Re: [PATCH 09/22] Input: apanel - switch to using polled mode of input devices

From: Sven Van Asbroeck
Date: Mon Oct 21 2019 - 16:05:58 EST

Hi Dmitry, a few minor nags below, inline.

On Thu, Oct 17, 2019 at 4:42 PM Dmitry Torokhov
<dmitry.torokhov@xxxxxxxxx> wrote:
>
> We have added polled mode to the normal input devices with the intent of
> retiring input_polled_dev. This converts apanel driver to use the polling
> mode of standard input devices and removes dependency on INPUT_POLLDEV.
>
> While at it, let's convert the driver to use devm.
>
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
> ---
>
> drivers/input/misc/Kconfig | 1 -
> drivers/input/misc/apanel.c | 153 +++++++++++++++---------------------
> 2 files changed, 64 insertions(+), 90 deletions(-)
>
> diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
> index 7d9ae394e597..a6b8af69915d 100644
> --- a/drivers/input/misc/Kconfig
> +++ b/drivers/input/misc/Kconfig
> @@ -257,7 +257,6 @@ config INPUT_MMA8450
> config INPUT_APANEL
> tristate "Fujitsu Lifebook Application Panel buttons"
> depends on X86 && I2C && LEDS_CLASS
> - select INPUT_POLLDEV
> select CHECK_SIGNATURE
> help
> Say Y here for support of the Application Panel buttons, used on
> diff --git a/drivers/input/misc/apanel.c b/drivers/input/misc/apanel.c
> index 53ec40d1b90d..de0deb432fe3 100644
> --- a/drivers/input/misc/apanel.c
> +++ b/drivers/input/misc/apanel.c
> @@ -17,7 +17,7 @@
> #include <linux/module.h>
> #include <linux/ioport.h>
> #include <linux/io.h>
> -#include <linux/input-polldev.h>
> +#include <linux/input.h>
> #include <linux/i2c.h>
> #include <linux/leds.h>
>
> @@ -51,19 +51,28 @@ static enum apanel_chip device_chip[APANEL_DEV_MAX];
> #define MAX_PANEL_KEYS 12
>
> struct apanel {
> - struct input_polled_dev *ipdev;
> + struct input_dev *idev;
> struct i2c_client *client;
> unsigned short keymap[MAX_PANEL_KEYS];
> - u16 nkeys;
> + u16 nkeys;
> struct led_classdev mail_led;
> };
>
> +static unsigned short apanel_keymap[MAX_PANEL_KEYS] = {

Could this be const?

