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Diffstat (limited to 'drivers/input/misc/sgi_btns.c')
-rw-r--r--drivers/input/misc/sgi_btns.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/input/misc/sgi_btns.c b/drivers/input/misc/sgi_btns.c
new file mode 100644
index 0000000000..0657d785b3
--- /dev/null
+++ b/drivers/input/misc/sgi_btns.c
@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * SGI Volume Button interface driver
+ *
+ * Copyright (C) 2008 Thomas Bogendoerfer <tsbogend@alpha.franken.de>
+ */
+#include <linux/input.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#ifdef CONFIG_SGI_IP22
+#include <asm/sgi/ioc.h>
+
+static inline u8 button_status(void)
+{
+ u8 status;
+
+ status = readb(&sgioc->panel) ^ 0xa0;
+ return ((status & 0x80) >> 6) | ((status & 0x20) >> 5);
+}
+#endif
+
+#ifdef CONFIG_SGI_IP32
+#include <asm/ip32/mace.h>
+
+static inline u8 button_status(void)
+{
+ u64 status;
+
+ status = readq(&mace->perif.audio.control);
+ writeq(status & ~(3U << 23), &mace->perif.audio.control);
+
+ return (status >> 23) & 3;
+}
+#endif
+
+#define BUTTONS_POLL_INTERVAL 30 /* msec */
+#define BUTTONS_COUNT_THRESHOLD 3
+
+static const unsigned short sgi_map[] = {
+ KEY_VOLUMEDOWN,
+ KEY_VOLUMEUP
+};
+
+struct buttons_dev {
+ unsigned short keymap[ARRAY_SIZE(sgi_map)];
+ int count[ARRAY_SIZE(sgi_map)];
+};
+
+static void handle_buttons(struct input_dev *input)
+{
+ struct buttons_dev *bdev = input_get_drvdata(input);
+ u8 status;
+ int i;
+
+ status = button_status();
+
+ for (i = 0; i < ARRAY_SIZE(bdev->keymap); i++) {
+ if (status & (1U << i)) {
+ if (++bdev->count[i] == BUTTONS_COUNT_THRESHOLD) {
+ input_event(input, EV_MSC, MSC_SCAN, i);
+ input_report_key(input, bdev->keymap[i], 1);
+ input_sync(input);
+ }
+ } else {
+ if (bdev->count[i] >= BUTTONS_COUNT_THRESHOLD) {
+ input_event(input, EV_MSC, MSC_SCAN, i);
+ input_report_key(input, bdev->keymap[i], 0);
+ input_sync(input);
+ }
+ bdev->count[i] = 0;
+ }
+ }
+}
+
+static int sgi_buttons_probe(struct platform_device *pdev)
+{
+ struct buttons_dev *bdev;
+ struct input_dev *input;
+ int error, i;
+
+ bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL);
+ if (!bdev)
+ return -ENOMEM;
+
+ input = devm_input_allocate_device(&pdev->dev);
+ if (!input)
+ return -ENOMEM;
+
+ memcpy(bdev->keymap, sgi_map, sizeof(bdev->keymap));
+
+ input_set_drvdata(input, bdev);
+
+ input->name = "SGI buttons";
+ input->phys = "sgi/input0";
+ input->id.bustype = BUS_HOST;
+
+ input->keycode = bdev->keymap;
+ input->keycodemax = ARRAY_SIZE(bdev->keymap);
+ input->keycodesize = sizeof(unsigned short);
+
+ input_set_capability(input, EV_MSC, MSC_SCAN);
+ __set_bit(EV_KEY, input->evbit);
+ for (i = 0; i < ARRAY_SIZE(sgi_map); i++)
+ __set_bit(bdev->keymap[i], input->keybit);
+ __clear_bit(KEY_RESERVED, input->keybit);
+
+ error = input_setup_polling(input, handle_buttons);
+ if (error)
+ return error;
+
+ input_set_poll_interval(input, BUTTONS_POLL_INTERVAL);
+
+ error = input_register_device(input);
+ if (error)
+ return error;
+
+ return 0;
+}
+
+static struct platform_driver sgi_buttons_driver = {
+ .probe = sgi_buttons_probe,
+ .driver = {
+ .name = "sgibtns",
+ },
+};
+module_platform_driver(sgi_buttons_driver);
+
+MODULE_LICENSE("GPL");