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Diffstat (limited to 'drivers/misc/eeprom/at25.c')
-rw-r--r--drivers/misc/eeprom/at25.c722
1 files changed, 398 insertions, 324 deletions
diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c
index 840b3594a5ae..883dfd0ed658 100644
--- a/drivers/misc/eeprom/at25.c
+++ b/drivers/misc/eeprom/at25.c
@@ -1,40 +1,49 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
- * at25.c -- support most SPI EEPROMs, such as Atmel AT25 models
+ * Driver for most of the SPI EEPROMs, such as Atmel AT25 models
+ * and Cypress FRAMs FM25 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/init.h>
-#include <linux/module.h>
-#include <linux/slab.h>
+#include <linux/bits.h>
+#include <linux/cleanup.h>
#include <linux/delay.h>
#include <linux/device.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/property.h>
#include <linux/sched.h>
+#include <linux/slab.h>
-#include <linux/spi/spi.h>
#include <linux/spi/eeprom.h>
-#include <linux/of.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+
+#include <linux/nvmem-provider.h>
/*
- * NOTE: this is an *EEPROM* driver. The vagaries of product naming
+ * 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!
+ *
+ * EEPROMs that can be used with this driver include, for example:
+ * AT25M02, AT25128B
*/
+#define FM25_SN_LEN 8 /* serial number length */
+#define EE_MAXADDRLEN 3 /* 24 bit addresses, up to 2 MBytes */
+
struct at25_data {
- struct spi_device *spi;
- struct memory_accessor mem;
- struct mutex lock;
struct spi_eeprom chip;
- struct bin_attribute bin;
+ struct spi_mem *spimem;
+ struct mutex lock;
unsigned addrlen;
+ struct nvmem_config nvmem_config;
+ struct nvmem_device *nvmem;
+ u8 sernum[FM25_SN_LEN];
};
#define AT25_WREN 0x06 /* latch the write enable */
@@ -43,6 +52,9 @@ struct at25_data {
#define AT25_WRSR 0x01 /* write status register */
#define AT25_READ 0x03 /* read byte(s) */
#define AT25_WRITE 0x02 /* write byte(s)/sector */
+#define FM25_SLEEP 0xb9 /* enter sleep mode */
+#define FM25_RDID 0x9f /* read device ID */
+#define FM25_RDSN 0xc3 /* read S/N */
#define AT25_SR_nRDY 0x01 /* nRDY = write-in-progress */
#define AT25_SR_WEN 0x02 /* write enable (latched) */
@@ -50,11 +62,12 @@ struct at25_data {
#define AT25_SR_BP1 0x08
#define AT25_SR_WPEN 0x80 /* writeprotect enable */
-#define AT25_INSTR_BIT3 0x08 /* Additional address bit in instr */
+#define AT25_INSTR_BIT3 0x08 /* additional address bit in instr */
-#define EE_MAXADDRLEN 3 /* 24 bit addresses, up to 2 MBytes */
+#define FM25_ID_LEN 9 /* ID length */
-/* Specs often allow 5 msec for a page write, sometimes 20 msec;
+/*
+ * Specs often allow 5ms for a page write, sometimes 20ms;
* it's important to recover from write timeouts.
