iio:adc:max1363 support SMBus for 8-bit devices
The driver currently supports only I2C access. But supported devices with an
accuracy of 8-bit are compatible with the SMBus byte access routines.
This patch wraps the send and receive routines depending on the chip
accuracy and fonctionnalities of its adapter.
For instance, this allows us to use a MAX11603 on a ICH7 controller.
This patch also simplifies the max1363_write_basic_config() routine to
use the struct max1363_state fields directly.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/adc/max1363.c b/drivers/iio/adc/max1363.c
index cc07b37..6118dce 100644
--- a/drivers/iio/adc/max1363.c
+++ b/drivers/iio/adc/max1363.c
@@ -165,6 +165,8 @@
* @thresh_low: low threshold values
* @vref: Reference voltage regulator
* @vref_uv: Actual (external or internal) reference voltage
+ * @send: function used to send data to the chip
+ * @recv: function used to receive data from the chip
*/
struct max1363_state {
struct i2c_client *client;
@@ -186,6 +188,10 @@
s16 thresh_low[8];
struct regulator *vref;
u32 vref_uv;
+ int (*send)(const struct i2c_client *client,
+ const char *buf, int count);
+ int (*recv)(const struct i2c_client *client,
+ char *buf, int count);
};
#define MAX1363_MODE_SINGLE(_num, _mask) { \
@@ -311,13 +317,37 @@
return NULL;
}
-static int max1363_write_basic_config(struct i2c_client *client,
- unsigned char d1,
- unsigned char d2)
+static int max1363_smbus_send(const struct i2c_client *client, const char *buf,
+ int count)
{
- u8 tx_buf[2] = {d1, d2};
+ int i, err;
- return i2c_master_send(client, tx_buf, 2);
+ for (i = err = 0; err == 0 && i < count; ++i)
+ err = i2c_smbus_write_byte(client, buf[i]);
+
+ return err ? err : count;
+}
+
+static int max1363_smbus_recv(const struct i2c_client *client, char *buf,
+ int count)
+{
+ int i, ret;
+
+ for (i = 0; i < count; ++i) {
+ ret = i2c_smbus_read_byte(client);
+ if (ret < 0)
+ return ret;
+ buf[i] = ret;
+ }
+
+ return count;
+}
+
+static int max1363_write_basic_config(struct max1363_state *st)
+{
+ u8 tx_buf[2] = { st->setupbyte, st->configbyte };
+
+ return st->send(st->client, tx_buf, 2);
}
static int max1363_set_scan_mode(struct max1363_state *st)
@@ -327,9 +357,7 @@
| MAX1363_SE_DE_MASK);
st->configbyte |= st->current_mode->conf;
- return max1363_write_basic_config(st->client,
- st->setupbyte,
- st->configbyte);
+ return max1363_write_basic_config(st);
}
static int max1363_read_single_chan(struct iio_dev *indio_dev,
@@ -366,7 +394,7 @@
}
if (st->chip_info->bits != 8) {
/* Get reading */
- data = i2c_master_recv(client, rxbuf, 2);
+ data = st->recv(client, rxbuf, 2);
if (data < 0) {
ret = data;
goto error_ret;
@@ -375,7 +403,7 @@
((1 << st->chip_info->bits) - 1);
} else {
/* Get reading */
- data = i2c_master_recv(client, rxbuf, 1);
+ data = st->recv(client, rxbuf, 1);
if (data < 0) {
ret = data;
goto error_ret;
@@ -772,11 +800,11 @@
u8 tx[2] = { st->setupbyte,
MAX1363_MON_INT_ENABLE | (st->monitor_speed << 1) | 0xF0 };
- i2c_master_recv(st->client, &rx, 1);
+ st->recv(st->client, &rx, 1);
mask = rx;
for_each_set_bit(loc, &mask, 8)
iio_push_event(indio_dev, max1363_event_codes[loc], timestamp);
- i2c_master_send(st->client, tx, 2);
+ st->send(st->client, tx, 2);
return IRQ_HANDLED;
}
@@ -812,9 +840,7 @@
st->setupbyte &= ~MAX1363_SETUP_MONITOR_SETUP;
st->configbyte &= ~MAX1363_SCAN_MASK;
st->monitor_on = false;
- return max1363_write_basic_config(st->client,
- st->setupbyte,
- st->configbyte);
+ return max1363_write_basic_config(st);
}
/* Ensure we are in the relevant mode */
@@ -876,7 +902,7 @@
}
- ret = i2c_master_send(st->client, tx_buf, len);
+ ret = st->send(st->client, tx_buf, len);
if (ret < 0)
goto error_ret;
if (ret != len) {
@@ -893,7 +919,7 @@
*/
tx_buf[0] = st->setupbyte;
tx_buf[1] = MAX1363_MON_INT_ENABLE | (st->monitor_speed << 1) | 0xF0;
- ret = i2c_master_send(st->client, tx_buf, 2);
+ ret = st->send(st->client, tx_buf, 2);
if (ret < 0)
goto error_ret;
if (ret != 2) {
@@ -1481,9 +1507,9 @@
if (rxbuf == NULL)
goto done;
if (st->chip_info->bits != 8)
- b_sent = i2c_master_recv(st->client, rxbuf, numvals*2);
+ b_sent = st->recv(st->client, rxbuf, numvals * 2);
else
- b_sent = i2c_master_recv(st->client, rxbuf, numvals);
+ b_sent = st->recv(st->client, rxbuf, numvals);
if (b_sent < 0)
goto done_free;
@@ -1550,6 +1576,18 @@
st->vref_uv = vref_uv;
}
+ if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ st->send = i2c_master_send;
+ st->recv = i2c_master_recv;
+ } else if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE)
+ && st->chip_info->bits == 8) {
+ st->send = max1363_smbus_send;
+ st->recv = max1363_smbus_recv;
+ } else {
+ ret = -EOPNOTSUPP;
+ goto error_disable_reg;
+ }
+
ret = max1363_alloc_scan_masks(indio_dev);
if (ret)
goto error_disable_reg;