Re: [PATCH] winmate-fm07-keys: Winmate FM07/FM07P buttons

Hans de Goede
2022-03-21T10:22:52Z

Hi Daniel,

On 3/21/22 04:16, Daniel Beer wrote:
> Winmate FM07 and FM07P in-vehicle computers have a row of five buttons
> below the display. This module adds an input device that delivers key
> events when these buttons are pressed.
>
> Signed-off-by: Daniel Beer <daniel.beer@tirotech.co.nz>

Do you have control of the firmware on this device?

If yes then IMHO it would be better to implement this in ACPI
using the intel-hid fw API for this, see:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/platform/x86/intel/hid.c

Basically you create an ACPI device with one of the HIDs from
the driver. Then on button presses you do an ACPI notify on
that device with a value of 0xc0 then the driver will call
the device's _DSM (device specific ACPI) method with a GUID
of eeec56b3-4442-408f-a792-4edd4d758054 and an argument value
of INTEL_HID_DSM_HDEM_FN and then you return the event-code
for the button.

You can remap the event-codes to different KEY_FOO values using
/lib/udev/hwdb.d/60-keyboard.hwdb

Regards,

Hans

> ---
> drivers/platform/x86/Kconfig | 8 +
> drivers/platform/x86/Makefile | 3 +
> drivers/platform/x86/winmate-fm07-keys.c | 184 +++++++++++++++++++++++
> 3 files changed, 195 insertions(+)
> create mode 100644 drivers/platform/x86/winmate-fm07-keys.c
>
> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
> index 24deeeb29af2..62a5754d6ac9 100644
> --- a/drivers/platform/x86/Kconfig
> +++ b/drivers/platform/x86/Kconfig
> @@ -1138,6 +1138,14 @@ config SIEMENS_SIMATIC_IPC
> To compile this driver as a module, choose M here: the module
> will be called simatic-ipc.
>
> +config WINMATE_FM07_KEYS
> + tristate "Winmate FM07/FM07P front-panel keys driver"
> + depends on INPUT
> + help
> + Winmate FM07 and FM07P in-vehicle computers have a row of five
> + buttons below the display. This module adds an input device
> + that delivers key events when these buttons are pressed.
> +
> endif # X86_PLATFORM_DEVICES
>
> config PMC_ATOM
> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
> index c12a9b044fd8..04e7c995b838 100644
> --- a/drivers/platform/x86/Makefile
> +++ b/drivers/platform/x86/Makefile
> @@ -129,3 +129,6 @@ obj-$(CONFIG_PMC_ATOM) += pmc_atom.o
>
> # Siemens Simatic Industrial PCs
> obj-$(CONFIG_SIEMENS_SIMATIC_IPC) += simatic-ipc.o
> +
> +# Winmate
> +obj-$(CONFIG_WINMATE_FM07_KEYS) += winmate-fm07-keys.o
> diff --git a/drivers/platform/x86/winmate-fm07-keys.c b/drivers/platform/x86/winmate-fm07-keys.c
> new file mode 100644
> index 000000000000..3e75adb15444
> --- /dev/null
> +++ b/drivers/platform/x86/winmate-fm07-keys.c
> @@ -0,0 +1,184 @@
> +// SPDX-License-Identifier: GPL-2.0
> +//
> +// Driver for the Winmate FM07 front-panel keys
> +//
> +// Author: Daniel Beer <daniel.beer@tirotech.co.nz>
> +
> +#include <linux/init.h>
> +#include <linux/module.h>
> +#include <linux/input.h>
> +#include <linux/ioport.h>
> +#include <linux/platform_device.h>
> +#include <linux/dmi.h>
> +#include <linux/io.h>
> +
> +#define DRV_NAME "winmate-fm07keys"
> +
> +#define PORT_CMD 0x6c
> +#define PORT_DATA 0x68
> +
> +#define EC_ADDR_KEYS 0x3b
> +#define EC_CMD_READ 0x80
> +
> +#define BASE_KEY KEY_F13
> +#define NUM_KEYS 5
> +
> +/* Typically we're done in fewer than 10 iterations */
> +#define LOOP_TIMEOUT 1000
> +
> +static void fm07keys_poll(struct input_dev *input)
> +{
> + uint8_t k;
> + int i;
> +
> + /* Flush output buffer */
> + i = 0;