*/
#define EE_TIMEOUT 25
@@ -63,279 +76,283 @@ struct at25_data {
#define io_limit PAGE_SIZE /* bytes */
-static ssize_t
-at25_ee_read(
- struct at25_data *at25,
- char *buf,
- unsigned offset,
- size_t count
-)
+/* Handle the address MSB as part of instruction byte */
+static u8 at25_instr(struct at25_data *at25, u8 instr, unsigned int off)
{
- 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 (!(at25->chip.flags & EE_INSTR_BIT3_IS_ADDR))
+ return instr;
+ if (off < BIT(at25->addrlen * 8))
+ return instr;
+ return instr | AT25_INSTR_BIT3;
+}
+
+static int at25_ee_read(void *priv, unsigned int offset,
+ void *val, size_t count)
+{
+ u8 *bounce __free(kfree) = kmalloc(min(count, io_limit), GFP_KERNEL);
+ struct at25_data *at25 = priv;
+ char *buf = val;
+ unsigned int msg_offset = offset;
+ size_t bytes_left = count;
+ size_t segment;
+ int status;
+
+ if (!bounce)
+ return -ENOMEM;
+
+ if (unlikely(offset >= at25->chip.byte_len))
+ return -EINVAL;
+ if ((offset + count) > at25->chip.byte_len)
+ count = at25->chip.byte_len - 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;
- }
+ return -EINVAL;
- spi_message_init(&m);
- memset(t, 0, sizeof t);
+ do {
+ struct spi_mem_op op;
- t[0].tx_buf = command;
- t[0].len = at25->addrlen + 1;
- spi_message_add_tail(&t[0], &m);
+ segment = min(bytes_left, io_limit);
- t[1].rx_buf = buf;
- t[1].len = count;
- spi_message_add_tail(&t[1], &m);
+ op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(at25_instr(at25, AT25_READ,
+ msg_offset), 1),
+ SPI_MEM_OP_ADDR(at25->addrlen, msg_offset, 1),
+ SPI_MEM_OP_NO_DUMMY,
+ SPI_MEM_OP_DATA_IN(segment, bounce, 1));
- mutex_lock(&at25->lock);
+ status = spi_mem_adjust_op_size(at25->spimem, &op);
+ if (status)
+ return status;
+ segment = op.data.nbytes;
- /* 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_lock(&at25->lock);
+ status = spi_mem_exec_op(at25->spimem, &op);
+ mutex_unlock(&at25->lock);
+ if (status)
+ return status;
+ memcpy(buf, bounce, segment);
- mutex_unlock(&at25->lock);
- return status ? status : count;
+ msg_offset += segment;
+ buf += segment;
+ bytes_left -= segment;
+ } while (bytes_left > 0);
+
+ dev_dbg(&at25->spimem->spi->dev, "read %zu bytes at %d\n",
+ count, offset);
+ return 0;
}
-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)
+/*
+ * Read extra registers as ID or serial number
+ *
+ * Allow for the callers to provide @buf on stack (not necessary DMA-capable)
+ * by allocating a bounce buffer internally.
+ */
+static int fm25_aux_read(struct at25_data *at25, u8 *buf, uint8_t command,
+ int len)
{
- struct device *dev;
- struct at25_data *at25;
+ u8 *bounce __free(kfree) = kmalloc(len, GFP_KERNEL);
+ struct spi_mem_op op;
+ int status;
- dev = container_of(kobj, struct device, kobj);
- at25 = dev_get_drvdata(dev);
+ if (!bounce)
+ return -ENOMEM;
- return at25_ee_read(at25, buf, off, count);
+ op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(command, 1),
+ SPI_MEM_OP_NO_ADDR,
+ SPI_MEM_OP_NO_DUMMY,
+ SPI_MEM_OP_DATA_IN(len, bounce, 1));
+
+ status = spi_mem_exec_op(at25->spimem, &op);
+ dev_dbg(&at25->spimem->spi->dev, "read %d aux bytes --> %d\n", len, status);
+ if (status)
+ return status;
+
+ memcpy(buf, bounce, len);
+
+ return 0;
+}
+
+static ssize_t sernum_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct at25_data *at25;
+
+ at25 = dev_get_drvdata(dev);
+ return sysfs_emit(buf, "%*ph\n", (int)sizeof(at25->sernum), at25->sernum);
}
+static DEVICE_ATTR_RO(sernum);
+
+static struct attribute *sernum_attrs[] = {
+ &dev_attr_sernum.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(sernum);
+
+/*
+ * Poll Read Status Register with timeout
+ *
+ * Return:
+ * 0, if the chip is ready
+ * [positive] Status Register value as-is, if the chip is busy
+ * [negative] error code in case of read failure
+ */
+static int at25_wait_ready(struct at25_data *at25)
+{
+ u8 *bounce __free(kfree) = kmalloc(1, GFP_KERNEL);
+ struct spi_mem_op op;
