From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
To: Wolfram Sang <wsa@the-dreams.de>
Cc: linux-i2c <linux-i2c@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
Bartosz Golaszewski <bgolaszewski@baylibre.com>
Subject: [RESEND PATCH v2 3/9] eeprom: at24: tie up an additional address for at24cs series
Date: Wed, 2 Dec 2015 11:25:20 +0100 [thread overview]
Message-ID: <1449051926-21918-4-git-send-email-bgolaszewski@baylibre.com> (raw)
In-Reply-To: <1449051926-21918-1-git-send-email-bgolaszewski@baylibre.com>
The at24cs series EEPROM chips have an additional read-only memory area,
that is visible on a different i2c slave address. Tie it up with a dummy
device.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
---
drivers/misc/eeprom/at24.c | 30 ++++++++++++++++++++++++++----
1 file changed, 26 insertions(+), 4 deletions(-)
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c
index 5d7c090..08cc327 100644
--- a/drivers/misc/eeprom/at24.c
+++ b/drivers/misc/eeprom/at24.c
@@ -103,6 +103,8 @@ MODULE_PARM_DESC(write_timeout, "Time (in ms) to try writes (default 25)");
#define AT24_BITMASK(x) (BIT(x) - 1)
+#define AT24CS_SERIAL_ADDR(addr) (addr + 0x08)
+
/* create non-zero magic value for given eeprom parameters */
#define AT24_DEVICE_MAGIC(_len, _flags) \
((1 << AT24_SIZE_FLAGS | (_flags)) \
@@ -558,6 +560,8 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
if (chip.flags & AT24_FLAG_TAKE8ADDR)
num_addresses = 8;
+ else if (chip.flags & AT24_FLAG_SERIAL)
+ num_addresses = 2;
else
num_addresses = DIV_ROUND_UP(chip.byte_len,
(chip.flags & AT24_FLAG_ADDR16) ? 65536 : 256);
@@ -616,12 +620,30 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
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,
+ if (at24->chip.flags & AT24_FLAG_TAKE8ADDR) {
+ 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);
- if (!at24->client[i]) {
+ err = -EADDRINUSE;
+ goto err_clients;
+ }
+ }
+ }
+
+ /*
+ * at24cs series tie up an additional address for the memory area
+ * contining the serial number
+ */
+ if (at24->chip.flags & AT24_FLAG_SERIAL) {
+ at24->client[1] = i2c_new_dummy(client->adapter,
+ AT24CS_SERIAL_ADDR(client->addr));
+ if (!at24->client[1]) {
dev_err(&client->dev, "address 0x%02x unavailable\n",
- client->addr + i);
+ AT24CS_SERIAL_ADDR(client->addr));
err = -EADDRINUSE;
goto err_clients;
}
--
2.1.4
next prev parent reply other threads:[~2015-12-02 10:27 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-12-02 10:25 [RESEND PATCH v2 0/9] eeprom: at24: at24cs series serial number read Bartosz Golaszewski
2015-12-02 10:25 ` [RESEND PATCH v2 1/9] eeprom: at24: platform_data: use BIT() macro Bartosz Golaszewski
2015-12-02 10:25 ` [RESEND PATCH v2 2/9] eeprom: at24: new flag in platform_data Bartosz Golaszewski
2015-12-02 10:25 ` Bartosz Golaszewski [this message]
2015-12-02 10:25 ` [RESEND PATCH v2 4/9] eeprom: at24: support reading of the serial number Bartosz Golaszewski
2015-12-02 10:25 ` [RESEND PATCH v2 5/9] eeprom: at24: export the serial number through sysfs Bartosz Golaszewski
2015-12-02 10:25 ` [RESEND PATCH v2 6/9] eeprom: at24: improve the device_id table readability Bartosz Golaszewski
2015-12-02 10:25 ` [RESEND PATCH v2 7/9] eeprom: at24: add the at24cs series to the list of supported devices Bartosz Golaszewski
2015-12-02 10:25 ` [RESEND PATCH v2 8/9] eeprom: at24: remove a reduntant if Bartosz Golaszewski
2015-12-02 10:25 ` [RESEND PATCH v2 9/9] eeprom: at24: readability tweaks Bartosz Golaszewski
2015-12-11 12:08 ` [RESEND PATCH v2 0/9] eeprom: at24: at24cs series serial number read Wolfram Sang
2015-12-11 13:55 ` Bartosz Golaszewski
2015-12-21 14:29 ` Bartosz Golaszewski
2016-01-02 20:50 ` Wolfram Sang
2016-01-04 14:01 ` Bartosz Golaszewski
2016-01-05 18:58 ` Wolfram Sang
2016-01-07 16:10 ` Bartosz Golaszewski
2016-01-09 21:09 ` Wolfram Sang
2016-01-11 13:57 ` Bartosz Golaszewski
-- strict thread matches above, loose matches on Subject: below --
2015-11-24 9:44 Bartosz Golaszewski
2015-11-24 9:44 ` [RESEND PATCH v2 3/9] eeprom: at24: tie up an additional address for at24cs series Bartosz Golaszewski
2015-11-17 9:52 [RESEND PATCH v2 0/9] eeprom: at24: at24cs series serial number read Bartosz Golaszewski
2015-11-17 9:52 ` [RESEND PATCH v2 3/9] eeprom: at24: tie up an additional address for at24cs series Bartosz Golaszewski
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