[PATCHv6 11/11] [TESTPATCH] rtc: convert ds1307 to interim probe_new

From: Kieran Bingham
Date: Tue Oct 25 2016 - 12:43:36 EST


Just for testing, specify a maxim,ds1307 device to identify the code path used
when instantiating the driver from userspace.

root@arm:~# echo maxim,ds1307 0x68 > /sys/bus/i2c/devices/i2c-2/new_device
[ 49.807383] rtc-ds1307 2-0068: I'm a Maxim ...
[ 49.814706] rtc-ds1307 2-0068: rtc core: registered maxim,ds1307 as rtc0
[ 49.821813] rtc-ds1307 2-0068: 56 bytes nvram
[ 49.826444] i2c i2c-2: new_device: Instantiated device maxim,ds1307 at 0x68

This patch also demonstrates how to obtain data from the id's using the
new methods.
---
drivers/rtc/rtc-ds1307.c | 53 ++++++++++++++++++++++++++++--------------------
1 file changed, 31 insertions(+), 22 deletions(-)

diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 8e1c5cb6ece6..f760b7cf1fdb 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -31,6 +31,7 @@
*/
enum ds_type {
ds_1307,
+ maxim_1307,
ds_1337,
ds_1338,
ds_1339,
@@ -144,6 +145,10 @@ static struct chip_desc chips[last_ds_type] = {
.nvram_offset = 8,
.nvram_size = 56,
},
+ [maxim_1307] = {
+ .nvram_offset = 8,
+ .nvram_size = 56,
+ },
[ds_1337] = {
.alarm = 1,
},
@@ -173,22 +178,6 @@ static struct chip_desc chips[last_ds_type] = {
},
};

-static const struct i2c_device_id ds1307_id[] = {
- { "ds1307", ds_1307 },
- { "ds1337", ds_1337 },
- { "ds1338", ds_1338 },
- { "ds1339", ds_1339 },
- { "ds1388", ds_1388 },
- { "ds1340", ds_1340 },
- { "ds3231", ds_3231 },
- { "m41t00", m41t00 },
- { "mcp7940x", mcp794xx },
- { "mcp7941x", mcp794xx },
- { "pt7c4338", ds_1307 },
- { "rx8025", rx_8025 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, ds1307_id);

/*----------------------------------------------------------------------*/

@@ -1223,13 +1212,20 @@ static void ds1307_clks_register(struct ds1307 *ds1307)

#endif /* CONFIG_COMMON_CLK */

-static int ds1307_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+static const struct of_device_id ds1307_dt_ids[] = {
+ { .compatible = "dallas,ds1307", .data = (void *)ds_1307 },
+ { .compatible = "maxim,ds1307", .data = (void *)maxim_1307 },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, ds1307_dt_ids);
+
+static int ds1307_probe(struct i2c_client *client)
{
struct ds1307 *ds1307;
int err = -ENODEV;
int tmp, wday;
- struct chip_desc *chip = &chips[id->driver_data];
+ const struct of_device_id *idof;
+ struct chip_desc *chip;
struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
bool want_irq = false;
bool ds1307_can_wakeup_device = false;
@@ -1255,10 +1251,20 @@ static int ds1307_probe(struct i2c_client *client,
if (!ds1307)
return -ENOMEM;

+ /* If we've got this far, this shouldn't be able to fail - but check anyway for now */
+ idof = i2c_of_match_device(ds1307_dt_ids, client);
+ if (!idof) {
+ dev_err(&client->dev, "Probe failed to find an id entry\n");
+ return -ENODEV;
+ }
+
+ /* Now we can set our chip entry */
+ chip = &chips[(int)idof->data];
+
i2c_set_clientdata(client, ds1307);

ds1307->client = client;
- ds1307->type = id->driver_data;
+ ds1307->type = (int) idof->data;

if (!pdata && client->dev.of_node)
ds1307_trickle_of_init(client, chip);
@@ -1435,6 +1441,9 @@ read_rtc:
*/
tmp = ds1307->regs[DS1307_REG_SECS];
switch (ds1307->type) {
+ case maxim_1307:
+ dev_info(&client->dev, "I'm a Maxim ... \n");
+ /* fallthrough */
case ds_1307:
case m41t00:
/* clock halted? turn it on, so clock can tick. */
@@ -1634,10 +1643,10 @@ static int ds1307_remove(struct i2c_client *client)
static struct i2c_driver ds1307_driver = {
.driver = {
.name = "rtc-ds1307",
+ .of_match_table = of_match_ptr(ds1307_dt_ids),
},
- .probe = ds1307_probe,
+ .probe_new = ds1307_probe,
.remove = ds1307_remove,
- .id_table = ds1307_id,
};

module_i2c_driver(ds1307_driver);
--
2.7.4