misc: at25: Parse dt settings

This adds dt support to the at25 eeprom driver.

Signed-off-by: Alexandre Pereira da Silva <aletes.xgr@gmail.com>
Tested-by: Roland Stigge <stigge@antcom.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 45 insertions, 16 deletions

diff --git a/drivers/misc/eeprom/at25.c b/drivers/misc/eeprom/at25.c
index 0842c2994ee2..25003d6ceb56 100644
--- a/drivers/misc/eeprom/at25.c
+++ b/drivers/misc/eeprom/at25.c
@@ -19,7 +19,7 @@
 
 #include <linux/spi/spi.h>
 #include <linux/spi/eeprom.h>
-
+#include <linux/of.h>
 
 /*
  * NOTE: this is an *EEPROM* driver.  The vagaries of product naming
@@ -305,25 +305,54 @@ static ssize_t at25_mem_write(struct memory_accessor *mem, const char *buf,
 static int at25_probe(struct spi_device *spi)
 {
         struct at25_data        *at25 = NULL;
-        const struct spi_eeprom *chip;
+        struct spi_eeprom       chip;
+        struct device_node      *np = spi->dev.of_node;
         int                     err;
         int                     sr;
         int                     addrlen;
 
         /* Chip description */
-        chip = spi->dev.platform_data;
-        if (!chip) {
-                dev_dbg(&spi->dev, "no chip description\n");
-                err = -ENODEV;
-                goto fail;
-        }
+        if (!spi->dev.platform_data) {
+                if (np) {
+                        u32 val;
+
+                        memset(&chip, 0, sizeof(chip));
+                        strncpy(chip.name, np->name, 10);
+
+                        err = of_property_read_u32(np, "at25,byte-len", &val);
+                        if (err) {
+                                dev_dbg(&spi->dev, "invalid chip dt description\n");
+                                goto fail;
+                        }
+                        chip.byte_len = val;
+
+                        err = of_property_read_u32(np, "at25,addr-mode", &val);
+                        if (err) {
+                                dev_dbg(&spi->dev, "invalid chip dt description\n");
+                                goto fail;
+                        }
+                        chip.flags = (u16)val;
+
+                        err = of_property_read_u32(np, "at25,page-size", &val);
+                        if (err) {
+                                dev_dbg(&spi->dev, "invalid chip dt description\n");
+                                goto fail;
+                        }
+                        chip.page_size = (u16)val;
+                } else {
+                        dev_dbg(&spi->dev, "no chip description\n");
+                        err = -ENODEV;
+                        goto fail;
+                }
+        } else
+                chip = *(struct spi_eeprom *)spi->dev.platform_data;
 
         /* For now we only support 8/16/24 bit addressing */
-        if (chip->flags & EE_ADDR1)
+        if (chip.flags & EE_ADDR1)
                 addrlen = 1;
-        else if (chip->flags & EE_ADDR2)
+        else if (chip.flags & EE_ADDR2)
                 addrlen = 2;
-        else if (chip->flags & EE_ADDR3)
+        else if (chip.flags & EE_ADDR3)
                 addrlen = 3;
         else {
                 dev_dbg(&spi->dev, "unsupported address type\n");
@@ -348,7 +377,7 @@ static int at25_probe(struct spi_device *spi)
         }
 
         mutex_init(&at25->lock);
-        at25->chip = *chip;
+        at25->chip = chip;
         at25->spi = spi_dev_get(spi);
         dev_set_drvdata(&spi->dev, at25);
         at25->addrlen = addrlen;
@@ -369,7 +398,7 @@ static int at25_probe(struct spi_device *spi)
         at25->mem.read = at25_mem_read;
 
         at25->bin.size = at25->chip.byte_len;
-        if (!(chip->flags & EE_READONLY)) {
+        if (!(chip.flags & EE_READONLY)) {
                 at25->bin.write = at25_bin_write;
                 at25->bin.attr.mode |= S_IWUSR;
                 at25->mem.write = at25_mem_write;
@@ -379,8 +408,8 @@ static int at25_probe(struct spi_device *spi)
         if (err)
                 goto fail;
 
-        if (chip->setup)
-                chip->setup(&at25->mem, chip->context);
+        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)
@@ -388,7 +417,7 @@ static int at25_probe(struct spi_device *spi)
                         : (at25->bin.size / 1024),
                 (at25->bin.size < 1024) ? "Byte" : "KByte",
                 at25->chip.name,
-                (chip->flags & EE_READONLY) ? " (readonly)" : "",
+                (chip.flags & EE_READONLY) ? " (readonly)" : "",
                 at25->chip.page_size);
         return 0;
 fail: