--- /dev/null
+/*
+ * dm355evm_keys.c - support buttons and IR remote on DM355 EVM board
+ *
+ * Copyright (c) 2008 by David Brownell
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/input/sparse-keymap.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+
+#include <linux/i2c/dm355evm_msp.h>
+#include <linux/module.h>
+
+
+/*
+ * The MSP430 firmware on the DM355 EVM monitors on-board pushbuttons
+ * and an IR receptor used for the remote control. When any key is
+ * pressed, or its autorepeat kicks in, an event is sent. This driver
+ * read those events from the small (32 event) queue and reports them.
+ *
+ * Note that physically there can only be one of these devices.
+ *
+ * This driver was tested with firmware revision A4.
+ */
+struct dm355evm_keys {
+ struct input_dev *input;
+ struct device *dev;
+ int irq;
+};
+
+/* These initial keycodes can be remapped */
+static const struct key_entry dm355evm_keys[] = {
+ /*
+ * Pushbuttons on the EVM board ... note that the labels for these
+ * are SW10/SW11/etc on the PC board. The left/right orientation
+ * comes only from the firmware's documentation, and presumes the
+ * power connector is immediately in front of you and the IR sensor
+ * is to the right. (That is, rotate the board counter-clockwise
+ * by 90 degrees from the SW10/etc and "DM355 EVM" labels.)
+ */
+ { KE_KEY, 0x00d8, { KEY_OK } }, /* SW12 */
+ { KE_KEY, 0x00b8, { KEY_UP } }, /* SW13 */
+ { KE_KEY, 0x00e8, { KEY_DOWN } }, /* SW11 */
+ { KE_KEY, 0x0078, { KEY_LEFT } }, /* SW14 */
+ { KE_KEY, 0x00f0, { KEY_RIGHT } }, /* SW10 */
+
+ /*
+ * IR buttons ... codes assigned to match the universal remote
+ * provided with the EVM (Philips PM4S) using DVD code 0020.
+ *
+ * These event codes match firmware documentation, but other
+ * remote controls could easily send more RC5-encoded events.
+ * The PM4S manual was used in several cases to help select
+ * a keycode reflecting the intended usage.
+ *
+ * RC5 codes are 14 bits, with two start bits (0x3 prefix)
+ * and a toggle bit (masked out below).
+ */
+ { KE_KEY, 0x300c, { KEY_POWER } }, /* NOTE: docs omit this */
+ { KE_KEY, 0x3000, { KEY_NUMERIC_0 } },
+ { KE_KEY, 0x3001, { KEY_NUMERIC_1 } },
+ { KE_KEY, 0x3002, { KEY_NUMERIC_2 } },
+ { KE_KEY, 0x3003, { KEY_NUMERIC_3 } },
+ { KE_KEY, 0x3004, { KEY_NUMERIC_4 } },
+ { KE_KEY, 0x3005, { KEY_NUMERIC_5 } },
+ { KE_KEY, 0x3006, { KEY_NUMERIC_6 } },
+ { KE_KEY, 0x3007, { KEY_NUMERIC_7 } },
+ { KE_KEY, 0x3008, { KEY_NUMERIC_8 } },
+ { KE_KEY, 0x3009, { KEY_NUMERIC_9 } },
+ { KE_KEY, 0x3022, { KEY_ENTER } },
+ { KE_KEY, 0x30ec, { KEY_MODE } }, /* "tv/vcr/..." */
+ { KE_KEY, 0x300f, { KEY_SELECT } }, /* "info" */
+ { KE_KEY, 0x3020, { KEY_CHANNELUP } }, /* "up" */
+ { KE_KEY, 0x302e, { KEY_MENU } }, /* "in/out" */
+ { KE_KEY, 0x3011, { KEY_VOLUMEDOWN } }, /* "left" */
+ { KE_KEY, 0x300d, { KEY_MUTE } }, /* "ok" */
+ { KE_KEY, 0x3010, { KEY_VOLUMEUP } }, /* "right" */
+ { KE_KEY, 0x301e, { KEY_SUBTITLE } }, /* "cc" */
+ { KE_KEY, 0x3021, { KEY_CHANNELDOWN } },/* "down" */
+ { KE_KEY, 0x3022, { KEY_PREVIOUS } },
+ { KE_KEY, 0x3026, { KEY_SLEEP } },
+ { KE_KEY, 0x3172, { KEY_REWIND } }, /* NOTE: docs wrongly say 0x30ca */
+ { KE_KEY, 0x3175, { KEY_PLAY } },
+ { KE_KEY, 0x3174, { KEY_FASTFORWARD } },
+ { KE_KEY, 0x3177, { KEY_RECORD } },
+ { KE_KEY, 0x3176, { KEY_STOP } },
+ { KE_KEY, 0x3169, { KEY_PAUSE } },
+};
+
+/*
+ * Because we communicate with the MSP430 using I2C, and all I2C calls
+ * in Linux sleep, we use a threaded IRQ handler. The IRQ itself is
+ * active low, but we go through the GPIO controller so we can trigger
+ * on falling edges and not worry about enabling/disabling the IRQ in
+ * the keypress handling path.