+ int status;
+
+ if (!bounce)
+ return -ENOMEM;
+ op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(AT25_RDSR, 1),
+ SPI_MEM_OP_NO_ADDR,
+ SPI_MEM_OP_NO_DUMMY,
+ SPI_MEM_OP_DATA_IN(1, bounce, 1));
+
+ read_poll_timeout(spi_mem_exec_op, status,
+ status || !(bounce[0] & AT25_SR_nRDY), false,
+ USEC_PER_MSEC, USEC_PER_MSEC * EE_TIMEOUT,
+ at25->spimem, &op);
+ if (status < 0)
+ return status;
+ if (!(bounce[0] & AT25_SR_nRDY))
+ return 0;
+
+ return bounce[0];
+}
-static ssize_t
-at25_ee_write(struct at25_data *at25, const char *buf, loff_t off,
- size_t count)
+static int at25_ee_write(void *priv, unsigned int off, void *val, size_t count)
{
- ssize_t status = 0;
- unsigned written = 0;
- unsigned buf_size;
- u8 *bounce;
+ u8 *bounce __free(kfree) = kmalloc(min(count, io_limit), GFP_KERNEL);
+ struct at25_data *at25 = priv;
+ const char *buf = val;
+ unsigned int buf_size;
+ int status;
- if (unlikely(off >= at25->bin.size))
+ if (unlikely(off >= at25->chip.byte_len))
return -EFBIG;
- if ((off + count) > at25->bin.size)
- count = at25->bin.size - off;
+ if ((off + count) > at25->chip.byte_len)
+ count = at25->chip.byte_len - off;
if (unlikely(!count))
- return count;
+ return -EINVAL;
- /* 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
+ /*
+ * 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);
+ guard(mutex)(&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;
- }
+ struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(AT25_WREN, 1),
+ SPI_MEM_OP_NO_ADDR,
+ SPI_MEM_OP_NO_DUMMY,
+ SPI_MEM_OP_NO_DATA);
+ unsigned int segment;
- 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;
+ status = spi_mem_exec_op(at25->spimem, &op);
+ if (status < 0) {
+ dev_dbg(&at25->spimem->spi->dev, "WREN --> %d\n", status);
+ return status;
}
/* Write as much of a page as we can */
- segment = buf_size - (offset % buf_size);
+ segment = buf_size - (off % 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...
+ if (segment > io_limit)
+ segment = io_limit;
+
+ op = (struct spi_mem_op)SPI_MEM_OP(SPI_MEM_OP_CMD(at25_instr(at25, AT25_WRITE, off),
+ 1),
+ SPI_MEM_OP_ADDR(at25->addrlen, off, 1),
+ SPI_MEM_OP_NO_DUMMY,
+ SPI_MEM_OP_DATA_OUT(segment, bounce, 1));
+
+ status = spi_mem_adjust_op_size(at25->spimem, &op);
+ if (status)
+ return status;
+ segment = op.data.nbytes;
+
+ memcpy(bounce, buf, segment);
+
+ status = spi_mem_exec_op(at25->spimem, &op);
+ dev_dbg(&at25->spimem->spi->dev, "write %u bytes at %u --> %d\n",
+ segment, off, status);
+ if (status)
+ return status;
+
+ /*
+ * REVISIT this should detect (or prevent) failed writes
+ * to read-only 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;
+ status = at25_wait_ready(at25);
+ if (status < 0) {
+ dev_err_probe(&at25->spimem->spi->dev, status,
+ "Read Status Redister command failed\n");
+ return status;
+ }
+ if (status) {
+ dev_dbg(&at25->spimem->spi->dev,
+ "Status %02x\n", status);
+ dev_err(&at25->spimem->spi->dev,
+ "write %u bytes offset %u, timeout after %u msecs\n",
+ segment, off, EE_TIMEOUT);
+ return -ETIMEDOUT;
}
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);
+ return status;
}
/*-------------------------------------------------------------------------*/
-/* 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_np_to_chip(struct device *dev,
- struct device_node *np,
- struct spi_eeprom *chip)
+static int at25_fw_to_chip(struct device *dev, struct spi_eeprom *chip)
{
u32 val;
+ int err;
- memset(chip, 0, sizeof(*chip));
- strncpy(chip->name, np->name, sizeof(chip->name));
+ strscpy(chip->name, "at25", sizeof(chip->name));
- if (of_property_read_u32(np, "size", &val) == 0 ||
- of_property_read_u32(np, "at25,byte-len", &val) == 0) {
- chip->byte_len = val;
- } else {
+ err = device_property_read_u32(dev, "size", &val);
+ if (err)
+ err = device_property_read_u32(dev, "at25,byte-len", &val);
+ if (err) {
dev_err(dev, "Error: missing \"size\" property\n");
- return -ENODEV;
+ return err;
