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Date: Mon, 8 Apr 2019 15:33:43 +0300
From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To: Ronald Tschalär <ronald@...ovation.ch>
Cc: Dmitry Torokhov <dmitry.torokhov@...il.com>,
Henrik Rydberg <rydberg@...math.org>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Lukas Wunner <lukas@...ner.de>,
Federico Lorenzi <federico@...velground.com>,
linux-input@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v4 2/2] Input: add Apple SPI keyboard and trackpad driver.
On Sat, Apr 06, 2019 at 10:03:58PM -0700, Ronald Tschalär wrote:
> The keyboard and trackpad on recent MacBook's (since 8,1) and
> MacBookPro's (13,* and 14,*) are attached to an SPI controller instead
> of USB, as previously. The higher level protocol is not publicly
> documented and hence has been reverse engineered. As a consequence there
> are still a number of unknown fields and commands. However, the known
> parts have been working well and received extensive testing and use.
>
> In order for this driver to work, the proper SPI drivers need to be
> loaded too; for MB8,1 these are spi_pxa2xx_platform and spi_pxa2xx_pci;
> for all others they are spi_pxa2xx_platform and intel_lpss_pci. For this
> reason enabling this driver in the config implies enabling the above
> drivers.
Thank you for an update, my comments below.
> +static void applespi_debug_update_dimensions(struct applespi_data *applespi,
> + const struct tp_finger *f)
> +{
> + #define UPDATE_DIMENSIONS(val, op, last) \
> + do { \
> + if (le16_to_int(val) op last) \
> + last = le16_to_int(val); \
> + } while (0)
I do not see how this is better than min()/max()/min_t()/max_t().
> +
> + UPDATE_DIMENSIONS(f->abs_x, <, applespi->tp_dim_min_x);
> + UPDATE_DIMENSIONS(f->abs_x, >, applespi->tp_dim_max_x);
> + UPDATE_DIMENSIONS(f->abs_y, <, applespi->tp_dim_min_y);
> + UPDATE_DIMENSIONS(f->abs_y, >, applespi->tp_dim_max_y);
> +
> + #undef UPDATE_DIMENSIONS
> +}
> +static void
> +applespi_remap_fn_key(struct keyboard_protocol *keyboard_protocol)
> +{
> + unsigned char tmp;
What about
u8 bit = BIT(fnremap - 1);
> + if (!fnremap || fnremap > ARRAY_SIZE(applespi_controlcodes) ||
> + !applespi_controlcodes[fnremap - 1])
> + return;
> +
> + tmp = keyboard_protocol->fn_pressed;
> + keyboard_protocol->fn_pressed =
> + !!(keyboard_protocol->modifiers & BIT(fnremap - 1));
... & bit);
and so on?
> + if (tmp)
> + keyboard_protocol->modifiers |= BIT(fnremap - 1);
> + else
> + keyboard_protocol->modifiers &= ~BIT(fnremap - 1);
> +}
> +static void
> +applespi_handle_keyboard_event(struct applespi_data *applespi,
> + struct keyboard_protocol *keyboard_protocol)
> +{
> + int i, j;
> + unsigned int key;
> + bool still_pressed;
> + bool is_overflow;
Perhaps reversed xmas tree order?
> +
> + compiletime_assert(ARRAY_SIZE(applespi_controlcodes) ==
> + sizeof_field(struct keyboard_protocol, modifiers) * 8,
> + "applespi_controlcodes has wrong number of entries");
> +
> + /* check for rollover overflow, which is signalled by all keys == 1 */
> + is_overflow = true;
> +
> + for (i = 0; i < MAX_ROLLOVER; i++) {
> + if (keyboard_protocol->keys_pressed[i] != 1) {
> + is_overflow = false;
> + break;
> + }
> + }
> +
> + if (is_overflow)
> + return;
Isn't it simple
if (i == MAX_ROLLOVER)
w/o need of additional variable?
> + /* remap fn key if desired */
> + applespi_remap_fn_key(keyboard_protocol);
> +
> + /* check released keys */
> + for (i = 0; i < MAX_ROLLOVER; i++) {
> + still_pressed = false;
> + for (j = 0; j < MAX_ROLLOVER; j++) {
> + if (applespi->last_keys_pressed[i] ==
> + keyboard_protocol->keys_pressed[j]) {
> + still_pressed = true;
> + break;
> + }
> + }
> +
> + if (still_pressed)
> + continue;
Similar idea here.