> + while (inb(PORT_CMD) & 0x01) {
> + if (++i >= LOOP_TIMEOUT)
> + goto timeout;
> + inb(PORT_DATA);
> + }
> +
> + /* Send request and wait for write completion */
> + outb(EC_CMD_READ, PORT_CMD);
> + i = 0;
> + while (inb(PORT_CMD) & 0x02)
> + if (++i >= LOOP_TIMEOUT)
> + goto timeout;
> +
> + outb(EC_ADDR_KEYS, PORT_DATA);
> + i = 0;
> + while (inb(PORT_CMD) & 0x02)
> + if (++i >= LOOP_TIMEOUT)
> + goto timeout;
> +
> + /* Wait for data ready */
> + i = 0;
> + while (!(inb(PORT_CMD) & 0x01))
> + if (++i >= LOOP_TIMEOUT)
> + goto timeout;
> + k = inb(PORT_DATA);
> +
> + /* Notify of new key states */
> + for (i = 0; i < NUM_KEYS; i++) {
> + input_report_key(input, BASE_KEY + i, (~k) & 1);
> + k >>= 1;
> + }
> +
> + input_sync(input);
> + return;
> +timeout:
> + dev_err(&input->dev, "timeout polling IO memory\n");
> +}
> +
> +static int fm07keys_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct input_dev *input;
> + int ret;
> + int i;
> +
> + input = devm_input_allocate_device(dev);
> + if (!input) {
> + dev_err(dev, "no memory for input device\n");
> + return -ENOMEM;
> + }
> +
> + if (!devm_request_region(dev, PORT_CMD, 1, "Winmate FM07 EC"))
> + return -EBUSY;
> + if (!devm_request_region(dev, PORT_DATA, 1, "Winmate FM07 EC"))
> + return -EBUSY;
> +
> + input->name = "Winmate FM07 front-panel keys";
> + input->phys = DRV_NAME "/input0";
> +
> + input->id.bustype = BUS_HOST;
> + input->id.vendor = 0x0001;
> + input->id.product = 0x0001;
> + input->id.version = 0x0100;
> +
> + __set_bit(EV_KEY, input->evbit);
> +
> + for (i = 0; i < NUM_KEYS; i++)
> + __set_bit(BASE_KEY + i, input->keybit);
> +
> + ret = input_setup_polling(input, fm07keys_poll);
> + if (ret) {
> + dev_err(dev, "unable to set up polling, err=%d\n", ret);
> + return ret;
> + }
> +
> + input_set_poll_interval(input, 20);
> +
> + ret = input_register_device(input);
> + if (ret) {
> + dev_err(dev, "unable to register polled device, err=%d\n",
> + ret);
> + return ret;
> + }
> +
> + input_sync(input);
> + return 0;
> +}
> +
> +static struct platform_driver fm07keys_driver = {
> + .probe = fm07keys_probe,
> + .driver = {
> + .name = DRV_NAME
> + },
> +};
> +
> +/************************************************************************
> + * Device instance for the FM07
> + */
> +
> +static struct platform_device *dev;
> +
> +static const struct dmi_system_id fm07keys_dmi_table[] __initconst = {
> + {
> + /* FM07 and FM07P */
> + .matches = {
> + DMI_MATCH(DMI_SYS_VENDOR, "Winmate Inc."),
> + DMI_MATCH(DMI_PRODUCT_NAME, "IP30"),
> + },
> + },
> +};
> +
> +static int __init fm07keys_init(void)
> +{
> + int ret;
> +
> + if (!dmi_check_system(fm07keys_dmi_table))
> + return -ENODEV;
> +
> + ret = platform_driver_register(&fm07keys_driver);
> + if (ret) {
> + pr_err("fm07keys: failed to register driver, err=%d\n", ret);
> + return ret;
> + }
> +
> + dev = platform_device_register_simple(DRV_NAME, -1, NULL, 0);
> + if (!dev) {
> + pr_err("fm07keys: failed to allocate device\n");
> + ret = -ENOMEM;
> + goto fail_alloc;
> + }
> +
> + return 0;
> +fail_alloc:
> + platform_driver_unregister(&fm07keys_driver);
> + return ret;
> +}
> +
> +static void __exit fm07keys_exit(void)
> +{
> + platform_driver_unregister(&fm07keys_driver);
> + platform_device_unregister(dev);
> +}
> +
> +module_init(fm07keys_init);
> +module_exit(fm07keys_exit);
> +
> +MODULE_AUTHOR("Daniel Beer <daniel.beer@tirotech.co.nz>");
> +MODULE_DESCRIPTION("Winmate FM07 front-panel keys driver");
> +MODULE_LICENSE("GPL v2");