}
+ chip->byte_len = val;
- if (of_property_read_u32(np, "pagesize", &val) == 0 ||
- of_property_read_u32(np, "at25,page-size", &val) == 0) {
- chip->page_size = (u16)val;
- } else {
+ err = device_property_read_u32(dev, "pagesize", &val);
+ if (err)
+ err = device_property_read_u32(dev, "at25,page-size", &val);
+ if (err) {
dev_err(dev, "Error: missing \"pagesize\" property\n");
- return -ENODEV;
+ return err;
}
-
- if (of_property_read_u32(np, "at25,addr-mode", &val) == 0) {
+ chip->page_size = val;
+
+ err = device_property_read_u32(dev, "address-width", &val);
+ if (err) {
+ err = device_property_read_u32(dev, "at25,addr-mode", &val);
+ if (err) {
+ dev_err(dev, "Error: missing \"address-width\" property\n");
+ return err;
+ }
chip->flags = (u16)val;
} else {
- if (of_property_read_u32(np, "address-width", &val)) {
- dev_err(dev,
- "Error: missing \"address-width\" property\n");
- return -ENODEV;
- }
switch (val) {
+ case 9:
+ chip->flags |= EE_INSTR_BIT3_IS_ADDR;
+ fallthrough;
case 8:
chip->flags |= EE_ADDR1;
break;
@@ -351,129 +368,186 @@ static int at25_np_to_chip(struct device *dev,
val);
return -ENODEV;
}
- if (of_find_property(np, "read-only", NULL))
+ if (device_property_present(dev, "read-only"))
chip->flags |= EE_READONLY;
}
return 0;
}
-static int at25_probe(struct spi_device *spi)
+static int at25_fram_to_chip(struct device *dev, struct spi_eeprom *chip)
{
- struct at25_data *at25 = NULL;
- struct spi_eeprom chip;
- struct device_node *np = spi->dev.of_node;
- int err;
- int sr;
- int addrlen;
+ struct at25_data *at25 = container_of(chip, struct at25_data, chip);
+ u8 sernum[FM25_SN_LEN];
+ u8 id[FM25_ID_LEN];
+ u32 val;
+ int i;
- /* Chip description */
- if (!spi->dev.platform_data) {
- if (np) {
- err = at25_np_to_chip(&spi->dev, np, &chip);
- if (err)
- return err;
- } else {
- dev_err(&spi->dev, "Error: no chip description\n");
+ strscpy(chip->name, "fm25", sizeof(chip->name));
+
+ if (!device_property_read_u32(dev, "size", &val)) {
+ chip->byte_len = val;
+ } else {
+ /* Get ID of chip */
+ fm25_aux_read(at25, id, FM25_RDID, FM25_ID_LEN);
+ /* There are inside-out FRAM variations, detect them and reverse the ID bytes */
+ if (id[6] == 0x7f && id[2] == 0xc2)
+ for (i = 0; i < ARRAY_SIZE(id) / 2; i++) {
+ u8 tmp = id[i];
+ int j = ARRAY_SIZE(id) - i - 1;
+
+ id[i] = id[j];
+ id[j] = tmp;
+ }
+ if (id[6] != 0xc2) {
+ dev_err(dev, "Error: no Cypress FRAM with device ID (manufacturer ID bank 7: %02x)\n", id[6]);
return -ENODEV;
}
- } 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;
- }
+ switch (id[7]) {
+ case 0x21 ... 0x26:
+ chip->byte_len = BIT(id[7] - 0x21 + 4) * 1024;
+ break;
+ case 0x2a ... 0x30:
+ /* CY15B102QN ... CY15B116QN */
+ chip->byte_len = BIT(((id[7] >> 1) & 0xf) + 13);
+ break;
+ default:
+ dev_err(dev, "Error: unsupported size (id %02x)\n", id[7]);
+ return -ENODEV;
+ }
- /* 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;
+ if (id[8]) {
+ fm25_aux_read(at25, sernum, FM25_RDSN, FM25_SN_LEN);
+ /* Swap byte order */
+ for (i = 0; i < FM25_SN_LEN; i++)
+ at25->sernum[i] = sernum[FM25_SN_LEN - 1 - i];
+ }
}
- at25 = devm_kzalloc(&spi->dev, sizeof(struct at25_data), GFP_KERNEL);
+ if (chip->byte_len > 64 * 1024)
+ chip->flags |= EE_ADDR3;
+ else
+ chip->flags |= EE_ADDR2;
+
+ chip->page_size = PAGE_SIZE;
+ return 0;
+}
+
+static const struct of_device_id at25_of_match[] = {
+ { .compatible = "atmel,at25" },
+ { .compatible = "cypress,fm25" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, at25_of_match);
+
+static const struct spi_device_id at25_spi_ids[] = {
+ { .name = "at25" },
+ { .name = "fm25" },
+ { }
+};
+MODULE_DEVICE_TABLE(spi, at25_spi_ids);
+
+static int at25_probe(struct spi_mem *mem)
+{
+ struct spi_device *spi = mem->spi;
+ struct spi_eeprom *pdata;
+ struct at25_data *at25;
+ bool is_fram;
+ int err;
+
+ at25 = devm_kzalloc(&spi->dev, sizeof(*at25), 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.
