2016-11-23 08:53:50

by Tin Huynh

[permalink] [raw]
Subject: [PATCH V2] i2c: mux: pca954x: Add ACPI support for pca954x

From: Tin Huynh <[email protected]>

This patch enables ACPI support for mux-pca954x driver.

Signed-off-by: Tin Huynh <[email protected]>

Change from v1 :
-Don't shadow id variable.
-Include sorted header.
-Redefine acpi_device_id.
-Add CONFIG_ACPI.
---
drivers/i2c/muxes/i2c-mux-pca954x.c | 29 ++++++++++++++++++++++++++++-
1 files changed, 28 insertions(+), 1 deletions(-)

diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
index 1091346..1ad67cb 100644
--- a/drivers/i2c/muxes/i2c-mux-pca954x.c
+++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
@@ -35,6 +35,7 @@
* warranty of any kind, whether express or implied.
*/

+#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
@@ -120,6 +121,21 @@ struct pca954x {
};
MODULE_DEVICE_TABLE(i2c, pca954x_id);

+#ifdef CONFIG_ACPI
+static const struct acpi_device_id pca954x_acpi_ids[] = {
+ { .id = "PCA9540", .driver_data = pca_9540 },
+ { .id = "PCA9542", .driver_data = pca_9540 },
+ { .id = "PCA9543", .driver_data = pca_9543 },
+ { .id = "PCA9544", .driver_data = pca_9544 },
+ { .id = "PCA9545", .driver_data = pca_9545 },
+ { .id = "PCA9546", .driver_data = pca_9545 },
+ { .id = "PCA9547", .driver_data = pca_9547 },
+ { .id = "PCA9548", .driver_data = pca_9548 },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, pca954x_acpi_ids);
+#endif
+
#ifdef CONFIG_OF
static const struct of_device_id pca954x_of_match[] = {
{ .compatible = "nxp,pca9540", .data = &chips[pca_9540] },
@@ -245,8 +261,18 @@ static int pca954x_probe(struct i2c_client *client,
match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
if (match)
data->chip = of_device_get_match_data(&client->dev);
- else
+ else if (id)
data->chip = &chips[id->driver_data];
+#ifdef CONFIG_ACPI
+ else {
+ const struct acpi_device_id *acpi_id;
+
+ acpi_id = acpi_match_device(pca954x_acpi_ids, &client->dev);
+ if (!acpi_id)
+ return -ENODEV;
+ data->chip = &chips[acpi_id->driver_data];
+ }
+#endif

data->last_chan = 0; /* force the first selection */

@@ -321,6 +347,7 @@ static int pca954x_resume(struct device *dev)
.name = "pca954x",
.pm = &pca954x_pm,
.of_match_table = of_match_ptr(pca954x_of_match),
+ .acpi_match_table = ACPI_PTR(pca954x_acpi_ids),
},
.probe = pca954x_probe,
.remove = pca954x_remove,
--
1.7.1


2016-11-23 09:08:48

by Peter Rosin

[permalink] [raw]
Subject: Re: [PATCH V2] i2c: mux: pca954x: Add ACPI support for pca954x

On 2016-11-23 09:52, [email protected] wrote:
> From: Tin Huynh <[email protected]>
>
> This patch enables ACPI support for mux-pca954x driver.
>
> Signed-off-by: Tin Huynh <[email protected]>
>
> Change from v1 :
> -Don't shadow id variable.
> -Include sorted header.
> -Redefine acpi_device_id.
> -Add CONFIG_ACPI.

Please put these extra comment that do not belong in the changelog
below the following three dashes. Then git will ignore these comments
automatically, which simplifies applying the patch.

> ---
> drivers/i2c/muxes/i2c-mux-pca954x.c | 29 ++++++++++++++++++++++++++++-
> 1 files changed, 28 insertions(+), 1 deletions(-)

The customary position for extra comments is here, below the diffstat.

> diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
> index 1091346..1ad67cb 100644
> --- a/drivers/i2c/muxes/i2c-mux-pca954x.c
> +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
> @@ -35,6 +35,7 @@
> * warranty of any kind, whether express or implied.
> */
>
> +#include <linux/acpi.h>
> #include <linux/device.h>
> #include <linux/gpio/consumer.h>
> #include <linux/i2c.h>
> @@ -120,6 +121,21 @@ struct pca954x {
> };
> MODULE_DEVICE_TABLE(i2c, pca954x_id);
>
> +#ifdef CONFIG_ACPI
> +static const struct acpi_device_id pca954x_acpi_ids[] = {
> + { .id = "PCA9540", .driver_data = pca_9540 },
> + { .id = "PCA9542", .driver_data = pca_9540 },
> + { .id = "PCA9543", .driver_data = pca_9543 },
> + { .id = "PCA9544", .driver_data = pca_9544 },
> + { .id = "PCA9545", .driver_data = pca_9545 },
> + { .id = "PCA9546", .driver_data = pca_9545 },
> + { .id = "PCA9547", .driver_data = pca_9547 },
> + { .id = "PCA9548", .driver_data = pca_9548 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(acpi, pca954x_acpi_ids);
> +#endif
> +
> #ifdef CONFIG_OF
> static const struct of_device_id pca954x_of_match[] = {
> { .compatible = "nxp,pca9540", .data = &chips[pca_9540] },
> @@ -245,8 +261,18 @@ static int pca954x_probe(struct i2c_client *client,
> match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
> if (match)
> data->chip = of_device_get_match_data(&client->dev);
> - else
> + else if (id)
> data->chip = &chips[id->driver_data];
> +#ifdef CONFIG_ACPI

No, this #ifdef is not desired. If ACPI is not configured, acpi_match_device
will return NULL unconditionally and the compiler should compile the whole
else branch to be an unconditional "return -ENODEV;" and skip the dead code
at the end of the block. This is better than leaving data->chip as NULL and
oops later. It is also less cluttery to not have this extra #ifdef.

Cheers,
Peter

> + else {
> + const struct acpi_device_id *acpi_id;
> +
> + acpi_id = acpi_match_device(pca954x_acpi_ids, &client->dev);
> + if (!acpi_id)
> + return -ENODEV;
> + data->chip = &chips[acpi_id->driver_data];
> + }
> +#endif
>
> data->last_chan = 0; /* force the first selection */
>
> @@ -321,6 +347,7 @@ static int pca954x_resume(struct device *dev)
> .name = "pca954x",
> .pm = &pca954x_pm,
> .of_match_table = of_match_ptr(pca954x_of_match),
> + .acpi_match_table = ACPI_PTR(pca954x_acpi_ids),
> },
> .probe = pca954x_probe,
> .remove = pca954x_remove,
>