From: Jose Cazarin <joseespiriki@xxxxxxxxx>
When matching an OF device, the match mechanism tries all components of
the compatible property. This can result with a device matched with a
compatible string that isn't the first in the compatible list. For
instance, with a compatible property set to
compatible = "ti,dac081c081", "ti,dac5571";
the driver will match the second compatible string, as the first one
isn't listed in the of_device_id table. The device will however be named
"dac081c081" by the I2C core.
This causes an issue when identifying the chip. The probe function
receives a i2c_device_id that comes from the module's I2C device ID
table. There is no entry in that table for "dac081c081", which results
in a NULL pointer passed to the probe function.
To fix this, add chip_id information in the data field of the OF device
ID table, and retrieve it with of_device_get_match_data() for OF
devices.
Signed-off-by: Jose Cazarin <joseespiriki@xxxxxxxxx>
Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
---
Changes since v1:
- Include linux/of_device.h
---
drivers/iio/dac/ti-dac5571.c | 28 ++++++++++++++++++----------
1 file changed, 18 insertions(+), 10 deletions(-)
diff --git a/drivers/iio/dac/ti-dac5571.c b/drivers/iio/dac/ti-dac5571.c
index 2a5ba1b08a1d..8ceb1b42b14e 100644
--- a/drivers/iio/dac/ti-dac5571.c
+++ b/drivers/iio/dac/ti-dac5571.c
@@ -19,6 +19,7 @@
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
+#include <linux/of_device.h>
#include <linux/regulator/consumer.h>
enum chip_id {
@@ -311,6 +312,7 @@ static int dac5571_probe(struct i2c_client *client,
const struct dac5571_spec *spec;
struct dac5571_data *data;
struct iio_dev *indio_dev;
+ enum chip_id chip_id;
int ret, i;
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
@@ -326,7 +328,13 @@ static int dac5571_probe(struct i2c_client *client,
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = dac5571_channels;
- spec = &dac5571_spec[id->driver_data];
+ if (dev->of_node)
+ chip_id = (uintptr_t)of_device_get_match_data(dev);
+ else
+ chip_id = id->driver_data;
+
+ spec = &dac5571_spec[chip_id];
+
indio_dev->num_channels = spec->num_channels;
data->spec = spec;
@@ -384,15 +392,15 @@ static int dac5571_remove(struct i2c_client *i2c)
}
static const struct of_device_id dac5571_of_id[] = {
- {.compatible = "ti,dac5571"},
- {.compatible = "ti,dac6571"},
- {.compatible = "ti,dac7571"},
- {.compatible = "ti,dac5574"},
- {.compatible = "ti,dac6574"},
- {.compatible = "ti,dac7574"},
- {.compatible = "ti,dac5573"},
- {.compatible = "ti,dac6573"},
- {.compatible = "ti,dac7573"},
+ {.compatible = "ti,dac5571", .data = (void *)single_8bit},
+ {.compatible = "ti,dac6571", .data = (void *)single_10bit},
+ {.compatible = "ti,dac7571", .data = (void *)single_12bit},
+ {.compatible = "ti,dac5574", .data = (void *)quad_8bit},
+ {.compatible = "ti,dac6574", .data = (void *)quad_10bit},
+ {.compatible = "ti,dac7574", .data = (void *)quad_12bit},
+ {.compatible = "ti,dac5573", .data = (void *)quad_8bit},
+ {.compatible = "ti,dac6573", .data = (void *)quad_10bit},
+ {.compatible = "ti,dac7573", .data = (void *)quad_12bit},
{}
};
MODULE_DEVICE_TABLE(of, dac5571_of_id);
--
Regards,
Laurent Pinchart