+ at25->spimem = mem;
+
+ /*
+ * Ping the chip ... the status register is pretty portable,
+ * unlike probing manufacturer IDs.
*/
- 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 = at25_wait_ready(at25);
+ if (err < 0)
+ return dev_err_probe(&spi->dev, err, "Read Status Register command failed\n");
+ if (err) {
+ dev_err(&spi->dev, "Not ready (%02x)\n", err);
+ return -ENXIO;
}
- err = sysfs_create_bin_file(&spi->dev.kobj, &at25->bin);
- if (err)
- return err;
+ mutex_init(&at25->lock);
+ spi_set_drvdata(spi, at25);
- 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;
-}
+ is_fram = fwnode_device_is_compatible(dev_fwnode(&spi->dev), "cypress,fm25");
-static int at25_remove(struct spi_device *spi)
-{
- struct at25_data *at25;
+ /* Chip description */
+ pdata = dev_get_platdata(&spi->dev);
+ if (pdata) {
+ at25->chip = *pdata;
+ } else {
+ if (is_fram)
+ err = at25_fram_to_chip(&spi->dev, &at25->chip);
+ else
+ err = at25_fw_to_chip(&spi->dev, &at25->chip);
+ if (err)
+ return err;
+ }
+
+ /* For now we only support 8/16/24 bit addressing */
+ if (at25->chip.flags & EE_ADDR1)
+ at25->addrlen = 1;
+ else if (at25->chip.flags & EE_ADDR2)
+ at25->addrlen = 2;
+ else if (at25->chip.flags & EE_ADDR3)
+ at25->addrlen = 3;
+ else {
+ dev_dbg(&spi->dev, "unsupported address type\n");
+ return -EINVAL;
+ }
- at25 = spi_get_drvdata(spi);
- sysfs_remove_bin_file(&spi->dev.kobj, &at25->bin);
+ at25->nvmem_config.type = is_fram ? NVMEM_TYPE_FRAM : NVMEM_TYPE_EEPROM;
+ at25->nvmem_config.name = dev_name(&spi->dev);
+ at25->nvmem_config.dev = &spi->dev;
+ at25->nvmem_config.read_only = at25->chip.flags & EE_READONLY;
+ at25->nvmem_config.root_only = true;
+ at25->nvmem_config.owner = THIS_MODULE;
+ at25->nvmem_config.compat = true;
+ at25->nvmem_config.base_dev = &spi->dev;
+ at25->nvmem_config.reg_read = at25_ee_read;
+ at25->nvmem_config.reg_write = at25_ee_write;
+ at25->nvmem_config.priv = at25;
+ at25->nvmem_config.stride = 1;
+ at25->nvmem_config.word_size = 1;
+ at25->nvmem_config.size = at25->chip.byte_len;
+
+ at25->nvmem = devm_nvmem_register(&spi->dev, &at25->nvmem_config);
+ if (IS_ERR(at25->nvmem))
+ return PTR_ERR(at25->nvmem);
+
+ dev_info(&spi->dev, "%d %s %s %s%s, pagesize %u\n",
+ (at25->chip.byte_len < 1024) ?
+ at25->chip.byte_len : (at25->chip.byte_len / 1024),
+ (at25->chip.byte_len < 1024) ? "Byte" : "KByte",
+ at25->chip.name, is_fram ? "fram" : "eeprom",
+ (at25->chip.flags & EE_READONLY) ? " (readonly)" : "",
+ at25->chip.page_size);
return 0;
}
/*-------------------------------------------------------------------------*/
-static struct spi_driver at25_driver = {
- .driver = {
- .name = "at25",
- .owner = THIS_MODULE,
+static struct spi_mem_driver at25_driver = {
+ .spidrv = {
+ .driver = {
+ .name = "at25",
+ .of_match_table = at25_of_match,
+ .dev_groups = sernum_groups,
+ },
+ .id_table = at25_spi_ids,
},
.probe = at25_probe,
- .remove = at25_remove,
};
-module_spi_driver(at25_driver);
+module_spi_mem_driver(at25_driver);
MODULE_DESCRIPTION("Driver for most SPI EEPROMs");
MODULE_AUTHOR("David Brownell");
MODULE_LICENSE("GPL");
-MODULE_ALIAS("spi:at25");