> +
> + key = applespi_code_to_key(applespi->last_keys_pressed[i],
> + applespi->last_keys_fn_pressed[i]);
> + input_report_key(applespi->keyboard_input_dev, key, 0);
> + applespi->last_keys_fn_pressed[i] = 0;
> + }
> + /* check pressed keys */
> + for (i = 0; i < MAX_ROLLOVER; i++) {
> + if (keyboard_protocol->keys_pressed[i] <
> + ARRAY_SIZE(applespi_scancodes) &&
> + keyboard_protocol->keys_pressed[i] > 0) {
> + key = applespi_code_to_key(
> + keyboard_protocol->keys_pressed[i],
> + keyboard_protocol->fn_pressed);
> + input_report_key(applespi->keyboard_input_dev, key, 1);
> + applespi->last_keys_fn_pressed[i] =
> + keyboard_protocol->fn_pressed;
> + }
> + }
> +
> + /* check control keys */
> + for (i = 0; i < ARRAY_SIZE(applespi_controlcodes); i++) {
> + if (keyboard_protocol->modifiers & BIT(i))
> + input_report_key(applespi->keyboard_input_dev,
> + applespi_controlcodes[i], 1);
> + else
> + input_report_key(applespi->keyboard_input_dev,
> + applespi_controlcodes[i], 0);
> + }
> +
> + /* check function key */
> + if (keyboard_protocol->fn_pressed && !applespi->last_fn_pressed)
> + input_report_key(applespi->keyboard_input_dev, KEY_FN, 1);
> + else if (!keyboard_protocol->fn_pressed && applespi->last_fn_pressed)
> + input_report_key(applespi->keyboard_input_dev, KEY_FN, 0);
> + applespi->last_fn_pressed = keyboard_protocol->fn_pressed;
> +
> + /* done */
> + input_sync(applespi->keyboard_input_dev);
> + memcpy(&applespi->last_keys_pressed, keyboard_protocol->keys_pressed,
> + sizeof(applespi->last_keys_pressed));
> +}
> +static int
> +applespi_register_touchpad_device(struct applespi_data *applespi,
> + struct touchpad_info_protocol *rcvd_tp_info)
> +{
> + const struct applespi_tp_info *tp_info;
> + struct input_dev *touchpad_input_dev;
> + int sts;
> +
> + /* set up touchpad dimensions */
> + tp_info = applespi_find_touchpad_info(rcvd_tp_info->model_no);
> + if (!tp_info) {
> + dev_warn(&(applespi)->spi->dev,
I'm not sure what parens are helping with (here and everywhere with device parameter)?
> + "Unknown touchpad model %x - falling back to MB8 touchpad\n",
> + rcvd_tp_info->model_no);
> + tp_info = &applespi_tp_models[0].tp_info;
> + }
> + return 0;
> +}
> +static int applespi_probe(struct spi_device *spi)
> +{
> + struct applespi_data *applespi;
> + acpi_status acpi_sts;
> + int sts, i;
> + unsigned long long gpe, usb_status;
> +
> + /* check if the USB interface is present and enabled already */
> + acpi_sts = acpi_evaluate_integer(ACPI_HANDLE(&spi->dev), "UIST", NULL,
> + &usb_status);
... see below ...
> + if (ACPI_SUCCESS(acpi_sts) && usb_status) {
> + /* let the USB driver take over instead */
> + dev_info(&spi->dev, "USB interface already enabled\n");
> + return -ENODEV;
> + }
> +
> + /* allocate driver data */
> + applespi = devm_kzalloc(&spi->dev, sizeof(*applespi), GFP_KERNEL);
> + if (!applespi)
> + return -ENOMEM;
> +
> + applespi->spi = spi;
> + applespi->handle = ACPI_HANDLE(&spi->dev);
AFAICS this is local variable, why put it in the data structure?
And above you are not using this, btw.
> + } else {
> + struct dentry *ret;
> +
> + ret = debugfs_create_bool("enable_tp_dim", 0600,
> + applespi->debugfs_root,
> + &applespi->debug_tp_dim);
> + if (IS_ERR(ret))
> + dev_warn(&(applespi)->spi->dev,
> + "Error creating debugfs entry enable_tp_dim (%ld)\n",
> + PTR_ERR(ret));
Can ret be NULL?
dev_dbg() looks more appropriate.
> +
> + ret = debugfs_create_file("tp_dim", 0400,
> + applespi->debugfs_root, applespi,
> + &applespi_tp_dim_fops);
> + if (IS_ERR(ret))
> + dev_warn(&(applespi)->spi->dev,
> + "Error creating debugfs entry tp_dim (%ld)\n",
> + PTR_ERR(ret));
Ditto.
> + }
> +
> + return 0;
> +}
--
With Best Regards,
Andy Shevchenko
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