> + [0] = KEY_MAIL,
> + [1] = KEY_WWW,
> + [2] = KEY_PROG2,
> + [3] = KEY_PROG1,
>
> -static int apanel_probe(struct i2c_client *, const struct i2c_device_id *);
> + [8] = KEY_FORWARD,
> + [9] = KEY_REWIND,
> + [10] = KEY_STOPCD,
> + [11] = KEY_PLAYPAUSE,
> +};
>
> static void report_key(struct input_dev *input, unsigned keycode)
> {
> - pr_debug(APANEL ": report key %#x\n", keycode);
> + dev_dbg(input->dev.parent, "report key %#x\n", keycode);
> input_report_key(input, keycode, 1);
> input_sync(input);
>
> @@ -79,10 +88,9 @@ static void report_key(struct input_dev *input, unsigned keycode)
> * CD keys:
> * Forward (0x100), Rewind (0x200), Stop (0x400), Pause (0x800)
> */
> -static void apanel_poll(struct input_polled_dev *ipdev)
> +static void apanel_poll(struct input_dev *idev)
> {
> - struct apanel *ap = ipdev->private;
> - struct input_dev *idev = ipdev->input;
> + struct apanel *ap = input_get_drvdata(idev);
> u8 cmd = device_chip[APANEL_DEV_APPBTN] == CHIP_OZ992C ? 0 : 8;
> s32 data;
> int i;
> @@ -112,126 +120,93 @@ static int mail_led_set(struct led_classdev *led,
> return i2c_smbus_write_word_data(ap->client, 0x10, led_bits);
> }
>
> -static int apanel_remove(struct i2c_client *client)
> -{
> - struct apanel *ap = i2c_get_clientdata(client);
> -
> - if (device_chip[APANEL_DEV_LED] != CHIP_NONE)
> - led_classdev_unregister(&ap->mail_led);
> -
> - input_unregister_polled_device(ap->ipdev);
> - input_free_polled_device(ap->ipdev);
> -
> - return 0;
> -}
> -
> -static void apanel_shutdown(struct i2c_client *client)
> -{
> - apanel_remove(client);
> -}
> -
> -static const struct i2c_device_id apanel_id[] = {
> - { "fujitsu_apanel", 0 },
> - { }
> -};
> -MODULE_DEVICE_TABLE(i2c, apanel_id);
> -
> -static struct i2c_driver apanel_driver = {
> - .driver = {
> - .name = APANEL,
> - },
> - .probe = &apanel_probe,
> - .remove = &apanel_remove,
> - .shutdown = &apanel_shutdown,
> - .id_table = apanel_id,
> -};
> -
> -static struct apanel apanel = {
> - .keymap = {
> - [0] = KEY_MAIL,
> - [1] = KEY_WWW,
> - [2] = KEY_PROG2,
> - [3] = KEY_PROG1,
> -
> - [8] = KEY_FORWARD,
> - [9] = KEY_REWIND,
> - [10] = KEY_STOPCD,
> - [11] = KEY_PLAYPAUSE,
> -
> - },
> - .mail_led = {
> - .name = "mail:blue",
> - .brightness_set_blocking = mail_led_set,
> - },
> -};
> -
> -/* NB: Only one panel on the i2c. */
> static int apanel_probe(struct i2c_client *client,
> const struct i2c_device_id *id)
> {
> struct apanel *ap;
> - struct input_polled_dev *ipdev;
> struct input_dev *idev;
> u8 cmd = device_chip[APANEL_DEV_APPBTN] == CHIP_OZ992C ? 0 : 8;
> - int i, err = -ENOMEM;
> + int i, err;
>
> - ap = &apanel;
> + ap = devm_kzalloc(&client->dev, sizeof(*ap), GFP_KERNEL);
> + if (!ap)
> + return -ENOMEM;
>
> - ipdev = input_allocate_polled_device();
> - if (!ipdev)
> - goto out1;
> + idev = devm_input_allocate_device(&client->dev);
> + if (!idev)
> + return -ENOMEM;
>
> - ap->ipdev = ipdev;
> + ap->idev = idev;
> ap->client = client;
>
> i2c_set_clientdata(client, ap);
>
> err = i2c_smbus_write_word_data(client, cmd, 0);
> if (err) {
> - dev_warn(&client->dev, APANEL ": smbus write error %d\n",
> - err);
> - goto out3;
> + dev_warn(&client->dev, "smbus write error %d\n", err);
> + return err;
> }
>
> - ipdev->poll = apanel_poll;
> - ipdev->poll_interval = POLL_INTERVAL_DEFAULT;
> - ipdev->private = ap;
> + input_set_drvdata(idev, ap);
>
> - idev = ipdev->input;
> idev->name = APANEL_NAME " buttons";
> idev->phys = "apanel/input0";
> idev->id.bustype = BUS_HOST;
> - idev->dev.parent = &client->dev;
> -
> - set_bit(EV_KEY, idev->evbit);
>
> + memcpy(ap->keymap, apanel_keymap, sizeof(apanel_keymap));
> idev->keycode = ap->keymap;
> idev->keycodesize = sizeof(ap->keymap[0]);
> idev->keycodemax = (device_chip[APANEL_DEV_CDBTN] != CHIP_NONE) ? 12 : 4;
>
> + set_bit(EV_KEY, idev->evbit);
> for (i = 0; i < idev->keycodemax; i++)
> if (ap->keymap[i])
> set_bit(ap->keymap[i], idev->keybit);
>
> - err = input_register_polled_device(ipdev);
> + err = input_setup_polling(idev, apanel_poll);
> + if (err)
> + return err;
> +
> + input_set_poll_interval(idev, POLL_INTERVAL_DEFAULT);
> +
> + err = input_register_device(idev);
> if (err)
> - goto out3;
> + return err;
>
> if (device_chip[APANEL_DEV_LED] != CHIP_NONE) {
> - err = led_classdev_register(&client->dev, &ap->mail_led);
> + ap->mail_led.name = "mail:blue";
> + ap->mail_led.brightness_set_blocking = mail_led_set;
> + err = devm_led_classdev_register(&client->dev, &ap->mail_led);
> if (err)
> - goto out4;
> + return err;
> }
>
> return 0;
> -out4:
> - input_unregister_polled_device(ipdev);
> -out3:
> - input_free_polled_device(ipdev);
> -out1:
> - return err;
> }
>
> +static void apanel_shutdown(struct i2c_client *client)
> +{
> + struct apanel *ap = i2c_get_clientdata(client);
> +
> + if (device_chip[APANEL_DEV_LED] != CHIP_NONE)
> + led_set_brightness(&ap->mail_led, LED_OFF);

Is this code required? Doesn't led_class_dev_unregister()
(automatically called by devm_) switch the led off?

If it's not required, then the whole shutdown function can
be removed.

> +}
> +
> +static const struct i2c_device_id apanel_id[] = {
> + { "fujitsu_apanel", 0 },

If the driver_data field of i2c_device_id is unused, would it
be better to match via apanel_driver.driver.of_match_table ?

> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, apanel_id);
> +
> +static struct i2c_driver apanel_driver = {
> + .driver = {
> + .name = APANEL,
> + },
> + .probe = &apanel_probe,
> + .shutdown = &apanel_shutdown,

The ampersand (&) can be removed.
I realize that this is just old code that has changed position.

> + .id_table = apanel_id,
> +};
> +
> /* Scan the system ROM for the signature "FJKEYINF" */
> static __init const void __iomem *bios_signature(const void __iomem *bios)
> {
> --
> 2.23.0.866.gb869b98d4c-goog
>