+ */
+static irqreturn_t dm355evm_keys_irq(int irq, void *_keys)
+{
+ static u16 last_event;
+ struct dm355evm_keys *keys = _keys;
+ const struct key_entry *ke;
+ unsigned int keycode;
+ int status;
+ u16 event;
+
+ /* For simplicity we ignore INPUT_COUNT and just read
+ * events until we get the "queue empty" indicator.
+ * Reading INPUT_LOW decrements the count.
+ */
+ for (;;) {
+ status = dm355evm_msp_read(DM355EVM_MSP_INPUT_HIGH);
+ if (status < 0) {
+ dev_dbg(keys->dev, "input high err %d\n",
+ status);
+ break;
+ }
+ event = status << 8;
+
+ status = dm355evm_msp_read(DM355EVM_MSP_INPUT_LOW);
+ if (status < 0) {
+ dev_dbg(keys->dev, "input low err %d\n",
+ status);
+ break;
+ }
+ event |= status;
+ if (event == 0xdead)
+ break;
+
+ /* Press and release a button: two events, same code.
+ * Press and hold (autorepeat), then release: N events
+ * (N > 2), same code. For RC5 buttons the toggle bits
+ * distinguish (for example) "1-autorepeat" from "1 1";
+ * but PCB buttons don't support that bit.
+ *
+ * So we must synthesize release events. We do that by
+ * mapping events to a press/release event pair; then
+ * to avoid adding extra events, skip the second event
+ * of each pair.
+ */
+ if (event == last_event) {
+ last_event = 0;
+ continue;
+ }
+ last_event = event;
+
+ /* ignore the RC5 toggle bit */
+ event &= ~0x0800;
+
+ /* find the key, or report it as unknown */
+ ke = sparse_keymap_entry_from_scancode(keys->input, event);
+ keycode = ke ? ke->keycode : KEY_UNKNOWN;
+ dev_dbg(keys->dev,
+ "input event 0x%04x--> keycode %d\n",
+ event, keycode);
+
+ /* report press + release */
+ input_report_key(keys->input, keycode, 1);
+ input_sync(keys->input);
+ input_report_key(keys->input, keycode, 0);
+ input_sync(keys->input);
+ }
+
+ return IRQ_HANDLED;
+}
+
+/*----------------------------------------------------------------------*/
+
+static int dm355evm_keys_probe(struct platform_device *pdev)
+{
+ struct dm355evm_keys *keys;
+ struct input_dev *input;
+ int status;
+
+ /* allocate instance struct and input dev */
+ keys = kzalloc(sizeof *keys, GFP_KERNEL);
+ input = input_allocate_device();
+ if (!keys || !input) {
+ status = -ENOMEM;
+ goto fail1;
+ }
+
+ keys->dev = &pdev->dev;
+ keys->input = input;
+
+ /* set up "threaded IRQ handler" */
+ status = platform_get_irq(pdev, 0);
+ if (status < 0)
+ goto fail1;
+ keys->irq = status;
+
+ input_set_drvdata(input, keys);
+
+ input->name = "DM355 EVM Controls";
+ input->phys = "dm355evm/input0";
+ input->dev.parent = &pdev->dev;
+
+ input->id.bustype = BUS_I2C;
+ input->id.product = 0x0355;
+ input->id.version = dm355evm_msp_read(DM355EVM_MSP_FIRMREV);
+
+ status = sparse_keymap_setup(input, dm355evm_keys, NULL);
+ if (status)
+ goto fail1;
+
+ /* REVISIT: flush the event queue? */
+
+ status = request_threaded_irq(keys->irq, NULL, dm355evm_keys_irq,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ dev_name(&pdev->dev), keys);
+ if (status < 0)
+ goto fail2;
+
+ /* register */
+ status = input_register_device(input);
+ if (status < 0)
+ goto fail3;
+
+ platform_set_drvdata(pdev, keys);
+
+ return 0;
+
+fail3:
+ free_irq(keys->irq, keys);
+fail2:
+ sparse_keymap_free(input);
+fail1:
+ input_free_device(input);
+ kfree(keys);
+ dev_err(&pdev->dev, "can't register, err %d\n", status);
+
+ return status;
+}
+
+static int dm355evm_keys_remove(struct platform_device *pdev)
+{
+ struct dm355evm_keys *keys = platform_get_drvdata(pdev);
+
+ free_irq(keys->irq, keys);
+ sparse_keymap_free(keys->input);
+ input_unregister_device(keys->input);
+ kfree(keys);
+
+ return 0;
+}
+
+/* REVISIT: add suspend/resume when DaVinci supports it. The IRQ should
+ * be able to wake up the system. When device_may_wakeup(&pdev->dev), call
+ * enable_irq_wake() on suspend, and disable_irq_wake() on resume.
+ */
+
+/*
+ * I2C is used to talk to the MSP430, but this platform device is
+ * exposed by an MFD driver that manages I2C communications.
+ */
+static struct platform_driver dm355evm_keys_driver = {
+ .probe = dm355evm_keys_probe,
+ .remove = dm355evm_keys_remove,
+ .driver = {
+ .name = "dm355evm_keys",
+ },
+};
+module_platform_driver(dm355evm_keys_driver);
+
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff