[PATCH 3/4] hwmon: (pmbus/mp2856) Let enum chips start with index 0

From: Guenter Roeck
Date: Mon Jun 10 2024 - 14:12:03 EST


Earlier it was assumed that the data pointer in of_device_id must not start
with 0 (NULL) if i2c_get_match_data() is used. However, it turns out that
this is perfectly fine as long as there is also an i2c_device_id array with
the same data, which is used as fallback in that case.

Let enum chips start with 0 to avoid confusion against other drivers
where the enum starts with 0 and i2c_get_match_data() is used as well.

While doing that, remove chip_id from struct mp2856_data since it is only
used in the probe function, and typecast the result of i2c_get_match_data()
to kernel_ulong_t to avoid the double typecast.

Cc: Peter Yin <peteryin.openbmc@xxxxxxxxx>
Cc: Potin Lai <potin.lai.pt@xxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
drivers/hwmon/pmbus/mp2856.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/hwmon/pmbus/mp2856.c b/drivers/hwmon/pmbus/mp2856.c
index 6969350f5d7d..41bb86667091 100644
--- a/drivers/hwmon/pmbus/mp2856.c
+++ b/drivers/hwmon/pmbus/mp2856.c
@@ -46,7 +46,7 @@

#define MP2856_PAGE_NUM 2

-enum chips { mp2856 = 1, mp2857 };
+enum chips { mp2856, mp2857 };

static const int mp2856_max_phases[][MP2856_PAGE_NUM] = {
[mp2856] = { MP2856_MAX_PHASE_RAIL1, MP2856_MAX_PHASE_RAIL2 },
@@ -66,7 +66,6 @@ struct mp2856_data {
int vout_format[MP2856_PAGE_NUM];
int curr_sense_gain[MP2856_PAGE_NUM];
int max_phases[MP2856_PAGE_NUM];
- enum chips chip_id;
};

#define to_mp2856_data(x) container_of(x, struct mp2856_data, info)
@@ -397,6 +396,7 @@ static int mp2856_probe(struct i2c_client *client)
{
struct pmbus_driver_info *info;
struct mp2856_data *data;
+ enum chips chip_id;
int ret;

data = devm_kzalloc(&client->dev, sizeof(struct mp2856_data),
@@ -404,9 +404,9 @@ static int mp2856_probe(struct i2c_client *client)
if (!data)
return -ENOMEM;

- data->chip_id = (enum chips)(uintptr_t)i2c_get_match_data(client);
+ chip_id = (kernel_ulong_t)i2c_get_match_data(client);

- memcpy(data->max_phases, mp2856_max_phases[data->chip_id],
+ memcpy(data->max_phases, mp2856_max_phases[chip_id],
sizeof(data->max_phases));

memcpy(&data->info, &mp2856_info, sizeof(*info));
--
2.39.2