4.14-stable review patch. If anyone has any objections, please let me know.
------------------
[ Upstream commit a2b3bf4846e5eed62ea6abb096af2c950961033c ]
Provide a flexible way to determine the addressing bits of eeprom.
Pass the addressing bits to driver through address-width property.
Signed-off-by: Alan Chiang <alanx.chiang@xxxxxxxxx>
Signed-off-by: Andy Yeh <andy.yeh@xxxxxxxxx>
Signed-off-by: Bartosz Golaszewski <brgl@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/misc/eeprom/at24.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index 4cc0b42f2acc..ded48a0c77ee 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -577,6 +577,23 @@ static void at24_get_pdata(struct device *dev, struct at24_platform_data *chip)
if (device_property_present(dev, "read-only"))
chip->flags |= AT24_FLAG_READONLY;
+ err = device_property_read_u32(dev, "address-width", &val);
+ if (!err) {
+ switch (val) {
+ case 8:
+ if (chip->flags & AT24_FLAG_ADDR16)
+ dev_warn(dev, "Override address width to be 8, while default is 16\n");
+ chip->flags &= ~AT24_FLAG_ADDR16;
+ break;
+ case 16:
+ chip->flags |= AT24_FLAG_ADDR16;
+ break;
+ default:
+ dev_warn(dev, "Bad \"address-width\" property: %u\n",
+ val);
+ }
+ }
+
err = device_property_read_u32(dev, "pagesize", &val);
if (!err) {
chip->page_size = val;
--
2.17.1
