c | 2 |
4 files changed, 324 insertions, 0 deletions
diff --git a/drivers/w1/slaves/Kconfig b/drivers/w1/slaves/Kconfig index fb68465908f2..bb4d7ed2ce55 100644 --- a/drivers/w1/slaves/Kconfig +++ b/drivers/w1/slaves/Kconfig @@ -65,6 +65,14 @@ config W1_SLAVE_DS2423 Say Y here if you want to use a 1-wire counter family device (DS2423). +config W1_SLAVE_DS2805 + tristate "112-byte EEPROM support (DS28E05)" + help + Say Y here if you want to use a 1-wire + is a 112-byte user-programmable EEPROM is + organized as 7 pages of 16 bytes each with 64bit + unique number. Requires OverDrive Speed to talk to. + config W1_SLAVE_DS2431 tristate "1kb EEPROM family support (DS2431)" help diff --git a/drivers/w1/slaves/Makefile b/drivers/w1/slaves/Makefile index 54c63e420302..4622d8fed362 100644 --- a/drivers/w1/slaves/Makefile +++ b/drivers/w1/slaves/Makefile @@ -10,6 +10,7 @@ obj-$(CONFIG_W1_SLAVE_DS2413) += w1_ds2413.o obj-$(CONFIG_W1_SLAVE_DS2406) += w1_ds2406.o obj-$(CONFIG_W1_SLAVE_DS2423) += w1_ds2423.o obj-$(CONFIG_W1_SLAVE_DS2431) += w1_ds2431.o +obj-$(CONFIG_W1_SLAVE_DS2805) += w1_ds2805.o obj-$(CONFIG_W1_SLAVE_DS2433) += w1_ds2433.o obj-$(CONFIG_W1_SLAVE_DS2438) += w1_ds2438.o obj-$(CONFIG_W1_SLAVE_DS2760) += w1_ds2760.o diff --git a/drivers/w1/slaves/w1_ds2805.c b/drivers/w1/slaves/w1_ds2805.c new file mode 100644 index 000000000000..29348d283a65 --- /dev/null +++ b/drivers/w1/slaves/w1_ds2805.c @@ -0,0 +1,313 @@ +/* + * w1_ds2805 - w1 family 0d (DS28E05) driver + * + * Copyright (c) 2016 Andrew Worsley amworsley@gmail.com + * + * This source code is licensed under the GNU General Public License, + * Version 2. See the file COPYING for more details. + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/device.h> +#include <linux/types.h> +#include <linux/delay.h> + +#include <linux/w1.h> + +#define W1_EEPROM_DS2805 0x0D + +#define W1_F0D_EEPROM_SIZE 128 +#define W1_F0D_PAGE_BITS 3 +#define W1_F0D_PAGE_SIZE (1<<W1_F0D_PAGE_BITS) +#define W1_F0D_PAGE_MASK 0x0F + +#define W1_F0D_SCRATCH_BITS 1 +#define W1_F0D_SCRATCH_SIZE (1<<W1_F0D_SCRATCH_BITS) +#define W1_F0D_SCRATCH_MASK (W1_F0D_SCRATCH_SIZE-1) + +#define W1_F0D_READ_EEPROM 0xF0 +#define W1_F0D_WRITE_EEPROM 0x55 +#define W1_F0D_RELEASE 0xFF + +#define W1_F0D_CS_OK 0xAA /* Chip Status Ok */ + +#define W1_F0D_TPROG_MS 16 + +#define W1_F0D_READ_RETRIES 10 +#define W1_F0D_READ_MAXLEN W1_F0D_EEPROM_SIZE + +/* + * Check the file size bounds and adjusts count as needed. + * This would not be needed if the file size didn't reset to 0 after a write. + */ +static inline size_t w1_f0d_fix_count(loff_t off, size_t count, size_t size) +{ + if (off > size) + return 0; + + if ((off + count) > size) + return size - off; + + return count; +} + +/* + * Read a block from W1 ROM two times and compares the results. + * If they are equal they are returned, otherwise the read + * is repeated W1_F0D_READ_RETRIES times. + * + * count must not exceed W1_F0D_READ_MAXLEN. + */ +static int w1_f0d_readblock(struct w1_slave *sl, int off, int count, char *buf) +{ + u8 wrbuf[3]; + u8 cmp[W1_F0D_READ_MAXLEN]; + int tries = W1_F0D_READ_RETRIES; + + do { + wrbuf[0] = W1_F0D_READ_EEPROM; + wrbuf[1] = off & 0x7f; + wrbuf[2] = 0; + + if (w1_reset_select_slave(sl)) + return -1; + + w1_write_block(sl->master, wrbuf, sizeof(wrbuf)); + w1_read_block(sl->master, buf, count); + + if (w1_reset_select_slave(sl)) + return -1; + + w1_write_block(sl->master, wrbuf, sizeof(wrbuf)); + w1_read_block(sl->master, cmp, count); + + if (!memcmp(cmp, buf, count)) + return 0; + } while (--tries); + + dev_err(&sl->dev, "proof reading failed %d times\n", + W1_F0D_READ_RETRIES); + + return -1; +} + +static ssize_t w1_f0d_read_bin(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t count) +{ + struct w1_slave *sl = kobj_to_w1_slave(kobj); + int todo = count; + + count = w1_f0d_fix_count(off, count, W1_F0D_EEPROM_SIZE); + if (count == 0) + return 0; + + mutex_lock(&sl->master->mutex); + + /* read directly from the EEPROM in chunks of W1_F0D_READ_MAXLEN */ + while (todo > 0) { + int block_read; + + if (todo >= W1_F0D_READ_MAXLEN) + block_read = W1_F0D_READ_MAXLEN; + else + block_read = todo; + + if (w1_f0d_readblock(sl, off, block_read, buf) < 0) { + count = -EIO; + break; + } + + todo -= W1_F0D_READ_MAXLEN; + buf += W1_F0D_READ_MAXLEN; + off += W1_F0D_READ_MAXLEN; + } + + mutex_unlock(&sl->master->mutex); + + return count; +} + +/* + * Writes to the scratchpad and reads it back for verification. + * Then copies the scratchpad to EEPROM. + * The data must be aligned at W1_F0D_SCRATCH_SIZE bytes and + * must be W1_F0D_SCRATCH_SIZE bytes long. + * The master must be locked. + * + * @param sl The slave structure + * @param addr Address for the write + * @param len length must be <= (W1_F0D_PAGE_SIZE - (addr & W1_F0D_PAGE_MASK)) + * @param data The data to write + * @return 0=Success -1=failure + */ +static int w1_f0d_write(struct w1_slave *sl, int addr, int len, const u8 *data) +{ + int tries = W1_F0D_READ_RETRIES; + u8 wrbuf[3]; + u8 rdbuf[W1_F0D_SCRATCH_SIZE]; + u8 cs; + + if ((addr & 1) || (len != 2)) { + dev_err(&sl->dev, "%s: bad addr/len - addr=%#x len=%d\n", + __func__, addr, len); + return -1; + } + +retry: + + /* Write the data to the scratchpad */ + if (w1_reset_select_slave(sl)) + return -1; + + wrbuf[0] = W1_F0D_WRITE_EEPROM; + wrbuf[1] = addr & 0xff; + wrbuf[2] = 0xff; /* ?? from Example */ + + w1_write_block(sl->master, wrbuf, sizeof(wrbuf)); + w1_write_block(sl->master, data, len); + + w1_read_block(sl->master, rdbuf, sizeof(rdbuf)); + /* Compare what was read against the data written */ + if ((rdbuf[0] != data[0]) || (rdbuf[1] != data[1])) { + + if (--tries) + goto retry; + + dev_err(&sl->dev, + "could not write to eeprom, scratchpad compare failed %d times\n", + W1_F0D_READ_RETRIES); + pr_info("%s: rdbuf = %#x %#x data = %#x %#x\n", + __func__, rdbuf[0], rdbuf[1], data[0], data[1]); + + return -1; + } + + /* Trigger write out to EEPROM */ + w1_write_8(sl->master, W1_F0D_RELEASE); + + /* Sleep for tprog ms to wait for the write to complete */ + msleep(W1_F0D_TPROG_MS); + + /* Check CS (Command Status) == 0xAA ? */ + cs = w1_read_8(sl->master); + if (cs != W1_F0D_CS_OK) { + dev_err(&sl->dev, "save to eeprom failed = CS=%#x\n", cs); + return -1; + } + + return 0; +} + +static ssize_t w1_f0d_write_bin(struct file *filp, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t count) +{ + struct w1_slave *sl = kobj_to_w1_slave(kobj); + int addr, len; + int copy; + + count = w1_f0d_fix_count(off, count, W1_F0D_EEPROM_SIZE); + if (count == 0) + return 0; + + mutex_lock(&sl->master->mutex); + + /* Can only write data in blocks of the size of the scratchpad */ + addr = off; + len = count; + while (len > 0) { + + /* if len too short or addr not aligned */ + if (len < W1_F0D_SCRATCH_SIZE || addr & W1_F0D_SCRATCH_MASK) { + char tmp[W1_F0D_SCRATCH_SIZE]; + + /* read the block and update the parts to be written */ + if (w1_f0d_readblock(sl, addr & ~W1_F0D_SCRATCH_MASK, + W1_F0D_SCRATCH_SIZE, tmp)) { + count = -EIO; + goto out_up; + } + + /* copy at most to the boundary of the PAGE or len */ + copy = W1_F0D_SCRATCH_SIZE - + (addr & W1_F0D_SCRATCH_MASK); + + if (copy > len) + copy = len; + + memcpy(&tmp[addr & W1_F0D_SCRATCH_MASK], buf, copy); + if (w1_f0d_write(sl, addr & ~W1_F0D_SCRATCH_MASK, + W1_F0D_SCRATCH_SIZE, tmp) < 0) { + count = -EIO; + goto out_up; + } + } else { + + copy = W1_F0D_SCRATCH_SIZE; + if (w1_f0d_write(sl, addr, copy, buf) < 0) { + count = -EIO; + goto out_up; + } + } + buf += copy; + addr += copy; + len -= copy; + } + +out_up: + mutex_unlock(&sl->master->mutex); + + return count; +} + +static struct bin_attribute w1_f0d_bin_attr = { + .attr = { + .name = "eeprom", + .mode = S_IRUGO | S_IWUSR, + }, + .size = W1_F0D_EEPROM_SIZE, + .read = w1_f0d_read_bin, + .write = w1_f0d_write_bin, +}; + +static int w1_f0d_add_slave(struct w1_slave *sl) +{ + return sysfs_create_bin_file(&sl->dev.kobj, &w1_f0d_bin_attr); +} + +static void w1_f0d_remove_slave(struct w1_slave *sl) +{ + sysfs_remove_bin_file(&sl->dev.kobj, &w1_f0d_bin_attr); +} + +static struct w1_family_ops w1_f0d_fops = { + .add_slave = w1_f0d_add_slave, + .remove_slave = w1_f0d_remove_slave, +}; + +static struct w1_family w1_family_2d = { + .fid = W1_EEPROM_DS2805, + .fops = &w1_f0d_fops, +}; + +static int __init w1_f0d_init(void) +{ + pr_info("%s()\n", __func__); + return w1_register_family(&w1_family_2d); +} + +static void __exit w1_f0d_fini(void) +{ + pr_info("%s()\n", __func__); + w1_unregister_family(&w1_family_2d); +} + +module_init(w1_f0d_init); +module_exit(w1_f0d_fini); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Andrew Worsley amworsley@gmail.com"); +MODULE_DESCRIPTION("w1 family 0d driver for DS2805, 1kb EEPROM"); diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c index 0f614dfcb09f..3c76e1ca4b83 100644 --- a/drivers/w1/w1.c +++ b/drivers/w1/w1.c @@ -729,6 +729,8 @@ int w1_attach_slave_device(struct w1_master *dev, struct w1_reg_num *rn) atomic_set(&sl->refcnt, 1); atomic_inc(&sl->master->refcnt); dev->slave_count++; + dev_info(&dev->dev, "Attaching one wire slave %02x.%012llx crc %02x\n", + rn->family, (unsigned long long)rn->id, rn->crc); /* slave modules need to be loaded in a context with unlocked mutex */ mutex_unlock(&dev->mutex); |